#!/usr/bin/python
# Copyright (c) 2018 Ansible Project
# GNU General Public License v3.0+ (see COPYING or https://www.gnu.org/licenses/gpl-3.0.txt)

from __future__ import absolute_import, division, print_function
__metaclass__ = type


DOCUMENTATION = r'''
---
module: rds_instance
version_added: 1.0.0
short_description: Manage RDS instances
description:
    - Create, modify, and delete RDS instances.
extends_documentation_fragment:
- amazon.aws.aws
- amazon.aws.ec2

author:
    - Sloane Hertel (@s-hertel)

options:
  # General module options
    state:
        description:
          - Whether the snapshot should exist or not. I(rebooted) is not idempotent and will leave the DB instance in a running state
            and start it prior to rebooting if it was stopped. I(present) will leave the DB instance in the current running/stopped state,
            (running if creating the DB instance).
          - I(state=running) and I(state=started) are synonyms, as are I(state=rebooted) and I(state=restarted). Note - rebooting the instance
            is not idempotent.
        choices: ['present', 'absent', 'terminated', 'running', 'started', 'stopped', 'rebooted', 'restarted']
        default: 'present'
        type: str
    creation_source:
        description: Which source to use if restoring from a template (an existing instance, S3 bucket, or snapshot).
        choices: ['snapshot', 's3', 'instance']
        type: str
    force_update_password:
        description:
          - Set to C(True) to update your instance password with I(master_user_password). Since comparing passwords to determine
            if it needs to be updated is not possible this is set to False by default to allow idempotence.
        type: bool
        default: False
    purge_cloudwatch_logs_exports:
        description: Set to False to retain any enabled cloudwatch logs that aren't specified in the task and are associated with the instance.
        type: bool
        default: True
    purge_tags:
        description: Set to False to retain any tags that aren't specified in task and are associated with the instance.
        type: bool
        default: True
    read_replica:
        description:
          - Set to C(False) to promote a read replica instance or true to create one. When creating a read replica C(creation_source) should
            be set to 'instance' or not provided. C(source_db_instance_identifier) must be provided with this option.
        type: bool
    wait:
        description:
          - Whether to wait for the instance to be available, stopped, or deleted. At a later time a I(wait_timeout) option may be added.
            Following each API call to create/modify/delete the instance a waiter is used with a 60 second delay 30 times until the instance reaches
            the expected state (available/stopped/deleted). The total task time may also be influenced by AWSRetry which helps stabilize if the
            instance is in an invalid state to operate on to begin with (such as if you try to stop it when it is in the process of rebooting).
            If setting this to False task retries and delays may make your playbook execution better handle timeouts for major modifications.
        type: bool
        default: True

