Buck: http_archive()
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This is liable to change in the future.

An http_archive() rule is used to download and extract archives from the Internet to be used as dependencies for other rules. These rules are downloaded by running buck fetch, or can be downloaded as part ofbuck build by setting [download].in_build


  • name (required) #

    The short name for this build target. This is also used for the name of the file on disk if  out  is not provided.

  • urls (required) #

    A list of urls to attempt to download from. They are tried in order, and subsequent ones are only tried if the download fails. If validation fails, a new URL is not used. Supported protocols are "http", "https", and "mvn".

  • sha256 (required) #

    The SHA-256 hash of the downloaded artifact. Buck verifies this is correct and fails the fetch command if it doesn't match in order to guarantee repeatable builds.

  • out (defaults to None) #

    An optional name to call the directory that the downloaded artifact is extracted into. Buck will generate a default name if one is not provided that uses the name of the rule.

  • strip_prefix (defaults to None) #

    If set, files under this path will be extracted to the root of the output directory. Siblings or cousins to this prefix will not be extracted at all.

    For example, if a tarball has the layout:

    • foo/bar/bar-0.1.2/data.dat
    • foo/baz/baz-0.2.3
    • foo_prime/bar-0.1.2
    Only data.dat will be extracted, and it will be extracted into the output directory specified in out.

  • type (defaults to None) #

    Normally, archive type is determined by the file's extension. If type is set, then autodetection is overriden, and the specified type is used instead.

    Supported values are: zip, tar, tar.gz,tar.bz2, tar.xz, and tar.zst.

  • visibility (defaults to []) #

    List of build target patterns that identify the build rules that can include this rule as a dependency, for example, by listing it in their deps or exported_deps attributes. For more information, see visibility.

  • licenses (defaults to []) #

    Set of license files for this library. To get the list of license files for a given build rule and all of its dependencies, you can use buck query.

  • labels (defaults to []) #

    Set of arbitrary strings which allow you to annotate a build rule with tags that can be searched for over an entire dependency tree using buck query attrfilter().


Using http_archive(), third party packages can be downloaded from an https URL and used in other library types.

  name = 'thrift-archive',
  urls = [
  sha256 = '7baa80df284117e5b945b19b98d367a85ea7b7801bd358ff657946c3bd1b6596',

  name = 'thrift-compiler-bin',
  out = 'thrift',
  cmd = 'cp $(location :thrift-archive)/bin/thrift $OUT',

  cmd="$(exe :thrift-compiler-bin) --gen cpp2 -o $OUT $(location //:thrift-file)",