pachelbel

pachelbel

pachelbel is a query performance monitor for the express framework using the node-pg driver for PostgreSQL. It works by proxying elements of the pg driver to store query statistics in an in-memory SQLite database and providing a statistics dashboard in the host application.

Usage

pachelbel requires the pg module as a peer dependency. Ensure that it is available if you are using a framework or driver wrapper such as MassiveJS.

In your app.js, require pachelbel and wire it to a route. pachelbel must be loaded before pg in order to proxy the driver correctly.

if (process.env.NODE_ENV !== 'production') {
  app.use('/pachelbel', require('pachelbel'));
}

Note that pachelbel is not, by default, wired into any authentication system you may have and will therefore happily give query statistics and prepared statement text to anyone and everyone unless you take your own precautions to secure it.

Customizing thresholds

By default, queries taking 100ms or more are considered "bad" (yellow), and queries taking 500ms or more "worse" (red). To customize these, change pachelbel's thresholds object before the app.use directive:

pachelbel.thresholds = { bad: 200, worse: 750 };