[](https://www.npmjs.org/package/local-web-server)
[](https://www.npmjs.org/package/local-web-server)
[](https://travis-ci.org/75lb/local-web-server)
[](https://david-dm.org/75lb/local-web-server)
[](https://github.com/feross/standard)
[](https://gitter.im/75lb/local-web-server?utm_source=badge&utm_medium=badge&utm_campaign=pr-badge&utm_content=badge)
***Requires node v4.0.0 or higher. Install the [previous release](https://github.com/75lb/local-web-server/tree/prev) for older node support.***
# local-web-server
A simple web-server for productive front-end development. Typical use cases:
* Front-end Development
* Static or Single Page App development
* Re-route paths to local or remote resources
* Efficient, predictable, entity-tag-powered conditional request handling (no need to 'Disable Cache' in DevTools, slowing page-load down)
* Bundle with your front-end project
* Very little configuration, just a few options
* Outputs a dynamic statistics view to the terminal
* Configurable log output, compatible with [Goaccess, Logstalgia and glTail](https://github.com/75lb/local-web-server/blob/master/doc/visualisation.md)
* Back-end service mocking
* Prototype a web service, microservice, REST API etc.
* Mocks are defined with config (static), or code (dynamic).
* CORS-friendly, all origins allowed by default.
* Proxy server
* Map local routes to remote servers. Removes CORS pain when consuming remote services.
* HTTPS server
* HTTPS is strictly required by some modern techs (ServiceWorker, Media Capture and Streams etc.)
* File sharing
## Synopsis
local-web-server is a simple command-line tool. To use it, from your project directory run `ws`.
$ ws --help
local-web-server
A simple web-server for productive front-end development.
Synopsis
$ ws [<server options>]
$ ws --config
$ ws --help
Server
-p, --port number Web server port.
-d, --directory path Root directory, defaults to the current directory.
-f, --log-format string If a format is supplied an access log is written to stdout. If
not, a dynamic statistics view is displayed. Use a preset ('none',
'dev','combined', 'short', 'tiny' or 'logstalgia') or supply a
custom format (e.g. ':method -> :url').
-r, --rewrite expression ... A list of URL rewrite rules. For each rule, separate the 'from'
and 'to' routes with '->'. Whitespace surrounded the routes is
ignored. E.g. '/from -> /to'.
-s, --spa file Path to a Single Page App, e.g. app.html.
-c, --compress Serve gzip-compressed resources, where applicable.
-b, --forbid path ... A list of forbidden routes.
-n, --no-cache Disable etag-based caching -forces loading from disk each request.
--key file SSL key. Supply along with --cert to launch a https server.
--cert file SSL cert. Supply along with --key to launch a https server.
--https Enable HTTPS using a built-in key and cert, registered to the
domain 127.0.0.1.
--verbose Verbose output, useful for debugging.
Misc
-h, --help Print these usage instructions.
--config Print the stored config.
Project home: https://github.com/75lb/local-web-server
## Examples
For the examples below, we assume we're in a project directory looking like this:
```sh
.
├── css
│ └── style.css
├── index.html
└── package.json
```
All paths/routes are specified using [express syntax](http://expressjs.com/guide/routing.html#route-paths). To run the example projects linked below, clone the project, move into the example directory specified, run `ws`.
### Static site
Fire up your static site on the default port:
```sh
$ ws
serving at http://localhost:8000
```
[Example](https://github.com/75lb/local-web-server/tree/master/example/simple).
### Single Page Application
You're building a web app with client-side routing, so mark `index.html` as the SPA.
```sh
$ ws --spa index.html
```
By default, typical SPA paths (e.g. `/user/1`, `/login`) would return `404 Not Found` as a file does not exist with that path. By marking `index.html` as the SPA you create this rule:
*If a static file at the requested path exists (e.g. `/css/style.css`) then serve it, if it does not (e.g. `/login`) then serve the specified SPA and handle the route client-side.*
[Example](https://github.com/75lb/local-web-server/tree/master/example/spa).
