Author and E-Mail Check (AM-C)

Description

This tool compares the Git author and e-mail address of the latest commit, against a custom whitelist.

If it found a match, it prints a success message to stdout.
Else, it prints an error message to stderr and terminates with an exit code 1.

If you don't want to expose E-Mail addresses into a file in your repo, you can also use secret variables from your CI-Tool.
See the section Arguments: -s, --secret (optional)

Warning

This tool isn't meant for OpSec, only for an additional quality gate.

Usage

File Format

The file encoding must be UTF-8.

With the whitelist.amc file, you can define which authors should be verified. The syntax for an entry is:

<author name> <email>
             ^ white space in between

It doesn't matter if the author name (configured in Git) has multiple whitespaces. The script fetches the information via --pretty=format:%an %ae.

Multiple entries are possible and have to be delimited by a newline:

somefirstname somelastname foo@domain.com
somenickname nick@domain.com

You can invalidate single entries, by prepending a # symbol:

name lastname name@domain.com       <- Not ignored
# name lastname name@domain.com     <- Ignored
- name lastname name@domain.com     <- Ignored

Basically you can use any symbol, but if you use something like: ignore name lastname name@domain.com and a coworker has this same exact name configured, it would result in false-positives.

CI-Integration

In GitHub, you can integrate it in your *.yml file with:

    - name: Author and E-Mail check
      run: |
        python anypath/am-c/amc.py -p whitelist.amc

Arguments

-p, --path <Path> (optional)

You can pass a custom path to the whitelist.amc. Just invoke the script with:

python amc.py -p path/path/whitelist.amc

-s, --secret (optional)

If you don't want to expose your E-Mail addresses to webcrawlers, you can store the data inside a secret variable from your CI environment. (See "Using Secrets in GitHub Actions" for more information)

You have to set up a new secret variable, named WHITELIST_AMC. The content of the variable follows the same formatting rules, like in the section File Format.
After that, modify your entry in the *.yml file and expose the variable to the environment:

    - name: Author and E-Mail check
      env:
        WHITELIST_AMC: ${{ secrets.WHITELIST_AMC }}
      run: |
        python amc.py -s

Changing File Name / Env Variable Name

Currently, I leave those both names hard coded, because I don't expect, that they have to be altered that much.
But if the demand rises, I'm going to implement a config file.

Change file name: whitelist.amc

Head to:

amc.py
    |- class: FilePaths
        |- self.whitelist_file: pathlib.Path = self.conv_path('whitelist.amc')

Change the string whitelist.amc to your needs.

Change env variable name: WHITELIST_AMC

Head to:

amc.py
    |- class: FetchSecretEnvVariable
        |- self.whitelist_env: str = 'WHITELIST_AMC'

Change the string WHITELIST_AMC to your needs.