Button up the last of the functionality

* Handles all of the shell exporting capabilities.
  Tests adjusted to handle a mock config.

* Adds Dockerfile for development purposes similar to the parent proj

* Adds legacy menu capabilities

Author: tomice

Dockerfile

@@ -0,0 +1,35 @@
+# Use the official Python image as the base image
+# and setup the env vars necessary
+FROM python:3.9-slim
+ENV PYTHONUNBUFFERED=1
+ENV PYTHONDONTWRITEBYTECODE=1
+
+# Set the working directory inside the container
+WORKDIR /app
+
+# Install git as it's our only dep
+RUN apt-get update && apt-get install -y git && apt-get clean
+
+# Copy the requirements and configuration files first for caching
+COPY pyproject.toml setup.py MANIFEST.in ./
+
+# Install build dependencies and the project in editable mode
+RUN pip install --upgrade pip setuptools
+RUN pip install -e .
+
+# Copy the rest of the stuff
+COPY . .
+
+# Initialize a basic git repo
+RUN git init && \
+    git config user.name "Docker" && \
+    git config user.email "[email protected]" && \
+    git add . && \
+    git commit -m "Initial commit" || echo "Already a git repository"
+
+# NOTE: Should we add dummy commits?
+#       Thought - we can dogfood and clone the git-py-stats repo inside here
+
+# Command to run the CLI tool with help option
+CMD ["git-py-stats", "--help"]
+

README.md

@@ -78,16 +78,16 @@ project's version. Not Yet Implemented means it does not exist yet:
 | **Git Commits per Hour by Author**              | Completed ✔️            | Shows hourly commit count hour by given author.         |
 | **Git Commits per Timezone**                    | Completed ✔️            | Counts commits based on timezones.                      |
 | **Git Commits per Timezone by Author**          | Completed ✔️            | Shows timezone-based commit counts by given author.     |
-| **Since Variable Adjustable by User**           | Not Yet Implemented ❌ | Allows users to set the starting point for commit logs. |
-| **Until Variable Adjustable by User**           | Not Yet Implemented ❌ | Enables users to define the end point for commit logs.  |
-| **Pathspec Variable Adjustable by User**        | Not Yet Implemented ❌ | Filters commits based on specified path patterns.       |
-| **Merge View Variable Adjustable by User**      | Not Yet Implemented ❌ | Controls the inclusion of merge commits in views.       |
-| **Limit Variable Adjustable by User**           | Not Yet Implemented ❌ | Sets the maximum number of commits to display.          |
-| **Log Options Variable Adjustable by User**     | Not Yet Implemented ❌ | Customizes git log command options.                     |
-| **Legacy Theme**                                | Not Yet Implemented ❌ | Restores the previous visual theme of the application.  |
+| **Since Variable Adjustable by User**           | Completed ✔️            | Allows users to set the starting point for commit logs. |
+| **Until Variable Adjustable by User**           | Completed ✔️            | Enables users to define the end point for commit logs.  |
+| **Pathspec Variable Adjustable by User**        | Completed ✔️            | Filters commits based on specified path patterns.       |
+| **Merge View Variable Adjustable by User**      | Completed ✔️            | Controls the inclusion of merge commits in views.       |
+| **Limit Variable Adjustable by User**           | Completed ✔️            | Sets the maximum number of commits to display.          |
+| **Log Options Variable Adjustable by User**     | Completed ✔️            | Customizes git log command options.                     |
+| **Legacy Theme**                                | Completed ✔️            | Restores the previous visual theme of the application.  |
 | **Linux Package Install**                       | Not Yet Implemented ❌ | Allows Linux users to install via a package manager.    |
 | **macOS Package install**                       | Not Yet Implemented ❌ | Allows macOS users to install via brew.                 |
-| **Docker Development Image**                    | Not Yet Implemented ❌ | Provides a Docker development image for CI/CD.          |
+| **Docker Development Image**                    | Completed ✔️            | Provides a Docker development image for CI/CD.          |
 
 ## Changes from Original
 
@@ -96,15 +96,16 @@ there may be instances where this version differs from the base project by desig
 The following is a list of differences that this project will maintain compared to
 the parent project:
 