### URL rewriting
Your application requested `/css/style.css` but it's stored at `/build/css/style.css`. To avoid a 404 you need a rewrite rule:
```sh
$ ws --rewrite '/css/style.css -> /build/css/style.css'
```
Or, more generally (matching any stylesheet under `/css`):
```sh
$ ws --rewrite '/css/:stylesheet -> /build/css/:stylesheet'
```
With a deep CSS directory structure it may be easier to mount the entire contents of `/build/css` to the `/css` path:
```sh
$ ws --rewrite '/css/* -> /build/css/$1'
```
this rewrites `/css/a` as `/build/css/a`, `/css/a/b/c` as `/build/css/a/b/c` etc.
#### Proxied requests
If the `to` URL contains a remote host, local-web-server will act as a proxy - fetching and responding with the remote resource.
Mount the npm registry locally:
```sh
$ ws --rewrite '/npm/* -> http://registry.npmjs.org/$1'
```
Map local requests for repo data to the Github API:
```sh
$ ws --rewrite '/:user/repos/:name -> https://api.github.com/repos/:user/:name'
```
[Example](https://github.com/75lb/local-web-server/tree/master/example/rewrite).
### Mock Responses
Mocks give you full control over the response headers and body returned to the client. They can be used to return anything from a simple html string to a resourceful REST API. Typically, they're used to mock services but can be used for anything.
In the config, define an array called `mocks`. Each mock definition maps a [route](http://expressjs.com/guide/routing.html#route-paths) to a `response`. A simple home page:
```json
{
"mocks": [
{
"route": "/",
"response": {
"body": "Welcome to the Mock Responses example
"
}
}
]
}
```
Under the hood, the property values from the `response` object are written onto the underlying [koa response object](https://github.com/koajs/koa/blob/master/docs/api/response.md). You can set any valid koa response properies, for example [type](https://github.com/koajs/koa/blob/master/docs/api/response.md#responsetype-1):
```json
{
"mocks": [
{
"route": "/",
"response": {
"type": "text/plain",
"body": "Welcome to the Mock Responses example
"
}
}
]
}
```
#### Conditional Response
To define a conditional response, set a `request` object on the mock definition. The `request` value acts as a query - the response defined will only be returned if each property of the `request` query matches. For example, return an XML response *only* if the request headers include `accept: application/xml`, else return 404 Not Found.
```json
{
"mocks": [
{
"route": "/two",
"request": { "accepts": "xml" },
"response": {
"body": ""
}
}
]
}
```
#### Multiple Potential Responses
To specify multiple potential responses, set an array of mock definitions to the `responses` property. The first response with a matching request query will be sent. In this example, the client will get one of two responses depending on the request method:
```json
{
"mocks": [
{
"route": "/three",
"responses": [
{
"request": { "method": "GET" },
"response": {
"body": "Mock response for 'GET' request on /three
"
}
},
{
"request": { "method": "POST" },
"response": {
"status": 400,
"body": { "message": "That method is not allowed." }
}
}
]
}
]
}
```
#### Dynamic Response
The examples above all returned static data. To define a dynamic response, create a mock module. Specify its path in the `module` property:
```json
{
"mocks": [
{
"route": "/four",
"module": "/mocks/stream-self.js"
}
]
}
```
Here's what the `stream-self` module looks like. The module should export a mock definition (an object, or array of objects, each with a `response` and optional `request`). In this example, the module simply streams itself to the response but you could set `body` to *any* [valid value](https://github.com/koajs/koa/blob/master/docs/api/response.md#responsebody-1).
```js
const fs = require('fs')
module.exports = {
response: {
body: fs.createReadStream(__filename)
}
}
```
#### Response function
For more power, define the response as a function. It will receive the [koa context](https://github.com/koajs/koa/blob/master/docs/api/context.md) as its first argument. Now you have full programmatic control over the response returned.
