Switch to Express

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src/node/app.ts

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+import { logger } from "@coder/logger"
+import express, { Express } from "express"
+import { promises as fs } from "fs"
+import http from "http"
+import * as httpolyglot from "httpolyglot"
+import { DefaultedArgs } from "./cli"
+
+/**
+ * Create an Express app and an HTTP/S server to serve it.
+ */
+export const createApp = async (args: DefaultedArgs): Promise<[Express, http.Server]> => {
+  const app = express()
+
+  const server = args.cert
+    ? httpolyglot.createServer(
+        {
+          cert: args.cert && (await fs.readFile(args.cert.value)),
+          key: args["cert-key"] && (await fs.readFile(args["cert-key"])),
+        },
+        app,
+      )
+    : http.createServer(app)
+
+  await new Promise<http.Server>(async (resolve, reject) => {
+    server.on("error", reject)
+    if (args.socket) {
+      try {
+        await fs.unlink(args.socket)
+      } catch (error) {
+        if (error.code !== "ENOENT") {
+          logger.error(error.message)
+        }
+      }
+      server.listen(args.socket, resolve)
+    } else {
+      // [] is the correct format when using :: but Node errors with them.
+      server.listen(args.port, args.host.replace(/^\[|\]$/g, ""), resolve)
+    }
+  })
+
+  return [app, server]
+}
+
+/**
+ * Get the address of a server as a string (protocol not included) while
+ * ensuring there is one (will throw if there isn't).
+ */
+export const ensureAddress = (server: http.Server): string => {
+  const addr = server.address()
+  if (!addr) {
+    throw new Error("server has no address")
+  }
+  if (typeof addr !== "string") {
+    return `${addr.address}:${addr.port}`
+  }
+  return addr
+}