Bottle-SQLite¶
SQLite is a self-contained SQL database engine that runs locally and does not require any additional server software or setup. The sqlite3 module is part of the Python standard library and already installed on most systems. It it very useful for prototyping database-driven applications that are later ported to larger databases such as PostgreSQL or MySQL.
This plugin simplifies the use of sqlite databases in your Bottle applications.
Once installed, all you have to do is to add a db
keyword argument
(configurable) to route callbacks that need a database connection.
Installation¶
Install with one of the following commands:
$ pip install bottle-sqlite
$ easy_install bottle-sqlite
or download the latest version from github:
$ git clone git://github.com/defnull/bottle.git
$ cd bottle/plugins/sqlite
$ python setup.py install
Usage¶
Once installed to an application, the plugin passes an open
sqlite3.Connection
instance to all routes that require a db
keyword
argument:
import bottle
app = bottle.Bottle()
plugin = bottle.ext.sqlite.Plugin(dbfile='/tmp/test.db')
app.install(plugin)
@app.route('/show/:item')
def show(item, db):
row = db.execute('SELECT * from items where name=?', item).fetchone()
if row:
return template('showitem', page=row)
return HTTPError(404, "Page not found")
Routes that do not expect a db
keyword argument are not affected.
The connection handle is configured so that sqlite3.Row
objects can be
accessed both by index (like tuples) and case-insensitively by name. At the end of
the request cycle, outstanding transactions are committed and the connection is
closed automatically. If an error occurs, any changes to the database since the
last commit are rolled back to keep the database in a consistent state.
Configuration¶
The following configuration options exist for the plugin class:
- dbfile: Database filename (default: in-memory database).
- keyword: The keyword argument name that triggers the plugin (default: ‘db’).
- autocommit: Whether or not to commit outstanding transactions at the end of the request cycle (default: True).
- dictrows: Whether or not to support dict-like access to row objects (default: True).
You can override each of these values on a per-route basis:
@app.route('/cache/:item', sqlite={'dbfile': ':memory:'})
def cache(item, db):
...
or install two plugins with different keyword
settings to the same application:
app = bottle.Bottle()
test_db = bottle.ext.sqlite.Plugin(dbfile='/tmp/test.db')
cache_db = bottle.ext.sqlite.Plugin(dbfile=':memory:', keyword='cache')
app.install(test_db)
app.install(cache_db)
@app.route('/show/:item')
def show(item, db):
...
@app.route('/cache/:item')
def cache(item, cache):
...