    # Options that have a corresponding boto3 parameter
    allocated_storage:
        description:
          - The amount of storage (in gibibytes) to allocate for the DB instance.
        type: int
    allow_major_version_upgrade:
        description:
          - Whether to allow major version upgrades.
        type: bool
    apply_immediately:
        description:
          - A value that specifies whether modifying an instance with I(new_db_instance_identifier) and I(master_user_password)
            should be applied as soon as possible, regardless of the I(preferred_maintenance_window) setting. If false, changes
            are applied during the next maintenance window.
        type: bool
        default: False
    auto_minor_version_upgrade:
        description:
          - Whether minor version upgrades are applied automatically to the DB instance during the maintenance window.
        type: bool
    availability_zone:
        description:
          - A list of EC2 Availability Zones that the DB instance can be created in.
            May be used when creating an instance or when restoring from S3 or a snapshot. Mutually exclusive with I(multi_az).
        aliases:
          - az
          - zone
        type: str
    backup_retention_period:
        description:
          - The number of days for which automated backups are retained.
          - When set to C(0), automated backups will be disabled. (Not applicable if the DB instance is a source to read replicas)
          - May be used when creating a new instance, when restoring from S3, or when modifying an instance.
        type: int
    ca_certificate_identifier:
        description:
          - The identifier of the CA certificate for the DB instance.
        type: str
    character_set_name:
        description:
          - The character set to associate with the DB instance.
        type: str
    copy_tags_to_snapshot:
        description:
          - Whether or not to copy all tags from the DB instance to snapshots of the instance. When initially creating
            a DB instance the RDS API defaults this to false if unspecified.
        type: bool
    db_cluster_identifier:
        description:
          - The DB cluster (lowercase) identifier to add the aurora DB instance to. The identifier must contain from 1 to
            63 letters, numbers, or hyphens and the first character must be a letter and may not end in a hyphen or
            contain consecutive hyphens.
        aliases:
          - cluster_id
        type: str
    db_instance_class:
        description:
          - The compute and memory capacity of the DB instance, for example db.t2.micro.
        aliases:
          - class
          - instance_type
        type: str
    db_instance_identifier:
        description:
          - The DB instance (lowercase) identifier. The identifier must contain from 1 to 63 letters, numbers, or
            hyphens and the first character must be a letter and may not end in a hyphen or contain consecutive hyphens.
        aliases:
          - instance_id
          - id
        required: True
        type: str
    db_name:
        description:
          - The name for your database. If a name is not provided Amazon RDS will not create a database.
        type: str
    db_parameter_group_name:
        description:
          - The name of the DB parameter group to associate with this DB instance. When creating the DB instance if this
            argument is omitted the default DBParameterGroup for the specified engine is used.
        type: str
    db_security_groups:
        description:
          - (EC2-Classic platform) A list of DB security groups to associate with this DB instance.
        type: list
        elements: str
    db_snapshot_identifier:
        description:
          - The identifier or ARN of the DB snapshot to restore from when using I(creation_source=snapshot).
        type: str
        aliases:
          - snapshot_identifier
          - snapshot_id
    db_subnet_group_name:
        description:
          - The DB subnet group name to use for the DB instance.
        aliases:
          - subnet_group
        type: str
    deletion_protection:
        description:
          -  A value that indicates whether the DB instance has deletion protection enabled.
             The database can't be deleted when deletion protection is enabled.
             By default, deletion protection is disabled.
        type: bool
        version_added: 3.3.0
    domain:
        description:
          - The Active Directory Domain to restore the instance in.
        type: str
    domain_iam_role_name:
        description:
          - The name of the IAM role to be used when making API calls to the Directory Service.
        type: str
    enable_cloudwatch_logs_exports:
        description:
          - A list of log types that need to be enabled for exporting to CloudWatch Logs.
        aliases:
          - cloudwatch_log_exports
        type: list
        elements: str
    enable_iam_database_authentication:
        description:
          - Enable mapping of AWS Identity and Access Management (IAM) accounts to database accounts.
            If this option is omitted when creating the instance, Amazon RDS sets this to False.
        type: bool
    enable_performance_insights:
        description:
          - Whether to enable Performance Insights for the DB instance.
        type: bool
    engine:
        description:
          - The name of the database engine to be used for this DB instance. This is required to create an instance.
        choices: ['aurora', 'aurora-mysql', 'aurora-postgresql', 'mariadb', 'mysql', 'oracle-ee', 'oracle-ee-cdb',
                  'oracle-se2', 'oracle-se2-cdb', 'postgres', 'sqlserver-ee', 'sqlserver-se', 'sqlserver-ex', 'sqlserver-web']
        type: str
    engine_version:
        description:
          - The version number of the database engine to use. For Aurora MySQL that could be 5.6.10a , 5.7.12.
            Aurora PostgreSQL example, 9.6.3
        type: str
    final_db_snapshot_identifier:
        description:
          - The DB instance snapshot identifier of the new DB instance snapshot created when I(skip_final_snapshot) is false.
        aliases:
          - final_snapshot_identifier
        type: str
    force_failover:
        description:
          - Set to true to conduct the reboot through a MultiAZ failover.
        type: bool
    iam_roles:
        description:
          - List of Amazon Web Services Identity and Access Management (IAM) roles to associate with DB instance.
        type: list
        elements: dict
        suboptions:
          feature_name:
            description:
              - The name of the feature associated with the IAM role.
            type: str
            required: yes
          role_arn:
            description:
              - The ARN of the IAM role to associate with the DB instance.
            type: str
            required: yes
        version_added: 3.3.0
    iops:
        description:
          - The Provisioned IOPS (I/O operations per second) value. Is only set when using I(storage_type) is set to io1.
        type: int
    kms_key_id:
        description:
          - The ARN of the AWS KMS key identifier for an encrypted DB instance. If you are creating a DB instance with the
            same AWS account that owns the KMS encryption key used to encrypt the new DB instance, then you can use the KMS key
            alias instead of the ARN for the KM encryption key.
          - If I(storage_encrypted) is true and and this option is not provided, the default encryption key is used.
        type: str
    license_model:
        description:
          - The license model for the DB instance.
          - Several options are license-included, bring-your-own-license, and general-public-license.
          - This option can also be omitted to default to an accepted value.
        type: str
    master_user_password:
        description:
          - An 8-41 character password for the master database user. The password can contain any printable ASCII character
            except "/", """, or "@". To modify the password use I(force_update_password). Use I(apply immediately) to change
            the password immediately, otherwise it is updated during the next maintenance window.
        aliases:
          - password
        type: str
    master_username:
        description:
          - The name of the master user for the DB instance. Must be 1-16 letters or numbers and begin with a letter.
        aliases:
          - username
        type: str
    max_allocated_storage:
        description:
          - The upper limit to which Amazon RDS can automatically scale the storage of the DB instance.
        type: int
    monitoring_interval:
        description:
          - The interval, in seconds, when Enhanced Monitoring metrics are collected for the DB instance. To disable collecting
            metrics, specify 0. Amazon RDS defaults this to 0 if omitted when initially creating a DB instance.
        type: int
    monitoring_role_arn:
        description:
          - The ARN for the IAM role that permits RDS to send enhanced monitoring metrics to Amazon CloudWatch Logs.
        type: str
    multi_az:
        description:
          - Specifies if the DB instance is a Multi-AZ deployment. Mutually exclusive with I(availability_zone).
        type: bool
    new_db_instance_identifier:
        description:
          - The new DB instance (lowercase) identifier for the DB instance when renaming a DB instance. The identifier must contain
            from 1 to 63 letters, numbers, or hyphens and the first character must be a letter and may not end in a hyphen or
            contain consecutive hyphens. Use I(apply_immediately) to rename immediately, otherwise it is updated during the
            next maintenance window.
        aliases:
          - new_instance_id
          - new_id
        type: str
    option_group_name:
        description:
          - The option group to associate with the DB instance.
        type: str
    performance_insights_kms_key_id:
        description:
          - The AWS KMS key identifier (ARN, name, or alias) for encryption of Performance Insights data.
        type: str
    performance_insights_retention_period:
        description:
          - The amount of time, in days, to retain Performance Insights data. Valid values are 7 or 731.
        type: int
    port:
        description:
          - The port number on which the instances accept connections.
        type: int
    preferred_backup_window:
        description:
          - The daily time range (in UTC) of at least 30 minutes, during which automated backups are created if automated backups are
            enabled using I(backup_retention_period). The option must be in the format of "hh24:mi-hh24:mi" and not conflict with
            I(preferred_maintenance_window).
        aliases:
          - backup_window
        type: str
    preferred_maintenance_window:
        description:
          - The weekly time range (in UTC) of at least 30 minutes, during which system maintenance can occur. The option must
            be in the format "ddd:hh24:mi-ddd:hh24:mi" where ddd is one of Mon, Tue, Wed, Thu, Fri, Sat, Sun.
        aliases:
          - maintenance_window
        type: str
    processor_features:
        description:
          - A dictionary of Name, Value pairs to indicate the number of CPU cores and the number of threads per core for the
            DB instance class of the DB instance. Names are threadsPerCore and coreCount.
            Set this option to an empty dictionary to use the default processor features.
        suboptions:
          threadsPerCore:
            description: The number of threads per core
          coreCount:
            description: The number of CPU cores
        type: dict
    promotion_tier:
        description:
          - An integer that specifies the order in which an Aurora Replica is promoted to the primary instance after a failure of
            the existing primary instance.
        type: str
    publicly_accessible:
        description:
          - Specifies the accessibility options for the DB instance. A value of true specifies an Internet-facing instance with
            a publicly resolvable DNS name, which resolves to a public IP address. A value of false specifies an internal
            instance with a DNS name that resolves to a private IP address.
        type: bool
    purge_iam_roles:
        description:
          - Set to C(True) to remove any IAM roles that aren't specified in the task and are associated with the instance.
        type: bool
        default: False
        version_added: 3.3.0
    restore_time:
        description:
          - If using I(creation_source=instance) this indicates the UTC date and time to restore from the source instance.
            For example, "2009-09-07T23:45:00Z".
          - May alternatively set I(use_latest_restore_time=True).
          - Only one of I(use_latest_restorable_time) and I(restore_time) may be provided.
        type: str
    s3_bucket_name:
        description:
          - The name of the Amazon S3 bucket that contains the data used to create the Amazon DB instance.
        type: str
    s3_ingestion_role_arn:
        description:
          - The Amazon Resource Name (ARN) of the AWS Identity and Access Management (IAM) role that authorizes Amazon RDS to access
            the Amazon S3 bucket on your behalf.
        type: str
    s3_prefix:
        description:
          - The prefix for all of the file names that contain the data used to create the Amazon DB instance. If you do not
            specify a SourceS3Prefix value, then the Amazon DB instance is created by using all of the files in the Amazon S3 bucket.
        type: str
    skip_final_snapshot:
        description:
          - Whether a final DB instance snapshot is created before the DB instance is deleted. If this is false I(final_db_snapshot_identifier)
            must be provided.
        type: bool
        default: false
    source_db_instance_identifier:
        description:
          - The identifier or ARN of the source DB instance from which to restore when creating a read replica or spinning up a point-in-time
            DB instance using I(creation_source=instance). If the source DB is not in the same region this should be an ARN.
        type: str
    source_engine:
        description:
          - The identifier for the database engine that was backed up to create the files stored in the Amazon S3 bucket.
        choices:
          - mysql
        type: str
    source_engine_version:
        description:
          - The version of the database that the backup files were created from.
        type: str
    source_region:
        description:
          - The region of the DB instance from which the replica is created.
        type: str
    storage_encrypted:
        description:
          - Whether the DB instance is encrypted.
        type: bool
    storage_type:
        description:
          - The storage type to be associated with the DB instance. I(storage_type) does not apply to Aurora DB instances.
        choices:
          - standard
          - gp2
          - io1
        type: str
    tags:
        description:
          - A dictionary of key value pairs to assign the DB instance.
        type: dict
    tde_credential_arn:
        description:
          - The ARN from the key store with which to associate the instance for Transparent Data Encryption. This is
            supported by Oracle or SQL Server DB instances and may be used in conjunction with C(storage_encrypted)
            though it might slightly affect the performance of your database.
        aliases:
          - transparent_data_encryption_arn
        type: str
    tde_credential_password:
        description:
          - The password for the given ARN from the key store in order to access the device.
        aliases:
          - transparent_data_encryption_password
        type: str
    timezone:
        description:
          - The time zone of the DB instance.
        type: str
    use_latest_restorable_time:
        description:
          - Whether to restore the DB instance to the latest restorable backup time.
          - Only one of I(use_latest_restorable_time) and I(restore_time) may be provided.
        type: bool
        aliases:
          - restore_from_latest
    vpc_security_group_ids:
        description:
          - A list of EC2 VPC security groups to associate with the DB instance.
        type: list
        elements: str
    purge_security_groups:
        description:
          - Set to False to retain any enabled security groups that aren't specified in the task and are associated with the instance.
          - Can be applied to I(vpc_security_group_ids) and I(db_security_groups)
        type: bool
        default: True
        version_added: 1.5.0
'''