-* Author, dates, and branch names can be passed via cmdline without interaction
+- Author, dates, and branch names can be passed via cmdline without interaction
   by the user. This means you can now do `git-py-stats -L "John Doe"` instead
   of being prompted to enter the name after executing the non-interactive cmd.
-* CSV output is now saved to a file instead of printing out to the terminal.
+- CSV output is now saved to a file instead of printing out to the terminal.
   This file will be saved to wherever the process was executed. The name will
   be `git_daily_stats.csv`
-* JSON output is saved to a file wherever the process was executed instead of
+- JSON output is saved to a file wherever the process was executed instead of
   one that is provided by the user. The name will be `git_log.json`
-* The New Contributors function shows the user's name next to the email in case
+- JSON and CSV formatting has changed slightly from the original.
+- The New Contributors function shows the user's name next to the email in case
   no known mailmap has been implemented for that user.
 
 ## Requirements
@@ -216,6 +217,92 @@ For a full list of available options, run:
 git-py-stats --help
 ```
 
+### Advanced Usage
+
+It is possible for `git-py-stats` to read shell environment variables just like
+`git-quick-stats` does. As it aims to maintain 1:1 compatibility, all of the
+same arguments work the same as the parent project.
+
+#### Git log since and until
+
+You can set the variables `_GIT_SINCE` and/or `_GIT_UNTIL` before running
+`git-py-stats` to limit the git log.
+These work similar to git's built-in `--since` and `--until` log options.
+
+```bash
+export _GIT_SINCE="2017-01-20"
+export _GIT_UNTIL="2017-01-22"
+```
+
+Once set, run `git-py-stats` as normal. Note that this affects all stats that
+parse the git log history until unset.
+
+#### Git log limit
+
+You can set variable `_GIT_LIMIT` for limited output.
+It will affect the "changelogs" and "branch tree" options.
+The default limit is `10`.
+
+```bash
+export _GIT_LIMIT=20
+```
+
+#### Git log options
+
+You can set `_GIT_LOG_OPTIONS` for
+[git log options](https://git-scm.com/docs/git-log#_options):
+
+```bash
+export _GIT_LOG_OPTIONS="--ignore-all-space --ignore-blank-lines"
+```
+
+#### Git pathspec
+
+You can exclude a directory from the stats by using
+[pathspec](https://git-scm.com/docs/gitglossary#gitglossary-aiddefpathspecapathspec)
+
+```bash
+export _GIT_PATHSPEC=':!directory'
+```
+
+You can also exclude files from the stats.
+Note that it works with any alphanumeric, glob, or regex that git respects.
+
+```bash
+export _GIT_PATHSPEC=':!package-lock.json'
+```
+
+#### Git merge view strategy
+
+You can set the variable `_GIT_MERGE_VIEW` to enable merge commits to be part
+of the stats by setting `_GIT_MERGE_VIEW` to `enable`. You can also choose to
+only show merge commits by setting `_GIT_MERGE_VIEW` to `exclusive`.
+Default is to not show merge commits.
+These work similar to git's built-in `--merges` and `--no-merges` log options.
+
+```bash
+export _GIT_MERGE_VIEW="enable"
+export _GIT_MERGE_VIEW="exclusive"
+```
+
+#### Git branch
+
+You can set the variable `_GIT_BRANCH` to set the branch of the stats.
+Works with commands `--git-stats-by-branch` and `--csv-output-by-branch`.
+
+```bash
+export _GIT_BRANCH="master"
+```
+
+#### Color themes
+
+You can change to the legacy color scheme by toggling the variable
+`_MENU_THEME` between `default` and `legacy`
+
+```bash
+export _MENU_THEME="legacy"
+```
+
 ## Development
 
 This section is currently under development and is changing rapidly as we work

git_py_stats/config.py

@@ -0,0 +1,120 @@
+"""
+Handles reading configuration settings from environment variables.
+"""
+
+import os
+from datetime import datetime
+from typing import Dict, Union, Optional
+from git_py_stats.git_operations import run_git_command
+
+# TODO: This is a rough equivalent of what the original program does.
+#       However, that doesn't mean this is the correct way to handle
+#       this type of operation since these are not much different
+#       from global vars. Granted, they're global in the user's shell env
+#       to begin with, but since we now have the power of Python, we can
+#       probably handle this in a more expressive way.
+#       Context and Decorators? Command Factory to leverage Dependency
