feat: add ports to code

docker/libraries/exec.ts

@@ -1,4 +1,4 @@
-import delay from "delay";
+import { delay } from "std/async/delay.ts";
 
 import { modem } from "./modem.ts";
 

docker/libraries/port.ts

@@ -0,0 +1,92 @@
+export const MIN_PORT = 1024;
+export const MAX_PORT = 65535;
+
+/**
+ * Try run listener to check if port is open.
+ *
+ * @param options
+ */
+export function checkPort(options: Deno.ListenOptions): CheckedPort {
+  const { port } = options;
+  try {
+    Deno.listen(options).close();
+    return { valid: true, port: port };
+  } catch (e) {
+    if (e.name !== "AddrInUse") {
+      throw e;
+    }
+    return { valid: false, port: port };
+  }
+}
+
+/**
+ * Create an array of number by min and max.
+ *
+ * @param from - Must be between 1024 and 65535
+ * @param to   - Must be between 1024 and 65535 and greater than from
+ */
+export function makeRange(from: number, to: number): number[] {
+  if (!(from > MIN_PORT || from < MAX_PORT)) {
+    throw new RangeError("`from` must be between 1024 and 65535");
+  }
+  if (!(to > MIN_PORT || to < MAX_PORT)) {
+    throw new RangeError("`to` must be between 1024 and 65536");
+  }
+  if (!(to > from)) {
+    throw new RangeError("`to` must be greater than or equal to `from`");
+  }
+  const ports = [];
+  for (let port = from; port <= to; port++) {
+    ports.push(port);
+  }
+  return ports;
+}
+
+/**
+ * Return a random port between 1024 and 65535.
+ *
+ * @param hostname
+ */
+export function randomPort(hostname?: string): number {
+  const port = Math.ceil(Math.random() * ((MAX_PORT - 1) - MIN_PORT + 1) + MIN_PORT + 1);
+  const result: CheckedPort = checkPort({ hostname, port });
+  if (result.valid) {
+    return result.port;
+  }
+  return randomPort(hostname);
+}
+
+/**
+ * Return available port.
+ *
+ * @param port
+ * @param hostname
+ */
+export default function getPort(port?: number | number[], hostname?: string): number {
+  const listenOptions: Deno.ListenOptions = {
+    hostname: hostname || "0.0.0.0",
+    port: (port && !Array.isArray(port)) ? port : 0,
+  };
+
+  if (!port || Array.isArray(port)) {
+    const ports: number[] = (Array.isArray(port)) ? port : makeRange(MIN_PORT + 1, MAX_PORT - 1);
+    for (const port of ports) {
+      const result: CheckedPort = checkPort({ ...listenOptions, port });
+      if (result.valid) return result.port;
+    }
+    return getPort(ports[ports.length - 1]);
+  }
+
+  const result: CheckedPort = checkPort(listenOptions);
+  if (!result.valid) {
+    const range = makeRange(result.port + 1, MAX_PORT - 1);
+    return getPort(range);
+  }
+
+  return result.port;
+}
+
+export type CheckedPort = {
+  valid: boolean;
+  port: number;
+};