```js
module.exports = {
response: function (ctx) {
ctx.body = 'I can do anything i want.
'
}
}
```
If the route contains tokens, their values are passed to the response. For example, with this mock...
```json
{
"mocks": [
{
"route": "/players/:id",
"module": "/mocks/players.js"
}
]
}
```
...the `id` value is passed to the `response` function. For example, a path of `/players/10?name=Lionel` would pass `10` to the response function. Additional, the value `Lionel` would be available on `ctx.query.name`:
```js
module.exports = {
response: function (ctx, id) {
ctx.body = `id: ${id}, name: ${ctx.query.name}
`
}
}
```
#### RESTful Resource example
Here's an example of a REST collection (users). We'll create two routes, one for actions on the resource collection, one for individual resource actions.
```json
{
"mocks": [
{ "route": "/users", "module": "/mocks/users.js" },
{ "route": "/users/:id", "module": "/mocks/user.js" }
]
}
```
Define a module (`users.json`) defining seed data:
```json
[
{ "id": 1, "name": "Lloyd", "age": 40, "nationality": "English" },
{ "id": 2, "name": "Mona", "age": 34, "nationality": "Palestinian" },
{ "id": 3, "name": "Francesco", "age": 24, "nationality": "Italian" }
]
```
The collection module:
```js
const users = require('./users.json')
/* responses for /users */
const mockResponses = [
/* Respond with 400 Bad Request for PUT and DELETE - inappropriate on a collection */
{ request: { method: 'PUT' }, response: { status: 400 } },
{ request: { method: 'DELETE' }, response: { status: 400 } },
{
/* for GET requests return a subset of data, optionally filtered on 'minAge' and 'nationality' */
request: { method: 'GET' },
response: function (ctx) {
ctx.body = users.filter(user => {
const meetsMinAge = (user.age || 1000) >= (Number(ctx.query.minAge) || 0)
const requiredNationality = user.nationality === (ctx.query.nationality || user.nationality)
return meetsMinAge && requiredNationality
})
}
},
{
/* for POST requests, create a new user and return the path to the new resource */
request: { method: 'POST' },
response: function (ctx) {
const newUser = ctx.request.body
users.push(newUser)
newUser.id = users.length
ctx.status = 201
ctx.response.set('Location', `/users/${newUser.id}`)
}
}
]
module.exports = mockResponses
```
The individual resource module:
```js
const users = require('./users.json')
/* responses for /users/:id */
const mockResponses = [
/* don't support POST here */
{ request: { method: 'POST' }, response: { status: 400 } },
/* for GET requests, return a particular user */
{
request: { method: 'GET' },
response: function (ctx, id) {
ctx.body = users.find(user => user.id === Number(id))
}
},
/* for PUT requests, update the record */
{
request: { method: 'PUT' },
response: function (ctx, id) {
const updatedUser = ctx.request.body
const existingUserIndex = users.findIndex(user => user.id === Number(id))
users.splice(existingUserIndex, 1, updatedUser)
ctx.status = 200
}
},
/* DELETE request: remove the record */
{
request: { method: 'DELETE' },
response: function (ctx, id) {
const existingUserIndex = users.findIndex(user => user.id === Number(id))
users.splice(existingUserIndex, 1)
ctx.status = 200
}
}
]
module.exports = mockResponses
```
[Example](https://github.com/75lb/local-web-server/tree/master/example/mock).
### HTTPS Server
Some modern techs (ServiceWorker, any `MediaDevices.getUserMedia()` request etc.) *must* be served from a secure origin (HTTPS). To launch an HTTPS server, supply a `--key` and `--cert` to local-web-server, for example:
```
$ ws --key localhost.key --cert localhost.crt
```
If you don't have a key and certificate it's trivial to create them. You do not need third-party verification (Verisign etc.) for development purposes. To get the green padlock in the browser, the certificate..
