Rate Limiting in Ingress Gateway

In this document, we will enable a rate limit in the Ingress Gateway and show how to rate limit based on the HTTP request user-agent string.

Before you get started, make sure you:
✓ Familiarize yourself with TSB concepts
✓ Install the TSB environment. You can use TSB demo for quick install
✓ Completed TSB usage quickstart. This document assumes you already created Tenant and are familiar with Workspace and Config Groups. Also you need to configure tctl to your TSB environment.

Enable Rate Limiting Server

Read and follow the instructions on Enabling the Rate Limiting Server document.

Demo Installation

If you are using the TSB demo installation, you already have rate limit service running and ready to use, and can skip this section.

Deploy httpbin Service

Follow the instructions in this document to create the httpbin service. You can skip the sections "Create Certificates" and "Onboard httpbin Application".

Rate limit based on User-agent

Create a file called rate-limiting-ingress-config.yaml which edits the existing Ingress Gateway to also rate limit every value for User-agent header at 5 requests/minute. Replace the organization and tenant with appropriate values

Details for other rate limiting options can be found in this document

apiVersion: gateway.tsb.tetrate.io/v2
kind: IngressGateway
metadata:
  name: httpbin-gateway # Need not be the same as spec.labels.app
  organization: <organization>
  tenant: <tenant>
  group: httpbin-gateway
  workspace: httpbin
spec:
  workloadSelector:
    namespace: httpbin
    labels:
      app: httpbin-ingress-gateway # name of Ingress Gateway created for httpbin
  http:
    - name: httpbin
      hostname: "httpbin.tetrate.com"
      port: 80
      routing:
        rules:
          - route:
              host: "httpbin/httpbin.httpbin.svc.cluster.local"
              port: 8000
      rateLimiting:
        settings:
          rules:
          - dimensions:
            - header:
                name: user-agent
            limit:
              requestsPerUnit: 5
              unit: MINUTE

Configure the Ingress Gateway with tctl:

tctl apply -f rate-limiting-ingress-config.yaml

Testing

You can test the rate limiting by sending HTTP requests from an external machine or your local environment to the httpbin Ingress Gateway, and observe the rate limiting take effect after a certain number of requests.

In the following example, since you do not control httpbin.tetrate.com, you will have to trick curl into thinking that httpbin.tetrate.com resolves to the IP address of the Tier-1 Gateway.

Obtain the IP address of the Tier-1 Gateway that you previously created using the following command.

kubectl -n httpbin get service httpbin-ingress-gateway -o jsonpath='{.status.loadBalancer.ingress[0].ip}'

Then execute the following command to send HTTP requests to the httpbin service through the Ingress Gateway. Replace the gateway-ip with the value you obtained in the previous step.

curl -k -v "http://httpbin.tetrate.com/get" \
    --resolve "httpbin.tetrate.com:80:<gateway-ip>" \
    -s \
    -o /dev/null \
    -w "%{http_code}\n" \
    -H "X-B3-Sampled: 1"

For the first 5 requests you should see "200" on your screen. After that, you should start seeing "429" instead.

You can change the user-agent header to another unique value to get a successful response.

curl -k -v -A "another-agent" \
    "http://httpbin.tetrate.com/get" \
    --resolve "httpbin.tetrate.com:80:<gateway-ip>" \
    -s \
    -o /dev/null \
    -w "%{http_code}\n" \
    -H "X-B3-Sampled: 1"

After 5 requests, you should start seeing "429" again, until you change the header again.