The entry object is where webpack looks to start building the bundle. The context is an absolute string to the directory that contains the entry files.

context

string

The base directory, an absolute path, for resolving entry points and loaders from configuration.

module.exports = {
  //...
  context: path.resolve(__dirname, 'app')
};

By default the current directory is used, but it's recommended to pass a value in your configuration. This makes your configuration independent from CWD (current working directory).

entry

string [string] object = { <key> string | [string] } (function() => string | [string] | object = { <key> string | [string] })

The point or points where to start the application bundling process. If an array is passed then all items will be processed.

A dynamically loaded module is not an entry point.

Simple rule: one entry point per HTML page. SPA: one entry point, MPA: multiple entry points.

module.exports = {
  //...
  entry: {
    home: './home.js',
    about: './about.js',
    contact: './contact.js'
  }
};

Naming

If a string or array of strings is passed, the chunk is named main. If an object is passed, each key is the name of a chunk, and the value describes the entry point for the chunk.

Dynamic entry

If a function is passed then it will be invoked on every make event.

Note that the make event triggers when webpack starts and for every invalidation when watching for file changes.

module.exports = {
  //...
  entry: () => './demo'
};

or

module.exports = {
  //...
  entry: () => new Promise((resolve) => resolve(['./demo', './demo2']))
};

For example: you can use dynamic entries to get the actual entries from an external source (remote server, file system content or database):

webpack.config.js

module.exports = {
  entry() {
    return fetchPathsFromSomeExternalSource(); // returns a promise that will be resolved with something like ['src/main-layout.js', 'src/admin-layout.js']
  }
};

When combining with the output.library option: If an array is passed only the last item is exported.