EXAMPLES = r'''
# Note: These examples do not set authentication details, see the AWS Guide for details.
- name: create minimal aurora instance in default VPC and default subnet group
  community.aws.rds_instance:
    engine: aurora
    db_instance_identifier: ansible-test-aurora-db-instance
    instance_type: db.t2.small
    password: "{{ password }}"
    username: "{{ username }}"
    cluster_id: ansible-test-cluster  # This cluster must exist - see rds_cluster to manage it

- name: Create a DB instance using the default AWS KMS encryption key
  community.aws.rds_instance:
    id: test-encrypted-db
    state: present
    engine: mariadb
    storage_encrypted: True
    db_instance_class: db.t2.medium
    username: "{{ username }}"
    password: "{{ password }}"
    allocated_storage: "{{ allocated_storage }}"

- name: remove the DB instance without a final snapshot
  community.aws.rds_instance:
    id: "{{ instance_id }}"
    state: absent
    skip_final_snapshot: True

- name: remove the DB instance with a final snapshot
  community.aws.rds_instance:
    id: "{{ instance_id }}"
    state: absent
    final_snapshot_identifier: "{{ snapshot_id }}"

- name: Add a new security group without purge
  community.aws.rds_instance:
    id: "{{ instance_id }}"
    state: present
    vpc_security_group_ids:
      - sg-0be17ba10c9286b0b
    purge_security_groups: false
  register: result

# Add IAM role to db instance
- name: Create IAM policy
  community.aws.iam_managed_policy:
    policy_name: "my-policy"
    policy: "{{ lookup('file','files/policy.json') }}"
    state: present
  register: iam_policy

- name: Create IAM role
  community.aws.iam_role:
    assume_role_policy_document: "{{ lookup('file','files/assume_policy.json') }}"
    name: "my-role"
    state: present
    managed_policy: "{{ iam_policy.policy.arn }}"
  register: iam_role

- name: Create DB instance with added IAM role
  community.aws.rds_instance:
    id: "my-instance-id"
    state: present
    engine: postgres
    engine_version: 14.2
    username: "{{ username }}"
    password: "{{ password }}"
    db_instance_class: db.m6g.large
    allocated_storage: "{{ allocated_storage }}"
    iam_roles:
      - role_arn: "{{ iam_role.arn }}"
        feature_name: 's3Export'

- name: Remove IAM role from DB instance
  community.aws.rds_instance:
    id: "my-instance-id"
    state: present
    purge_iam_roles: yes

# Restore DB instance from snapshot
- name: Create a snapshot and wait until completion
  community.aws.rds_instance_snapshot:
    instance_id: 'my-instance-id'
    snapshot_id: 'my-new-snapshot'
    state: present
    wait: yes
  register: snapshot

- name: Restore DB from snapshot
  community.aws.rds_instance:
    id: 'my-restored-db'
    creation_source: snapshot
    snapshot_identifier: 'my-new-snapshot'
    engine: mariadb
    state: present
  register: restored_db
'''

