Manage CouchDB: Common management and maintenance

Manage CouchDB is a Couch app ("design document") to do all the common stuff we all need.

It has identical implementations in JavaScript (for clarity and portability) and Erlang (for performance). Both implementations pass the same test suite.

Just drop it in your database (the id is _design/couchdb for JavaScript, and _design/ecouchdb for Erlang) to get several features.

A view of all conflicts

Hit /_view/conflicts to see all conflicts in the database.

• Use ?group_level=1 to get a conflict count for each document
• Use ?reduce=false to get one row per [id,revision] pair.
• Use ?reduce=false&include_docs=true to get every conflicted revision in one big batch.

Some useful rewrites

Manage CouchDB includes some simple rewrites if you want to build from it.

• /_rewrite/_couchdb hits the root CouchDB API
• /_rewrite/_db hits the current database
• /_rewrite/_ddoc hits the manage_couchdb design document itself

An easy validation function

To make a database read-only, edit this design document (e.g. _design/couchdb), and set .access.read_only = true.

When a database is read-only, normal users may not modify any documents. Admins may make changes, but a note is placed in the CouchDB log file.

Refilter: a powerful regular-expression filter function

The filter function, refilter, is great for filtered replication or _changes feeds. Just provide:

• The key in the document
• A regex it should match

Refilter will pass documents that match.

Refilter example

Suppose your documents have a created_at value, with a timestamp.

{ "_id": "example_doc"
, "created_at": "2011-06-19T00:42:20.079Z"
, "value": 23
}

To get documents from June this year and last, drop this document in the _replicator database.

{ "_id": "docs created in June"
, "source": "the_big_database"
, "target": "june"
, "filter": "ecouchdb/refilter"
, "query_params": { "field": "created_at"
                  , "regex": "^(2011|2012)-06"
                  }
}

Test suite

Manage CouchDB uses node-tap. Start a CouchDB in Admin Party at http://localhost:5984 and run the suite via the starter script. The script will do several things:

$ ./test.sh
# Looking for CouchDB
{"couchdb":"Welcome","version":"1.2.0"}

# Configuring CouchDB
"{couch_native_process, start_link, []}"
{"ok":true}
{"ok":true}

# Pushing JavaScript app
Reading dependency tree...
loading js
preprocessor traditional-couchapp/load
loading js/packages/traditional-couchapp
Build complete: 44ms
Uploading...
OK: http://localhost:5984/test_manage_couchdb/_design/couchdb/_rewrite/

# Pushing Erlang app
Reading dependency tree...
loading erlang
preprocessor traditional-couchapp/load
loading erlang/packages/traditional-couchapp
Build complete: 41ms
Uploading...
OK: http://localhost:5984/test_manage_couchdb/_design/ecouchdb

# Running TAP test suite
ok tap/conflicts.js ................................. 101/101
ok tap/lib.js ........................................... 3/3
ok tap/refilter.js ...................................... 6/6
total ............................................... 110/110

ok

License

Manage CouchDB is released under the Apache license, version 2.