[usage] Implement BillingService

[easyCZ]

Description

Implements UpdateInvoices RPC on BillingService.

There are 2 implementations:

1. NoOp implementation for Self-hosted
2. Stripe implementation which re-uses the existing stripe.Client

With this PR, the flow changes to the following:

1. Usage Controller is triggered with a cron
2. Usage is retrieved and stored in the DB
3. Instead of then triggering the old BillingController, the BillingService.UpdateInvoices(sessions) is invoked over a grpc self-connection

Behaviour of the component remains unchanged. Tests are updated to move to the corresponding parts.

The benefit of using na RPC is that we get metrics for the RPCs but also we incrementally decouple the UsageController from the Billing one. In subsequent PRs, a similar RPC will be introduced for collecting Usage and these two RPCs will then be chained. We started with Billing as it's easier to do initially and reduces the size of subsequent PRs. If you want to see how this looks, here's a PoC which converts both.

Related Issue(s)

Relates to #10785

How to test

Unit tests
Preview

Release Notes

NONE

Documentation

Werft options:

• /werft with-preview with-billing

[easyCZ]

/werft run with-preview with-billing

👍 started the job as gitpod-build-mp-usage-billing-service-impl.7
(with .werft/ from main)

[werft-gitpod-dev-com]

started the job as gitpod-build-mp-usage-billing-service-impl.8 because the annotations in the pull request description changed
(with .werft/ from main)

[easyCZ]

/werft run with-preview with-billing

👍 started the job as gitpod-build-mp-usage-billing-service-impl.13
(with .werft/ from main)

[andrew-farries]

/hold for one extra test

[easyCZ]

/hold
For me to validate one part of this change.

[easyCZ]

/unhold

[andrew-farries]

FYI, this looks like it's failing to establish the gRPC connection to itself in staging:

{"config":{"controllerSchedule":"1h","creditsPerMinuteByWorkspaceClass":{"default":0.1666666667,"gitpodio-internal-xl":0.3333333333},"stripeCredentialsFile":"stripe-secret/apikeys","contentServiceAddress":"content-service:8080","server":{"services":{"grpc":{"address":":9001"}}}},"level":"info","message":"Starting usage component.","serviceContext":{"service":"usage","version":"commit-c4708b30483eae2bcd07144178252291ea97c326"},"severity":"INFO","time":"2022-07-27T09:32:20Z"}
{"level":"info","message":"Starting usage controller.","serviceContext":{"service":"usage","version":"commit-c4708b30483eae2bcd07144178252291ea97c326"},"severity":"INFO","time":"2022-07-27T09:32:20Z"}
{"component":"grpc","level":"warning","message":"2022/07/27 09:32:20 WARNING: [core] [Channel #2 SubChannel #3] grpc: addrConn.createTransport failed to connect to {","serviceContext":{"service":"usage","version":"commit-c4708b30483eae2bcd07144178252291ea97c326"},"severity":"WARNING","time":"2022-07-27T09:32:20Z"}
{"component":"grpc","level":"warning","message":"  \"Addr\": \":9001\",","serviceContext":{"service":"usage","version":"commit-c4708b30483eae2bcd07144178252291ea97c326"},"severity":"WARNING","time":"2022-07-27T09:32:20Z"}
{"component":"grpc","level":"warning","message":"  \"ServerName\": \"localhost:9001\",","serviceContext":{"service":"usage","version":"commit-c4708b30483eae2bcd07144178252291ea97c326"},"severity":"WARNING","time":"2022-07-27T09:32:20Z"}
{"component":"grpc","level":"warning","message":"  \"Attributes\": null,","serviceContext":{"service":"usage","version":"commit-c4708b30483eae2bcd07144178252291ea97c326"},"severity":"WARNING","time":"2022-07-27T09:32:20Z"}
{"component":"grpc","level":"warning","message":"  \"BalancerAttributes\": null,","serviceContext":{"service":"usage","version":"commit-c4708b30483eae2bcd07144178252291ea97c326"},"severity":"WARNING","time":"2022-07-27T09:32:20Z"}
{"component":"grpc","level":"warning","message":"  \"Type\": 0,","serviceContext":{"service":"usage","version":"commit-c4708b30483eae2bcd07144178252291ea97c326"},"severity":"WARNING","time":"2022-07-27T09:32:20Z"}
{"component":"grpc","level":"warning","message":"  \"Metadata\": null","serviceContext":{"service":"usage","version":"commit-c4708b30483eae2bcd07144178252291ea97c326"},"severity":"WARNING","time":"2022-07-27T09:32:20Z"}
{"component":"grpc","level":"warning","message":"}. Err: connection error: desc = \"transport: Error while dialing dial tcp :9001: connect: connection refused\"","serviceContext":{"service":"usage","version":"commit-c4708b30483eae2bcd07144178252291ea97c326"},"severity":"WARNING","time":"2022-07-27T09:32:20Z"}

[andrew-farries]

although, after restarting the pod it seems fine 🤷

[easyCZ]

Will take a closer look. It's possible it's a race condition between the server starting and the connection.

[andrew-farries]

I made #11743 to track the race at startup.