introduce Logging support

[stephenplusplus]

Fixes #842

Must Reads

• Introduction to the Cloud Logging API: https://cloud.google.com/logging/docs/api/
• Docs: https://stephenplusplus.github.io/gcloud-node/#/docs/master/logging

To Dos

• Make sure ACLs are properly set for Topics: introduce Logging support #865 (comment)
• Enable Cloud Logging API on System Test Account
• Document createSink.config.filter
• Inherit from Service / ServiceObject
• Support Sink destinations
  • Storage Bucket
  • BigQuery Dataset
  • Pub/Sub Topic
• Docs
  • Readme
  • JSDocs
  • Site
• Tests
  • System
  • Unit
    • Index
    • Log
    • Sink

Preview

// Authenticating on a global-basis. You can also authenticate on a per-API-
// basis (see Authentication section above).
var gcloud = require('gcloud')({
  projectId: 'my-project',
  keyFilename: '/path/to/keyfile.json'
});

var logging = gcloud.logging();

// Create a sink using a Bucket as a destination.
var gcs = gcloud.storage();

logging.createSink('my-new-sink', {
  destination: gcs.bucket('my-sink')
}, function(err, sink) {});

// Write a critical entry to a log.
var syslog = logging.log('syslog');

var resource = {
  type: 'gce_instance',
  labels: {
    zone: 'global',
    instance_id: 3
  }
};

var entry = syslog.entry(resource, {
  delegate: process.env.user
});

syslog.critical(entry, function(err) {});

// Get all entries in your project.
logging.getEntries(function(err, entries) {
  if (!err) {
    // `entries` contains all of the entries from the logs in your project.
  }
});

[stephenplusplus]

@VikramTiwari - your thoughts are most welcome if you have the chance to play around with this!

$ npm install --save stephenplusplus/gcloud-node#spp--logging

[VikramTiwari]

Hey @stephenplusplus I am at Chrome Dev Summit for today and tomorrow, but I will be testing it by the end of week for sure. 👍

[stephenplusplus]

@VikramTiwari awesome! I'll look for you on the feed 🌠

[stephenplusplus]

@jgeewax to prepare for this to merge, can you check that the Logging API is enabled for the Travis project?

[stephenplusplus]

Also, any ideas for getting Travis to auth as a user? Many of our system tests require user-level, non-service account auth.

[callmehiphop]

Thanks @stephenplusplus! Also, thanks for the review @filipjs!