Initial commit

2025-11-30 08:24:54 +08:00
commit 7927519669
17 changed files with 4377 additions and 0 deletions
--- a/templates/embeddings-fetch.ts
+++ b/templates/embeddings-fetch.ts
@@ -0,0 +1,157 @@
+/**
+ * Gemini Embeddings with Fetch (Cloudflare Workers)
+ *
+ * Demonstrates embedding generation using fetch API instead of SDK.
+ * Perfect for Cloudflare Workers and edge environments.
+ *
+ * Setup:
+ * 1. Add GEMINI_API_KEY to wrangler.jsonc secrets
+ * 2. npx wrangler secret put GEMINI_API_KEY
+ * 3. Deploy: npx wrangler deploy
+ *
+ * Usage:
+ * GET /?text=your+text+here
+ */
+
+interface Env {
+  GEMINI_API_KEY: string;
+}
+
+interface EmbeddingRequest {
+  content: {
+    parts: Array<{ text: string }>;
+  };
+  taskType?: string;
+  outputDimensionality?: number;
+}
+
+interface EmbeddingResponse {
+  embedding: {
+    values: number[];
+  };
+}
+
+export default {
+  async fetch(request: Request, env: Env): Promise<Response> {
+    // CORS headers for browser access
+    const corsHeaders = {
+      'Access-Control-Allow-Origin': '*',
+      'Access-Control-Allow-Methods': 'GET, POST, OPTIONS',
+      'Access-Control-Allow-Headers': 'Content-Type'
+    };
+
+    // Handle CORS preflight
+    if (request.method === 'OPTIONS') {
+      return new Response(null, { headers: corsHeaders });
+    }
+
+    try {
+      // Get text from query param or request body
+      const url = new URL(request.url);
+      let text: string;
+
+      if (request.method === 'POST') {
+        const body = await request.json<{ text: string }>();
+        text = body.text;
+      } else {
+        text = url.searchParams.get('text') || 'What is the meaning of life?';
+      }
+
+      console.log(`Generating embedding for: "${text}"`);
+
+      // Prepare request
+      const embeddingRequest: EmbeddingRequest = {
+        content: {
+          parts: [{ text }]
+        },
+        taskType: 'SEMANTIC_SIMILARITY',
+        outputDimensionality: 768
+      };
+
+      // Call Gemini API
+      const response = await fetch(
+        'https://generativelanguage.googleapis.com/v1beta/models/gemini-embedding-001:embedContent',
+        {
+          method: 'POST',
+          headers: {
+            'x-goog-api-key': env.GEMINI_API_KEY,
+            'Content-Type': 'application/json'
+          },
+          body: JSON.stringify(embeddingRequest)
+        }
+      );
+
+      if (!response.ok) {
+        const error = await response.text();
+        throw new Error(`Gemini API error: ${response.status} - ${error}`);
+      }
+
+      const data = await response.json<EmbeddingResponse>();
+      const embedding = data.embedding.values;
+
+      // Calculate vector magnitude
+      const magnitude = Math.sqrt(
+        embedding.reduce((sum, v) => sum + v * v, 0)
+      );
+
+      // Return formatted response
+      return new Response(JSON.stringify({
+        success: true,
+        text,
+        embedding: {
+          dimensions: embedding.length,
+          magnitude: magnitude.toFixed(4),
+          firstValues: embedding.slice(0, 10).map(v => parseFloat(v.toFixed(4))),
+          fullVector: embedding
+        }
+      }, null, 2), {
+        headers: {
+          'Content-Type': 'application/json',
+          ...corsHeaders
+        }
+      });
+
+    } catch (error: any) {
+      console.error('Error:', error.message);
+
+      return new Response(JSON.stringify({
+        success: false,
+        error: error.message,
+        hint: error.message.includes('401')
+          ? 'Check GEMINI_API_KEY secret is set'
+          : error.message.includes('429')
+          ? 'Rate limit exceeded (Free tier: 100 RPM)'
+          : 'Check error message for details'
+      }, null, 2), {
+        status: 500,
+        headers: {
+          'Content-Type': 'application/json',
+          ...corsHeaders
+        }
+      });
+    }
+  }
+};
+
+/**
+ * Example wrangler.jsonc configuration:
+ *
+ * {
+ *   "name": "gemini-embeddings-worker",
+ *   "main": "src/index.ts",
+ *   "compatibility_date": "2025-10-25",
+ *   "vars": {
+ *     "ENVIRONMENT": "production"
+ *   }
+ * }
+ *
+ * Set secret:
+ * npx wrangler secret put GEMINI_API_KEY
+ *
+ * Test locally:
+ * npx wrangler dev
+ * curl "http://localhost:8787/?text=Hello+world"
+ *
+ * Deploy:
+ * npx wrangler deploy
+ */