Step 5 - Update the API to v2.0

In the previous lab, we published version 1.0 of the API. As you noticed, the API Sentence application was not fully developed. The Colors micro-service was not yet available.

The API Dev team has finally finished the Colors micro-service app, and they want to push the app to the Kubernetes environment. They expect the DevOps team to publish this new version of the API Sentence app.

The API Dev team provided us a new version of the OAS spec file. This new version is available here: https://app.swaggerhub.com/apis/F5EMEASSA/API-Sentence/2.0

Note

You can notice a new PATH for Colors

Steps to publish version 2.0 of the API

Deploy the new Colors micro-service in k8s

Let’s deploy the Colors micro-service!

1. SSH (or WebSSH) to the Docker (k3s + Rancher + ELK) VM

2. Run the following kubectl command in order to deploy the Colors micro-service and its k8s service:

   sudo su
   kubectl apply -f /home/ubuntu/k3s/attribut_add_colors.yaml -n api
   

   Note

   As you can notice, this micro-service is deployed in the same NameSpace as the other Words micro-services (api)

3. RDP to the Win10 VM (user/user).

4. Check in Rancher (admin/admin) that the new Deployment has been successful (both the Deployment and Service)

   • Click on the Cluster Explorer yellow button on the top right corner.
   • On the left menu, select Deployments. From here, you can see the Deployments running in each NameSpace
   

5. Open the Edge Browser, select the Random Name Generator bookmark, and check that the new micro-service is providing a color.

   

Warning

Why is the Frontend publishing the Colors micro-service whereas the API Gateway is not yet configured with this new endpoint?

The reason is that the Frontend is directly connected to all k8s micro-services. This is an Front to Back communication. Our NGINX API Gateway is publishing the API externally for other consumers (mobile app, partners…).

Update the API Definition to version 2.0

1. Connect to NGINX Controller, select your existing API Definition api-sentence, and click Edit Version:

   

2. Select OpenAPI Specification -> Copy and paste specification text.

3. Copy and paste the v2.0 OAS YAML content from https://app.swaggerhub.com/apis/F5EMEASSA/API-Sentence/2.0

   

   Note

   Note that the version of the API Definition did not change in the UI (it still shows as v1.0). This is a known bug, and will be fixed in the next release.

4. Click Submit

   Note

   You should now see two more resources -> Resources: 10

   

Update the Published API with the new Colors endpoint

1. The Colors API endpoint is now known by our API Definition, let’s publish it!

2. Select your existing API Definition api-sentence-v1, and click the edit button:

   

3. In the Routing menu, you should now see the API Paths for the Colors endpoint.

4. Click Add New to create a new component for the Colors micro-service.

   1. Name: cp-colors
   2. Click Next
   3. In Workload Groups:
      • Name: wl-colors

      • In Backend Workload URIs:

        • URI: http://10.1.20.8:31102
        • Click Done

      • Click Done
   4. Click Next
   
   1. Click Submit

5. Drag and drop the two new unrouted Path resources for Colors into the cp-colors component

6. Click Submit

Test the v2.0 API deployment

Steps:

1. RDP to the Win10 VM (user/user).

2. Open Postman and select the API Sentence Generator v1 and v2 collection.

3. Send a request with the GET Colors call. The API Gateway will route the request to the Colors micro-service, and will return all the entries (all the words):

   [
       {
           "id": 1,
           "name": "red"
       },
       {
           "id": 2,
           "name": "blue"
       },
       {
           "id": 3,
           "name": "green"
       },
       {
           "name": "black",
           "id": 4
       },
       {
           "name": "yellow",
           "id": 5
       }
   ]
   

4. Send a request with the GET a Sentence from Generator call. This request will ask the generator to get one word per micro-service. As you can see, there is now a new entry for Colors:

   {
      "adjectives": "calm",
      "animals": "whale",
      "colors": "yellow",
      "locations": "park"
   }
   

   Note

   The above entries will generate the sentence calm whale of the yellow park in the Frontend application.

Warning

Congrats! You updated the published API to v2.0 with NGINX Controller and NGINX Plus as an API Gateway! As v2.0 does not break v1.0, we haven’t created a dedicated v2.0 published API. We simply updated v1.0.

In the next lab, we will update the API to v3.0, and this upgrade will break v2.0 as we will create a new parameter for an existing endpoint.