deno serve

deno serve [OPTIONS] [SCRIPT_ARG]...

deno serve server.ts

deno serve --watch --port 5050 server.ts

Type checking options Jump to heading#

--check Jump to heading#

Enable type-checking. This subcommand does not type-check by default If the value of "all" is supplied, remote modules will be included. Alternatively, the 'deno check' subcommand can be used.

--no-check Jump to heading#

Skip type-checking. If the value of "remote" is supplied, diagnostic errors from remote modules will be ignored.

Dependency management options Jump to heading#

--cached-only Jump to heading#

Require that remote dependencies are already cached.

--frozen Jump to heading#

Error out if lockfile is out of date.

--import-map Jump to heading#

Load import map file from local file or remote URL.

--lock Jump to heading#

Check the specified lock file. (If value is not provided, defaults to "./deno.lock").

--no-lock Jump to heading#

Disable auto discovery of the lock file.

--no-npm Jump to heading#

Do not resolve npm modules.

--no-remote Jump to heading#

Do not resolve remote modules.

--node-modules-dir Jump to heading#

Sets the node modules management mode for npm packages.

--reload Jump to heading#

Short flag: -r

Reload source code cache (recompile TypeScript) no value Reload everything jsr:@std/http/file-server,jsr:@std/assert/assert-equals Reloads specific modules npm: Reload all npm modules npm:chalk Reload specific npm module.

--vendor Jump to heading#

Toggles local vendor folder usage for remote modules and a node_modules folder for npm packages.

Options Jump to heading#

--allow-scripts Jump to heading#

Allow running npm lifecycle scripts for the given packages Note: Scripts will only be executed when using a node_modules directory (--node-modules-dir).

--cert Jump to heading#

Load certificate authority from PEM encoded file.

--config Jump to heading#

Short flag: -c

Configure different aspects of deno including TypeScript, linting, and code formatting Typically the configuration file will be called deno.json or deno.jsonc and automatically detected; in that case this flag is not necessary.

--env-file Jump to heading#

Load environment variables from local file Only the first environment variable with a given key is used. Existing process environment variables are not overwritten.

--ext Jump to heading#

Set content type of the supplied file.

--host Jump to heading#

The TCP address to serve on, defaulting to 0.0.0.0 (all interfaces).

--location Jump to heading#

Value of globalThis.location used by some web APIs.

--no-code-cache Jump to heading#

Disable V8 code cache feature.

--no-config Jump to heading#

Disable automatic loading of the configuration file.

--parallel Jump to heading#

Run multiple server workers in parallel. Parallelism defaults to the number of available CPUs or the value of the DENO_JOBS environment variable.

--port Jump to heading#

The TCP port to serve on. Pass 0 to pick a random free port [default: 8000]

--seed Jump to heading#

Set the random number generator seed.

--v8-flags Jump to heading#

To see a list of all available flags use --v8-flags=--help Flags can also be set via the DENO_V8_FLAGS environment variable. Any flags set with this flag are appended after the DENO_V8_FLAGS environment variable.

Debugging options Jump to heading#

--inspect Jump to heading#

Activate inspector on host:port [default: 127.0.0.1:9229]

--inspect-brk Jump to heading#

Activate inspector on host:port, wait for debugger to connect and break at the start of user script.

--inspect-wait Jump to heading#

Activate inspector on host:port and wait for debugger to connect before running user code.

File watching options Jump to heading#

--hmr Jump to heading#

Watch for file changes and restart process automatically. Local files from entry point module graph are watched by default. Additional paths might be watched by passing them as arguments to this flag.

--no-clear-screen Jump to heading#

Do not clear terminal screen when under watch mode.

--watch Jump to heading#

Watch for file changes and restart process automatically. Local files from entry point module graph are watched by default. Additional paths might be watched by passing them as arguments to this flag.

--watch-exclude Jump to heading#

Exclude provided files/patterns from watch mode.

Example Jump to heading#

Here's an example of how you can create a simple HTTP server with declarative fetch:

export default {
  async fetch(_req) {
    return new Response("Hello world!");
  },
};

You can then run the server using the deno serve command:

deno serve server.ts

The logic inside the fetch function can be customized to handle different types of requests and serve content accordingly:

export default {
  async fetch(request) {
    if (request.url.startsWith("/json")) {
      return Response.json({ hello: "world" });
    }

    return new Response("Hello world!");
  },
};