feat: Enhance logging functionality and update CLI description

Author: ericc-ch

src/lib/cli.ts

@@ -21,7 +21,8 @@ const args = {
   logs: {
     type: "boolean",
     default: false,
-    description: "Write logs to the app directory",
+    description:
+      "Write logs to the app directory. Only works with emulate-streaming",
   },
 } satisfies ArgsDef
 

src/lib/logger.ts

@@ -1,17 +1,17 @@
-import fs from "node:fs"
+import fs from "node:fs/promises"
 
 import { CONFIG } from "~/config/config"
 import { PATHS } from "~/config/paths"
 
 export function initializeLogger() {
   if (!CONFIG.LOGGING_ENABLED) return
 
-  fs.mkdirSync(PATHS.LOG_PATH, { recursive: true })
+  return fs.mkdir(PATHS.LOG_PATH, { recursive: true })
 }
 
-export function logToFile(type: string, message: string) {
+export async function logToFile(type: string, message: string) {
   if (!CONFIG.LOGGING_ENABLED) return
 
   const timestamp = new Date().toISOString()
-  fs.appendFileSync(PATHS.LOG_FILE, `${timestamp} ${type}: ${message}\n`)
+  await fs.appendFile(PATHS.LOG_FILE, `${timestamp} ${type}: ${message}\n`)
 }

src/routes/chat-completions/handler.ts

@@ -5,6 +5,7 @@ import { streamSSE } from "hono/streaming"
 
 import type { ChatCompletionsPayload } from "~/services/copilot/chat-completions/types"
 
+import { logToFile } from "~/lib/logger"
 import { chatCompletions } from "~/services/copilot/chat-completions/service"
 
 import { createContentChunk, createFinalChunk, segmentResponse } from "./utils"
@@ -22,8 +23,10 @@ export async function handler(c: Context) {
   }))
 
   consola.info("Received request:", loggedPayload)
+  await logToFile("REQUEST", JSON.stringify(payload, null, 2))
 
   const response = await chatCompletions(payload)
+  await logToFile("RESPONSE", JSON.stringify(response, null, 2))
 
   if (payload.stream) {
     consola.info(`Response from Copilot: ${JSON.stringify(response)}`)