feat(server): add uptime tracking to root endpoint

Display server uptime on GET / endpoint with formatted output (days, hours, minutes, seconds).
Records start time in state when server starts.

Author: sachnun

src/lib/state.ts

@@ -15,6 +15,9 @@ export interface State {
   // Rate limiting configuration
   rateLimitSeconds?: number
   lastRequestTimestamp?: number
+
+  // Server uptime tracking
+  serverStartTime?: number
 }
 
 export const state: State = {

src/server.ts

@@ -2,6 +2,7 @@ import { Hono } from "hono"
 import { cors } from "hono/cors"
 import { logger } from "hono/logger"
 
+import { state } from "./lib/state"
 import { completionRoutes } from "./routes/chat-completions/route"
 import { embeddingRoutes } from "./routes/embeddings/route"
 import { messageRoutes } from "./routes/messages/route"
@@ -10,12 +11,40 @@ import { responsesRoutes } from "./routes/responses/route"
 import { tokenRoute } from "./routes/token/route"
 import { usageRoute } from "./routes/usage/route"
 
+function formatUptime(milliseconds: number): string {
+  const seconds = Math.floor(milliseconds / 1000)
+  const minutes = Math.floor(seconds / 60)
+  const hours = Math.floor(minutes / 60)
+  const days = Math.floor(hours / 24)
+
+  if (days > 0) {
+    const remainingHours = hours % 24
+    return `${days}d ${remainingHours}h`
+  }
+  if (hours > 0) {
+    const remainingMinutes = minutes % 60
+    return `${hours}h ${remainingMinutes}m`
+  }
+  if (minutes > 0) {
+    const remainingSeconds = seconds % 60
+    return `${minutes}m ${remainingSeconds}s`
+  }
+  return `${seconds}s`
+}
+
 export const server = new Hono()
 
 server.use(logger())
 server.use(cors())
 
-server.get("/", (c) => c.text("Server running"))
+server.get("/", (c) => {
+  if (state.serverStartTime) {
+    const uptime = Date.now() - state.serverStartTime
+    const uptimeStr = formatUptime(uptime)
+    return c.text(`Already running since ${uptimeStr} ago`)
+  }
+  return c.text("Server running")
+})
 
 server.route("/chat/completions", completionRoutes)
 server.route("/models", modelRoutes)

src/start.ts

@@ -114,6 +114,10 @@ export async function runServer(options: RunServerOptions): Promise<void> {
     `🌐 Usage Viewer: https://ericc-ch.github.io/copilot-api?endpoint=${serverUrl}/usage`,
   )
 
+  // Record server start time
+  // eslint-disable-next-line require-atomic-updates
+  state.serverStartTime = Date.now()
+
   serve({
     fetch: server.fetch as ServerHandler,
     port: options.port,