mongostat-fdw 0.0.1

mongo databases and collections statistics fdw for postgresql

Mongo database and collection statistics foreign data wrapper for PostgreSQL written in python.

dependencies

• pymongo

• multicorn

installation

1. install python module

• from sources (bitbucket)

  $ git clone https://bitbucket.org/olshevskiy87/mongostat_fdw.git
  $ cd mongostat_fdw
  $ python setup.py install

• using pip

  $ pip install mongostat_fdw

2. create extension “multicorn” in postgresql (e.g. using psql)

   $$ create extension multicorn;

3. create foreign servers

   $$ CREATE SERVER mongostat_fdw_db
      FOREIGN DATA WRAPPER multicorn
      OPTIONS (
          wrapper 'mongostat_fdw.MongoDBStatFDW'
      );

   $$ CREATE SERVER mongostat_fdw_coll
      FOREIGN DATA WRAPPER multicorn
      OPTIONS (
          wrapper 'mongostat_fdw.MongoCollStatFDW'
      );

4. create foreign tables

   $$ CREATE FOREIGN TABLE mongo_db_stat (
       "avgObjSize" NUMERIC,
       collections INT,
       "dataFileVersion" JSONB, -- for Postgres 9.4+ or JSON, or (at least) TEXT
       "extentFreeList" JSONB,  -- Mongo 3.0.0+
       "dataSize" NUMERIC,
       db TEXT,
       "fileSize" NUMERIC,
       "indexSize" NUMERIC,
       indexes INT,
       "nsSizeMB" BIGINT,
       "numExtents" INT,
       objects INT,
       ok NUMERIC,
       "storageSize" NUMERIC,
       "extentFreeList" JSONB   -- for Postgres 9.4+ or JSON, or (at least) TEXT
   ) SERVER mongostat_fdw_db OPTIONS (
       -- uri 'mongodb://127.0.0.1:27017',
       host '127.0.0.1',
       port '27017',
       db 'test'
   );

   $$ CREATE FOREIGN TABLE mongo_coll_stat (
       "avgObjSize" NUMERIC,
       count INT,
       "indexSize" JSONB,
       "lastExtentSize" NUMERIC,
       nindexes INT,
       ns TEXT,
       "numExtents" INT,
       ok NUMERIC,
       "paddingFactor" NUMERIC,
       size NUMERIC,
       "storageSize" NUMERIC,
       "systemFlags" INT,
       "totalIndexSize" NUMERIC,
       "userFlags" INT
   ) SERVER mongostat_fdw_coll OPTIONS (
       db 'test'
   );

usage

• get “test” database statistics

$$ select db, "fileSize", "dataSize", "avgObjSize", indexes, "dataFileVersion"
   from mongo_db_stat;

  db   | fileSize | dataSize |  avgObjSize   | indexes |     dataFileVersion
-------+----------+----------+---------------+---------+--------------------------
 local | 67108864 |     2840 | 405.714285714 |       1 | {"major": 4, "minor": 5}
 admin |        0 |        0 |           0.0 |       0 | {}
(2 rows)

• get “test” database collections statistics

$$ select ns as tbl_name, size, "storageSize", count
   from mongo_coll_stat;

      tbl_name       | size | storageSize | count
---------------------+------+-------------+-------
 test.system.indexes |   72 |        4096 |     1
 test.test_coll      |  344 |        4096 |     7
(2 rows)

external links

• PostgreSQL foreign data wrappers

• Multicorn - Postgres extension that allows to make FDW with python language

• MongoDB - a high performance document-oriented DBMS with automatic scaling

• MongoDB dbStats command

• pymongo - python distribution for working with MongoDB

license

Copyright (c) 2016 Dmitriy Olshevskiy. MIT LICENSE.

See LICENSE.txt for details.