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| 1 | +import { EmbeddingProvider } from './types.js'; |
| 2 | + |
| 3 | +interface OllamaEmbeddingResponse { |
| 4 | + embedding: number[]; |
| 5 | +} |
| 6 | + |
| 7 | +/** |
| 8 | + * Ollama Embedding Provider |
| 9 | + * Supports local embedding models via Ollama API. |
| 10 | + * API endpoint: POST /api/embeddings |
| 11 | + */ |
| 12 | +export class OllamaEmbeddingProvider implements EmbeddingProvider { |
| 13 | + readonly name = 'ollama'; |
| 14 | + |
| 15 | + // Default dimensions for nomic-embed-text (768) |
| 16 | + // Override via EMBEDDING_MODEL env var for other models |
| 17 | + get dimensions(): number { |
| 18 | + // Common Ollama embedding model dimensions |
| 19 | + const modelDimensions: Record<string, number> = { |
| 20 | + 'nomic-embed-text': 768, |
| 21 | + 'nomic-embed-text:latest': 768, |
| 22 | + 'mxbai-embed-large': 1024, |
| 23 | + 'mxbai-embed-large:latest': 1024, |
| 24 | + 'all-minilm': 384, |
| 25 | + 'all-minilm:latest': 384, |
| 26 | + }; |
| 27 | + return modelDimensions[this.modelName] || 768; |
| 28 | + } |
| 29 | + |
| 30 | + constructor( |
| 31 | + readonly modelName: string = 'nomic-embed-text', |
| 32 | + private apiEndpoint: string = 'http://localhost:11434' |
| 33 | + ) {} |
| 34 | + |
| 35 | + async initialize(): Promise<void> { |
| 36 | + // Ollama doesn't require an API key |
| 37 | + // We could test connectivity here if needed |
| 38 | + } |
| 39 | + |
| 40 | + isReady(): boolean { |
| 41 | + // Ollama is always "ready" - no auth required |
| 42 | + return true; |
| 43 | + } |
| 44 | + |
| 45 | + async embed(text: string): Promise<number[]> { |
| 46 | + const batch = await this.embedBatch([text]); |
| 47 | + return batch[0]; |
| 48 | + } |
| 49 | + |
| 50 | + async embedBatch(texts: string[]): Promise<number[][]> { |
| 51 | + if (!texts.length) return []; |
| 52 | + |
| 53 | + const embeddings: number[][] = []; |
| 54 | + |
| 55 | + // Ollama embeddings API processes one text at a time |
| 56 | + for (const text of texts) { |
| 57 | + try { |
| 58 | + const response = await fetch(`${this.apiEndpoint}/api/embeddings`, { |
| 59 | + method: 'POST', |
| 60 | + headers: { |
| 61 | + 'Content-Type': 'application/json', |
| 62 | + }, |
| 63 | + body: JSON.stringify({ |
| 64 | + model: this.modelName, |
| 65 | + prompt: text, |
| 66 | + }), |
| 67 | + }); |
| 68 | + |
| 69 | + if (!response.ok) { |
| 70 | + const error = await response.text(); |
| 71 | + throw new Error(`Ollama API Error ${response.status}: ${error}`); |
| 72 | + } |
| 73 | + |
| 74 | + const data = (await response.json()) as OllamaEmbeddingResponse; |
| 75 | + embeddings.push(data.embedding); |
| 76 | + } catch (error) { |
| 77 | + console.error('Ollama Embedding Failed:', error); |
| 78 | + throw error; |
| 79 | + } |
| 80 | + } |
| 81 | + |
| 82 | + return embeddings; |
| 83 | + } |
| 84 | +} |
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