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# Cridar scripts de Python des de Basic

És possible cridar scripts de Python des de macros de LibreOffice Basic, i es poden obtenir funcionalitats interessants com ara:

- la possibilitat d'identificació ComputerName i la detecció de l'OSName,

- Les funcions FileLen() del Basic i com.sun.star.ucb.SimpleFileAccess. getSize() de l'API tenen un límit màxim de la mida del fitxer de 2 Gigabytes que es pot superar amb Python,

- Es pot normalitzar com.sun.star.util.PathSettings,

- entre altres funcionalitats.

A reasonable exposure to LibreOffice Basic and to Application Programming Interface (API) features is recommended prior to perform inter-language calls from Basic to Python, to JavaScript or any other script engine.

## Recuperació de scripts en Python

Python scripts can be personal, shared, or embedded in documents. In order to execute them, LibreOffice Basic needs to be provided with Python script locations. Locating com.sun.star.script.provider.XScript interface compliant UNO objects allows the execution of Python scripts:

             Option Explicit

             Public Function GetPythonScript(macro As String, _
                     Optional location As String) As com.sun.star.script.provider.Xscript
                 ''' Pren l'objecte de l'script de Python abans de l'execució
                 ' Arguments:
                 '    macro   : com a «library/module.py$macro» o «module.py$macro»
                 '····location: com a «document», «share», «user» o ENUM(eració)
                 ' Resultat:
                 '    s'ha localitzat el servei com.sun.star.script.provider.XScript de l'UNO'''
                 If IsMissing(location) Then location = "user"
                 Dim mspf As Object ' com.sun.star.script.provider.MasterScriptProviderFactory
                 Dim sp As Object ' compatible amb com.sun.star.script.provider.XScriptProvider
                 Dim uri As String
                 If location="document" Then
                     sp = ThisComponent.getScriptProvider()
                 Else
                     mspf = CreateUNOService("com.sun.star.script.provider.MasterScriptProviderFactory")
                     sp = mspf.createScriptProvider("")
                 End If
                 uri = "vnd.sun.star.script:"& macro &"?language=Python&location="& location
                 GetPythonScript = sp.getScript(uri)
             End Function ' GetPythonScript

## Execució de scripts en Python

The LibreOffice Application Programming Interface (API) Scripting Framework supports inter-language script execution between Python and Basic, or other supported programming languages for that matter. Arguments can be passed back and fourth across calls, providing they represent primitives data types that both languages recognize, and assuming that the Scripting Framework converts them appropriately.

### Sintaxi

workstation_name = script.invoke(Array(), Array(), Array())

opSysName = script.invoke(Array(), in_outs, Array()) ' in_out és una matriu

file_len = script.invoke(Array(systemFilePath), Array(), Array())

normalizedPath = script.invoke(Array(systemFilePath), Array(), Array())

### Exemples de scripts incrustats

Below ComputerName, and GetFilelen routines are calling their Python counterparts, using aforementioned GetPythonScript function. Exception handling is not detailed.

             Option Explicit
             Option Compatible ' S'admeten propietats

             Private scr As Object ' com.sun.star.script.provider.XScript

             Private Property Get ComputerName As String
                 '''Nom de l'estació de treball'''
                 scr = GetPythonScript("Platform.py$computer_name", "document")
                 ComputerName = scr.invoke(Array(), Array(), Array())
             End Property ' ComputerName

             Private Function GetFilelen(systemFilePath As String) As Currency
                 '''Mida del fitxer en bytes'''
                 scr = GetPythonScript("Os/Path.py$get_size", Script.ISEMBEDDED)
                 GetFilelen = scr.invoke(Array(systemFilePath), Array(), Array(),)
             End Function ' GetFilelen

             Private Type _SCRIPT_LOCATION
                 ISEMBEDDED As String ' script del document
                 ISPERSONAL As String ' script d'usuari
                 ISSHARED As String ' macro del LibreOffice
             End Type ' _SCRIPT_LOCATION

             Public Function Script() As Object ' Text enumeration
                 Static enums As _SCRIPT_LOCATION : With enums
                 If .ISEMBEDDED = "" Then
                     .ISEMBEDDED = "document" ' script del document
                     .ISPERSONAL = "user" ' scripts d'usuari
                     .ISSHARED = "share" ' macro del LibreOffice
                 End If : End With ' enums
                 Script = enums
             End Function ' Script

Two different Python modules are called. They can either be embedded in the current document, either be stored on the file system. Argument type checking is skipped for clarity:

- Platform.py

             # -*- coding: utf-8 -*-
             from __future__ import unicode_literals

             import platform

             def computer_name() -> str:
                 return platform.node()

             def OSname() -> str:
                 return platform.system()

- Os/Path.py

             # -*- coding: utf-8 -*-
             from __future__ import unicode_literals

             import os.path

             def get_size(systemFilePath: str) -> str:
                 return str(os.path.getsize(systemFilePath))

             def normalyze(systemPath: str) -> str:
                 return os.path.normpath(systemPath)

### Exemples de scripts personals i compartits

The calling mechanism for personal or shared Python scripts is identical to that of embedded scripts. Library names are mapped to folders. Computing LibreOffice user profile and shared modules system file paths can be performed as detailed in Getting session information. Below OSName, HelloWorld and NormalizePath routines are calling their Python counterparts, using aforementioned GetPythonScript function. Exception handling is not detailed.

             Option Explicit
             Option Compatible ' S'admeten propietats

             Private scr As Object ' com.sun.star.script.provider.XScript

             Private Property Get OSName As String
                 '''El nom d'una plataforma, com ara «Linux», «Darwin» o «Windows»'''
                 scr = GetPythonScript("Platform.py$OSname", Script.ISPERSONAL)
                 OSName = scr.invoke(Array(), Array(), Array())
             End Property ' OSName

             Private Sub HelloWorld()
                 '''exemple de Python compartit al LibreOffice'''
                 scr = GetPythonScript("HelloWorld.py$HelloWorldPython", Script.ISSHARED)
                 scr.invoke(Array(), Array(), Array(),)
             End Sub ' HelloWorld

             Public Function NormalizePath(systemFilePath As String) As String
                 '''Strip superfluous '\..' in path'''
                 scr = GetPythonScript("Os/Path.py$normalyze", "user")
                 NormalizePath = scr.invoke(Array(systemFilePath), Array(), Array())
             End Function ' NormalizePath

## Mòduls estàndards de Python

LibreOffice embedded Python contains many standard libraries to benefit from. They bear a rich feature set, such as but not limited to:

- argparse Parser for command-line options, arguments and sub-commands

- cmath: funcions matemàtiques per a nombres complexos

- csv: lectura i escriptura de fitxers CSV

- datetime: tipus de data i hora genuïns

- json: codificador i descodificador de JSON

- math: funcions matemàtiques

- re: operacions amb expressions regulars

- socket: interfície de xarxes de baix nivell

- sys: paràmetres i funcions específiques del sistema

- unittest i trace: entorn de proves unitàries i seguiment d'execució per a Python

- xml.etree.ElementTree: API d'ElementTree XML

Temes relacionats

Calling Basic Macros from Python

LibreOffice Basic Help

Ajuda dels scripts de Python en el LibreOffice