ChatGPT GIt Commit Message Generator

ccm.sh

#!/usr/bin/env bash
# shellcheck source=/dev/null disable=SC2155
#=============================================================================
#     FileName : ccm.sh
#       Author : [email protected]
#      Created : 2025-03-21 03:34:24
#   LastChange : 2025-04-07 15:23:48
#  Description : ccm - [c]hatgpt [c]ommit [m]essage generator
#                +----------------------+--------------------+------------+
#                | ENVIRONMENT VARIABLE | DEFAULT VALUE      | NOTES      |
#                +----------------------+--------------------+------------+
#                | COMMITX_MODEL        | gpt-4-1106-preview | -          |
#                | COMMITX_TEMPERATURE  | 0.3                | -          |
#                | OPENAI_API_KEY       | env.OPENAI_API_KEY | mandatory* |
#                +----------------------+--------------------+------------+
#=============================================================================

set -euo pipefail

# OpenAI Models:
# +----------------------------+------------------+
# | MODEL NAME                 | CONTEXT (TOKENS) +
# +----------------------------+------------------+
# | gpt-3.5-turbo              | 4,096            |
# | gpt-3.5-turbo-16k          | 16,384           |
# | gpt-4                      | 8,192            |
# | gpt-4-turbo                | 128,000          |
# | gpt-4-1106-preview         | 128,000          |
# | gpt-4.5-preview            | 128,000          |
# | gpt-4.5-preview-2025-02-27 | 128,000          |
# | gpt-4o                     | 128,000          |
# | gpt-4o-mini                | 128,000          |
# | o1                         | 200,000          |
# | o1-mini                    | 128,000          |
# | o1-preview                 | 128,000          |
# | o1-pro                     | 200,000          |
# | o3-mini                    | 200,000          |
# +----------------------------+------------------+

# credit: https://github.com/ppo/bash-colors
# shellcheck disable=SC2015,SC2059
c() { [ $# == 0 ] && printf "\e[0m" || printf "$1" | sed 's/\(.\)/\1;/g;s/\([SDIUFNHT]\)/2\1/g;s/\([KRGYBMCW]\)/3\1/g;s/\([krgybmcw]\)/4\1/g;y/SDIUFNHTsdiufnhtKRGYBMCWkrgybmcw/12345789123457890123456701234567/;s/^\(.*\);$/\\e[\1m/g'; }
showHelp() { echo -e "${USAGE}"; }

declare model="${COMMITX_MODEL:-gpt-4-1106-preview}"
declare temperature="${COMMITX_TEMPERATURE:-0.3}"
declare OPENAI_API_KEY="${OPENAI_API_KEY:? OPENAI_API_KEY not set}"
declare ME="$(basename "${BASH_SOURCE[0]:-$0}")"
declare USAGE="""
NAME
  ${ME} - Generate a Git commit message using OpenAI API

USAGE
  $(c Ys)\$ ${ME}$(c) $(c Wdi)[$(c)$(c Gis)options$(c)$(c Wdi)]$(c) $(c Wdi)[$(c)$(c Bi)--$(c) $(c Mi)GIT DIFF ARGUMENTS$(c)$(c Wdi)]$(c)

OPTIONS
  $(c Gis)--help$(c), $(c Gis)-h$(c)           Show this help message

GIT DIFF ARGUMENTS
  Anything after $(c Bi)--$(c) is passed directly to $(c Bi)\`git diff\`$(c).

EXAMPLES
  $(c Ys)\$ ${ME}$(c)                       # use unstaged diff
  $(c Ys)\$ ${ME}$(c) $(c Bi)--$(c) $(c Mi)--cached$(c)           # use staged diff
  $(c Ys)\$ ${ME}$(c) $(c Bi)--$(c) $(c Mi)HEAD^..HEAD$(c)        # compare specific commits
  $(c Ys)\$ ${ME}$(c) $(c Bi)--$(c) $(c Mi)--cached$(c) $(c Bi)--$(c) $(c Mi)src/$(c)   # diff staged files in src/

ENVIRONMENT VARIABLES
  COMMITX_MODEL         model to use (default: $(c Ci)gpt-4-1106-preview$(c))
  COMMITX_TEMPERATURE   temperature for model response (default: $(c Ci)0.3$(c))
  OPENAI_API_KEY$(c R)*$(c)       your OpenAI API key ($(c Ri)required$(c), read from $(c i)environment variables$(c))
"""
declare -a diffOpt=()


while [[ $# -gt 0 ]]; do
  case "$1" in
    --help | -h ) showHelp; exit 0 ;;
    # pass everything after -- to git
    --          ) shift; diffOpt+=("$@"); break ;;
    *           ) echo -e "$(c Ri)ERROR$(c): unknown option: '$(c Mi)$1$(c)'. try $(c Gi)-h$(c)/$(c Gi)--help$(c). exit ..." >&2; exit 1 ;;
  esac
done

diff=$(git --no-pager diff --color=never "${diffOpt[@]}")
prompt="Generate a Git commit message in the Conventional Commits format, with the following structure:

<type>(<scope1,scope2,...>): short summary

- detail 1
- detail 2
- ...

Use multiple scopes if the diff includes changes in multiple areas.
Use markdown-style bullet points for details.
Do not include explanations or code.
Base it on the following diff:

${diff}
"

payload=$(jq -n \
  --arg model "${model}" \
  --arg temp "${temperature}" \
  --arg prompt "${prompt}" \
  '{
    model: $model,
    temperature: ($temp | tonumber),
    messages: [
      { role: "system", content: "You are an assistant that writes Git commit messages." },
      { role: "user", content: $prompt }
    ]
  }')

curl -s https://api.openai.com/v1/chat/completions \
  -H "Authorization: Bearer ${OPENAI_API_KEY}" \
  -H "Content-Type: application/json" \
  -d "${payload}" |
jq -r '.choices[0].message.content'

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