* must have a `Common Name` value matching the FQDN of the server
* must be verified by a Certificate Authority (but we can overrule this - see below)
First create a certificate:
1. Install openssl.
`$ brew install openssl`
2. Generate a RSA private key.
`$ openssl genrsa -des3 -passout pass:x -out ws.pass.key 2048`
3. Create RSA key.
```
$ openssl rsa -passin pass:x -in ws.pass.key -out ws.key
```
4. Create certificate request. The command below will ask a series of questions about the certificate owner. The most imporant answer to give is for `Common Name`, you can accept the default values for the others. **Important**: you **must** input your server's correct FQDN (`dev-server.local`, `laptop.home` etc.) into the `Common Name` field. The cert is only valid for the domain specified here. You can find out your computers host name by running the command `hostname`. For example, mine is `mba3.home`.
`$ openssl req -new -key ws.key -out ws.csr`
5. Generate self-signed certificate.
`$ openssl x509 -req -days 365 -in ws.csr -signkey ws.key -out ws.crt`
6. Clean up files we're finished with
`$ rm ws.pass.key ws.csr`
7. Launch HTTPS server. In iTerm, control-click the first URL (with the hostname matching `Common Name`) to launch your browser.
```
$ ws --key ws.key --cert ws.crt
serving at https://mba3.home:8010, https://127.0.0.1:8010, https://192.168.1.203:8010
```
Chrome and Firefox will still complain your certificate has not been verified by a Certificate Authority. Firefox will offer you an `Add an exception` option, allowing you to ignore the warning and manually mark the certificate as trusted. In Chrome on Mac, you can manually trust the certificate another way:
1. Open Keychain
2. Click File -> Import. Select the `.crt` file you created.
3. In the `Certificates` category, double-click the cert you imported.
4. In the `trust` section, underneath `when using this certificate`, select `Always Trust`.
Now you have a valid, trusted certificate for development.
#### Built-in certificate
As a quick win, you can run `ws` with the `https` flag. This will launch an HTTPS server using a [built-in certificate](https://github.com/75lb/local-web-server/tree/master/ssl) registered to the domain 127.0.0.1.
### Stored config
Use the same options every time? Persist then to `package.json`:
```json
{
"name": "example",
"version": "1.0.0",
"local-web-server": {
"port": 8100,
"forbid": "*.json"
}
}
```
or `.local-web-server.json`
```json
{
"port": 8100,
"forbid": "*.json"
}
```
local-web-server will merge and use all config found, searching from the current directory upward. In the case both `package.json` and `.local-web-server.json` config is found in the same directory, `.local-web-server.json` will take precedence. Options set on the command line take precedence over all.
To inspect stored config, run:
```sh
$ ws --config
```
### Logging
By default, local-web-server outputs a simple, dynamic statistics view. To see traditional web server logs, use `--log-format`:
```sh
$ ws --log-format combined
serving at http://localhost:8000
::1 - - [16/Nov/2015:11:16:52 +0000] "GET / HTTP/1.1" 200 12290 "-" "Mozilla/5.0 (Macintosh; Intel Mac OS X 10_11_1) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/48.0.2562.0 Safari/537.36"
```
The format value supplied is passed directly to [morgan](https://github.com/expressjs/morgan). The exception is `--log-format none` which disables all output.
### Access Control
By default, access to all files is allowed (including dot files). Use `--forbid` to establish a blacklist:
```sh
$ ws --forbid '*.json' '*.yml'
serving at http://localhost:8000
```
[Example](https://github.com/75lb/local-web-server/tree/master/example/forbid).
### Other usage
#### Debugging
Prints information about loaded middleware, arguments, remote proxy fetches etc.
```sh
$ ws --verbose
```
#### Compression
Serve gzip-compressed resources, where applicable
```sh
$ ws --compress
```
#### Disable caching
Disable etag response headers, forcing resources to be served in full every time.
