Webpack Entry, Output, and Mode Essentials Quiz Quiz

Challenge your understanding of essential Webpack settings like entry points, output configuration, and mode options. This quiz helps clarify key Webpack concepts for managing bundles and optimizing builds in modern web development workflows.

1. Understanding the 'entry' Property

   Which statement best describes the main purpose of the 'entry' property in a typical Webpack configuration?

   1. It sets the port number for the development server.
   2. It specifies the starting point for building the dependency graph.
   3. It determines the file extension for bundled output.
   4. It defines how JavaScript files are transpiled.

   Explanation: The 'entry' property tells Webpack where to start its module bundling process by pointing to the main file or files of your application. It does not control file transpilation, which is handled by loaders, making option B incorrect. The file extension for the bundled output is defined in the 'output' section, so option C does not describe 'entry'. Option D relates to development server configuration, not the entry point.

2. Configuring 'output.filename'

   If you want your output files to include a hash for cache busting, which 'output.filename' pattern should you use in Webpack?

   1. 'hash.bundle.js'
   2. 'bundle.js.hash'
   3. 'bundle.[hash].js'
   4. 'bundle.hash.js'

   Explanation: Using 'bundle.[hash].js' adds a unique build hash to the output filename, which is useful for cache management. The [hash] placeholder is recognized by Webpack, while the other options, such as 'bundle.hash.js' and 'bundle.js.hash', will not dynamically insert the current build hash. 'hash.bundle.js' simply creates a file named literally as such, without including a variable hash.

3. Default Output Directory

   What is the default directory for Webpack's output files when you do not specifically set the 'output.path' property?

   1. The directory containing your source files
   2. The 'dist' folder in your project root
   3. A temporary folder created at runtime
   4. The 'public' folder in your project

   Explanation: Webpack uses 'dist' in the project root as the default output directory when 'output.path' is not specified. Option B ('public') is commonly used in other contexts but not as the default for Webpack's output. The directory with source files (option C) is not used by default for output, and option D is incorrect as Webpack does not create a temporary folder by default.

4. Selecting the Proper Mode

   Which 'mode' value should you set in Webpack for optimized production bundles with minification enabled?

   1. 'develop'
   2. 'production'
   3. 'build'
   4. 'test'

   Explanation: Setting 'mode' to 'production' in Webpack enables optimizations such as minification and scope hoisting for smaller, faster bundles. The values 'develop', 'build', and 'test' are not valid recognized Webpack modes. 'development' is a valid alternative, but it does not enable production-oriented optimizations like 'production' does.

5. Using Multiple Entry Points

   How does Webpack handle multiple entry points when they are defined as an object with different keys in the configuration?

   1. It throws an error and stops the build process.
   2. It merges all entry points into a single bundle file.
   3. It creates separate output bundles for each entry point.
   4. It only processes the first entry and ignores the rest.

   Explanation: When multiple entry points are defined as an object, Webpack creates a separate output bundle for each key. Option B is incorrect because merging occurs only when entries are combined into a single entry array. Option C is not true; Webpack processes all provided entries. Option D is incorrect, as this configuration is valid and does not cause errors.