In previous articles we have seen how to setup a Jenkins CI system on top of docker and leverage docker in order to create a continuous integration pipeline. As part of that we used docker to create a centrally managed build environment which can be rolled out to any number of machines. We then setup the environment in Jenkins CI and automated the continuous building, packaging and testing of the source.

In this article we will take the pipeline further (shown below) and see how we can continuously deploy the project to a long-running testing environment. This will allow manual human testing of the code in addition to automated acceptance testing. This environment will also allow you to get your customers’ or QA’s eyes on the latest changes before they hit production. Further, this will give you a good idea of how to build and deploy to production environments which we will cover in the next article. You can download the entire series in our eBook \”Continuous Integration and Deployment with Docker and Rancher.\”

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Creating long running application environments with Docker and Rancher

After we’ve built and tested our application, we can now deploy it to a long running, potentially externally facing environment. This environment will allow Quality Assurance (QA) or customers to see and test the latest changes before they make their way to production. This environment is an important step on the road to production as it allows us to unearth bugs that are only seen with real-world use and not automated integration tests. We normally call this environment the QA or Integration environment. Like our previous article, we’ll be using the go-auth component of our go-messenger project to demonstrate how to create a test environment. We’ll go through the steps below for creating our integration environment:

Create an Integration environment in Rancher Define Docker Compose and Rancher Compose templates Create application stack with Rancher Manage DNS records with Rancher and AWS Route53 Add support for HTTPS

Create an Integration environment in Rancher

In the Rancher UI, go to the top right corner and select Manage Environments and Add Environment. In the resulting screen (shown below) add the Name (Integration) and optionally a description for each of the environments. You also need to select a list of users and organizations that have access to the environments.

Once you have your environment setup, select the Integration environment from the drop down in the top left corner of the screen. We can now create the application stack for the integration environment. Also from the menu in the top right corner select API & Keys and Add API Key. This will load a pop-up screen which allows you to create a named API Key pair. We need the key in subsequent steps to to use Rancher Compose to create our test environments. We will create key pair named JenkinsKey to run rancher compose from our Jenkins instance. Copy the key and secret for use later as you will not be shown these values again. Note that API keys are specific to the environment and hence you will have to create a new key for each environment.

Define Docker Compose and Rancher Compose templates

In our [previous article] we created a docker compose template to define the container types required for our project. The compose template (docker-compose.yml) is shown below. We will be using the same docker compose template as before but with the addition of auth-lb service. This will add a load-balancer in front of our go-auth service and split traffic across all the containers running the service. Having a load balancer in front of our service is essential to insure availability and scalability, as it continues to serve traffic even if one (or more) of our service containers die. Additionally, it also spreads the load on multiple containers which may be running on multiple hosts.

mysql-master: image: mysql environment: MYSQL_ROOT_PASSWORD: rootpass MYSQL_DATABASE: messenger MYSQL_USER: messenger MYSQL_PASSWORD: messenger expose: - "3306" stdin_open: true tty: true auth-service: tty: true command: - --db-host - mysql-master - -p - '9000' image: usman/go-auth:${auth_version} links: - mysql-master:mysql-master stdin_open: true auth-lb: ports: - '9000' expose: - 9090:9000 tty: true image: rancher/load-balancer-service links: - auth-service:auth-service stdin_open: true

[We are using Rancher Compose to launch the environment in a multi-host environment, this more closely mirrors production and also allows us to test integration with various services, e.g. Rancher and Docker Hub etc. Unlike our previous docker compose based environment which was explicitly designed to be independent of external services and launched on the CI server itself without pushing images to dockerhub. ]

Now that we are going to use Rancher compose to launch a multi-host test environment instead of docker compose, we also need to define a rancher compose template. Create a a file called rancher-compose.yml and add the following content. In this file we are defining that we need two containers of the auth service, one container running the database and another running the load-balancer container.

auth-service: scale: 2 mysql-master: scale: 1 auth-lb scale: 1

Next we will add a health check to the auth-service to make sure that we detect when containers are up and able to respond to requests. For this we will use the /health URI of the go-auth service. The auth-service section of rancher-compose.yml should now look something like this:

auth-service scale: 1 health_check: port: 9000 interval: 2000 unhealthy_threshold: 3 request_line: GET /health HTTP/1.0 healthy_threshold: 2 response_timeout: 2000

We are defining a health check on port 9000 of the service container which is run every 2 seconds (2000 milliseconds). The check makes a http request to the /health URI and 3 consecutive failed checks mark a container as unhealthy whereas 2 consecutive successes mark a container as healthy.

