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GitHub Actions Pipeline

Tracetest is a testing tool based on OpenTelemetry that allows you to test your distributed application. It allows you to use data from distributed traces generated by OpenTelemetry to validate and assert if your application has the desired behavior defined by your test definitions.

GitHub Actions Workflow for Running Tracetest tests against a sample Node.js app with OpenTelemetry

This is a simple quick start on how to configure GitHub Actions to run Tracetest tests against a Node.js app thats uses OpenTelemetry instrumentation with traces. This example includes manual instrumentation and a sample bookstore array that simulates fetching data from a database.

GitHub Actions Workflow

This sample has two workflows. The workflows have one job and a total of 6 steps. The steps are:

  1. Checking out the repo code
  2. Starting the sample app with Docker Compose
  3. Installing the Tracetest CLI
  4. Configuring the Tracetest CLI
  5. Running tests with the Tracetest CLI
  6. Stop Docker Compose

The first workflow triggers a pre-merge and merge test run.

# start-and-test-on-main.yaml

name: Docker Compose Start and Test on push and PR to main

on:
push:
branches: [ "main" ]
pull_request:
branches: [ "main" ]

jobs:
start-and-test:
timeout-minutes: 10
runs-on: ubuntu-latest
steps:
- name: Checkout
uses: actions/checkout@v1

- name: Start containers
run: docker compose -f "docker-compose.yaml" -f "tracetest/docker-compose.yaml" up -d --build

- name: Install Tracetest CLI
shell: bash
run: curl -L https://raw.githubusercontent.com/kubeshop/tracetest/main/install-cli.sh | bash

- name: Configure Tracetest CLI
run: tracetest configure -g --server-url http://localhost:11633

- name: Run tests via the Tracetest CLI
run: |
tracetest run test -f ./tracetest/tests/test-api.yaml
tracetest run test -f ./tracetest/tests/test-api-and-av.yaml
tracetest run testsuite -f ./tracetest/tests/testsuite-api.yaml

- name: Stop containers
if: always()
run: docker compose -f "docker-compose.yaml" -f "tracetest/docker-compose.yaml" down -v

And, the other is a scheduled test run.

# start-and-test-on-schedule.yaml

name: Docker Compose Start and Test Every Hour

on:
schedule:
- cron: '0 * * * *'

jobs:
start-and-test:
timeout-minutes: 10
runs-on: ubuntu-latest
steps:
- name: Checkout
uses: actions/checkout@v1

- name: Start containers
run: docker compose -f "docker-compose.yaml" -f "tracetest/docker-compose.yaml" up -d --build

- name: Install Tracetest CLI
shell: bash
run: curl -L https://raw.githubusercontent.com/kubeshop/tracetest/main/install-cli.sh | bash

- name: Configure Tracetest CLI
run: tracetest configure -g --server-url http://localhost:11633

- name: Run tests via the Tracetest CLI
run: |
tracetest run test -f ./tracetest/tests/test-api.yaml
tracetest run test -f ./tracetest/tests/test-api-and-av.yaml
tracetest run testsuite -f ./tracetest/tests/testsuite-api.yaml

- name: Stop containers
if: always()
run: docker compose -f "docker-compose.yaml" -f "tracetest/docker-compose.yaml" down -v

Project structure

Let's first explain how the example app is built. It uses Docker Compose, and contains two distinct docker-compose.yaml files. As you see in the GitHub Actions Workflow, all services in the example app are started with Docker Compose.

1. Node.js app

The docker-compose.yaml file and Dockerfile in the root directory are for the Node.js app.

2. Tracetest

The docker-compose.yaml file, collector.config.yaml, tracetest-provision.yaml, and tracetest.config.yaml in the tracetest directory are for the setting up Tracetest and the OpenTelemetry Collector.

The tracetest directory is self-contained and will run all the prerequisites for enabling OpenTelemetry traces and trace-based testing with Tracetest.

Docker Compose Network

All services in the docker-compose.yaml are on the same network and will be reachable by hostname from within other services. E.g. tracetest:4317 in the collector.config.yaml will map to the tracetest service, where the port 4317 is the port where Tracetest accepts traces.

Node.js app

The Node.js app is a simple Express app with two microservices, contained in the app.js and availability.js files.

The OpenTelemetry tracing is contained in the tracing.otel.grpc.js or tracing.otel.http.js files, respectively. Traces will be sent to the OpenTelemetry Collector.

