豊富なPython のエコシステムでデータ連携が簡単に行えます。 CData Linux/UNIX ODBC Driver for Alfresco とpyodbc module を使って、簡単にAlfresco に連携するPython アプリケーションが構築できます。本記事では、pyodbc のビルトイン機能を使って、Alfresco data に接続し、クエリを実行、表示するかを説明します。
The CData ODBC Drivers are supported in various Red Hat-based and Debian-based systems, including Ubuntu, Debian, RHEL, CentOS, and Fedora. There are also several libraries and packages that are required, many of which may be installed by default, depending on your system. For more information on the supported versions of Linux operating systems and the required libraries, please refer to the "Getting Started" section in the help documentation (installed and found online).
Installing the Driver Manager
Before installing the driver, check that your system has a driver manager. For this article, you will use unixODBC, a free and open source ODBC driver manager that is widely supported.
For Debian-based systems like Ubuntu, you can install unixODBC with the APT package manager:
$ sudo apt-get install unixODBC unixODBC-dev
For systems based on Red Hat Linux, you can install unixODBC with yum or dnf:
$ sudo yum install unixODBC unixODBC-devel
The unixODBC driver manager reads information about drivers from an odbcinst.ini file and about data sources from an odbc.ini
file. You can determine the location of the configuration files on your system by entering the following command into a
terminal:
$ odbcinst -j
The output of the command will display the locations of the configuration files for ODBC data sources and registered ODBC
drivers. User data sources can only be accessed by the user account whose home folder the odbc.ini is located in. System data
sources can be accessed by all users. Below is an example of the output of this command:
DRIVERS............: /etc/odbcinst.ini
SYSTEM DATA SOURCES: /etc/odbc.ini
FILE DATA SOURCES..: /etc/ODBCDataSources
USER DATA SOURCES..: /home/myuser/.odbc.ini
SQLULEN Size.......: 8
SQLLEN Size........: 8
SQLSETPOSIROW Size.: 8
Installing the Driver
You can download the driver in standard package formats: the Debian .deb package format or the .rpm file format. Once you have downloaded the file, you can install the driver from the terminal.
The driver installer registers the driver with unixODBC and creates a system DSN, which can be used later in any
tools or applications that support ODBC connectivity.
For Debian-based systems like Ubuntu, run the following command with sudo or as root:
$ dpkg -i /path/to/package.deb
For Red Hat systems and other systems that support .rpms, run the following command with sudo or as root:
$ rpm -i /path/to/package.rpm
Once the driver is installed, you can list the registered drivers and defined data sources using the unixODBC driver manager:
List the Registered Driver(s)
$ odbcinst -q -d
CData ODBC Driver for Alfresco
...
List the Defined Data Source(s)
$ odbcinst -q -s
CData Alfresco Source
...
To use the CData ODBC Driver for Alfresco with unixODBC, ensure that the driver is configured to use UTF-16. To do so, edit the INI file for the driver (cdata.odbc.alfresco.ini), which can be found in the lib folder in the installation location (typically /opt/cdata/cdata-odbc-driver-for-alfresco), as follows:
cdata.odbc.alfresco.ini
...
[Driver]
DriverManagerEncoding = UTF-16
Modifying the DSN
The driver installation predefines a system DSN. You can modify the DSN by editing the system data sources file (/etc/odbc.ini) and defining the required connection properties. Additionally, you can create user-specific DSNs that will not require root access to modify in $HOME/.odbc.ini.
To connect to Alfresco, the following connection properties must be supplied: User, Password, and InstanceUrl. User and Password correspond to the login credentials that you use to access Alfresco in a web browser. InstanceUrl corresponds to the Alfresco instance you will be querying. For instance, if you expect your queries to hit https://search-demo.dev.alfresco.me/alfresco/api/-default-/public/search/versions/1/sql, you should supply search-demo.dev.alfresco.me for InstanceUrl.
/etc/odbc.ini or $HOME/.odbc.ini
[CData Alfresco Source]
Driver = CData ODBC Driver for Alfresco
Description = My Description
User = MyUsername
Password = MyPassword
Format = Solr
InstanceUrl = api-explorer.alfresco.com
For specific information on using these configuration files, please refer to the help documentation (installed and found online).
You can follow the procedure below to install pyodbc and start accessing Alfresco through Python objects.
pyodbc のインストール
You can use the pip utility to install the module:
pip install pyodbc
Be sure to import with the module with the following:
import pyodbc
Python でのAlfresco Data への接続
You can now connect with an ODBC connection string or a DSN. Below is the syntax for a connection string:
cnxn = pyodbc.connect('DRIVER={CData ODBC Driver for Alfresco};User=MyUsername; Password=MyPassword; Format=Solr; InstanceUrl=api-explorer.alfresco.com;')
Below is the syntax for a DSN:
cnxn = pyodbc.connect('DSN=CData Alfresco Sys;')
Execute SQL to Alfresco
Instantiate a Cursor and use the execute method of the Cursor class to execute any SQL statement.
cursor = cnxn.cursor()
Select
You can use fetchall, fetchone, and fetchmany to retrieve Rows returned from SELECT statements:
import pyodbc
cursor = cnxn.cursor()
cnxn = pyodbc.connect('DSN=CData Alfresco Source;User=MyUser;Password=MyPassword')
cursor.execute("SELECT DBID, Column1 FROM Alfresco WHERE Column2 = 'MyFilter'")
rows = cursor.fetchall()
for row in rows:
print(row.DBID, row.Column1)
You can provide parameterized queries in a sequence or in the argument list:
cursor.execute(
"SELECT DBID, Column1
FROM Alfresco
WHERE Column2 = ?", 'MyFilter',1)
Metadata Discovery
You can use the getinfo method to retrieve data such as information about the data source and the capabilities of the driver. The getinfo method passes through input to the ODBC SQLGetInfo method.
cnxn.getinfo(pyodbc.SQL_DATA_SOURCE_NAME)
You are now ready to build Python apps in Linux/UNIX environments with connectivity to Alfresco data, using the CData ODBC Driver for Alfresco.