analyze-module-size

Analyze the size of your module dependencies

analyze-module-size shows you, why your package is so large. The reason for the size of your package often lies in the dependencies you are using. For example request@2.81.0` is 7080kb large (including its 53 dependencies) and it comes with a lot of libraries that you may not even need. If you are aware of that, you may choose to use a different library (e.g. popsicle).

The module cost-of-modules does the same, but it only shows one level of the dependency tree. It was an inspiration, but I took no code from it.

Finally, this program still has a lot of opportunities for enhancement. If you have wishes, ideas or questions, please open an issue.

Installation

npm install -g analyze-module-size

Usage

Run analyze-module-size in your project directory. The output will be something like this: (Note that the displayed sizes are accumulated from the each module an its dependencies):

size: 68k... with-dependencies: 1204k
├─┬ [email protected], 488k, 17 deps
│ ├─┬ [email protected], 344k, 10 deps
│ │ ├─┬ [email protected], 136k, 3 deps
│ │ │ └─┬ [email protected], 88k, 2 deps
│ │ │   ├── [email protected], 40k, 0 deps
│ │ │   └── [email protected], 24k, 0 deps
│ │ ├─┬ [email protected], 60k, 2 deps
│ │ │ ├─┬ [email protected], 40k, 1 deps
│ │ │ │ └── [email protected], 20k, 0 deps
│ │ │ └── [email protected], 20k, 0 deps
│ │ ├─┬ [email protected], 40k, 1 deps
│ │ │ └── [email protected], 20k, 0 deps
│ │ ├── [email protected], 32k, 0 deps
│ │ ├── [email protected], 24k, 0 deps
│ │ └── [email protected], 20k, 0 deps
│ ├─┬ [email protected], 44k, 1 deps
│ │ └── [email protected], 24k, 0 deps
│ ├─┬ [email protected], 40k, 1 deps
│ │ └── [email protected], 20k, 0 deps
│ ├── [email protected], 20k, 0 deps
│ └── [email protected], 20k, 0 deps
├─┬ [email protected], 344k, 10 deps
│ ├─┬ [email protected], 136k, 3 deps
│ │ └─┬ [email protected], 88k, 2 deps
│ │   ├── [email protected], 40k, 0 deps
│ │   └── [email protected], 24k, 0 deps
│ ├─┬ [email protected], 60k, 2 deps
│ │ ├─┬ [email protected], 40k, 1 deps
│ │ │ └── [email protected], 20k, 0 deps
│ │ └── [email protected], 20k, 0 deps
│ ├─┬ [email protected], 40k, 1 deps
│ │ └── [email protected], 20k, 0 deps
│ ├── [email protected], 32k, 0 deps
│ ├── [email protected], 24k, 0 deps
│ └── [email protected], 20k, 0 deps
├─┬ [email protected], 144k, 6 deps
│ ├─┬ [email protected], 40k, 1 deps
│ │ └── [email protected], 20k, 0 deps
│ ├─┬ [email protected], 40k, 1 deps
│ │ └── [email protected], 20k, 0 deps
│ ├── [email protected], 20k, 0 deps
│ ├── [email protected], 20k, 0 deps
│ └── [email protected], 20k, 0 deps
├─┬ [email protected], 132k, 1 deps
│ └── [email protected], 20k, 0 deps
├── [email protected], 88k, 0 deps
├── [email protected], 76k, 0 deps
├── [email protected], 52k, 0 deps
├── [email protected], 48k, 0 deps
├─┬ [email protected], 44k, 1 deps
│ └── [email protected], 20k, 0 deps
├── [email protected], 44k, 0 deps
├── [email protected], 20k, 0 deps
└── [email protected], 20k, 0 deps

CLI options

Usage: analyze-module-size [options]

  Analyzes the size of the package in the current directories, including the size of (production) dependencies

  Options:

    -V, --version         output the version number
    -d, --depth <levels>  Show only dependencies up to a given depth of recursion
    -h, --help            output usage information

How it works

`` collects all modules from the node_modules directory, the node_modules directory of each of those modules and the node_modules directory in that modules, and so on.

When all packages have been collected, it reads the package.json of each module and uses the _location-property and the _requiredBy-property to recreate the complete dependency tree.

• _location contains the location of the module in the directory tree. A module in node_modules/packageA/node_modules/packageB has the location /packageA/packageB
• _requiredBy contains a list of module that are dependent on the current module. For each such module, it contains the value of the _location-property.

Once the packages is connected, the stats for each package are computed:

• The number of dependencies is computed transitively across the tree.
• The total kilobytes (1024 bytes) is computed, include all dependencies. The computation of file sizes assumes that only whole blocks are used, even by small files. The blksize-property of the fs.Stats-object is used as block size. If this value is missing (e.g. on Windows), a size of 4096 is used.

Caveats

In some cases, the dependencies in the node_modules-directory are tempered with. For example, lerna combines dependencies of multiple packages in the node_modules-directory of the root-project and removes obsolete dependencies from the tree. This can lead to cycles in the dependency tree which are displayed in the output like this:

size: 42k... with-dependencies: 42k
└─┬ [email protected], 42k, 3 deps
  └─┬ [email protected], 42k, 3 deps
    └─┬ [email protected], 42k, 3 deps
      └── [email protected] (cycle detected)

Furthermore, this and the use of optional dependencies can lead to a situation where a package is _requiredBy an existing dependency (i.e. a dependent package) but does not exist anymore in the tree. For those delete packages, a dummy package is displayed in a separate tree.

size: 42k... with-dependencies: 42k
└── [email protected], 42k, 0 deps

missing packages, that are referenced as dependent of an existing dependency
└─┬ /dep3, 42k, 2 deps
  └─┬ [email protected], 42k, 1 deps
    └── [email protected], 42k, 0 deps

In this example, a module [email protected] was found. The _requireBy-property shows that dep2 is part of the tree, because it is a dependency of a module that should be in node_modules/dep3, which could not be found.

License

analyze-module-size is published under the MIT-license.

See LICENSE.md for details.

Release-Notes

For release notes, see CHANGELOG.md

Contributing guidelines

See CONTRIBUTING.md.