xdump 0.1

Consistent partial database dump utility

XDump

XDump is an utility to make partial consistent dump and load it into the database.

The idea is to provide an ability to specify what to include in the dump via SQL queries. Responsibility for dump integrity lays on the user in this case.

Installation

XDump can be obtained with pip:

$ pip install xdump

Usage example

Making a dump (on production replica for example):

>>> EMPLOYEES_SQL = '''
WITH RECURSIVE employees_cte AS (
  SELECT *
  FROM recent_employees
  UNION
  SELECT E.*
  FROM employees E
  INNER JOIN employees_cte ON (employees_cte.manager_id = E.id)
), recent_employees AS (
  SELECT *
  FROM employees
  ORDER BY id DESC
  LIMIT 2
)
SELECT * FROM employees_cte
'''
>>> from xdump.postgresql import PostgreSQLBackend
>>> backend = PostgreSQLBackend(dbname='app_db', user='prod', password='pass', host='127.0.0.1', port='5432')
>>> backend.dump('/path/to/dump.zip', full_tables=['groups'], partial_tables={'employees': EMPLOYEES_SQL})

Load a dump on you local machine:

from xdump.postgresql import PostgreSQLBackend
>>> backend = PostgreSQLBackend(dbname='app_db', user='local', password='pass', host='127.0.0.1', port='5432')
>>> backend.load('/path/to/dump.zip')

RDBMS support

At the moment only the following are supported:

• PostgreSQL

Django support

Add xdump.extra.django to your INSTALLED_APPS settings:

INSTALLED_APPS = [
   ...,
   'xdump.extra.django',
]

Add XDUMP to your project settings file. It should contain minimum 2 entries:

• FULL_TABLES - a list of tables, that should be fully dumped.

• PARTIAL_TABLES - a dictionary with table_name: select SQL

XDUMP = {
    'FULL_TABLES': ['groups'],
    'PARTIAL_TABLES': {'employees': 'SELECT * FROM employees WHERE id > 100'}
}

Optionally you could use a custom backend:

XDUMP = {
    ...,
    'BACKEND': 'importable.string',
}

Run xdump command:

$ ./manage.py xdump dump.zip

Run xload command:

$ ./manage.py xload dump.zip

Possible options to both commands:

• alias - allows you to choose database config from DATABASES, that is used during the execution;

• backend - importable string, that leads to custom dump backend class.

The following make command could be useful to get a configured dump from production to your local machine:

sync-production:
    ssh -t $(TARGET) "DJANGO_SETTINGS_MODULE=settings.production /path/to/manage.py xdump /tmp/dump.zip"
    scp $(TARGET):/tmp/dump.zip ./dump.zip
    ssh -t $(TARGET) "rm /tmp/dump.zip"
    DJANGO_SETTINGS_MODULE=settings.local $(PYTHON) manage.py xload ./dump.zip

And usage is:

$ make sync-production TARGET=[e-mail] PYTHON=/path/to/python/in/venv

Python support

XDump supports only Python 3.6 at the moment (but the supported versions list will be extended in the future).