rowjay/pubsub-toolkit

A toolkit of node.js scripts to manage Google Cloud PubSub topics from Google Cloud Functions

pubsub-toolkit

A toolkit of node.js scripts to manage Google cloud PubSub topics

Setup local development environment

1. Get the relevant binary or source code from the node.js download page and install. Check node and node package manager version with node -v and npm -v respectively.
2. Clone this repository and cd into it: git clone git@github.com:rowjay/pubsub-toolkit.git && cd pubsub-toolkit
3. Install dependencies: npm install

Pubsub

Message format

{
  "data": string,
  "attributes": {
    string: string,
    ...
  },
  "messageId": string,
  "publishTime": string,
}

Functions

1. Create storage bucket for functions
2. Write index.js, package.json, and config.json files
3. Deploy function to be executed (in index.js) by upload, storage, or repo. Note this is configured with json files.

Functions can be triggered by HTTP, Pubsub message, or Storage events. Background functions take 'event' and 'callback' parameters

Event

The event is a javascript object

{
  'eventId': 'unique ID',
  'timestamp': 'ISO 8601 created datetime',
  'eventType': 'type of event',
  'resource': 'what emitted this event'
  'data': {
    'key': 'value'
  }
}

Callback

Signals completion

// Success
callback(null, 'Win!');
// Failure
callback(new Error('oops'));

Manual Triggers

Direct

Eg.

DATA=$(printf 'Example'|base64) && gcloud beta functions call functionName --data '{"x":"'$DATA'"}'

Pubsub

To manually invoke pubsub triggered function:

gcloud beta functions call functionName --data '{"data": "payload", "attributes": {"key0": "value0"}}'

Links

Pubsub message format Functions events and callbacks PubSub API client node.js