概要

(自分メモ)
実際の要求と応答をGeminiに与えopenapi定義ファイルを生成し、swagger codegenでクライアントコードを生成しkotlinで使用する例
楽だわ

環境

Windows 11
Gemini 2.0 flash (Gemini API Key を用意) ※APIではgemini-1.5-flashを使用
Java 21

OpenAPI定義ファイル作成

Geminiに自身のQuick Startページから定義を作るよう依頼し..

下記要求と応答を表現するopenapi3.0.yamlを生成して
- データ型はschemas:として定義
- keyは全API共通なのでのsecurity:に定義

要求:
curl -X POST "https://generativelanguage.googleapis.com/v1beta/models/gemini-1.5-flash:generateContent?key=YOUR_API_KEY" \
-H 'Content-Type: application/json' \
-d '{"contents": [{"parts":[{"text": "Write a story about a magic backpack."}]}]}'

応答:
{
  "candidates": 
  # ..中略..
  "modelVersion": "gemini-1.5-flash"
}

...て作ってもらった gemini.yml

openapi: 3.0.0
info:
  title: Gemini API
  version: v1beta
servers:
  - url: 'https://generativelanguage.googleapis.com/v1beta'
components:
  schemas:
    Part:
      type: object
      properties:
        text:
          type: string
    Content:
      type: object
      properties:
        parts:
          type: array
          items:
            $ref: '#/components/schemas/Part'
        role:
          type: string
    Candidate:
      type: object
      properties:
        content:
          $ref: '#/components/schemas/Content'
        finishReason:
          type: string
        avgLogprobs:
          type: number
          format: float
    UsageMetadata:
      type: object
      properties:
        promptTokenCount:
          type: integer
        candidatesTokenCount:
          type: integer
        totalTokenCount:
          type: integer
    GenerateContentRequest:
      type: object
      properties:
        contents:
          type: array
          items:
            type: object
            properties:
              parts:
                type: array
                items:
                  $ref: '#/components/schemas/Part'
    GenerateContentResponse:
      type: object
      properties:
        candidates:
          type: array
          items:
            $ref: '#/components/schemas/Candidate'
        usageMetadata:
          $ref: '#/components/schemas/UsageMetadata'
        modelVersion:
          type: string
  securitySchemes:
    ApiKeyAuth:
      type: apiKey
      in: query
      name: key
paths:
  '/models/gemini-1.5-flash:generateContent':
    post:
      description: desc
      summary: Generates content using the Gemini model.
      operationId: generateContent # ※
      requestBody:
        content:
          application/json:
            schema:
              $ref: '#/components/schemas/GenerateContentRequest'
      responses:
        '200':
          description: Successful response
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/GenerateContentResponse'
      security: []
      parameters:
        - schema:
            type: string
          in: query
          name: key
          required: true

※一部呼び出し側に合うよう調整

  '/models/gemini-1.5-flash:generateContent':
    post:
      description: desc
      summary: Generates content using the Gemini model.
+     operationId: generateContent

Swaggerに突っ込んで実行できることを確認 ➜

ソース

App.kt(抜粋)

expect val GEMINI_API_KEY: String

suspend fun appGemini() {
    val client = HttpClient { install(ContentNegotiation) { json(Json) } }
    val api = DefaultApi("https://generativelanguage.googleapis.com/v1beta", client)
    val prompt = "GeminiとOpenAPIに関する今日のTipsを一つ教えて"
    val req = GenerateContentRequest(listOf(GenerateContentRequestContentsInner(listOf(Part(prompt)))))
    val res = api.generateContent(GEMINI_API_KEY, req).body()
    println(Json.encodeToString(res.candidates?.get(0)?.content?.parts?.get(0)?.text))
    client.close()
}

全ソース

テスト実行

GEMINI_API_KEY='AIza************'
sh gradlew jvmRun -DmainClass=MainKt  # jvmの場合
sh gradlew jsNodeRun                  # node.jsの場合

Build & Run

(メモ)ローカルでSwagger Editor

wget https://github.com/swagger-api/swagger-editor/archive/refs/tags/v4.14.1.zip
unzip v4.14.1.zip

ブラウザに./index.htmlを放り込む

参考

OpenAPI Generator
Gradleプラグイン