[#2] Clean code: extract functions

Author: josecelano

src/03_sign_commit_using_the_gitpython_package.py

@@ -21,17 +21,64 @@ def git_init(temp_dir):
     return repo
 
 
-def execute_console_command(command):
-    print(f'Executing command: {command}')
+def execute_console_command(command, show_ouput=False):
     output = os.popen(command).read()
-    print(output)
+    if (show_ouput):
+        print(output)
 
 
-def main(gpg_private_key, passphrase):
-    temp_dir = create_temp_dir()
+def import_gpg_private_key(gpg_private_key, passphrase):
+    """
+    Import PGP key into the the local keyring
+    """
+    gpg = gnupg.GPG(gnupghome='/root/.gnupg', verbose=False, use_agent=True)
+    gpg.import_keys(gpg_private_key, passphrase=passphrase)
+
+
+def preset_passphrase(keygrip, passphrase):
+    """
+    Preset passphrase using gpg-connect-agent in order to avoid prompting the user for it.
+    """
+    hex_passphrase = passphrase.encode('utf-8').hex().upper()
+    preset_passphrase_command = f'gpg-connect-agent \'PRESET_PASSPHRASE {keygrip} -1 {hex_passphrase}\' /bye'
+    execute_console_command(preset_passphrase_command)
+
+
+def set_git_glogal_user_config(repo):
+    """
+    This configuration prevents from having this git error:
+
+    stderr: 'Committer identity unknown
+
+    *** Please tell me who you are.
+
+    Run
+
+    git config --global user.email "you@example.com"
+    git config --global user.name "Your Name"
+
+    to set your account's default identity.
+    Omit --global to set the identity only in this repository.
+
+    fatal: unable to auto-detect email address (got 'root@b37fb619ac5a.(none)')'
+    """
+    repo.config_writer().set_value("user", "name", "A committer").release()
+    repo.config_writer().set_value("user", "email", "committer@example.com").release()
+
+
+def set_gpg_configuration(gpg_private_key, passphrase, keygrip):
+    import_gpg_private_key(gpg_private_key, passphrase)
+    preset_passphrase(keygrip, passphrase)
+
+
+def create_signed_commit(temp_dir, signingkey):
+    # Initialize the Git repo
     repo = git_init(temp_dir)
 
-    # Create file
+    # Git config
+    set_git_glogal_user_config(repo)
+
+    # Create new file to commit
     filename = "README_SIGNED.md"
     file_path = temp_dir + '/' + filename
     print(f'Creating file: {file_path}')
@@ -42,33 +89,26 @@ def main(gpg_private_key, passphrase):
     index = repo.index
     index.add([file_path])
 
-    # Needed for commit with signature:
+    # Write index. Needed for commit with signature:
     # https://github.com/gitpython-developers/GitPython/issues/580#issuecomment-282474086
     index.write()
 
-    # TODO: get from console, gnupg package or env var
-    signingkey = '27304EDD6079B81C'
-    # Of master key 88966A5B8C01BD04F3DA440427304EDD6079B81C
-    keygrip = '449972AC9FF11BCABEED8A7AE834C4349CC4DBFF'
-    hex_passphrase = passphrase.encode('utf-8').hex().upper()
+    # Signed commit
+    repo.git.commit(
+        '-S', f'--gpg-sign={signingkey}', '-m', '"my signed commit"')
 
-    # Set global Git user
-    repo.config_writer().set_value("user", "name", "A committer").release()
-    repo.config_writer().set_value("user", "email", "committer@example.com").release()
 
-    # Import private key
-    gpg = gnupg.GPG(gnupghome='/root/.gnupg', verbose=False, use_agent=True)
-    gpg.import_keys(gpg_private_key, passphrase=passphrase)
+def print_commit_info(temp_dir):
+    execute_console_command(f'cd {temp_dir} && git log --show-signature', True)
 
-    # Preset passphrase using gpg-connect-agent:
-    preset_passphrase_command = f'gpg-connect-agent \'PRESET_PASSPHRASE {keygrip} -1 {hex_passphrase}\' /bye'
-    execute_console_command(preset_passphrase_command)
 
-    repo.git.commit('-S', f'--gpg-sign={signingkey}', '-m', '"my signed commit"',
-                    author='"A committer <committer@example.com>"')
+def main(temp_dir, gpg_private_key, passphrase, signingkey, keygrip):
+
+    set_gpg_configuration(gpg_private_key, passphrase, keygrip)
+
+    create_signed_commit(temp_dir, signingkey)
 
-    # Print commit info
-    execute_console_command(f'cd {temp_dir} && git log --show-signature')
+    print_commit_info(temp_dir)
 
 
 if __name__ == "__main__":
@@ -78,4 +118,15 @@ def main(gpg_private_key, passphrase):
     gpg_private_key = os.getenv('GPG_PRIVATE_KEY').replace(r'\n', '\n')
     passphrase = os.environ.get('PASSPHRASE')
 
-    main(gpg_private_key, passphrase)
+    # TODO: get signingkey and keygrip from private key
+
+    signingkey = '27304EDD6079B81C'
+
+    # Of previous signingkey [master] key 88966A5B8C01BD04F3DA440427304EDD6079B81C
+    # It has to be the keygrip of the key you are using to sign commits.
+    keygrip = '449972AC9FF11BCABEED8A7AE834C4349CC4DBFF'
+
+    # Create temp dir for the example
+    temp_dir = create_temp_dir()
+
+    main(temp_dir, gpg_private_key, passphrase, signingkey, keygrip)