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| 1 | +export interface PredictionData { |
| 2 | + chatflowId: string; |
| 3 | + question: string; |
| 4 | + overrideConfig?: Record<string, any>; |
| 5 | + chatId?: string; |
| 6 | + streaming?: boolean; |
| 7 | +} |
| 8 | + |
| 9 | +interface FlowiseClientOptions { |
| 10 | + baseUrl?: string; |
| 11 | +} |
| 12 | + |
| 13 | +type PredictionResponse<T extends PredictionData> = T['streaming'] extends true |
| 14 | + ? AsyncGenerator<string, void, unknown> // Streaming returns an async generator |
| 15 | + : Record<string, any>; |
| 16 | + |
| 17 | +export default class FlowiseClient { |
| 18 | + private baseUrl: string; |
| 19 | + |
| 20 | + constructor(options: FlowiseClientOptions = {}) { |
| 21 | + this.baseUrl = options.baseUrl || 'http://localhost:3000'; |
| 22 | + } |
| 23 | + |
| 24 | + // Method to create a new prediction and handle streaming response |
| 25 | + async createPrediction<T extends PredictionData>( |
| 26 | + data: T |
| 27 | + ): Promise<PredictionResponse<T>> { |
| 28 | + const { chatflowId, streaming } = data; |
| 29 | + |
| 30 | + // Check if chatflow is available to stream |
| 31 | + const chatFlowStreamingUrl = `${this.baseUrl}/api/v1/chatflows-streaming/${chatflowId}`; |
| 32 | + const resp = await fetch(chatFlowStreamingUrl, { |
| 33 | + method: 'GET', |
| 34 | + headers: { |
| 35 | + 'Content-Type': 'application/json', |
| 36 | + }, |
| 37 | + }); |
| 38 | + |
| 39 | + const chatFlowStreamingData = await resp.json(); |
| 40 | + const isChatFlowAvailableToStream = |
| 41 | + chatFlowStreamingData.isStreaming || false; |
| 42 | + |
| 43 | + const predictionUrl = `${this.baseUrl}/api/v1/prediction/${chatflowId}`; |
| 44 | + |
| 45 | + if (isChatFlowAvailableToStream && streaming) { |
| 46 | + return { |
| 47 | + async *[Symbol.asyncIterator]() { |
| 48 | + const response = await fetch(predictionUrl, { |
| 49 | + method: 'POST', |
| 50 | + headers: { |
| 51 | + 'Content-Type': 'application/json', |
| 52 | + }, |
| 53 | + body: JSON.stringify(data), |
| 54 | + }); |
| 55 | + |
| 56 | + if (!response.ok) { |
| 57 | + throw new Error( |
| 58 | + `HTTP error! status: ${response.status}` |
| 59 | + ); |
| 60 | + } |
| 61 | + |
| 62 | + //@ts-ignore |
| 63 | + const reader = response.body.getReader(); |
| 64 | + const decoder = new TextDecoder(); |
| 65 | + let buffer = ''; |
| 66 | + |
| 67 | + try { |
| 68 | + while (true) { |
| 69 | + const { done, value } = await reader.read(); |
| 70 | + if (done) break; |
| 71 | + |
| 72 | + buffer += decoder.decode(value, { stream: true }); |
| 73 | + const lines = buffer.split('\n'); |
| 74 | + buffer = lines.pop() || ''; |
| 75 | + |
| 76 | + for (const line of lines) { |
| 77 | + if (line.trim() === '') continue; |
| 78 | + if (line.startsWith('data:')) { |
| 79 | + const stringifiedJson = line.replace( |
| 80 | + 'data:', |
| 81 | + '' |
| 82 | + ); |
| 83 | + const event = JSON.parse(stringifiedJson); |
| 84 | + yield event; |
| 85 | + } |
| 86 | + } |
| 87 | + } |
| 88 | + } finally { |
| 89 | + reader.releaseLock(); |
| 90 | + } |
| 91 | + }, |
| 92 | + } as unknown as Promise<PredictionResponse<T>>; |
| 93 | + } else { |
| 94 | + // Make a POST request and handle streaming response |
| 95 | + const options = { |
| 96 | + method: 'POST', |
| 97 | + headers: { |
| 98 | + 'Content-Type': 'application/json', |
| 99 | + }, |
| 100 | + body: JSON.stringify(data), |
| 101 | + }; |
| 102 | + |
| 103 | + try { |
| 104 | + const response = await fetch(predictionUrl, options); |
| 105 | + const resp = await response.json(); |
| 106 | + return resp as Promise<PredictionResponse<T>>; |
| 107 | + } catch (error) { |
| 108 | + throw new Error('Error creating prediction'); |
| 109 | + } |
| 110 | + } |
| 111 | + } |
| 112 | +} |
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