RETURN = r'''
allocated_storage:
  description: The allocated storage size in gigabytes. This is always 1 for aurora database engines.
  returned: always
  type: int
  sample: 20
associated_roles:
  description: The list of currently associated roles.
  returned: always
  type: list
  sample: []
auto_minor_version_upgrade:
  description: Whether minor engine upgrades are applied automatically to the DB instance during the maintenance window.
  returned: always
  type: bool
  sample: true
availability_zone:
  description: The availability zone for the DB instance.
  returned: always
  type: str
  sample: us-east-1f
backup_retention_period:
  description: The number of days for which automated backups are retained.
  returned: always
  type: int
  sample: 1
ca_certificate_identifier:
  description: The identifier of the CA certificate for the DB instance.
  returned: always
  type: str
  sample: rds-ca-2015
copy_tags_to_snapshot:
  description: Whether tags are copied from the DB instance to snapshots of the DB instance.
  returned: always
  type: bool
  sample: false
db_instance_arn:
  description: The Amazon Resource Name (ARN) for the DB instance.
  returned: always
  type: str
  sample: arn:aws:rds:us-east-1:123456789012:db:ansible-test
db_instance_class:
  description: The name of the compute and memory capacity class of the DB instance.
  returned: always
  type: str
  sample: db.m4.large
db_instance_identifier:
  description: The identifier of the DB instance
  returned: always
  type: str
  sample: ansible-test
db_instance_port:
  description: The port that the DB instance listens on.
  returned: always
  type: int
  sample: 0
db_instance_status:
  description: The current state of this database.
  returned: always
  type: str
  sample: stopped
db_parameter_groups:
  description: The list of DB parameter groups applied to this DB instance.
  returned: always
  type: complex
  contains:
    db_parameter_group_name:
      description: The name of the DP parameter group.
      returned: always
      type: str
      sample: default.mariadb10.0
    parameter_apply_status:
      description: The status of parameter updates.
      returned: always
      type: str
      sample: in-sync
db_security_groups:
  description: A list of DB security groups associated with this DB instance.
  returned: always
  type: list
  sample: []
db_subnet_group:
  description: The subnet group associated with the DB instance.
  returned: always
  type: complex
  contains:
    db_subnet_group_description:
      description: The description of the DB subnet group.
      returned: always
      type: str
      sample: default
    db_subnet_group_name:
      description: The name of the DB subnet group.
      returned: always
      type: str
      sample: default
    subnet_group_status:
      description: The status of the DB subnet group.
      returned: always
      type: str
      sample: Complete
    subnets:
      description: A list of Subnet elements.
      returned: always
      type: complex
      contains:
        subnet_availability_zone:
          description: The availability zone of the subnet.
          returned: always
          type: complex
          contains:
            name:
              description: The name of the Availability Zone.
              returned: always
              type: str
              sample: us-east-1c
        subnet_identifier:
          description: The ID of the subnet.
          returned: always
          type: str
          sample: subnet-12345678
        subnet_status:
          description: The status of the subnet.
          returned: always
          type: str
          sample: Active
    vpc_id:
      description: The VpcId of the DB subnet group.
      returned: always
      type: str
      sample: vpc-12345678
dbi_resource_id:
  description: The AWS Region-unique, immutable identifier for the DB instance.
  returned: always
  type: str
  sample: db-UHV3QRNWX4KB6GALCIGRML6QFA
deletion_protection:
  description: C(True) if the DB instance has deletion protection enabled, C(False) if not.
  returned: always
  type: bool
  sample: False
  version_added: 3.3.0
domain_memberships:
  description: The Active Directory Domain membership records associated with the DB instance.
  returned: always
  type: list
  sample: []
endpoint:
  description: The connection endpoint.
  returned: always
  type: complex
  contains:
    address:
      description: The DNS address of the DB instance.
      returned: always
      type: str
      sample: ansible-test.cvlrtwiennww.us-east-1.rds.amazonaws.com
    hosted_zone_id:
      description: The ID that Amazon Route 53 assigns when you create a hosted zone.
      returned: always
      type: str
      sample: ZTR2ITUGPA61AM
    port:
      description: The port that the database engine is listening on.
      returned: always
      type: int
      sample: 3306
engine:
  description: The database engine version.
  returned: always
  type: str
  sample: mariadb
engine_version:
  description: The database engine version.
  returned: always
  type: str
  sample: 10.0.35
iam_database_authentication_enabled:
  description: Whether mapping of AWS Identity and Access Management (IAM) accounts to database accounts is enabled.
  returned: always
  type: bool
  sample: false
instance_create_time:
  description: The date and time the DB instance was created.
  returned: always
  type: str
  sample: '2018-07-04T16:48:35.332000+00:00'
kms_key_id:
  description: The AWS KMS key identifier for the encrypted DB instance when storage_encrypted is true.
  returned: When storage_encrypted is true
  type: str
  sample: arn:aws:kms:us-east-1:123456789012:key/70c45553-ad2e-4a85-9f14-cfeb47555c33
latest_restorable_time:
  description: The latest time to which a database can be restored with point-in-time restore.
  returned: always
  type: str
  sample: '2018-07-04T16:50:50.642000+00:00'
license_model:
  description: The License model information for this DB instance.
  returned: always
  type: str
  sample: general-public-license
master_username:
  description: The master username for the DB instance.
  returned: always
  type: str
  sample: test
max_allocated_storage:
  description: The upper limit to which Amazon RDS can automatically scale the storage of the DB instance.
  returned: When max allocated storage is present.
  type: int
  sample: 100
monitoring_interval:
  description:
    - The interval, in seconds, between points when Enhanced Monitoring metrics are collected for the DB instance.
      0 means collecting Enhanced Monitoring metrics is disabled.
  returned: always
  type: int
  sample: 0
multi_az:
  description: Whether the DB instance is a Multi-AZ deployment.
  returned: always
  type: bool
  sample: false
option_group_memberships:
  description: The list of option group memberships for this DB instance.
  returned: always
  type: complex
  contains:
    option_group_name:
      description: The name of the option group that the instance belongs to.
      returned: always
      type: str
      sample: default:mariadb-10-0
    status:
      description: The status of the DB instance's option group membership.
      returned: always
      type: str
      sample: in-sync
pending_modified_values:
  description: The changes to the DB instance that are pending.
  returned: always
  type: complex
  contains: {}
performance_insights_enabled:
  description: True if Performance Insights is enabled for the DB instance, and otherwise false.
  returned: always
  type: bool
  sample: false
preferred_backup_window:
  description: The daily time range during which automated backups are created if automated backups are enabled.
  returned: always
  type: str
  sample: 07:01-07:31
preferred_maintenance_window:
  description: The weekly time range (in UTC) during which system maintenance can occur.
  returned: always
  type: str
  sample: sun:09:31-sun:10:01
publicly_accessible:
  description:
    - True for an Internet-facing instance with a publicly resolvable DNS name, False to indicate an
      internal instance with a DNS name that resolves to a private IP address.
  returned: always
  type: bool
  sample: true
read_replica_db_instance_identifiers:
  description: Identifiers of the Read Replicas associated with this DB instance.
  returned: always
  type: list
  sample: []
storage_encrypted:
  description: Whether the DB instance is encrypted.
  returned: always
  type: bool
  sample: false
storage_type:
  description: The storage type to be associated with the DB instance.
  returned: always
  type: str
  sample: standard
tags:
  description: A dictionary of tags associated with the DB instance.
  returned: always
  type: complex
  contains: {}
vpc_security_groups:
  description: A list of VPC security group elements that the DB instance belongs to.
  returned: always
  type: complex
  contains:
    status:
      description: The status of the VPC security group.
      returned: always
      type: str
      sample: active
    vpc_security_group_id:
      description: The name of the VPC security group.
      returned: always
      type: str
      sample: sg-12345678
'''

from time import sleep

try:
    import botocore
except ImportError:
    pass  # caught by AnsibleAWSModule


from ansible.module_utils._text import to_text
from ansible.module_utils.common.dict_transformations import camel_dict_to_snake_dict
from ansible.module_utils.six import string_types

