How to auth to Grafana Cloud Prometheus using an Access Policy Token with promtool

promtool-grafana-cloud-access-policy-token-auth.md

The docs are here but don't specify this level of detail, I found this through trial/error: https://prometheus.io/docs/prometheus/latest/configuration/configuration/#http_config

Also see, prometheus/prometheus#12924.

1. Set your access policy up and create a token for it at https://grafana.com/orgs/{{ORG_NAME}}/access-policies
2. Get your QUERY_ENDPOINT + INSTANCE_ID from https://grafana.com/orgs/{{ORG_NAME}}/members, then click your stack on the left, https://grafana.com/orgs/hedera/stacks/{{STACK_ID}}, then click Prometheus and scroll down to get your Instance ID (https://grafana.com/orgs/hedera/hosted-metrics/{{USERNAME/INSTANCE_ID}}
3. Then create a file with the creds, e.g. .promtool-http-config.yml with the below format:

   authorization:
     type: Bearer
     credentials: {{INSTANCE_ID}}:{{TOKEN}}

4. Then run your query promtool query instant --http.config.file=.prom-http-config.yml {{QUERY_ENDPOINT}} {{QUERY}} e.g.

   promtool query instant --http.config.file=.promtool-http-config.yml prometheus-blocks-prod-us-central1.grafana.net/api/prom {{QUERY}}