Files
page-agent/packages/llms/src/index.ts

93 lines
2.7 KiB
TypeScript

import { OpenAIClient } from './OpenAIClient'
import { DEFAULT_TEMPERATURE, LLM_MAX_RETRIES } from './constants'
import { InvokeError, InvokeErrorTypes } from './errors'
import type { InvokeOptions, InvokeResult, LLMClient, LLMConfig, Message, Tool } from './types'
export { InvokeError, InvokeErrorTypes }
export type { InvokeOptions, InvokeResult, LLMClient, LLMConfig, Message, Tool }
export function parseLLMConfig(config: LLMConfig): Required<LLMConfig> {
// Runtime validation as defensive programming (types already guarantee these)
if (!config.baseURL || !config.model) {
throw new Error(
'[PageAgent] LLM configuration required. Please provide: baseURL, model. ' +
'See: https://alibaba.github.io/page-agent/docs/features/models'
)
}
return {
baseURL: config.baseURL,
model: config.model,
apiKey: config.apiKey || '',
temperature: config.temperature ?? DEFAULT_TEMPERATURE,
maxRetries: config.maxRetries ?? LLM_MAX_RETRIES,
transformRequestBody: config.transformRequestBody ?? ((requestBody) => requestBody),
disableNamedToolChoice: config.disableNamedToolChoice ?? false,
customFetch: (config.customFetch ?? fetch).bind(globalThis), // fetch will be illegal unless bound
}
}
export class LLM extends EventTarget {
config: Required<LLMConfig>
client: LLMClient
constructor(config: LLMConfig) {
super()
this.config = parseLLMConfig(config)
// Default to OpenAI client
this.client = new OpenAIClient(this.config)
}
/**
* - call llm api *once*
* - invoke tool call *once*
* - return the result of the tool
*/
async invoke(
messages: Message[],
tools: Record<string, Tool>,
abortSignal: AbortSignal,
options?: InvokeOptions
): Promise<InvokeResult> {
return await withRetry(async () => this.client.invoke(messages, tools, abortSignal, options), {
maxRetries: this.config.maxRetries,
onRetry: (attempt, lastError) => {
this.dispatchEvent(
new CustomEvent('retry', {
detail: { attempt, maxAttempts: this.config.maxRetries, lastError },
})
)
},
})
}
}
/**
* Retry a function until it succeeds or reaches the maximum number of retries.
*/
async function withRetry<T>(
fn: () => Promise<T>,
settings: {
maxRetries: number
onRetry: (attempt: number, lastError: Error) => void
}
): Promise<T> {
let attempt = 0
while (true) {
try {
return await fn()
} catch (error: unknown) {
if ((error as any)?.name === 'AbortError') throw error
if (error instanceof InvokeError && !error.retryable) throw error
attempt++
if (attempt > settings.maxRetries) throw error
console.debug('[LLM] retryable failure, will retry:', error)
settings.onRetry(attempt, error as Error)
await new Promise((resolve) => setTimeout(resolve, 100))
}
}
}