Create application stack with Rancher Compose

Now that we have our template defined we can use Rancher compose to launch our environment. To follow along, simply checkout the go-messenger project and download the rancher-compose CLI from rancher UI. To setup rancher-compose on your development machine, follow the instructions. Once you have rancher-compose setup you can use the create command shown below to setup your integration environment.

git clone https://github.com/usmanismail/go-messenger.git cd go-messenger/deploy #replace rancher-compose with the latest version you downloaded from rancher UI ./rancher-compose --project-name messenger-int \ --url http://YOUR_RANCHER_SERVER:PORT/v1/ \ --access-key <API_KEY> \ --secret-key <SECRET_KEY> \ --verbose create

In the UI, you should now be able to see the stack and services for your project. Note that \“create\” command only creates the stack and doesn’t start services. You can either start the services from the UI or use the rancher-compose start command to start all the services.

Let’s use rancher-compose again to start the services:

./rancher-compose --project-name messenger-int \ --url http://YOUR_RANCHER_SERVER:PORT/v1/ \ --access-key <API_KEY> \ --secret-key <SECRET_KEY> \ --verbose start

To make sure everything is working, head over to the public IP for the host running the \“auth-lb\” service and create a user using the command shown below. You should get a 200 OK. Repeating the above request should return a 409 error indicating a conflict with an existing user in the database. At this point we have a basic integration environment for our application which is intended to be a long running environment.

curl -i -silent -X PUT -d userid=<TEST_USERNAME> -d password=<TEST_PASS> <HOST_IP_FOR_AUTH_LB>:9000/user

Manage DNS records with Rancher and AWS Route53

Since this environment is meant to be long running and externally facing, we are going to be using DNS entries and HTTPS. This allows us to distribute the application outside corporate firewalls securely and also allows more casual users to rely on persistent DNS rather than IPs which may change. You may use a DNS provider of your choice, however, we are going to illustrate how to setup DNS entries in Amazon Route53. To do so go to AWS Console > Route 53 > Hosted Zones and Create Hosted Zone. In the hosted zone you will have to specify a domain name of your choice e.g. gomessegner.com. While you are in the AWS console you can also create a user for Rancher to use to make Route53 updates. Go to AWS Console > IAMS > Users and select Create New Users. Keep the the Access Key and Secret Key of this user handy as you will need a little later on. Once you have created the user account you must add the AmazonRoute53FullAccess policy to the user so that it can make updates to route53.

Now that we have our Hosted Zone and IAMs user setup we can add the Route53 integration to our Rancher Server. The detailed instructions on how to do so can be found here. In short you need to browse to Applications > Catalog on your rancher server and select Route 53 DNS. You will be asked to specify the Hosted Zone that you setup earlier as well as the AWS Access and Secert Keys for you Rancher IAMs user with Route53 access. Once you enter the required information and click create, you should see new stack created in your environment with a service called route53.

This service will listen for Rancher events and catch any load balancer instance launches and terminations. Using this information it will automatically create DNS entries for all the Hosts on which your loadbalancer containers are running. The DNS entries are of the form [Loadbalancer].[stack].[environment].[domain], e.g. goauth.integration.testing.gomessenger.com. As more containers are launched and taken down on your various Rancher compute nodes the Route53 service will keep your DNS records consistent. This is essential for our integration test environments because as we will see later we need to relaunch the environment containers in order to push updates as part of continuous deployment. With Route53 DNS integration we do not have to worry about getting the latest hostnames to our clients and testers.

Add support for HTTPS

Now that we have DNS records for our environment it is a good idea to support HTTPS. To do that, first, we need an SSL certificate for our domain. You can purchase a root SSL certificate for your domain from one the many trusted certificate authorities such as Comodo. If you don’t have a certificate you can generate a self-signed certificate to complete the setup and replace it with a trusted one at a later time. The implication of a self-signed certificate is that any user will get a \“This connection is untusted\” warnings in browsers, however, the communication is still encrypted. In order to generate the self-signed certificate you will first need to generate the ssl key which you can do using the genrsa command of openssl. Then you can use the key file to generate the certificate using the req command. The steps to do so are listed below. Its also a good idea to print and store the sha256 finger print of the certificate so that you can manually ensure that the same certificate is presented to you when making HTTPS requests. In the absence of a trusted certificate manually matching fingerprints is the only way to ensure that there aren’t any man-in-the-middle attacks.

