Linkerd traffic splitting 🧙🏼

This demonstrates Linkerd's traffic splitting with real code.

• This code deploys 3 Apps with 1 client
• go-open-api-v2 will start rejecting the client creation calls as it has a change in it's spec.

This example deploys three backends that all operate slightly differently. We can deploy traffic split to measure their performance...

As seen here...

And now we see our split traffic ✨

Setup 🙋

• kind create cluster --image rossgeorgiev/kind-node-arm64:v1.20.0
• linkerd install | kubectl apply -f -
• linkerd viz install | kubectl apply -f -
• kubectl create ns apps
• kubectl annotate ns apps "linkerd.io/inject=enabled"

cd demo
./deploy_with_helm.sh

❯ k get pods -n apps
NAME                                 READY   STATUS    RESTARTS   AGE
go-openapi-client-668b94dbf4-wp46d   2/2     Running   0          2m24s
go-openapi-v1-549c9cb676-kj7z7       2/2     Running   0          2m34s
go-openapi-v2-7bb874cf5b-qbtpf       2/2     Running   0          2m30s
go-openapi-v3-7d4dfcd8d4-fq7vd       2/2     Running   0          115s

Apply the traffic split kubectl apply -f demo/traffic-split.yaml 💅

Code differences with go-openapi-v2

The V2 API decided all users need to state their food preferences for the international buffet. 🥝🫑🌶🥒🥬

#go-openapi-v2
definitions:
  User:
    type: "object"
    required:
      - foodPreference
    properties:
      id:
        type: "integer"
        format: "int64"
      username:
        type: "string"
      firstName:
        type: "string"
      lastName:
        type: "string"
      foodPreference:
        type: "string"

Let's post to test that new API directly...

curl -X POST "http://localhost:8080/v2/user" -H  "accept: application/xml" -H  "Content-Type: application/json" -d "{  \"email\": \"string\",  \"firstName\": \"string\",  \"id\": 0,  \"lastName\": \"string\",  \"password\": \"string\",  \"phone\": \"string\",  \"userStatus\": 0,  \"username\": \"alex\"}"
{"code":602,"message":"foodPreference in body is required"}%

Bummer! 🙅🏽

See that a bunch of stuff is erroring out due to missing field on the User object yay, it works! 👍

│ go-openapi-client &{[email protected] Matthew Harris <nil> 0 Wilson Cougarfir +243 56 11472 4389 0 Spiritshell}                                                           │
│ go-openapi-client Error:  [POST /user][422] createUser default                                                                                                                      │
│ go-openapi-client &{[email protected] Addison Robinson <nil> 0 Thomas Painterrust +371 750 5343 155 2 0 Fishersleet}                                                    │
│ go-openapi-client Error:  [POST /user][422] createUser default                                                                                                                      │
│ go-openapi-client &{[email protected] Olivia White <nil> 0 Thompson Whipwheat +241 665 6 0395302 0 Thiefdark}                                                              │
│ go-openapi-client &{[email protected] Madison Miller <nil> 0 Davis Touchplanet +972 037 3996359 5 0 Tradergravel}                                                        │
│ go-openapi-client Error:  [POST /user][422] createUser default                                                                                                                      │
│ go-openapi-client &{[email protected] William Williams <nil> 0 Garcia Binderplume +880 304 77801444 0 Foxrowan}                                                          │
│ go-openapi-client Error:  [POST /user][422] createUser default                                                                                                                      │
│ go-openapi-client &{[email protected] Olivia Wilson <nil> 0 Williams Salmonoasis +252 4 1543558433 0 Ladysplit}                                                        │
│ go-openapi-client Error:  [POST /user][422] createUser default                                                                                                                      │
│ go-openapi-client &{[email protected] Matthew Miller <nil> 0 White Volescratch +506 201 753 611 52 0 Whipchrome}                                                          │
│ go-openapi-client Error:  [POST /user][422] createUser default                                                                                                                      │
│ go-openapi-client &{[email protected] James Anderson <nil> 0 Taylor Butterflysugar +45 33 817 26608 55 0 Cowlbrick}                                                         │
│ go-openapi-client &{[email protected] Avery White <nil> 0 Thomas Napeshadow +33 73 9182632411 0 Servantharvest}                                                              │
│ go-openapi-client &{[email protected] Natalie Jones <nil> 0 Robinson Pixieglory +993 85 23550 92 3 2 0 Vulturetulip}                                                        │
│ go-openapi-client &{[email protected] Benjamin Thompson <nil> 0 White Slicerweak +963 717 1 6 124055 0 Shirttranslucent}                                                    │
│ go-openapi-client &{[email protected] Mia Williams <nil> 0 Miller Whaleolive +218 53 81547153 6 0 Princessbog}

Code differences with go-openapi-v3

This backend introduces heavy latency