```sh
$ ws --no-cache
```
#### mime-types
You can set additional mime-type/extension mappings, or override the defaults by setting a `mime` value in the stored config. This value is passed directly to [mime.define()](https://github.com/broofa/node-mime#mimedefine). Example:
```json
{
"mime": {
"text/plain": [ "php", "pl" ]
}
}
```
[Example](https://github.com/75lb/local-web-server/tree/master/example/mime-override).
#### Log Visualisation
Instructions for how to visualise log output using goaccess, logstalgia or gltail [here](https://github.com/75lb/local-web-server/blob/master/doc/visualisation.md).
## Install
Ensure [node.js](http://nodejs.org) is installed first. Linux/Mac users may need to run the following commands with `sudo`.
```sh
$ npm install -g local-web-server
```
This will install the `ws` tool globally. To see the available options, run:
```sh
$ ws --help
```
## Distribute with your project
The standard convention with client-server applications is to add an `npm start` command to launch the server component.
1\. Install the server as a dev dependency
```sh
$ npm install local-web-server --save-dev
```
2\. Add a `start` command to your `package.json`:
```json
{
"name": "example",
"version": "1.0.0",
"local-web-server": {
"port": 8100,
"forbid": "*.json"
},
"scripts": {
"start": "ws"
}
}
```
3\. Document how to build and launch your site
```sh
$ npm install
$ npm start
serving at http://localhost:8100
```
## API Reference
* [local-web-server](#module_local-web-server)
* [localWebServer([options])](#exp_module_local-web-server--localWebServer) ⇒ [KoaApplication](https://github.com/koajs/koa/blob/master/docs/api/index.md#application) ⏏
* [~rewriteRule](#module_local-web-server--localWebServer..rewriteRule)
### localWebServer([options]) ⇒ [KoaApplication](https://github.com/koajs/koa/blob/master/docs/api/index.md#application) ⏏
Returns a Koa application you can launch or mix into an existing app.
**Kind**: Exported function
**Params**
- [options] object - options
- [.static] object - koa-static config
- [.root] string = "." - root directory
- [.options] string - [options](https://github.com/koajs/static#options)
- [.serveIndex] object - koa-serve-index config
- [.path] string = "." - root directory
- [.options] string - [options](https://github.com/expressjs/serve-index#options)
- [.forbid] Array.<string> - A list of forbidden routes, each route being an [express route-path](http://expressjs.com/guide/routing.html#route-paths).
- [.spa] string - specify an SPA file to catch requests for everything but static assets.
- [.log] object - [morgan](https://github.com/expressjs/morgan) config
- [.format] string - [log format](https://github.com/expressjs/morgan#predefined-formats)
- [.options] object - [options](https://github.com/expressjs/morgan#options)
- [.compress] boolean - Serve gzip-compressed resources, where applicable
- [.mime] object - A list of mime-type overrides, passed directly to [mime.define()](https://github.com/broofa/node-mime#mimedefine)
- [.rewrite] [Array.<rewriteRule>](#module_local-web-server--localWebServer..rewriteRule) - One or more rewrite rules
- [.verbose] boolean - Print detailed output, useful for debugging
**Example**
```js
const localWebServer = require('local-web-server')
localWebServer().listen(8000)
```
#### localWebServer~rewriteRule
The `from` and `to` routes are specified using [express route-paths](http://expressjs.com/guide/routing.html#route-paths)
**Kind**: inner typedef of [localWebServer](#exp_module_local-web-server--localWebServer)
**Properties**
| Name | Type | Description |
| --- | --- | --- |
| from | string | request route |
| to | string | target route |
**Example**
```json
{
"rewrite": [
{ "from": "/css/*", "to": "/build/styles/$1" },
{ "from": "/npm/*", "to": "http://registry.npmjs.org/$1" },
{ "from": "/:user/repos/:name", "to": "https://api.github.com/repos/:user/:name" }
]
}
```
* * *
© 2013-16 Lloyd Brookes <75pound@gmail.com>. Documented by [jsdoc-to-markdown](https://github.com/jsdoc2md/jsdoc-to-markdown).