from ansible_collections.amazon.aws.plugins.module_utils.core import AnsibleAWSModule
from ansible_collections.amazon.aws.plugins.module_utils.core import is_boto3_error_code
from ansible_collections.amazon.aws.plugins.module_utils.core import is_boto3_error_message
from ansible_collections.amazon.aws.plugins.module_utils.core import get_boto3_client_method_parameters
from ansible_collections.amazon.aws.plugins.module_utils.ec2 import ansible_dict_to_boto3_tag_list
from ansible_collections.amazon.aws.plugins.module_utils.ec2 import AWSRetry
from ansible_collections.amazon.aws.plugins.module_utils.ec2 import boto3_tag_list_to_ansible_dict
from ansible_collections.amazon.aws.plugins.module_utils.rds import arg_spec_to_rds_params
from ansible_collections.amazon.aws.plugins.module_utils.rds import call_method
from ansible_collections.amazon.aws.plugins.module_utils.rds import compare_iam_roles
from ansible_collections.amazon.aws.plugins.module_utils.rds import ensure_tags
from ansible_collections.amazon.aws.plugins.module_utils.rds import get_final_identifier
from ansible_collections.amazon.aws.plugins.module_utils.rds import get_rds_method_attribute
from ansible_collections.amazon.aws.plugins.module_utils.rds import get_tags
from ansible_collections.amazon.aws.plugins.module_utils.rds import update_iam_roles


valid_engines = ['aurora', 'aurora-mysql', 'aurora-postgresql', 'mariadb', 'mysql', 'oracle-ee', 'oracle-ee-cdb',
                 'oracle-se2', 'oracle-se2-cdb', 'postgres', 'sqlserver-ee', 'sqlserver-se', 'sqlserver-ex', 'sqlserver-web']

valid_engines_iam_roles = ['aurora-postgresql', 'oracle-ee', 'oracle-ee-cdb', 'oracle-se2', 'oracle-se2-cdb',
                           'postgres', 'sqlserver-ee', 'sqlserver-se', 'sqlserver-ex', 'sqlserver-web']


def get_rds_method_attribute_name(instance, state, creation_source, read_replica):
    method_name = None
    if state == 'absent' or state == 'terminated':
        if instance and instance['DBInstanceStatus'] not in ['deleting', 'deleted']:
            method_name = 'delete_db_instance'
    else:
        if instance:
            method_name = 'modify_db_instance'
        elif read_replica is True:
            method_name = 'create_db_instance_read_replica'
        elif creation_source == 'snapshot':
            method_name = 'restore_db_instance_from_db_snapshot'
        elif creation_source == 's3':
            method_name = 'restore_db_instance_from_s3'
        elif creation_source == 'instance':
            method_name = 'restore_db_instance_to_point_in_time'
        else:
            method_name = 'create_db_instance'
    return method_name


def get_instance(client, module, db_instance_id):
    try:
        for i in range(3):
            try:
                instance = client.describe_db_instances(DBInstanceIdentifier=db_instance_id)['DBInstances'][0]
                instance['Tags'] = get_tags(client, module, instance['DBInstanceArn'])
                if instance.get('ProcessorFeatures'):
                    instance['ProcessorFeatures'] = dict((feature['Name'], feature['Value']) for feature in instance['ProcessorFeatures'])
                if instance.get('PendingModifiedValues', {}).get('ProcessorFeatures'):
                    instance['PendingModifiedValues']['ProcessorFeatures'] = dict(
                        (feature['Name'], feature['Value'])
                        for feature in instance['PendingModifiedValues']['ProcessorFeatures']
                    )
                break
            except is_boto3_error_code('DBInstanceNotFound'):
                sleep(3)
        else:
            instance = {}
    except (botocore.exceptions.ClientError, botocore.exceptions.BotoCoreError) as e:  # pylint: disable=duplicate-except
        module.fail_json_aws(e, msg='Failed to describe DB instances')
    return instance


def get_final_snapshot(client, module, snapshot_identifier):
    try:
        snapshots = AWSRetry.jittered_backoff()(client.describe_db_snapshots)(DBSnapshotIdentifier=snapshot_identifier)
        if len(snapshots.get('DBSnapshots', [])) == 1:
            return snapshots['DBSnapshots'][0]
        return {}
    except is_boto3_error_code('DBSnapshotNotFound') as e:  # May not be using wait: True
        return {}
    except (botocore.exceptions.ClientError, botocore.exceptions.BotoCoreError) as e:  # pylint: disable=duplicate-except
        module.fail_json_aws(e, msg='Failed to retrieve information about the final snapshot')


def get_parameters(client, module, parameters, method_name):
    if method_name == 'restore_db_instance_to_point_in_time':
        parameters['TargetDBInstanceIdentifier'] = module.params['db_instance_identifier']

    required_options = get_boto3_client_method_parameters(client, method_name, required=True)
    if any(parameters.get(k) is None for k in required_options):
        module.fail_json(msg='To {0} requires the parameters: {1}'.format(
            get_rds_method_attribute(method_name, module).operation_description, required_options))
    options = get_boto3_client_method_parameters(client, method_name)
    parameters = dict((k, v) for k, v in parameters.items() if k in options and v is not None)

    if parameters.get('ProcessorFeatures') is not None:
        parameters['ProcessorFeatures'] = [{'Name': k, 'Value': to_text(v)} for k, v in parameters['ProcessorFeatures'].items()]

    # If this parameter is an empty list it can only be used with modify_db_instance (as the parameter UseDefaultProcessorFeatures)
    if parameters.get('ProcessorFeatures') == [] and not method_name == 'modify_db_instance':
        parameters.pop('ProcessorFeatures')

    if method_name in ['create_db_instance', 'create_db_instance_read_replica', 'restore_db_instance_from_db_snapshot']:
        if parameters.get('Tags'):
            parameters['Tags'] = ansible_dict_to_boto3_tag_list(parameters['Tags'])

    if method_name == 'modify_db_instance':
        parameters = get_options_with_changing_values(client, module, parameters)

    return parameters


def get_options_with_changing_values(client, module, parameters):
    instance_id = module.params['db_instance_identifier']
    purge_cloudwatch_logs = module.params['purge_cloudwatch_logs_exports']
    force_update_password = module.params['force_update_password']
    port = module.params['port']
    apply_immediately = parameters.pop('ApplyImmediately', None)
    cloudwatch_logs_enabled = module.params['enable_cloudwatch_logs_exports']
    purge_security_groups = module.params['purge_security_groups']

    if port:
        parameters['DBPortNumber'] = port
    if not force_update_password:
        parameters.pop('MasterUserPassword', None)
    if cloudwatch_logs_enabled:
        parameters['CloudwatchLogsExportConfiguration'] = cloudwatch_logs_enabled
    if not module.params['storage_type']:
        parameters.pop('Iops', None)

    instance = get_instance(client, module, instance_id)
    updated_parameters = get_changing_options_with_inconsistent_keys(parameters, instance, purge_cloudwatch_logs, purge_security_groups)
    updated_parameters.update(get_changing_options_with_consistent_keys(parameters, instance))
    parameters = updated_parameters

