charmcraft.yaml

# Copyright 2021 Canonical Ltd.
# See LICENSE file for licensing details.

name: grafana-agent
type: charm
subordinate: true

description: A subordinate charm for Grafana Agent and an essential part of the COS Lite bundle.
summary: |
  This Charmed Operator handles deployment, scaling, configuration, and Day 2 operations specific to Grafana Agent.

links:
  documentation: https://discourse.charmhub.io/t/grafana-agent-docs-index/13452
  website: https://charmhub.io/grafana-agent
  source: https://github.com/canonical/grafana-agent-operator
  issues: https://github.com/canonical/grafana-agent-operator/issues

bases:
  - build-on:
    - name: "ubuntu"
      channel: "22.04"
      architectures: ["arm64"]
    run-on:
    - name: "ubuntu"
      channel: "22.04"
      architectures: ["arm64"]
  - build-on:
    - name: "ubuntu"
      channel: "20.04"
      architectures: ["arm64"]
    run-on:
    - name: "ubuntu"
      channel: "20.04"
      architectures: ["arm64"]
  - build-on:
    - name: "ubuntu"
      channel: "22.04"
      architectures: ["amd64"]
    run-on:
    - name: "ubuntu"
      channel: "22.04"
      architectures: ["amd64"]
  - build-on:
    - name: "ubuntu"
      channel: "20.04"
      architectures: ["amd64"]
    run-on:
    - name: "ubuntu"
      channel: "20.04"
      architectures: ["amd64"]

parts:
  charm:
    build-packages:
    - git

    # The following are needed for tls-certificates-interface
    - build-essential
    - python3-dev
    - libffi-dev
    - libssl-dev
    - pkg-config
    - rustc
    - cargo
    charm-binary-python-packages:
      # Install PyYAML from binary and avoid building it from sources. This way, we can use PyYAML with C-optimized lib.
      # With the C-optimized lib, serialization in ops is 20x faster.
      - PyYAML
  cos-tool:
    plugin: dump
    source: .
    build-packages:
      - curl
    override-pull: |
      curl -L -O https://github.com/canonical/cos-tool/releases/latest/download/cos-tool-${CRAFT_ARCH_BUILD_FOR}
      chmod 775 cos-tool-*

requires:
  certificates:
    interface: tls-certificates
    limit: 1
    description: |
      Certificate for the grafana agent server (API endpoint is served on :12345 by default)
      to use to authenticate to clients, and the CA certificate of the signing CA.
      We currently assume that the same CA signs all scrape targets (e.g. principal units).
  juju-info:
    description: |
      `juju-info` provides basic compatibility with all charms.
      If all you want is /var/log logs and node_exporter metrics,
      this relation will be enough.
    interface: juju-info
    scope: container
  cos-agent:
    description: |
      `cos-agent` is a dedicated relation for the grafana agent machine
      charm. It will allow you to set up custom scrape jobs, fetch files
      from arbitrary locations, send alert rules, dashboards, etc.
    interface: cos_agent
    scope: container

  send-remote-write:
    interface: prometheus_remote_write
  logging-consumer:
    interface: loki_push_api
  grafana-cloud-config:
    interface: grafana_cloud_config
    limit: 1
  receive-ca-cert:
    interface: certificate_transfer
    description: |
      Obtain TLS information (certificate, ca, chain) from another charm.
  tracing:
    interface: tracing
    limit: 1

provides:
  grafana-dashboards-provider:
    interface: grafana_dashboard

peers:
  peers:
    interface: grafana_agent_replica

config:
  options:
    classic_snap:
      description: |
        Choose whether to use the classic snap over the strictly confined
        one. Defaults to "true".
      type: boolean
      default: true
    tls_insecure_skip_verify:
      description: |
        Flag to skip the verification for insecure TLS.
        If "true", self-signed certs can be seamlessly used; this setting
        will be applied to all of the Agent configurations (Prometheus,
        Loki).
      type: boolean
      default: false
    global_scrape_timeout:
      description: >
        How long to wait before timing out a scrape from a target.
        Supported units: y, w, d, h, m, s.
      type: string
      default: "10s"
    global_scrape_interval:
      description: >
        How frequently should instances be scraped.
        Supported units: y, w, d, h, m, s.
      type: string
      default: "1m"
    always_enable_zipkin:
      description: > 
        Force-enable the receiver for the 'zipkin' protocol in Grafana Agent, 
        even if there is no integration currently requesting it.
      type: boolean
      default: false
    always_enable_otlp_grpc:
      description: > 
        Force-enable the receiver for the 'otlp_grpc' protocol in Grafana Agent, 
        even if there is no integration currently requesting it.
      type: boolean
      default: false
    always_enable_otlp_http:
      description: > 
        Force-enable the receiver for the 'otlp_http' protocol in Grafana Agent, 
        even if there is no integration currently requesting it.
      type: boolean
      default: false
    always_enable_jaeger_grpc:
      description: > 
        Force-enable the receiver for the 'jaeger_grpc' protocol in Grafana Agent, 
        even if there is no integration currently requesting it.
      type: boolean
      default: false
    always_enable_jaeger_thrift_http:
      description: >
        Force-enable the receiver for the 'jaeger_thrift_http' protocol in Grafana Agent, 
        even if there is no integration currently requesting it.
      type: boolean
      default: false
    tracing_sample_rate_charm:
      description: >
        This property defines the percentage of charm traces that are sent to tracing backend.
        Setting it to 100 would mean all charm traces are kept, setting to 0 means charm traces
        aren't sent to tracing backend at all. Anything outside of 0-100 range will be normalised 
        to this range by Grafana Agent.
      type: float
      default: 100.0
    tracing_sample_rate_workload:
      description: >
        This property defines the percentage of workload traces that are sent to tracing backend.
        Setting it to 100 would mean all workload traces are kept, setting to 0 means workload traces
        aren't sent to tracing backend at all. Anything outside of 0-100 range will be normalised 
        to this range by Grafana Agent.
      type: float
      default: 1.0
    tracing_sample_rate_error:
      description: >
        This property defines the percentage of error traces (regardless of the type) that are sent to tracing backend.
        Setting it to 100 would mean all error traces are kept, setting to 0 means error traces
        aren't sent to tracing backend at all. Anything outside of 0-100 range will be normalised 
        to this range by Grafana Agent.
      type: float
      default: 100.0
    reporting_enabled:
      description: |
        Toggle reporting of usage info to grafana, such as enabled feature flags.

        Ref: https://grafana.com/docs/agent/latest/static/configuration/flags/#report-information-usage
      type: boolean
      default: true
    log_level:
      description: |
        Grafana Agent server log level (only log messages with the given severity
        or above). Must be one of: [debug, info, warn, error].
        If not set, the Grafana Agent default (info) will be used.
      type: string
      default: info
    path_exclude:
      description: >
        Glob for a set of log files present in `/var/log` that should be ignored by Grafana Agent.

        For example, `/var/log/**/{app_one,app_two}.log` will result in the agent ignoring both 
        `/var/log/app_one.log` and `/var/log/app_two.log`.

        Note that the value you provide here is not interpreted as a path, but rather as a glob matcher.
        Specifically, if you want to exclude logs in the `/var/log/test` folder, you should set the 
        config to `/var/log/test/**`.

        Ref (__path_exclude__): https://grafana.com/docs/loki/latest/send-data/promtail/scraping/
      type: string
      default: ""