couchapp-triggerjob

CouchDB design document to be used with couch-daemon-triggerjob external daemon, to add asynchronous background events to CouchDB.

Installation

1. Install couch-daemon-triggerjob to your CouchDB instance

2. Download this couchapp to your local disk

3. With your preferred Couchapp Deployment tool, upload the downloaded couchapp folder to your CouchDB instance, using app as database name

4. To let the daemon know the path to your couchapp, create the following CouchDB _config parameter:

    section: triggerjob
    parameter: job_path
    value: /app/_design/trigger/_rewrite
   

   If you are going to watch multiple databases, use comma as separator:

    value: /app1/_design/trigger/_rewrite,/app2/_design/trigger/_rewrite
   

5. If your CouchDB instance is admin password protected (no more in Admin Party), create the following _config parameter:

    section: triggerjob
    parameter: job_authorization
    value: adminusername:adminpassword
   

   Don't use your regular admin credentials: create a new pair for daemon-use only:

    section: admins
    parameter: daemon-username
    value: daemon-password
   

How to Use

You can monitor daemon status and messages using the CouchDB _log handler, or using the Log feature within Fauxton administration interface.

Examples

Have a look at Smileupps for some trigger use case examples

How it works

This couchapp works by:

• forwarding daemon requests from /follow/changes to a filtered CouchDB changes handler: used by the daemon to continuously listen for new triggers
• forwarding daemon requests from /trigger to an update function updates/trigger.js: this lets the daemon update your CouchDB database, with trigger results and execution status
• forwarding any other daemon request to your main couchapp application stored in _design/app: this lets you implement your own application behaviour. For secure and easy couchapp development, you can follow the action-based write approach described within the Chatty couchdb tutorial.