Here's the content of the tracing.otel.grpc.js file:

const opentelemetry = require("@opentelemetry/sdk-node");
const {
getNodeAutoInstrumentations,
} = require("@opentelemetry/auto-instrumentations-node");
const {
OTLPTraceExporter,
} = require("@opentelemetry/exporter-trace-otlp-grpc");
const { Resource } = require("@opentelemetry/resources");
const {
SemanticResourceAttributes,
} = require("@opentelemetry/semantic-conventions");
const { NodeTracerProvider } = require("@opentelemetry/sdk-trace-node");
const { BatchSpanProcessor } = require("@opentelemetry/sdk-trace-base");

const resource = Resource.default().merge(
new Resource({
[SemanticResourceAttributes.SERVICE_NAME]:
"quick-start-nodejs-manual-instrumentation",
[SemanticResourceAttributes.SERVICE_VERSION]: "0.0.1",
})
);

const provider = new NodeTracerProvider({ resource: resource });
const exporter = new OTLPTraceExporter({ url: "http://otel-collector:4317" });
const processor = new BatchSpanProcessor(exporter);
provider.addSpanProcessor(processor);
provider.register();

const sdk = new opentelemetry.NodeSDK({
traceExporter: exporter,
instrumentations: [getNodeAutoInstrumentations()],
serviceName: "quick-start-nodejs-manual-instrumentation",
});
sdk.start();

Depending on which of these you choose, traces will be sent to either the grpc or http endpoint.

The hostnames and ports for these are:

  • GRPC: http://otel-collector:4317
  • HTTP: http://otel-collector:4318/v1/traces

Enabling the tracer is done by preloading the trace file.

node -r ./tracing.otel.grpc.js app.js

In the package.json you will see two npm script for running the respective tracers alongside the app.js.

"scripts": {
"app-with-grpc-tracer": "node -r ./tracing.otel.grpc.js app.js",
"app-with-http-tracer": "node -r ./tracing.otel.http.js app.js",
"availability-with-grpc-tracer": "node -r ./tracing.otel.grpc.js availability.js",
"availability-with-http-tracer": "node -r ./tracing.otel.http.js availability.js"
},

To start the app.js Express server you run this command.

npm run app-with-grpc-tracer
# or
npm run app-with-http-tracer

To start the availability.js Express server you run this command.

npm run availability-with-grpc-tracer
# or
npm run availability-with-http-tracer

As you can see the Dockerfile does not have a CMD section.

FROM node:slim
WORKDIR /usr/src/app
COPY package*.json ./
RUN npm install
COPY . .
EXPOSE 8080

Instead, the docker-compose.yaml contains the CMD section for both services.

version: "3"
services:
app:
image: quick-start-nodejs
build: .
command: npm run app-with-grpc-tracer
ports:
- "8080:8080"
availability:
image: quick-start-nodejs-availability
build: .
command: npm run availability-with-grpc-tracer
ports:
- "8080"

To start it, run this command:

docker compose build # optional if you haven't already built the image
docker compose up

This will start the Node.js app. But, you're not sending the traces anywhere.

Let's fix this by configuring Tracetest and OpenTelemetry Collector.

Tracetest

The docker-compose.yaml in the tracetest directory is configured with three services.

  • Postgres - Postgres is a prerequisite for Tracetest to work. It stores trace data when running the trace-based tests.
  • OpenTelemetry Collector - A vendor-agnostic implementation of how to receive, process and export telemetry data.
  • Tracetest - Trace-based testing that generates end-to-end tests automatically from traces.
version: "3"
services:
tracetest:
image: kubeshop/tracetest:latest
platform: linux/amd64
volumes:
- type: bind
source: ./tracetest/tracetest-config.yaml
target: /app/tracetest.yaml
- type: bind
source: ./tracetest/tracetest-provision.yaml
target: /app/provisioning.yaml
ports:
- 11633:11633
command: --provisioning-file /app/provisioning.yaml
depends_on:
postgres:
condition: service_healthy
otel-collector:
condition: service_started
healthcheck:
test: ["CMD", "wget", "--spider", "localhost:11633"]
interval: 1s
timeout: 3s
retries: 60
environment:
TRACETEST_DEV: ${TRACETEST_DEV}

postgres:
image: postgres:14
environment:
POSTGRES_PASSWORD: postgres
POSTGRES_USER: postgres
healthcheck:
test: pg_isready -U "$$POSTGRES_USER" -d "$$POSTGRES_DB"
interval: 1s
timeout: 5s
retries: 60

otel-collector:
image: otel/opentelemetry-collector-contrib:0.59.0
command:
- "--config"
- "/otel-local-config.yaml"
volumes:
- ./tracetest/collector.config.yaml:/otel-local-config.yaml

Tracetest depends on both Postgres and the OpenTelemetry Collector. Both Tracetest and the OpenTelemetry Collector require config files to be loaded via a volume. The volumes are mapped from the root directory into the tracetest directory and the respective config files.

