cdc-pact-expert-talk

Expert talk repo to contain overall details of the producer and consumer services, plus required docker files to complete the setup for the demo.

Provider service

Code for provider user service can be found here

Consumer service

Code for consumer order service can be found here

Forking the repositories

Forked this, user-service and order-service repositories. See here on how to fork the repositories.

Clone the repositories from your fork.

Update the order-service and user-service pom.xml files to point to your fork as follows and push the changes.

<scm>
    <connection>scm|git:<point-to-your-forked-git-url></connection>
    <url>scm|git:<point-to-your-forked-git-url></url>
    <developerConnection>scm:git:<point-to-your-forked-git-url></developerConnection>
    <tag>HEAD</tag>
</scm>

Use the forked urls in the jenkins jobs as well.

Creating Jenkins image

Build the jenkins docker image using dockerfile with following command

docker build -t cdc-expert-talk/jenkins-cdc -f ./jenkinsDockerfile .

This will create the jenkins build with the suggested plugins. The plugin list is taken from https://github.com/jenkinsci/jenkins/blob/jenkins-2.19.4/core/src/main/resources/jenkins/install/platform-plugins.json

Setting up local environment

To run the scenarios locally, along with these git repositories, a Jenkins server is required to create and run pipeline jobs. A nexus server is required to host consumer and provider's released artifacts. A Pact broker server and Postgres SQL DB to hold the Pact contracts.

Make Jenkins, Pact Broker and Nexus accessible on local

Add following entries in /etc/hosts to allow access to these services

127.0.0.1 mynexus
127.0.0.1 broker_app
127.0.0.1 jenkins

Add settings.xml

Use the settings.xml and add it under the local machines ~/.m2/ directory. This settings file will enable user-service and order-service to resolve artifacts from local nexus repository.

Test setup by running Order service tests locally

Run tests locally with command mvn clean install

Test setup by running User service (make sure to use the right command or avoid running) locally.

Run test locally with command mvn clean install -Dpact.verifier.publishResults=false

Start all services on local.

Make sure you have following settings in the docker preferences -> Advanced:

4 CPUs, 6 GiB RAM, Swap Memory 1 GiB

To start all of these run the docker compose command :

docker-compose up

Verify services are up and running locally:

Verify by hitting following urls in the browser:

Pact Broker: http://broker_app:80

Nexus: http://mynexus:8081/nexus

Jenkins: http://jenkins:8080

Setup Jenkins

Create appropriate maven setup on Jenkins

• Login to Jenkins container with

docker exec -it <JenkinsContainerId> /bin/bash

• Go to /var/jenkins_home and run following commands

mkdir /var/jenkins_home/.m2
mkdir /var/jenkins_home/.m2/repository
cp /tmp/settings.xml .m2/

Create an SSH key for Jenkins and add it in github account

Create ssh key with instructions from https://help.github.com/articles/generating-a-new-ssh-key-and-adding-it-to-the-ssh-agent/#platform-linux

Add ssh key to github account https://help.github.com/articles/adding-a-new-ssh-key-to-your-github-account/#platform-linux

Setup git configuration for jenkins

Setup user and email using following command

git config --global user.name "<Your Name>"
git config --global user.email "<Your email>"

Configure slack global configuration

Use base URL : https://cdc-expert-talk.slack.com/services/hooks/jenkins-ci/

Integration token : <generated>

Disable CSRF (see webhook add section).

Demo scenarios

Consumer - Order service Provider - User service

Order service => call GET /user/{userId} => User service response with user details.

Scenario 1 - Consumer running (passing)

Scenario 2 - Provider passing

• Fail with Provider state implementation missing.

Scenario 3 - Provider failing (fullName instead of name is used in the response).

Scenario 4 - Take consumer and provider to production.

Scenario 5 - Consumer Failing

• Create webhook here first.
• Pact changes
• Start using a new field that is not provided by the provider e.g. primeMemberId.
• fix with the producer change by sending the primeMemberId details as well.

Scenario 6 - Deploy Provider to DEV.

Scenario 7 - Deploy Consumer to DEV - can-i-deploy pass.

Scenario 8 - Deploy consumer to PROD - can-i-deploy fail.

• Fix by deploying the provider to Prod and then promote consumer to PROD.

Scenario 9 - Consumer Passing changes (Pre-verified contracts)(no contract change)

• Some internal implementation change.

Webhook creation

• Edit job configuration which needed to be triggred remotely.
• Enable 'Trigger build remotely' and provide a appropriate token.
• Note down the url provided in the description. Save the configuration.
• Try triggring the job remotely through the url

curl -X POST -u "jenkins_user:jenkins_password" "url"

• You might need to disable CSRF as per the version of jenkins (refer: https://issues.jenkins-ci.org/browse/JENKINS-42200 & https://support.cloudbees.com/hc/en-us/articles/219257077-CSRF-Protection-Explained)
• Once the remote url trigger works for the job.
• Configure a webhook in the Pact Broker by clicking on the create webhook link on pact broken home.
• Send the payload similar to following:

{
  "events": [{
    "name": "contract_content_changed"
  }],
  "request": {
    "method": "POST",
    "url": "http://jenkins:8080/job/user-service/job/user-service-contract-pipeline/build?token=user-service-contract-pipeline-webhook-token",
    "username": "jenkins_user",
    "password": "jenkins_password",
    "headers": {
      "Accept": "application/json"
    }
  }
}

• The output will also provide a link to test the webhook.