The pub tool

The pub tool has commands for managing packagesand for deploying packages and command-line apps.For general information about using the pub package manager, seeHow to use packages.

Flutter note: If you’re using the Flutter SDK, don’t use the pub command directly. Instead use the flutter pub command, as described in Using packages on the Flutter website.

Quick links to the pub commands:

• pub cache
• pub deps
• pub downgrade
• pub get
• pub global
• pub publish
• pub run
• pub upgrade
• pub uploader

_Problems?_See Troubleshooting Pub.

Pub’s commands fall into the following categories:

• Managing package dependencies
• Running command-line apps
• Deploying packages and apps

Managing package dependencies

Pub provides a number of commands for managing thepackages your code depends on.

In this group, the most commonly used commands are pub get andpub upgrade, which retrieve or upgrade dependencies used by a package.Every time you modify a pubspec file, run pub getto make sure the dependencies are up to date. Some IDEsperform this step automatically on the creation of a project,or any modification of the pubspec.

• pub cache
• Manages pub’s local package cache. Use this command to add packagesto your cache, or to perform a clean reinstall of all packages inyour cache.
• pub deps
• Lists all dependencies used by the current package.
• pub downgrade
• Retrieves the lowest versions of all the packages that arelisted as dependencies used by the current package. Used for testingthe lower range of your package’s dependencies.
• pub get
• Retrieves the packages that are listed as the dependencies forthe current package.If a pubspec.lock file already exists, fetches the versionof each dependency (if possible) as listed in the lock file.Creates or updates the lock file, as needed.
• pub upgrade
• Retrieves the latest version of each package listedas dependencies used by the current package. If a pubspec.lockfile exists, ignores the versions listed in the lock file and fetchesthe newest versions that honor the constraints in the pubspec.Creates or updates the lock file, as needed.

Running command-line apps

Two commands let you run Dart scripts from the command line:

• The pub run command invokes a Dart script in yourpackage, or in one of its dependencies.

• The pub global command lets you work withglobally available packages.

Deploying packages and apps

With pub you can publish packages and command-line apps.

Note: Pub used to support building apps through commands like pub build and pub serve. That functionality is now in other tools such as the build system. For details, see Obsolete Pub Features.

Packages

To share your Dart packages with the world, you canuse the pub publish command to upload thepackage to the pub.dev site. Thepub uploader command enables specificusers to modify and upload new versions of your package.

Command-line apps

For any package that contains scripts (anything under the bin/directory), consider adding the executables tag to the pubspec file.When a script is listed under executables, users can runpub global activateto make it directly available from the command line.

Global options

Several command-line options work with all of the pub commands.These include:

• —help or -h
• Print usage information.
• —version
• Print version of pub.
• —trace
• Print debugging information when an error occurs.
• —verbosity=<level>
• The specified level determines the amount of information that is displayed:

• • all
  • Show all output, including internal tracing messages.
• • io
  • Show I/O operations.
• • normal
  • Show errors, warnings, and user messages.
• • solver
  • Show steps during version resolution.

• -verbose or -v
• Equivalent to —verbosity=all.