+#       Injection and the Command pattern? Centralized Config Manager?
+#       Marked as future possible refactor.
+def get_config() -> Dict[str, Union[str, int]]:
+    """
+    Reads configuration from environment variables and sets default values.
+    These are the original program's environment variables:
+
+    Environment Variables:
+        _GIT_SINCE (str): Equivalent to git's --since flag. 
+            If not set, defaults to the first commit date in the repository.
+        _GIT_UNTIL (str): Equivalent to git's --until flag. 
+            If not set, defaults to the current system date/time upon exec
+            of the program.
+        _GIT_PATHSPEC (str): Specifies files or directories to include/exclude in stats. 
+            Defaults to "--" which means to skip over this option.
+        _GIT_MERGE_VIEW (str): Merge commit view strategy. Options:
+            - 'exclusive' to show only merge commits.
+            - 'enable' to use the user's default merge view from the conf.
+               Default is usually to show both regular and merge commits.
+            - Any other value defaults to '--no-merges' currently.
+        _GIT_LIMIT (int): Limits the git log output. Defaults to 10.
+        _GIT_LOG_OPTIONS (str): Additional git log options. Default is empty.
+        _MENU_THEME (str): Toggles between the default theme and legacy theme.
+            - 'legacy' to set the legacy theme
+            - Empty to set the default theme
+
+    Returns:
+        Dict[str, Union[str, int]]: A dictionary containing the configuration options:
+            - 'since' (str): Git command option for the start date.
+            - 'until' (str): Git command option for the end date.
+            - 'pathspec' (str): Git command option for pathspec.
+            - 'merges' (str): Git command option for merge commit view strategy.
+            - 'limit' (int): Git log output limit.
+            - 'log_options' (str): Additional git log options.
+            - 'menu_theme' (str): Menu theme color.
+    """
+    config: Dict[str, Union[str, int]] = {}
+
+    # _GIT_SINCE
+    git_since: Optional[str] = os.environ.get('_GIT_SINCE')
+    if git_since:
+        config['since'] = f"--since={git_since}"
+    else:
+        # Get the earliest commit date in the repo
+        earliest_commit_date: Optional[str] = run_git_command(['git', 'log', '--reverse', '--format=%ad'])
+        if earliest_commit_date:
+            first_commit_date: str = earliest_commit_date.split('\n')[0]
+            config['since'] = f"--since='{first_commit_date}'"
+        else:
+            config['since'] = ''
+
+    # _GIT_UNTIL
+    git_until: Optional[str] = os.environ.get('_GIT_UNTIL')
+    if git_until:
+        config['until'] = f"--until={git_until}"
+    else:
+        # Get the current date/time upon exec of the program
+        now: str = datetime.now().strftime('%a, %d %b %Y %H:%M:%S %Z')
+        config['until'] = f"--until='{now}'"
+
+    # _GIT_PATHSPEC
+    git_pathspec: Optional[str] = os.environ.get('_GIT_PATHSPEC')
+    if git_pathspec:
+        config['pathspec'] = f"-- {git_pathspec}"
+    else:
+        config['pathspec'] = "--"
+
+    # _GIT_MERGE_VIEW
+    git_merge_view: str = os.environ.get('_GIT_MERGE_VIEW', '').lower()
+    if git_merge_view == 'exclusive':
+        config['merges'] = '--merges'
+    elif git_merge_view == 'enable':
+        config['merges'] = ''
+    else:
+        config['merges'] = '--no-merges'
+
+    # _GIT_LIMIT
+    git_limit: Optional[str] = os.environ.get('_GIT_LIMIT')
+    if git_limit:
+        # Slight sanitization, but we're still gonna wild west this a bit
+        try:
+            config['limit'] = int(git_limit)
+        except ValueError:
+            print("Invalid value for _GIT_LIMIT. Using default value 10.")
+            config['limit'] = 10
+    else:
+        config['limit'] = 10
+
+    # _GIT_LOG_OPTIONS
+    # NOTE: We'll need to sanitize our entire git command
+    git_log_options: Optional[str] = os.environ.get('_GIT_LOG_OPTIONS')
+    if git_log_options:
+        config['log_options'] = git_log_options
+    else:
+        config['log_options'] = ''
+    
+    # _MENU_THEME
+    menu_theme: Optional[str] = os.environ.get('_MENU_THEME')
+    if menu_theme == 'legacy':
+        config['menu_theme'] = 'legacy'
+    else:
+        config['menu_theme'] = ''
+
+    return config