openapi: 3.0.3
info:
  title: Fluent Bit Monitoring HTTP API
  description: >-
    Fluent Bit exposes an embedded HTTP server for runtime monitoring, internal
    metrics, storage statistics, health checks, and hot reloading. Endpoints are
    available under v1 (legacy) and v2 (current) paths and respond in JSON,
    Prometheus 0.0.4, or cmetrics text format.
  version: "2.0.0"
  contact:
    name: Fluent Bit
    url: https://docs.fluentbit.io/manual/administration/monitoring
servers:
  - url: http://127.0.0.1:2020
    description: Default HTTP server (configurable via http_listen and http_port)
tags:
  - name: Build
  - name: Uptime
  - name: Metrics
  - name: Storage
  - name: Health
  - name: Reload
paths:
  /:
    get:
      tags: [Build]
      summary: Build information
      description: Returns Fluent Bit build information.
      responses:
        "200":
          description: Build info
          content:
            application/json:
              schema:
                type: object
                properties:
                  fluent-bit:
                    type: object
                    properties:
                      version:
                        type: string
                      edition:
                        type: string
                      flags:
                        type: array
                        items:
                          type: string
  /api/v1/uptime:
    get:
      tags: [Uptime]
      summary: Uptime information
      responses:
        "200":
          description: Uptime in seconds and human form
          content:
            application/json:
              schema:
                type: object
                properties:
                  uptime_sec:
                    type: integer
                  uptime_hr:
                    type: string
  /api/v1/metrics:
    get:
      tags: [Metrics]
      summary: Internal metrics (v1, JSON)
      description: Display internal metrics per loaded plugin.
      responses:
        "200":
          description: Plugin metrics
          content:
            application/json:
              schema:
                type: object
                properties:
                  input:
                    type: object
                    additionalProperties: true
                  filter:
                    type: object
                    additionalProperties: true
                  output:
                    type: object
                    additionalProperties: true
  /api/v1/metrics/prometheus:
    get:
      tags: [Metrics]
      summary: Internal metrics (v1, Prometheus)
      responses:
        "200":
          description: Prometheus 0.0.4 exposition
          content:
            text/plain; version=0.0.4:
              schema:
                type: string
  /api/v1/storage:
    get:
      tags: [Storage]
      summary: Storage layer metrics
      description: Buffered data and chunk-level statistics for the storage layer.
      responses:
        "200":
          description: Storage metrics
          content:
            application/json:
              schema:
                type: object
                additionalProperties: true
  /api/v1/health:
    get:
      tags: [Health]
      summary: Health check (v1)
      responses:
        "200":
          description: Health string
          content:
            text/plain:
              schema:
                type: string
  /api/v2/metrics:
    get:
      tags: [Metrics]
      summary: Internal metrics (v2, cmetrics)
      responses:
        "200":
          description: cmetrics text exposition
          content:
            text/plain:
              schema:
                type: string
  /api/v2/metrics/prometheus:
    get:
      tags: [Metrics]
      summary: Internal metrics (v2, Prometheus)
      responses:
        "200":
          description: Prometheus 0.0.4 exposition
          content:
            text/plain; version=0.0.4:
              schema:
                type: string
  /api/v2/health:
    get:
      tags: [Health]
      summary: Health status (v2, JSON)
      responses:
        "200":
          description: Healthy
          content:
            application/json:
              schema:
                type: object
                properties:
                  status:
                    type: string
                    example: ok
        "500":
          description: Unhealthy
          content:
            application/json:
              schema:
                type: object
                properties:
                  status:
                    type: string
                    example: error
  /api/v2/reload:
    get:
      tags: [Reload]
      summary: Get hot reload status
      responses:
        "200":
          description: Reload status
          content:
            application/json:
              schema:
                type: object
                properties:
                  status:
                    type: string
                  in_progress:
                    type: boolean
    post:
      tags: [Reload]
      summary: Trigger hot reload
      responses:
        "200":
          description: Reload triggered
          content:
            application/json:
              schema:
                type: object
                properties:
                  status:
                    type: string
    put:
      tags: [Reload]
      summary: Trigger hot reload (PUT)
      responses:
        "200":
          description: Reload triggered
          content:
            application/json:
              schema:
                type: object
                properties:
                  status:
                    type: string