    if instance.get('StorageType') == 'io1':
        # Bundle Iops and AllocatedStorage while updating io1 RDS Instance
        current_iops = instance.get('PendingModifiedValues', {}).get('Iops', instance['Iops'])
        current_allocated_storage = instance.get('PendingModifiedValues', {}).get('AllocatedStorage', instance['AllocatedStorage'])
        new_iops = module.params.get('iops')
        new_allocated_storage = module.params.get('allocated_storage')

        if current_iops != new_iops or current_allocated_storage != new_allocated_storage:
            parameters['AllocatedStorage'] = new_allocated_storage
            parameters['Iops'] = new_iops

    if parameters.get('NewDBInstanceIdentifier') and instance.get('PendingModifiedValues', {}).get('DBInstanceIdentifier'):
        if parameters['NewDBInstanceIdentifier'] == instance['PendingModifiedValues']['DBInstanceIdentifier'] and not apply_immediately:
            parameters.pop('NewDBInstanceIdentifier')

    if parameters:
        parameters['DBInstanceIdentifier'] = instance_id
        if apply_immediately is not None:
            parameters['ApplyImmediately'] = apply_immediately

    return parameters


def get_current_attributes_with_inconsistent_keys(instance):
    options = {}
    if instance.get('PendingModifiedValues', {}).get('PendingCloudwatchLogsExports', {}).get('LogTypesToEnable', []):
        current_enabled = instance['PendingModifiedValues']['PendingCloudwatchLogsExports']['LogTypesToEnable']
        current_disabled = instance['PendingModifiedValues']['PendingCloudwatchLogsExports']['LogTypesToDisable']
        options['CloudwatchLogsExportConfiguration'] = {'LogTypesToEnable': current_enabled, 'LogTypesToDisable': current_disabled}
    else:
        options['CloudwatchLogsExportConfiguration'] = {'LogTypesToEnable': instance.get('EnabledCloudwatchLogsExports', []), 'LogTypesToDisable': []}
    if instance.get('PendingModifiedValues', {}).get('Port'):
        options['DBPortNumber'] = instance['PendingModifiedValues']['Port']
    else:
        options['DBPortNumber'] = instance['Endpoint']['Port']
    if instance.get('PendingModifiedValues', {}).get('DBSubnetGroupName'):
        options['DBSubnetGroupName'] = instance['PendingModifiedValues']['DBSubnetGroupName']
    else:
        options['DBSubnetGroupName'] = instance['DBSubnetGroup']['DBSubnetGroupName']
    if instance.get('PendingModifiedValues', {}).get('ProcessorFeatures'):
        options['ProcessorFeatures'] = instance['PendingModifiedValues']['ProcessorFeatures']
    else:
        options['ProcessorFeatures'] = instance.get('ProcessorFeatures', {})
    options['OptionGroupName'] = [g['OptionGroupName'] for g in instance['OptionGroupMemberships']]
    options['DBSecurityGroups'] = [sg['DBSecurityGroupName'] for sg in instance['DBSecurityGroups'] if sg['Status'] in ['adding', 'active']]
    options['VpcSecurityGroupIds'] = [sg['VpcSecurityGroupId'] for sg in instance['VpcSecurityGroups'] if sg['Status'] in ['adding', 'active']]
    options['DBParameterGroupName'] = [parameter_group['DBParameterGroupName'] for parameter_group in instance['DBParameterGroups']]
    options['EnableIAMDatabaseAuthentication'] = instance['IAMDatabaseAuthenticationEnabled']
    # PerformanceInsightsEnabled is not returned on older RDS instances it seems
    options['EnablePerformanceInsights'] = instance.get('PerformanceInsightsEnabled', False)
    options['NewDBInstanceIdentifier'] = instance['DBInstanceIdentifier']

    # Neither of these are returned via describe_db_instances, so if either is specified during a check_mode run, changed=True
    options['AllowMajorVersionUpgrade'] = None
    options['MasterUserPassword'] = None

    return options


def get_changing_options_with_inconsistent_keys(modify_params, instance, purge_cloudwatch_logs, purge_security_groups):
    changing_params = {}
    current_options = get_current_attributes_with_inconsistent_keys(instance)
    for option in current_options:
        current_option = current_options[option]
        desired_option = modify_params.pop(option, None)
        if desired_option is None:
            continue

        # TODO: allow other purge_option module parameters rather than just checking for things to add
        if isinstance(current_option, list):
            if isinstance(desired_option, list):
                if (
                    set(desired_option) < set(current_option) and
                    option in ('DBSecurityGroups', 'VpcSecurityGroupIds',) and purge_security_groups
                ):
                    changing_params[option] = desired_option
                elif set(desired_option) <= set(current_option):
                    continue
            elif isinstance(desired_option, string_types):
                if desired_option in current_option:
                    continue

        # Current option and desired option are the same - continue loop
        if option != 'ProcessorFeatures' and current_option == desired_option:
            continue

        if option == 'ProcessorFeatures' and current_option == boto3_tag_list_to_ansible_dict(desired_option, 'Name', 'Value'):
            continue

        # Current option and desired option are different - add to changing_params list
        if option == 'ProcessorFeatures' and desired_option == []:
            changing_params['UseDefaultProcessorFeatures'] = True
        elif option == 'CloudwatchLogsExportConfiguration':
            current_option = set(current_option.get('LogTypesToEnable', []))
            desired_option = set(desired_option)
            format_option = {'EnableLogTypes': [], 'DisableLogTypes': []}
            format_option['EnableLogTypes'] = list(desired_option.difference(current_option))
            if purge_cloudwatch_logs:
                format_option['DisableLogTypes'] = list(current_option.difference(desired_option))
            if format_option['EnableLogTypes'] or format_option['DisableLogTypes']:
                changing_params[option] = format_option
        elif option in ('DBSecurityGroups', 'VpcSecurityGroupIds',):
            if purge_security_groups:
                changing_params[option] = desired_option
            else:
                changing_params[option] = list(set(current_option) | set(desired_option))
        else:
            changing_params[option] = desired_option

    return changing_params


def get_changing_options_with_consistent_keys(modify_params, instance):
    changing_params = {}

    for param in modify_params:
        current_option = instance.get('PendingModifiedValues', {}).get(param, None)
        if current_option is None:
            current_option = instance.get(param, None)
        if modify_params[param] != current_option:
            changing_params[param] = modify_params[param]

    return changing_params


def validate_options(client, module, instance):
    state = module.params['state']
    skip_final_snapshot = module.params['skip_final_snapshot']
    snapshot_id = module.params['final_db_snapshot_identifier']
    modified_id = module.params['new_db_instance_identifier']
    engine = module.params['engine']
    tde_options = bool(module.params['tde_credential_password'] or module.params['tde_credential_arn'])
    read_replica = module.params['read_replica']
    creation_source = module.params['creation_source']
    source_instance = module.params['source_db_instance_identifier']
    if module.params['source_region'] is not None:
        same_region = bool(module.params['source_region'] == module.params['region'])
    else:
        same_region = True

