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The PEX (Python EXecutable) tool (https://github.com/pantsbuild/pex).

Config section: [download-pex-bin]

Basic options


Advanced options


default: v2.1.54

Use this version of pex.

Supported pex versions: >=2.1.51,<3.0


--download-pex-bin-known-versions="['<str>', '<str>', ...]"

Known versions to verify downloads against.

Each element is a pipe-separated string of version|platform|sha256|length, where:

  • version is the version string
  • platform is one of [linux_arm64,linux_x86_64,macos_arm64,macos_x86_64],
  • sha256 is the 64-character hex representation of the expected sha256
    digest of the download file, as emitted by shasum -a 256
  • length is the expected length of the download file in bytes, as emmitted by
    wc -c

E.g., 3.1.2|macos_x86_64|6d0f18cd84b918c7b3edd0203e75569e0c7caecb1367bbbe409b44e28514f5be|42813.

Values are space-stripped, so pipes can be indented for readability if necessary.


one of: error, warning
default: error

What action to take in case the requested version of pex is not supported.

Supported pex versions: >=2.1.51,<3.0


default: https://github.com/pantsbuild/pex/releases/download/{version}/pex

URL to download the tool, either as a single binary file or a compressed file (e.g. zip file). You can change this to point to your own hosted file, e.g. to work with proxies or for access via the filesystem through a file:$abspath URL (e.g. file:/this/is/absolute, possibly by templating the buildroot in a config file).

Use {version} to have the value from --version substituted, and {platform} to have a value from --url-platform-mapping substituted in, depending on the current platform. For example, https://github.com/.../protoc-{version}-{platform}.zip.


--download-pex-bin-url-platform-mapping="{'key1': val1, 'key2': val2, ...}"
default: {}

A dictionary mapping platforms to strings to be used when generating the URL to download the tool.

In --url-template, anytime the {platform} string is used, Pants will determine the current platform, and substitute {platform} with the respective value from your dictionary.

For example, if you define {"macos_x86_64": "apple-darwin", "linux_x86_64": "unknown-linux"}, and run Pants on Linux with an intel architecture, then {platform}` will be substituted in the --url-template option with unknown-linux.

Deprecated options