PostgreSQL testing utility. Both Python 2.7 and 3.3+ are supported.
To install testgres, run:
pip install testgres
We encourage you to use virtualenv for your testing environment.
Note: by default testgres runs
initdb,pg_ctl,psqlprovided byPATH.
There are several ways to specify a custom postgres installation:
- export
PG_CONFIGenvironment variable pointing to thepg_configexecutable; - export
PG_BINenvironment variable pointing to the directory with executable files.
Example:
export PG_BIN=$HOME/pg_10/bin
python my_tests.pyHere is an example of what you can do with testgres:
# create a node with random name, port, etc
with testgres.get_new_node() as node:
# run inidb
node.init()
# start PostgreSQL
node.start()
# execute a query in a default DB
print(node.execute('select 1'))
# ... node stops and its files are about to be removedThere are four API methods for runnig queries:
| Command | Description |
|---|---|
node.psql(query, ...) |
Runs query via psql command and returns tuple (error code, stdout, stderr). |
node.safe_psql(query, ...) |
Same as psql() except that it returns only stdout. If an error occures during the execution, an exception will be thrown. |
node.execute(query, ...) |
Connects to PostgreSQL using psycopg2 or pg8000 (depends on which one is installed in your system) and returns two-dimensional array with data. |
node.connect(dbname, ...) |
Returns connection wrapper (NodeConnection) capable of running several queries within a single transaction. |
The last one is the most powerful: you can use begin(isolation_level), commit() and rollback():
with node.connect() as con:
con.begin('serializable')
print(con.execute('select %s', 1))
con.rollback()By default, cleanup() removes all temporary files (DB files, logs etc) that were created by testgres' API methods.
If you'd like to keep logs, execute configure_testgres(node_cleanup_full=False) before running any tests.
Note: context managers (aka
with) callstop()andcleanup()automatically.
testgres supports python logging,
which means that you can aggregate logs from several nodes into one file:
import logging # write everything to /tmp/testgres.log logging.basicConfig(filename='/tmp/testgres.log') # enable logging, and create two different nodes testgres.configure_testgres(use_python_logging=True) node1 = testgres.get_new_node().init().start() node2 = testgres.get_new_node().init().start() # execute a few queries node1.execute('select 1') node2.execute('select 2') # disable logging testgres.configure_testgres(use_python_logging=False)