scenario-6

Scenario 6 - Apply rate-limiting to managed API in Kubernetes cluster

• This scenario describes how to apply rate-limiting to a managed API in Kubernetes cluster
• First, we will deploy a rate-limiting custom resource which contains the policy ( 5 requests per minute)
• Then the created rate-limiting policy/CR will be referred in the swagger definition of the API
• Petstore service will be exposed as a managed API with ratelimiting in the Kubernetes cluster
• Finally, we will invoke the API continuously and observe the throttling behavior.

Important:

Follow the main README and deploy the api-operator and configuration files. Make sure to set the analyticsEnabled to "true" and deploy analytics secret with credentials to analytics server and certificate, if you want to check analytics.

Deploying the artifacts

• Navigate to scenarios/scenario-6 directory.

• Deploy the sample rate-limiting CR using the following command.

  >> apictl apply -f five-req-policy.yaml
  
  Output:
  ratelimiting.wso2.com/fivereqpolicy created
  

• Prepared petstore basic swagger definition can be found within this directory.

• Rate limiting policies to be applied on the API, should be mentioned in the swagger file with the "x-wso2-throttling-tier" extension. In this swagger definition, the rate limiting policy has been mentioned as follows.

  x-wso2-throttling-tier: fivereqpolicy
  

• Execute the following to expose pet-store as an API.

• Create API
  

  >> apictl add api -n petstore-rate --from-file=swagger.yaml --override
  
  Output:
  creating configmap with swagger definition
  configmap/petstore-rate-swagger created
  api.wso2.com/petstore-rate created
  

  Note: --override flag is used to you want to rebuild the API image even if it exists in the configured docker repository.

• Get available API
  

  >> apictl get apis
  
  Output:
  NAME          AGE
  petstore-rate   5m
  

• Get service details to invoke the API. (Please wait until the external-IP is populated in the corresponding service)

  >> apictl get services
  
  Output:
  NAME            TYPE           CLUSTER-IP   EXTERNAL-IP       PORT(S)                         AGE
  petstore-rate   LoadBalancer   10.83.4.44   104.197.114.248   9095:30680/TCP,9090:30540/TCP   8m20s
  

  • You can see petstore service has been exposed as a managed API.
  • Get the external IP of the managed API's service

• Invoking the API
  

  TOKEN=eyJ4NXQiOiJNell4TW1Ga09HWXdNV0kwWldObU5EY3hOR1l3WW1NNFpUQTNNV0kyTkRBelpHUXpOR00wWkdSbE5qSmtPREZrWkRSaU9URmtNV0ZoTXpVMlpHVmxOZyIsImtpZCI6Ik16WXhNbUZrT0dZd01XSTBaV05tTkRjeE5HWXdZbU00WlRBM01XSTJOREF6WkdRek5HTTBaR1JsTmpKa09ERmtaRFJpT1RGa01XRmhNelUyWkdWbE5nX1JTMjU2IiwiYWxnIjoiUlMyNTYifQ.eyJzdWIiOiJhZG1pbkBjYXJib24uc3VwZXIiLCJhdWQiOiJKRmZuY0djbzRodGNYX0xkOEdIVzBBR1V1ME1hIiwibmJmIjoxNTk3MjExOTUzLCJhenAiOiJKRmZuY0djbzRodGNYX0xkOEdIVzBBR1V1ME1hIiwic2NvcGUiOiJhbV9hcHBsaWNhdGlvbl9zY29wZSBkZWZhdWx0IiwiaXNzIjoiaHR0cHM6XC9cL3dzbzJhcGltOjMyMDAxXC9vYXV0aDJcL3Rva2VuIiwiZXhwIjoxOTMwNTQ1Mjg2LCJpYXQiOjE1OTcyMTE5NTMsImp0aSI6IjMwNmI5NzAwLWYxZjctNDFkOC1hMTg2LTIwOGIxNmY4NjZiNiJ9.UIx-l_ocQmkmmP6y9hZiwd1Je4M3TH9B8cIFFNuWGHkajLTRdV3Rjrw9J_DqKcQhQUPZ4DukME41WgjDe5L6veo6Bj4dolJkrf2Xx_jHXUO_R4dRX-K39rtk5xgdz2kmAG118-A-tcjLk7uVOtaDKPWnX7VPVu1MUlk-Ssd-RomSwEdm_yKZ8z0Yc2VuhZa0efU0otMsNrk5L0qg8XFwkXXcLnImzc0nRXimmzf0ybAuf1GLJZyou3UUTHdTNVAIKZEFGMxw3elBkGcyRswzBRxm1BrIaU9Z8wzeEv4QZKrC5NpOpoNJPWx9IgmKdK2b3kIWJEFreT3qyoGSBrM49Q
  

  >> curl -X GET "https://<external IP of LB service>:9095/petstorerate/v1/pet/55" -H "accept: application/xml" -H "Authorization:Bearer $TOKEN" -k
  

  • Once you execute the above command, it will call to the managed API (petstore-rate), which then call its endpoint(https://petstore.swagger.io/v2). If the request is success, you would be able to see the response as below.

    <?xml version="1.0" encoding="UTF-8" standalone="yes"?><Pet><category><id>55</id><name>string</name></category><id>55</id><name>SRC_TIME_SIZE</name><photoUrls><photoUrl>string</photoUrl></photoUrls><status>available</status><tags><tag><id>55</id><name>string</name></tag></tags></Pet>
    

  • Continue to call the API with above curl for more than 5 times. After 5th time, you will get the following error message saying that the request has been throttled out.

    {"fault":{"code":900802, "message":"Message throttled out", "description":"You have exceeded your quota"}}
    

• Delete the API
  

  • Following command will delete all the artifacts created with this API including pods, deployment and services.

    apictl delete api petstore-rate
    apictl delete ratelimitings fivereqpolicy
    
    Output:
    api.wso2.com "petstore-rate" deleted
    ratelimiting.wso2.com "fivereqpolicy" deleted