maria-geir

README

maria-geir

Sample repo showing Envoy used for several services plus a portal that documents them

What's in here anyway?

The following have been setup and are run with docker compose

• grpc server written in java running greeter service: normal and pirate mode available
• grpc client written in golang that calls the remote service (and accepts an optional key as an argument)
• a graphql service. This uses all flat files and is simply the book list example. It's self contained
• kafka and zookeepr for said kafka
• a nodejs service that constantly sends messages to a kafka topic called messages
• a nodejs service that consumes that topic and then sends those messages to any websocket clients that connect and use a unique groupId
• an envoy service that proxies for all of it.

And a nice image:

What's coming

I'm in the process of building out a few more things

• documentation published in the portal for all provided services

The idea here is to create working example where apigee is used in concert with a simple microservice to translate kafka -> websockets, proxy for gRPC, and proxy for graphql.

Getting setup

Run the following:

NB:

• The email will be used to create the developer and so needs to be a user with rights. Probably your own email (no password is used)
• The remote url is probably the base url of your Apigee X setup. If you've used the auto-provisioner it will be one that ends in nip.io
• You'll need to create a service-account and store the key locally and then refer to that key as outlined below

Run the setup like so:

./setup.sh -a <path-to-ax-sa-json> -o your-org -e your-environment -t $(gcloud beta auth print-access-token) -r "http://remote-url-for-apigee-x" -u user@email.com

With that complete you'll need to add the following api_header setting your to your config.yaml file. Simply locate the auth stanza and add append api_header: x-target-name like so:

    auth:
      jwt_provider_key: https://1.2.3.4.nip.io/remote-token/token
      append_metadata_headers: true
      api_header: x-target-name

Building and Runnig it once configured

To get this running you'll need to build it all (after you've run setup mind you) by doing:

docker-compose build

Once it's built you can play with any of the config files and environment variables named in docker-compose.yaml

Finally you can run it by:

docker-compose up

Testing it all

Here I've provide a number of commands I've used to test all of this. One thing I've used is a websocket cli called wscat. So my examples use it.

Every example I provide here refers to <apikey>. You'll need to replace that with the key stored in my_app.json which is created when the setup script finishes.

Testing the websocket bit:

The point of the websocket is two fold:

1. Show how we might use envoy with the envoy adapter to act as a proxy for websockets
2. Use the websocket server as a mediation point: websocket <-> kafka

The websocket server is itself subscribing to a kafka topic that's being populated by another nodejs-service: a producer. Provide a groupId as shown below or it will default to one ... And that one will only work once of course.

 wscat -c http://localhost:8080/ws -H x-api-key:<apikey> -H "x-group-id: first"

Testing the graphql bit:

The graphql server is simple. A nodejs service returning a hardcoded list based on a schema for books. You can make a query like so with curl:

curl -i 'http://localhost:8080/graphql' -H 'Accept-Encoding: gzip, deflate, br' -H 'Content-Type: application/json' -H 'Accept: application/json' -H 'Connection: keep-alive' --data-binary '{"query":"{\n  books {\n    title\n    author\n  }\n}"}' -H "x-api-key: <apikey>" -H "host: envoy.local"

Testing the gRPC bit:

We talk a whole lot about proxying for gRPC but what does it look like. This example uses vanilla envoy with the envoy adapter to proxy a java-springboot gRPC service. I've provided a simple golang-grpc client that you can use to test this service.

Execute that test like so:

cd go-grpc-client/
GOPATH=$GOPATH:$(pwd) go run main.go -h localhost -p 8080 -k <apikey> gobblybook

Or if you'd like a pirate response add the -pirate flag like so

cd go-grpc-client/
GOPATH=$GOPATH:$(pwd) go run main.go -h localhost -p 8080 -pirate -k <apikey> gobblybook