[Dx-1292] Add Python gRPC Deployment To tyk-demo

[dcs3spp]

This PR adds a Python gRPC Server to tyk-demo. The deployment is named python-grpc-server and contains the following files:

• README: Documents usage and config.
• Dockerfile: Builds the tyk-python-grpc-server image when run ./up.sh tyk-python-grpc-server for the first time. Configurable via a build arg (GATEWAY_VERSION)
• docker-compose.yml: Contains a tyk-python-grpc-server docker compose service with custom docker build, has GATEWAY_VERSION build arg set from tyk-demo GATEWAY_VERSION env var or a provided default of 5.3.0.
• bootstrap.sh: names the deployment, sets up API (python-grpc-custom-auth), creates HMAC enabled key and logs bootstrap of deployment.
• pyproject.toml and poetry.lock files: Python dependencies used for building Docker image.
• tyk_async_server.py: gRPC server source code that implements the Tyk Dispatcher service. Displays in JSON format, the object parameter that Tyk Gateway sends per plugin request. Implements custom authentication plugin for HMAC.
• scripts/hmac.sh: Script that users can use for testing API configured with custom auth plugin at gRPC server

Is it possible to configure coprocess gRPC server for only this deployment or would it have to be enabled in tyk.conf of the Gateway? Currently, in tyk.conf of GW deployment, coprocess is enabled.

[dcs3spp]

Hi @dcs3spp. I'm starting to review the PR.

I got a 401 from this request:

curl --location 'http://tyk-gateway.localhost:8080/grpc-custom-auth/get' \
--header 'Authorization: eyJvcmciOiI1ZTlkOTU0NGExZGNkNjAwMDFkMGVkMjAiLCJpZCI6ImdycGNfaG1hY19rZXkiLCJoIjoibXVybXVyNjQifQ=='

I found that by changing the api_id in the key from 662facb2f03e750001a03500 to 6c56dd4d3ad942a94474df6097df67ed the request would work. Does the key work for you?

Thanks for the review @davegarvey, the API implements a gRPC custom auth plugin that requires a Authorization header formatted for HMAC signature. There is a bash script, scripts/hamc.sh, of the deployment folder to run a curl command:

curl -v -H "Date: ${date}" \
    -H "Authorization: Signature keyId=\"${KEY}\",algorithm=\"${HMAC_ALGORITHM}\",signature=\"${url_encoded_signature}\"" \
    ${REQUEST_URL}

Does running the above script work in your environment?

I am not sure why my plugin authorises the request with the key change though. I will update my environment and try it out and see if it does the same and then get back to you here

---

I have pulled latest changes from the branch and rebuilt the docker image and updated the hmac script so it requests to endpoint /grpc-custom-auth/get instead of /grpc-custom-auth.

I have tried running the hmac script and the curl and attached a screenshot image:

In my environment I get a 400 when running:

curl --location 'http://tyk-gateway.localhost:8080/grpc-custom-auth/get' \
--header 'Authorization: eyJvcmciOiI1ZTlkOTU0NGExZGNkNjAwMDFkMGVkMjAiLCJpZCI6ImdycGNfaG1hY19rZXkiLCJoIjoibXVybXVyNjQifQ=='

I've improved the deployment readme file to include an example request