Instrument Blockchain-API with performance metrics

[yourbuddyconner]

Blockchain API:

• RPM (Counter w/ labels for request_verb and endpoint)
• Response time (Histogram)
• Response codes (Counter w/ label for response_code)
• Number of “unknown” transaction types (Gauge (?))

Repo: https://github.com/celo-org/wallet/tree/main/packages/blockchain-api

Recommended course of Action:

• Instrument Blockchain-API using the Node.js Client Library for Prometheus.
  Example here: https://github.com/siimon/prom-client/blob/master/example/server.js

[yourbuddyconner]

Talked with @gnardini about this and we came up with a couple more metrics. We also decided that we'd already identified the most important status metric for this service as being the RPM on a per-endpoint/response-code basis.

• query_exchange_rate_duration - (Histogram) a measure of the execution duration of the queryExchangeRate method
• pipeline_duration - (Histogram) a measure of the execution duration of the entire pipeline which is executed for each request, this might overlap with the RPM metrics.
• get_raw_token_transactions_duration - (Histogram) a measure of the execution duration of the getRawTokenTransactions method which fetches data from blockscout.

[yourbuddyconner]

Some examples of the queries/graphs we can make:

[yourbuddyconner]

PR for this ticket is here: valora-inc/wallet#115

cc @gnardini and @carterqw2 for review.

[carterqw2]

Agree with the metrics, let's do it.

[yourbuddyconner]

PR Closed