Publishing a Package

Pub isn’t just for using other people’s packages. It also allows you to share your packages with the world. If you have a useful project and you want others to be able to use it, use the pub publish command.

Preparing to publish

When publishing a package, it’s important to follow the pubspec format and package layout conventions. Some of these are required in order for others to be able to use your package. Others are suggestions to help make it easier for users to understand and work with your package. In both cases, pub tries to help you by pointing out what changes will help make your package play nicer with the Dart ecosystem. There are a few additional requirements for uploading a package:

  • You must include a license file (named LICENSE, COPYING, or some variation) that contains an open-source license. We recommend the BSD license, which is used by Dart itself. You must also have the legal right to redistribute anything that you upload as part of your package.

  • Your package must be less than 10 MB large after gzip compression. If it’s too large, consider splitting it into multiple packages, or cutting down on the number of included resources or examples.

  • Your package should only have hosted dependencies. Git dependencies are allowed but strongly discouraged; not everyone using Dart has Git installed, and Git dependencies don’t support version resolution as well as hosted dependencies do.

Be aware that the email address associated with your Google account is displayed on the Pub site along with any packages you upload.

Important files

Pub uses the contents of a few files to create a page for your package at <package site>/packages/<your_package>. Here are the files that affect how your package’s page looks:

  • README: The README file (README, README.md, README.mdown, README.markdown) is the main content featured in your package’s page.
  • CHANGELOG: Your package’s CHANGELOG (CHANGELOG, CHANGELOG.md, CHANGELOG.mdown, CHANGELOG.markdown), if found, will also be featured in a tab on your package’s page, so that developers can read it right from the Pub site.
  • The pubspec: Your package’s pubspec.yaml file is used to fill out details about your package on the right side of your package’s page, like its description, authors, etc.

Publishing your package

For your first time around, you can perform a dry run:

$ pub publish --dry-run

Pub will check to make sure that your package follows the pubspec format and package layout conventions, and then upload your package to the Pub site. Pub will also show you all of the files it intends to publish. Here’s an example of publishing a package named transmogrify:

Publishing transmogrify 1.0.0
    .gitignore
    CHANGELOG.md
    README.md
    lib
        transmogrify.dart
        src
            transmogrifier.dart
            transmogrification.dart
    pubspec.yaml
    test
        transmogrify_test.dart

Package has 0 warnings.

When you’re ready to publish your package, remove the --dry-run argument:

$ pub publish

After your package has been successfully uploaded to Pub site, any pub user will be able to download it or depend on it in their projects. For example, if you just published version 1.0.0 of your transmogrify package, then another Dart developer can add it as a dependency in their pubspec.yaml:

dependencies:
  transmogrify: ^1.0.0

What files are published?

All files in your package are included in the published package, with the following exceptions:

  • Any packages directories.
  • Your package’s lockfile.
  • If you aren’t using Git, all hidden files (that is, files whose names begin with .).
  • If you’re using Git, any files ignored by your .gitignore file.

Be sure to delete any files you don’t want to include (or add them to .gitignore). pub publish lists all files that it’s going to publish before uploading your package, so examine the list carefully before completing your upload.

Authors versus uploaders

The package authors as listed in the pubspec.yaml file are different from the list of people authorized to publish that package. Whoever publishes the first version of some package automatically becomes the first and only person authorized to upload additional versions of the package. To allow or disallow other people to upload versions, use the pub uploader command.

Publishing is forever

Keep in mind that publishing is forever. As soon as you publish your package, users will be able to depend on it. Once they start doing that, removing the package would break theirs. To avoid that, pub strongly discourages deleting packages. You can always upload new versions of your package, but old ones will continue to be available for users that aren’t ready to upgrade yet.

Resources

For more information, see the reference pages for: