Metadater

A Python package providing an easy way to get a Windows app's version and other metadata from Git during development or from the executable after freezing.

https://github.com/hylkepostma/metadater

When building a portable executable (for example using PyInstaller) we add metadata like the app's name and version. Most of this metadata is already available when using Git. Think for example of version numbering in Git tags and the author's name in the Git user.name setting.

Metadater provides an easy way to get this metadata from Git and to use it in your application during development. When you inject these metadata fields to your executable after the freezing process (for example using Verpatch) you can also retrieve this metadata after freezing your application using the same methods. See also the mapping below.

Prerequisites

• Your project has a Git repository
• Your repository has at least one commit
• Your repository has at least one tag following the SemVer specification
• There is a Git user.name and user.email configured

Installation

Using pip:

pip install metadater

Usage

To get a specific metadata field:

from metadater import MetaDater
metadata = MetaDater().metadata
print(metadata.version)

1.2.3

print(metadata.author)

John Doe

To get all metadata fields:

from metadater import MetaDater
metadata = MetaDater().get()
for field in metadata:
    print(field, metadata[field])

author John Doe
build 0-g1d1757c-dirty
copyright John Doe, 2020
description Lorem ipsum this app dolor sit amet
email john@example.com
file_version 2.0.5.0
name Metadater
prerelease rc.1
product_version 2.0.5-rc.1+0-g1d1757c-dirty
repo metadater
semver 2.0.5-rc.1+0-g1d1757c-dirty
version 2.0.5
version_prerelease 2.0.5-rc.1
version_info 2.0.5-rc.1+0-g1d1757c-dirty

API

class MetaDater

• metadata contains the MetaData object
• get() returns a dictionary with all the attributes of the MetaData object

class MetaData

• repo
• name
• description
• author
• email is only available in unfrozen state
• copyright
• semver
• version_info contains a VersionInfo object (more info)
• version
• prerelease
• build
• file_version
• product_version
• version_prerelease

Override using metadata.json file

You can override the Git values using an metadata.json file in your repository's root. The file should contain the fields (and values) you want to override (or add), like so:

{
    "author": "John Doe",
    "license": "MIT",
    "foo": "bar"
}

Please note that newly added values (like license and foo) are only available in unfrozen state because they lack a mapping with the PE header.

Mapping

Metadater uses a Python package called pefile for finding metadata in the PE headers and makes it available using the following mapping:

Acknowledgements

• https://github.com/erocarrera/pefile
• https://github.com/pallets/click
• https://github.com/python-semver/python-semver/