datasources.yml

# documentation for this is sometimes a bit lacking but you can see clues from https://github.com/grafana/grafana/blob/main/devenv/datasources.yaml

apiVersion: 1

datasources:

- name: Prometheus
  type: prometheus
  uid: prometheus
  access: proxy
  orgId: 1
  url: http://prometheus:9090
  basicAuth: false
  isDefault: false
  version: 1
  editable: false
  jsonData:
    httpMethod: GET
    # manageAlerts: true
    # alertmanagerUid: gdev-alertmanager
    # prometheusType: Prometheus #Cortex | Mimir | Prometheus | Thanos
    # prometheusVersion: 2.40.0
    exemplarTraceIdDestinations:
    - name: traceID
      datasourceUid: tempo

- name: Tempo
  type: tempo
  uid: tempo
  access: proxy
  orgId: 1
  url: http://tempo:3200
  basicAuth: false
  isDefault: true
  version: 1
  editable: true
  apiVersion: 1
  jsonData:
    httpMethod: GET
    serviceMap: # This enables the "service graph" tab on the tempo explore page
      datasourceUid: 'prometheus'
    lokiSearch: # This enables the "loki search" tab on the tempo explore page
      datasourceUid: 'loki'
    nodeGraph: # This enables the "node graph" panel when viewing a trace
      enabled: true
    search:
      hide: false

    tracesToLogsV2:
      datasourceUid: loki
      spanStartTimeShift: '-10m'
      spanEndTimeShift: '10m'
      filterByTraceID: false
      filterBySpanID: false
      customQuery: true
      tags:
        - { key: 'service.name', value: 'service_name' }
      query: '{app="boomer"} | logfmt |= "$${__span.traceId}"'

      # both of these result in grafana failing to link to the logs
      #
      # query: '{app="boomer"} | logfmt | service_name="$${__span.tags.service_name}" |= "$${__span.traceId}"'
      # query: '{app="boomer"} | logfmt | service_name="$${service_name}" | trace_id="$${__span.traceId}"'

    tracesToMetrics:
      datasourceUid: 'prometheus'
      spanStartTimeShift: '-1h'
      spanEndTimeShift: '1h'
      tags: # used for the queries below
        # tag keys here are the span/resource attributes
        # tag values (if specified) are the prometheus label names .. if not specified this defaults to the tag key
        - { key: 'service.name', value: 'service' }
      queries:
        # 2023-12-22 : queries only support "$__tags" interpolation: https://github.com/grafana/grafana/blob/feb7b38fba1f8d694395efa803c742d2678eab7e/public/app/features/explore/TraceView/createSpanLink.tsx#L589
        # - This is pretty limiting as you can't use the span name
        # - You can quite easily set a breakpoint on that function in your browser
        - name: 'count/2min'
          query: 'increase(traces_spanmetrics_calls_total{$$__tags}[2m])'

- name: Loki
  type: loki
  uid: loki
  access: proxy
  orgId: 1
  url: http://loki:3100
  version: 1
  editable: false
  isDefault: false

  correlations: # https://grafana.com/docs/grafana/latest/administration/correlations/
    - targetUID: prometheus
      label: "Logs to metrics"
      description: "Related metrics stored in Prometheus"
      config:
        type: query
        target:
          expr: >
            { job="boomer" }
        field: "TraceID" # matches the derived field name in the datasource below

  jsonData:
    maxLines: 1000
    derivedFields: # Field with internal link pointing to data source in Grafana.
      - datasourceUid: tempo
        matcherRegex: "trace_id=(\\w+)"
        name: TraceID
        url: '$${__value.raw}'        # url will be interpreted as query for the datasource
        urlDisplayLabel: 'View Trace' # optional for URL Label to set a custom display label for the link