    if modified_id:
        modified_instance = get_instance(client, module, modified_id)
    else:
        modified_instance = {}

    if modified_id and instance and modified_instance:
        module.fail_json(msg='A new instance ID {0} was provided but it already exists'.format(modified_id))
    if modified_id and not instance and modified_instance:
        module.fail_json(msg='A new instance ID {0} was provided but the instance to be renamed does not exist'.format(modified_id))
    if state in ('absent', 'terminated') and instance and not skip_final_snapshot and snapshot_id is None:
        module.fail_json(msg='skip_final_snapshot is false but all of the following are missing: final_db_snapshot_identifier')
    if engine is not None and not (engine.startswith('mysql') or engine.startswith('oracle')) and tde_options:
        module.fail_json(msg='TDE is available for MySQL and Oracle DB instances')
    if read_replica is True and not instance and creation_source not in [None, 'instance']:
        module.fail_json(msg='Cannot create a read replica from {0}. You must use a source DB instance'.format(creation_source))
    if read_replica is True and not instance and not source_instance:
        module.fail_json(msg='read_replica is true and the instance does not exist yet but all of the following are missing: source_db_instance_identifier')


def update_instance(client, module, instance, instance_id):
    changed = False

    # Get newly created DB instance
    if not instance:
        instance = get_instance(client, module, instance_id)

    # Check tagging/promoting/rebooting/starting/stopping instance
    changed |= ensure_tags(
        client, module, instance['DBInstanceArn'], instance['Tags'], module.params['tags'], module.params['purge_tags']
    )
    changed |= promote_replication_instance(client, module, instance, module.params['read_replica'])
    changed |= update_instance_state(client, module, instance, module.params['state'])

    return changed


def promote_replication_instance(client, module, instance, read_replica):
    changed = False
    if read_replica is False:
        # 'StatusInfos' only exists when the instance is a read replica
        # See https://awscli.amazonaws.com/v2/documentation/api/latest/reference/rds/describe-db-instances.html
        if bool(instance.get('StatusInfos')):
            try:
                result, changed = call_method(client, module, method_name='promote_read_replica',
                                              parameters={'DBInstanceIdentifier': instance['DBInstanceIdentifier']})
            except is_boto3_error_message('DB Instance is not a read replica'):
                pass
    return changed


def ensure_iam_roles(client, module, instance_id):
    '''
    Ensure specified IAM roles are associated with DB instance

        Parameters:
            client: RDS client
            module: AWSModule
            instance_id: DB's instance ID

        Returns:
            changed (bool): True if changes were successfully made to DB instance's IAM roles; False if not
    '''
    instance = camel_dict_to_snake_dict(get_instance(client, module, instance_id), ignore_list=['Tags', 'ProcessorFeatures'])

    # Ensure engine type supports associating IAM roles
    engine = instance.get('engine')
    if engine not in valid_engines_iam_roles:
        module.fail_json(msg='DB engine {0} is not valid for adding IAM roles. Valid engines are {1}'.format(engine, valid_engines_iam_roles))

    changed = False
    purge_iam_roles = module.params.get('purge_iam_roles')
    target_roles = module.params.get('iam_roles') if module.params.get('iam_roles') else []
    existing_roles = instance.get('associated_roles', [])
    roles_to_add, roles_to_remove = compare_iam_roles(existing_roles, target_roles, purge_iam_roles)
    if bool(roles_to_add or roles_to_remove):
        changed = True
        # Don't update on check_mode
        if module.check_mode:
            module.exit_json(changed=changed, **instance)
        else:
            update_iam_roles(client, module, instance_id, roles_to_add, roles_to_remove)
    return changed


def update_instance_state(client, module, instance, state):
    changed = False
    if state in ['rebooted', 'restarted']:
        changed |= reboot_running_db_instance(client, module, instance)
    if state in ['started', 'running', 'stopped']:
        changed |= start_or_stop_instance(client, module, instance, state)
    return changed


def reboot_running_db_instance(client, module, instance):
    parameters = {'DBInstanceIdentifier': instance['DBInstanceIdentifier']}
    if instance['DBInstanceStatus'] in ['stopped', 'stopping']:
        call_method(client, module, 'start_db_instance', parameters)
    if module.params.get('force_failover') is not None:
        parameters['ForceFailover'] = module.params['force_failover']
    results, changed = call_method(client, module, 'reboot_db_instance', parameters)
    return changed


def start_or_stop_instance(client, module, instance, state):
    changed = False
    parameters = {'DBInstanceIdentifier': instance['DBInstanceIdentifier']}
    if state == 'stopped' and instance['DBInstanceStatus'] not in ['stopping', 'stopped']:
        if module.params['db_snapshot_identifier']:
            parameters['DBSnapshotIdentifier'] = module.params['db_snapshot_identifier']
        result, changed = call_method(client, module, 'stop_db_instance', parameters)
    elif state == 'started' and instance['DBInstanceStatus'] not in ['available', 'starting', 'restarting']:
        result, changed = call_method(client, module, 'start_db_instance', parameters)
    return changed


def main():
    arg_spec = dict(
        state=dict(choices=['present', 'absent', 'terminated', 'running', 'started', 'stopped', 'rebooted', 'restarted'], default='present'),
        creation_source=dict(choices=['snapshot', 's3', 'instance']),
        force_update_password=dict(type='bool', default=False, no_log=False),
        purge_cloudwatch_logs_exports=dict(type='bool', default=True),
        purge_iam_roles=dict(type='bool', default=False),
        purge_tags=dict(type='bool', default=True),
        read_replica=dict(type='bool'),
        wait=dict(type='bool', default=True),
        purge_security_groups=dict(type='bool', default=True),
    )

