Segment Mock

A Docker sidecar that mocks the Segment Tracking API to capture and replay analytics calls during integration tests.

This mock is not considered 100% compatibile with Segment's Tracking API, however it will work for recent versions of all of Segment's libraries.

API

This sidecar exposes most of the APIs as api.segment.io, plus the following endpoints:

HTTP Verb	Endpoint	Description
GET	/health	Returns a 200 if the server is available.
GET	/messages	Returns all received messages, and removes them from the internal log.

The above API is subject to change.

Usage

# This will start the sidecar, listening on http://localhost:8765
$ yarn dev

With Docker Compose

Alternatively, you can add this image to your docker-compose.yml:

version: "3"
services:
  snapshotter:
    image: "segment/mock:v0.0.2"
    healthcheck:
      test: "curl --silent --show-error --fail localhost:8765/health || exit 1"
      interval: 1s
      timeout: 1s
      retries: 10
    ports:
      - "8765:8765"

Configuring Segment SDKs

You can update any of the following Segment SDKs to send API requests to this image during integration tests.

analytics-node

const analytics = new SegmentAnalytics('123456', {
  host: 'http://localhost:8765',
})

analytics.js

// This will download the analytics.js snippet via this sidecar, which will
// modify the analytics.js snippet to send API requests to this sidecar.
const ajsCDNSnippet = snippetFn({
  apiKey: '<write key>',
  host: 'localhost:8765',
}).replace('https', 'http')

analytics-android

// TODO!

analytics-ios

SEGAnalyticsConfiguration *configuration = [SEGAnalyticsConfiguration configurationWithWriteKey:@"123456"];

// Customize the requestFactory to point at our sidecar container, which snapshots all analytics calls.
configuration.requestFactory = ^(NSURL *url) {
    NSURLComponents *components = [NSURLComponents componentsWithURL:url resolvingAgainstBaseURL:NO];
    components.scheme = @"http";
    components.host = @"localhost";
    components.port = @8765;
    NSURL *transformedURL = components.URL;
    return [NSMutableURLRequest requestWithURL:transformedURL];
};

[SEGAnalytics setupWithConfiguration:configuration];

Fetching Analytics Calls

To see the set of messages that were fired, you can use the /messages endpoint:

$ curl http://localhost:8765/messages
[{"event":"Hello World","type":"track"}]

Examples

A handful of usage examples exist in the segmentio/typewriter repo.

Releasing to DockerHub

This image is published to DockerHub. You can build and publish new images from master like so:

# First, bump the version in the Makefile, per semver.
# Build the image:
$ yarn build
# Open a PR and merge it to master.
# Then, after checking out the master branch, run the following to publish to DockerHub:
$ yarn release

segmentio/mock