PlantUML Server API

openapi: 3.0.3
info:
  title: PlantUML Server API
  description: >-
    The PlantUML Server provides a public REST API for generating UML and
    non-UML diagrams from plain-text descriptions. The diagram source is
    encoded into the URL path using a deflate + base64 algorithm. Multiple
    output formats are supported including PNG, SVG, ASCII art, and PDF.
  version: 1.0.0
  contact:
    name: PlantUML
    url: https://plantuml.com/
  license:
    name: GPL v3 / MIT dual-license
    url: https://plantuml.com/license
externalDocs:
  description: PlantUML Server API Reference
  url: https://deepwiki.com/plantuml/plantuml-server/6-api-reference
servers:
  - url: https://www.plantuml.com/plantuml
    description: Public PlantUML Server
tags:
  - name: Diagrams
    description: Generate diagrams from encoded PlantUML source
  - name: Validation
    description: Validate PlantUML source syntax
paths:
  /png/{encoded}:
    get:
      operationId: getDiagramPng
      summary: Get Diagram as PNG
      description: >-
        Renders a PlantUML diagram as a PNG image. The encoded parameter is the
        PlantUML source compressed with deflate and encoded in base64url.
      tags:
        - Diagrams
      parameters:
        - name: encoded
          in: path
          required: true
          description: Deflate + base64url encoded PlantUML source
          schema:
            type: string
      responses:
        '200':
          description: PNG image of the rendered diagram
          content:
            image/png:
              schema:
                type: string
                format: binary
        '400':
          description: Invalid or malformed encoded diagram source
  /svg/{encoded}:
    get:
      operationId: getDiagramSvg
      summary: Get Diagram as SVG
      description: >-
        Renders a PlantUML diagram as an SVG image. The encoded parameter is the
        PlantUML source compressed with deflate and encoded in base64url.
      tags:
        - Diagrams
      parameters:
        - name: encoded
          in: path
          required: true
          description: Deflate + base64url encoded PlantUML source
          schema:
            type: string
      responses:
        '200':
          description: SVG image of the rendered diagram
          content:
            image/svg+xml:
              schema:
                type: string
        '400':
          description: Invalid or malformed encoded diagram source
  /txt/{encoded}:
    get:
      operationId: getDiagramAscii
      summary: Get Diagram as ASCII Art
      description: >-
        Renders a PlantUML diagram as ASCII art text. Useful for text-only
        environments or embedding in documentation.
      tags:
        - Diagrams
      parameters:
        - name: encoded
          in: path
          required: true
          description: Deflate + base64url encoded PlantUML source
          schema:
            type: string
      responses:
        '200':
          description: ASCII art text representation of the diagram
          content:
            text/plain:
              schema:
                type: string
        '400':
          description: Invalid or malformed encoded diagram source
  /pdf/{encoded}:
    get:
      operationId: getDiagramPdf
      summary: Get Diagram as PDF
      description: >-
        Renders a PlantUML diagram as a PDF document.
      tags:
        - Diagrams
      parameters:
        - name: encoded
          in: path
          required: true
          description: Deflate + base64url encoded PlantUML source
          schema:
            type: string
      responses:
        '200':
          description: PDF document of the rendered diagram
          content:
            application/pdf:
              schema:
                type: string
                format: binary
        '400':
          description: Invalid or malformed encoded diagram source
  /map/{encoded}:
    get:
      operationId: getDiagramImageMap
      summary: Get Diagram HTML Image Map
      description: >-
        Returns an HTML image map for the diagram, enabling clickable areas
        on diagrams rendered as PNG.
      tags:
        - Diagrams
      parameters:
        - name: encoded
          in: path
          required: true
          description: Deflate + base64url encoded PlantUML source
          schema:
            type: string
      responses:
        '200':
          description: HTML image map for the diagram
          content:
            text/plain:
              schema:
                type: string
        '400':
          description: Invalid or malformed encoded diagram source
  /check/{encoded}:
    get:
      operationId: validateDiagramSyntax
      summary: Validate Diagram Syntax
      description: >-
        Validates the PlantUML source syntax without rendering the diagram.
        Returns a text description of parsing results including any error
        messages.
      tags:
        - Validation
      parameters:
        - name: encoded
          in: path
          required: true
          description: Deflate + base64url encoded PlantUML source
          schema:
            type: string
      responses:
        '200':
          description: Validation result describing parsing success or errors
          content:
            text/plain:
              schema:
                type: string
components:
  schemas:
    DiagramError:
      type: object
      properties:
        error:
          type: string
          description: Error message describing what went wrong
        line:
          type: integer
          description: Line number where the error occurred