    parameter_options = dict(
        allocated_storage=dict(type='int'),
        allow_major_version_upgrade=dict(type='bool'),
        apply_immediately=dict(type='bool', default=False),
        auto_minor_version_upgrade=dict(type='bool'),
        availability_zone=dict(aliases=['az', 'zone']),
        backup_retention_period=dict(type='int'),
        ca_certificate_identifier=dict(),
        character_set_name=dict(),
        copy_tags_to_snapshot=dict(type='bool'),
        db_cluster_identifier=dict(aliases=['cluster_id']),
        db_instance_class=dict(aliases=['class', 'instance_type']),
        db_instance_identifier=dict(required=True, aliases=['instance_id', 'id']),
        db_name=dict(),
        db_parameter_group_name=dict(),
        db_security_groups=dict(type='list', elements='str'),
        db_snapshot_identifier=dict(type='str', aliases=['snapshot_identifier', 'snapshot_id']),
        db_subnet_group_name=dict(aliases=['subnet_group']),
        deletion_protection=dict(type='bool'),
        domain=dict(),
        domain_iam_role_name=dict(),
        enable_cloudwatch_logs_exports=dict(type='list', aliases=['cloudwatch_log_exports'], elements='str'),
        enable_iam_database_authentication=dict(type='bool'),
        enable_performance_insights=dict(type='bool'),
        engine=dict(type='str', choices=valid_engines),
        engine_version=dict(),
        final_db_snapshot_identifier=dict(aliases=['final_snapshot_identifier']),
        force_failover=dict(type='bool'),
        iam_roles=dict(type='list', elements='dict'),
        iops=dict(type='int'),
        kms_key_id=dict(),
        license_model=dict(),
        master_user_password=dict(aliases=['password'], no_log=True),
        master_username=dict(aliases=['username']),
        max_allocated_storage=dict(type='int'),
        monitoring_interval=dict(type='int'),
        monitoring_role_arn=dict(),
        multi_az=dict(type='bool'),
        new_db_instance_identifier=dict(aliases=['new_instance_id', 'new_id']),
        option_group_name=dict(),
        performance_insights_kms_key_id=dict(),
        performance_insights_retention_period=dict(type='int'),
        port=dict(type='int'),
        preferred_backup_window=dict(aliases=['backup_window']),
        preferred_maintenance_window=dict(aliases=['maintenance_window']),
        processor_features=dict(type='dict'),
        promotion_tier=dict(),
        publicly_accessible=dict(type='bool'),
        restore_time=dict(),
        s3_bucket_name=dict(),
        s3_ingestion_role_arn=dict(),
        s3_prefix=dict(),
        skip_final_snapshot=dict(type='bool', default=False),
        source_db_instance_identifier=dict(),
        source_engine=dict(choices=['mysql']),
        source_engine_version=dict(),
        source_region=dict(),
        storage_encrypted=dict(type='bool'),
        storage_type=dict(choices=['standard', 'gp2', 'io1']),
        tags=dict(type='dict'),
        tde_credential_arn=dict(aliases=['transparent_data_encryption_arn']),
        tde_credential_password=dict(no_log=True, aliases=['transparent_data_encryption_password']),
        timezone=dict(),
        use_latest_restorable_time=dict(type='bool', aliases=['restore_from_latest']),
        vpc_security_group_ids=dict(type='list', elements='str')
    )
    arg_spec.update(parameter_options)

    required_if = [
        ('engine', 'aurora', ('db_cluster_identifier',)),
        ('engine', 'aurora-mysql', ('db_cluster_identifier',)),
        ('engine', 'aurora-postresql', ('db_cluster_identifier',)),
        ('storage_type', 'io1', ('iops', 'allocated_storage')),
        ('creation_source', 'snapshot', ('db_snapshot_identifier', 'engine')),
        ('creation_source', 's3', (
            's3_bucket_name', 'engine', 'master_username', 'master_user_password',
            'source_engine', 'source_engine_version', 's3_ingestion_role_arn')),
    ]
    mutually_exclusive = [
        ('s3_bucket_name', 'source_db_instance_identifier', 'db_snapshot_identifier'),
        ('use_latest_restorable_time', 'restore_time'),
        ('availability_zone', 'multi_az'),
    ]

    module = AnsibleAWSModule(
        argument_spec=arg_spec,
        required_if=required_if,
        mutually_exclusive=mutually_exclusive,
        supports_check_mode=True
    )

    # Sanitize instance identifiers
    module.params['db_instance_identifier'] = module.params['db_instance_identifier'].lower()
    if module.params['new_db_instance_identifier']:
        module.params['new_db_instance_identifier'] = module.params['new_db_instance_identifier'].lower()

    # Sanitize processor features
    if module.params['processor_features'] is not None:
        module.params['processor_features'] = dict((k, to_text(v)) for k, v in module.params['processor_features'].items())

    # Ensure dates are in lowercase
    if module.params['preferred_maintenance_window']:
        module.params['preferred_maintenance_window'] = module.params['preferred_maintenance_window'].lower()

    # Throw warning regarding case when allow_major_version_upgrade is specified in check_mode
    # describe_rds_instance never returns this value, so on check_mode, it will always return changed=True
    # In non-check mode runs, changed will return the correct value, so no need to warn there.
    # see: amazon.aws.module_util.rds.handle_errors.
    if module.params.get('allow_major_version_upgrade') and module.check_mode:
        module.warn('allow_major_version_upgrade is not returned when describing db instances, so changed will always be `True` on check mode runs.')

    client = module.client('rds')
    changed = False
    state = module.params['state']
    instance_id = module.params['db_instance_identifier']
    instance = get_instance(client, module, instance_id)
    validate_options(client, module, instance)
    method_name = get_rds_method_attribute_name(instance, state, module.params['creation_source'], module.params['read_replica'])

    if method_name:

        # Exit on create/delete if check_mode
        if module.check_mode and method_name in ['create_db_instance', 'delete_db_instance']:
            module.exit_json(changed=True, **camel_dict_to_snake_dict(instance, ignore_list=['Tags', 'ProcessorFeatures']))

        raw_parameters = arg_spec_to_rds_params(dict((k, module.params[k]) for k in module.params if k in parameter_options))
        parameters_to_modify = get_parameters(client, module, raw_parameters, method_name)

        if parameters_to_modify:
            # Exit on check_mode when parameters to modify
            if module.check_mode:
                module.exit_json(changed=True, **camel_dict_to_snake_dict(instance, ignore_list=['Tags', 'ProcessorFeatures']))
            result, changed = call_method(client, module, method_name, parameters_to_modify)

        instance_id = get_final_identifier(method_name, module)

        if state != 'absent':
            # Check tagging/promoting/rebooting/starting/stopping instance
            if not module.check_mode or instance:
                changed |= update_instance(client, module, instance, instance_id)

            # Check IAM roles
            if module.params.get('iam_roles') or module.params.get('purge_iam_roles'):
                changed |= ensure_iam_roles(client, module, instance_id)

        if changed:
            instance = get_instance(client, module, instance_id)
            if state != 'absent' and (instance or not module.check_mode):
                for attempt_to_wait in range(0, 10):
                    instance = get_instance(client, module, instance_id)
                    if instance:
                        break
                    else:
                        sleep(5)

        if state == 'absent' and changed and not module.params['skip_final_snapshot']:
            instance.update(FinalSnapshot=get_final_snapshot(client, module, module.params['final_db_snapshot_identifier']))

    pending_processor_features = None
    if instance.get('PendingModifiedValues', {}).get('ProcessorFeatures'):
        pending_processor_features = instance['PendingModifiedValues'].pop('ProcessorFeatures')
    instance = camel_dict_to_snake_dict(instance, ignore_list=['Tags', 'ProcessorFeatures'])
    if pending_processor_features is not None:
        instance['pending_modified_values']['processor_features'] = pending_processor_features

    module.exit_json(changed=changed, **instance)


if __name__ == '__main__':
    main()
