Squid Cache Statistics API

openapi: 3.1.0
info:
  title: Squid Cache Manager Cache Statistics API
  description: The Squid Cache Manager is a built-in HTTP management interface that exposes internal statistics, cache operations, and runtime state via HTTP requests. It provides endpoints for retrieving cache statistics, managing connections, viewing counters, and performing cache operations. Access is typically restricted to localhost or authorized IP ranges.
  version: 6.x
  contact:
    name: Squid Project
    url: http://www.squid-cache.org/Support/
  license:
    name: GNU General Public License v2
    url: https://www.gnu.org/licenses/old-licenses/gpl-2.0.html
servers:
- url: http://localhost:3128/squid-internal-mgr
  description: Local Squid Cache Manager (default port)
security:
- BasicAuth: []
tags:
- name: Cache Statistics
  description: Cache performance metrics and counters
paths:
  /info:
    get:
      operationId: getCacheInfo
      summary: Get Cache Information
      description: Returns general information about the Squid process including version, start time, current time, and basic statistics about requests served, cache hits, and memory usage.
      tags:
      - Cache Statistics
      responses:
        '200':
          description: Cache information
          content:
            text/plain:
              schema:
                type: string
                description: Plain text cache information report
        '401':
          description: Unauthorized — cache manager password required
  /counters:
    get:
      operationId: getCacheCounters
      summary: Get Cache Counters
      description: Returns detailed performance counters including request counts, cache hit rates, byte counts, DNS statistics, ICP statistics, and HTTP status breakdowns.
      tags:
      - Cache Statistics
      responses:
        '200':
          description: Performance counters
          content:
            text/plain:
              schema:
                type: string
        '401':
          description: Unauthorized
  /5min:
    get:
      operationId: get5MinStatistics
      summary: Get 5-Minute Statistics
      description: Returns rolling 5-minute averages for cache activity metrics.
      tags:
      - Cache Statistics
      responses:
        '200':
          description: 5-minute rolling statistics
          content:
            text/plain:
              schema:
                type: string
  /60min:
    get:
      operationId: get60MinStatistics
      summary: Get 60-Minute Statistics
      description: Returns rolling 60-minute averages for cache activity metrics.
      tags:
      - Cache Statistics
      responses:
        '200':
          description: 60-minute rolling statistics
          content:
            text/plain:
              schema:
                type: string
  /utilization:
    get:
      operationId: getCacheUtilization
      summary: Get Cache Utilization
      description: Returns current cache utilization including object count, capacity used, and store capacity statistics.
      tags:
      - Cache Statistics
      responses:
        '200':
          description: Cache utilization report
          content:
            text/plain:
              schema:
                type: string
  /store_digest:
    get:
      operationId: getStoreDigest
      summary: Get Cache Store Digest
      description: Returns the cache store digest, a compact representation of cached objects used for ICP/HTCP peer communication.
      tags:
      - Cache Statistics
      responses:
        '200':
          description: Cache store digest
          content:
            application/octet-stream:
              schema:
                type: string
                format: binary
  /objects:
    get:
      operationId: getCacheObjects
      summary: List Cached Objects
      description: Returns a list of objects currently stored in the cache including their URLs, sizes, creation times, and hit counts.
      tags:
      - Cache Statistics
      parameters:
      - name: pattern
        in: query
        description: URL pattern filter (glob)
        schema:
          type: string
      responses:
        '200':
          description: List of cached objects
          content:
            text/plain:
              schema:
                type: string
components:
  securitySchemes:
    BasicAuth:
      type: http
      scheme: basic
      description: Cache manager password configured via cachemgr_passwd in squid.conf