adservice2

adservice2

This is a rewrite of the adservice application in Go and using a REST protocol instead of the original JAVA based app using GRPC.

This was added to demonstrate more use-cases then only internal GRPC calls.

Usage

Usage of ./adservice2:
  -EXTRA_LATENCY=0s: lattency to add to service response
  -startDelay=0s: delay before service is available (return 503 failed probe)
  -bindDelay=0s: delay before binding the service port at startup
  -consecutiveError=0: number of error 500 to return before answering the call
  -JAEGER_SERVICE_ADDR="": URL to Jaeger Tracing agent
  -ZIPKIN_SERVICE_ADDR="": URL to Zipkin Tracing agent (ex: zipkin:9411)
  -adFile="ads.json": path to the Ads json file
  -logLevel="warn": log level from debug, info, warning, error. When debug, genetate 100% Tracing
  -srvURL=":9555": IP and port to bind, localhost:9555 or :9555
  -version=false: Show version and quit

All command line options can be set using env variables by using the same argument in LOWERCASE.

A default ads.json file is provided and describes all the possible ads:

  {
    "text": "Film camera for sale. 50% off.", 
    "redirect_url": "/product/2ZYFJ3GM2N", 
    "tags": ["photography","vintage"]
  },

The redirect URL is supposed to be a link to an existing product of the Hipstershop Tags are keywords used to greate pools of adds. When starting, the adservice2 will load the list of Ads and index them by tags.

API

/ad

curl http://localhost:9555/ad should return a JSON payload with an array containing a random Ad.

/ads/

curl http://localhost:9555/ads/vintage should return a JSON payload with an array containing all the ads from a category (having the same tag)

It's the clients role to filter/order the ad it needs.

Errors

when --consecutiveError=N is set (ex: --consecutiveError=3), calls to /ad or /ads/xxx will be answered with an error 503 N times before the real answer is returned. If --consecutiveError=1, 50% of the requests will be error 503

This is used to demo the Istio retry and circuit-breaker behaviours.

Delays

Use --bindDelay=10s to delay the start of the server by 10s. During this time the process is running but no network port is opened, so connections attempts will return a can't connect error.

Use --startDelay=10sto delay the liveness by 10s. During this time every Healthz request will get an HTTP error 503. You can test this by using curl: curl http://localhost:9555/healthz

The startDelay time is ADDED to the bindDelay