openssl genrsa -out integration.gomessenger.com.key 2048 openssl req -new -x509 \ -key integration.gomessenger.com.key \ -out integration.gomessenger.com.crt \ -days 365 -subj /CN=integration.gomessenger.com openssl x509 -fingerprint -sha256 -in integration.gomessenger.com.crt SHA256 Fingerprint=E2:E5:86:09:F0:91:F4:3C:C2:DE:D1:40:9C:DD:AF:A2:0A:88:EE:19:0C:C5:A6:03:C9:9B:17:6E:8F:58:D2:C3

Now that you have the certificate and the private key file we need to upload these into Rancher. We can upload certs by clicking the Add Certificate button in the Certificates Section of the Infrastructure tab in the Rancher UI. You need to specify a meaningful name for your certificate and optionally a description as well. Copy the contents of integration.gomessenger.com.key and *integration.gomessenger.com.crt *into the Private Key and *Certificate * fields respectively (or select Read from File and select the respective files). Once you have completed the form click save and wait a few moments for the certificate to become active.

* *Once the certificate is active we can add the HTTPS endpoint to our environment. In order to do so we have to modify our docker-compose file to include the SSL port configuration. We add a second port (9001) to the ports section to make it accessible outside the load balancer container and we use the io.rancher.loadbalancer.ssl.ports label to specify that ‘9001’ will be the public load balancer port with SSL termination. Furthermore since we are terminating SSL at the load balancer we can route requests to our actual service container using plain HTTP over the original 9000 port. We specify this mapping from 9001 to 9000 using the io.rancher.loadbalancer.target.auth-service label*. *

auth-lb: ports: - '9000' - '9001' labels: io.rancher.loadbalancer.ssl.ports: '9001' io.rancher.loadbalancer.target.auth-service: 9000=9000,9001=9000 tty: true image: rancher/load-balancer-service links: - auth-service:auth-service stdin_open: true mysql-master: environment: ... ...

We also need to update the rancher-compose file to specify the SSL certificate we should use in the load balancer service for SSL termination. Add the default_cert parameter with the name of the certificate we uploaded earlier. After these changes you will need to delete and recreate your stack as there is currently no way to add these properties to a deployed stack.

auth-lb: scale: 1 default_cert: integration.gomessenger.com_selfsigned load_balancer_config: name: auth-lb config mysql-master: scale: 1 auth-service: scale: 1

Now to make sure everything is working, you can use the following curl command. When you try the same command with the https protocol specifier and the 9001 port you should see a failure complaining about the use of an untrusted certificate. You can use the --insecure switch to turn of trusted certificate checking and use https without it.

# Http Request curl -i -silent -X PUT \ -d userid=<TEST_USERNAME> \ -d password=<TEST_PASS> \ http://integration.gomessenger.com:9000/user # Https Request with secure checking # Note Http(s) and 900(1) curl -i -silent -X PUT \ -d userid=<TEST_USERNAME> \ -d password=<TEST_PASS> \ https://integration.gomessenger.com:9001/user curl: (60) SSL certificate problem, verify that the CA cert is OK. Details: error:14090086:SSL routines:SSL3_GET_SERVER_CERTIFICATE:certificate verify failed # Https Request with insecure checking curl -i -silent -X PUT \ --insecure \ -d userid=<TEST_USERNAME> \ -d password=<TEST_PASS> \ https://integration.gomessenger.com:9001/user

Creating Continuous Deployment pipelines with Rancher and Jenkins

Now that we have created our test environment we can finally get back to the original intent of this article and build out a docker continuous deployment pipeline by extending our Jenkins CI pipeline which built the application, packaged it into a container and ran integration tests against it.

Publishing Docker images

We’re going to start by publishing the packaged image to a docker repository. For simplicity we are using a public DockerHub repository, however, for actual development projects you would want to push your docker images to a private repository. Let’s create a new Free Style Project job in Jenkins by clicking the New Item button and name our job push-go-auth-image. Once you do so, you will be taken to the Jenkins job configuration page where you can define the steps required to push your go-auth image up to Dockerhub.

Since this is a continuation of the pipeline we built in our previous article, the job will have similar configuration to go-auth-integration-test job. The first setting you need is to make it *parameterized build *and adding the GO_AUTH_VERSION parameter.

In order to actually push the image we will select the Add build step drop down and then the Execute shell option. In the resulting text box add the commands shown below. In the commands we are going to log in to docker hub and push the image we built earlier. We’re pushing to the usman/go-auth repository, however, you will need to push to your own DockerHub repository.