The tracetest-config.yaml file contains the basic setup of connecting Tracetest to the Postgres instance.

postgres:
host: postgres
user: postgres
password: postgres
port: 5432
dbname: postgres
params: sslmode=disable

The tracetest-provision.yaml file provisions the trace data store and polling to store in the Postgres database. The data store is set to OTLP meaning the traces will be stored in Tracetest itself.

---
type: PollingProfile
spec:
name: Default
strategy: periodic
default: true
periodic:
retryDelay: 5s
timeout: 10m

---
type: DataStore
spec:
name: OpenTelemetry Collector
type: otlp
default: true

But how are traces sent to Tracetest?

The collector.config.yaml explains that. It receives traces via either grpc or http. Then, exports them to Tracetest's otlp endpoint tracetest:4317.

receivers:
otlp:
protocols:
grpc:
http:

processors:
batch:
timeout: 100ms

exporters:
logging:
loglevel: debug
otlp/1:
endpoint: tracetest:4317
# Send traces to Tracetest.
# Read more in docs here: https://docs.tracetest.io/configuration/connecting-to-data-stores/opentelemetry-collector
tls:
insecure: true

service:
pipelines:
traces/1:
receivers: [otlp]
processors: [batch]
exporters: [otlp/1]

Run both the Node.js app and Tracetest

To start both the Node.js services and Tracetest we will run this command:

docker-compose -f docker-compose.yaml -f tracetest/docker-compose.yaml up # add --build if the images are not built already

This will start your Tracetest instance on http://localhost:11633/.

Run Tracetest tests with the Tracetest CLI

First, install the CLI. Then, configure the CLI:

tracetest configure --server-url http://localhost:11633

Once configured, you can run a test against the Tracetest instance via the terminal.

Check out the test-api.yaml file in the ./tracetest/tests directory.

type: Test
spec:
id: W656Q0c4g
name: Books List
description: List of books
trigger:
type: http
httpRequest:
url: http://app:8080/books
method: GET
headers:
- key: Content-Type
value: application/json
specs:
- selector: span[tracetest.span.type="http" name="GET /books" http.target="/books" http.method="GET"]
assertions:
- attr:http.status_code = 200
- selector: span[tracetest.span.type="general" name="Books List"]
assertions:
- attr:books.list.count = 4

To run the test, run this command in the terminal:

tracetest run test -f ./tracetest/tests/test-api.yaml

This test will fail just like the sample above due to the attr:books.list.count = 4 assertion.

✘ http://app:8080 (http://localhost:11633/test/W656Q0c4g/run/5/test)
✔ span[tracetest.span.type="http" name="GET /books" http.target="/books" http.method="GET"]
✔ #994c63e0ea35e632
✔ attr:http.status_code = 200 (200)
✘ span[tracetest.span.type="general" name="Books List"]
✘ #5ab1856c32b0d5c8
✘ attr:books.list.count = 4 (3) (http://localhost:11633/test/W656Q0c4g/run/5/test?selectedAssertion=1&selectedSpan=5ab1856c32b0d5c8)

The tests will pass if you change the assertion to:

attr: books.list.count = 3;

There are two more files in the ./tracetest/tests directory that we use in the GitHub Actions Workflow.

The test test-api-and-av.yaml also includes assertions for the availability service.

# ./tracetest/tests/test-api-and-av.yaml

type: Test
spec:
id: phAZcrT4B
name: Books list with availability
description: Testing the books list and availability check
trigger:
type: http
httpRequest:
url: http://app:8080/books
method: GET
headers:
- key: Content-Type
value: application/json
specs:
- selector: span[tracetest.span.type="http" name="GET /books" http.target="/books"
http.method="GET"]
assertions:
- attr:tracetest.span.duration < 500ms
- selector: span[tracetest.span.type="general" name="Books List"]
assertions:
- attr:books.list.count = 3
- selector: span[tracetest.span.type="http" name="GET /availability/:bookId" http.method="GET"]
assertions:
- attr:http.host = "availability:8080"
- selector: span[tracetest.span.type="general" name="Availablity check"]
assertions:
- attr:isAvailable = "true"

The testsuite testsuite-api.yaml will run both the tests above.

# ./tracetest/tests/testsuite-api.yaml

type: TestSuite
spec:
id: 3YIB7rPVg
name: All Tests for the Books List API
steps:
- phAZcrT4W
- phAZcrT4B

Feel free to check out our docs, and join our Slack Community for more info!