As covered in the previous article, we’re using git-flow branching model where all feature branches are merged into the ‘develop’ branch. To continuously deploy changes to our integration environment we need a simple mechanism to generate the latest image based off of develop. In our package job we tagged the docker container using the GO_AUTH_VERSION (e.g., docker build -t usman/go-auth:\${GO_AUTH_VERSION} .…). By default the version will be develop, however, later in this article we’ll create new releases for our application and use the CI/CD pipeline to build, package, test and deploy them to our integration environment. Note that with this scheme, we’re always overwriting the image for our develop branch (usman/go-auth:develop) which prevents us from referencing historical builds and do rollbacks. One simple change that you can make to the pipeline is to attach the Jenkins build number to the version itself, e.g., usman/go-auth:develop-14.

Note that you will need to specify your DockerHub username, password and email. You can either use a parameterized build to specify these for each run or use the Jenkins Mask Passwords Plugin to define these securely, once in the main Jenkins configuration and inject them into the build. Make sure to enable ‘Mask passwords (and enable global passwords)’ under *Build Environment *for your job.

echo ${GO_AUTH_VERSION} docker login -u ${DOCKERHUB_USERNAME} -p ${DOCKERHUB_PASSWORD} -e ${DOCKERHUB_EMAIL} docker push usman/go-auth:${GO_AUTH_VERSION}

Now we have to make sure that this job is triggered after our integration test job. To do that we need to update our integration test job to trigger parameterized build with *current build parameters. *This means that after each successful run of the integration test job we will push the tested image up to Dockerhub.

Lastly, we need to trigger the deployment job once the image is successfully pushed to DockerHub. Again, we can do that by adding a post-build action as we did for other jobs.

Deploying to Integration environment

For this we will use the Rancher compose CLI to; stop the running environment, pull latest images from DockerHub, and restart the environment. A brief word of caution, the Updates API is under heavy development and may change. There will certainly be newer features added in the coming weeks and months so check the Documentation to see if there are updated options. Before we create a Jenkins job to achieve continuous deployment let’s first go through the steps manually.

A simple approach would be to stop all services (auth service, load balancer and mysql), pull the latest images and start all services. This however would be less than ideal for long running environments where we only want to update the application. To update our application, we’re first going to stop auth-service. You can do this by using the stop command with Rancher Compose.

# If you not have already done so # git clone https://github.com/usmanismail/go-messenger.git # cd go-messenger/deploy rancher-compose --project-name messenger-int \ --url http://YOUR_RANCHER_SERVER:PORT/v1/ \ --access-key <API_KEY> \ --secret-key <SECRET_KEY> \ --verbose stop auth-service

This will stop all containers running for auth-service which you can verify by opening the stack in the Rancher UI and verifying that the status of the service is set to Inactive. Next, we’ll tell rancher to pull the image version we want to deploy. Note that the version we specify here will be substituted in our docker compose file for the auth service ( image: usman/go-auth:\${auth_version} ).

auth_version=${version} rancher-compose --project-name messenger-int \ --url http://YOUR_RANCHER_SERVER:PORT/v1/ \ --access-key <API_KEY> \ --secret-key <SECRET_KEY> \ --verbose pull auth-service

Now that we have pulled the image we want, all that is needed is to start the application.

auth_version=${version} rancher-compose --project-name messenger-int \ --url http://YOUR_RANCHER_SERVER:PORT/v1/ \ --access-key <API_KEY> \ --secret-key <SECRET_KEY> \ --verbose start

As of Rancher release version 0.44.0, the three steps listed above can be run by a single up command using the --force-upgrade switch as follows:

auth_version=${version} rancher-compose --project-name messenger-int \ --url http://YOUR_RANCHER_SERVER:PORT/v1/ \ --access-key <API_KEY> \ --secret-key <SECRET_KEY> \ --verbose up -d --force-upgrade --pull --confirm-upgrade auth-service

Now the we know how to run our update lets create a Jenkins job in our pipeline to do so. As before create a new freestyle project and name it *deploy-integration. *As with all other jobs, this will also be a parameterized build with GO_AUTH_VERSION as a string parameter. Next we need to copy over artifacts from the upstream build-go-auth job.

Lastly, we need to add the Execute Shell build step with the Rancher compose up command that we specified earlier. Note that you will also need to setup rancher-compose on Jenkins ahead of time and make it available to your build on the system path. We are setting up our job to reinstall compose every time for the sake of simplicity. You will need to specify the Rancher API key, Rancher API Secret and your Rancher server URL as part of the execution script. As before you may use the Parameterized build option or the Masked Passwords plugin to avoid exposing your secret or having to enter it every time. The complete contents of the execute shell step looks like the snippet shown below. Note that unless if you have multiple Rancher compose nodes the load balancer containers may launch on different host and hence your route 53 record-set may need to be updated.

cd deploy wget https://github.com/rancher/rancher-compose/releases/download/v0.5.1/rancher-compose-linux-amd64-v0.5.1.tar.gz -O - | tar -zx mv rancher-compose-v0.5.1/rancher-compose . rm -rf rancher-compose-v0.5.1 ./rancher-compose --project-name messenger-int \ --url http://YOUR_RANCHER_SERVER:PORT/v1/ \ --access-key <API_KEY> \ --secret-key <SECRET_KEY> \ -- verbose up -d --force-upgrade --pull --confirm-upgrade auth-service

With our two new Jenkins jobs the Pipeline we started in the Docker Based Build Pipelines article, now looks like the image shown below. Every check-in to our sample application now gets compiled to make sure there are not syntax errors and that the automated tests pass. That change then gets packaged, and tested with integration testes and finally deployed for manual testing. The five steps below provide a good baseline template for any build pipeline and helps predictably move code from development to testing and deployment stages. Having a continuous deployment pipeline ensures that all code is not only tested by automated systems but is available for human testers quickly. It also serves as a model for production deployment automation and can test the operations tooling and code to deploy your application on a continual basis.

Releasing and deploying a new version

Once we have deployed our code to a persistent testable environment we will let QA (Quality Assurance) team test the changes for a period of time. Once they certify that the code is ready, we can create a release which will subsequently be deployed to production. The way releases work with git-flow is similar to how feature branches (which we talked about in the previous article work. We start a release using the git flow release start [Release Name] command (shown below). This will create a new named release branch. In this branch we will perform house-keeping actions such as incrementing version numbers and making any last minute changes.

git flow release start v1 Switched to a new branch 'release/v1' Summary of actions: - A new branch 'release/v1' was created, based on 'develop' - You are now on branch 'release/v1' Follow-up actions: - Bump the version number now! - Start committing last-minute fixes in preparing your release - When done, run: git flow release finish 'v1'

Once done we can we can run the release finish command to merge the release branch into the master branch. This way master always reflects the latest released code. Further each release is tagged so that we have a historical record of what went into each release. Since we don’t want any other changes to go in, let’s finalize the release.

Switched to branch 'master' Merge made by the 'recursive' strategy. README.md | 1 + 1 file changed, 1 insertion(+) Deleted branch release/v1 (was 7ae8ca4). Summary of actions: - Latest objects have been fetched from 'origin' - Release branch has been merged into 'master' - The release was tagged 'v1' - Release branch has been back-merged into 'develop' - Release branch 'release/v1' has been deleted

The last step here is to push the release to remote repository.

git push origin master git push --tags //pushes the v1 tag to remote repository

If you’re using Github for hosting your git repository, you should now have a new release.

It is also a good idea to push images to DockerHub with a version that matches the release name. To do so, let’s trigger our CD pipeline by running the first job. If you recall, we setup Git Parameter plugin in the previous article to fetch all the tags matching our filter from git. This normally defaults to develop however, when we trigger the pipeline manually we can choose from git tags. For example in the section below, we have two releases for our application. Let’s select one of them and kick off the integration and deployment pipeline.

This will go through the following steps and deploy our application with version 1.1 to our long running integration environment all with a couple of clicks:

Fetch the selected release from git Build the application and run unit tests Create a new image with tag v1.1 (e.g., usman/go-auth:v1.1) Run integration tests Push the image (usman/go-auth:v1.1) to DockerHub Deploy this version to our integration environment

In today’s article we covered creating a continuous deployment pipeline which can put our sample application on an integration environment. We also looked at integrating DNS and HTTPS support in order to create a more secure and usable environment with which clients can integrate. In the next article we will look at running production environments. Deploying to production environments presents it’s own set of challenges as we will be expected to deploy under-load, with little (ideally zero) downtime. Furthermore, Production environments present challenges as they have to scale out to meet load while also scaling back to control cost. Lastly, we take a more comprehensive look at DNS management in order to provide automatic fail over and high availability. In subsequent articles we will look at operations management of docker environments in production as well as different types of work-loads for example state-full connected services. To get the entire series, please download our eBook: Continous Integration and Deployment with Docker and Rancher. You can also join us for this months online Rancher meetup to learn more about building docker-based operations processes.

Usman and Bilal are server and infrastructure engineers, with experience in building large scale distributed services on top of various cloud platforms. You can read more of their work at techtraits.com, or follow them on twitter @usman_ismail and @mbsheikh respectively.