# -*- coding: utf-8 """ The GitMIDI class that converts a Git repository’s log into MIDI music. """ from __future__ import print_function import os import shutil from midiutil.MidiFile import MIDIFile from StringIO import StringIO from git import Repo, Tree from git.objects.blob import Blob from time import sleep try: import pygame import pygame.mixer PYGAME_AVAILABLE = True except ImportError: PYGAME_AVAILABLE = False def get_file_sha(commit, file_name): """ Get the SHA1 ID of a file by its name, in the given commit. """ elements = file_name.split(os.sep) tree = commit.tree while True: try: element = elements.pop(0) if isinstance(tree[element], Tree): tree = tree[element] except (KeyError, IndexError): # The file has been deleted, return the hash of an empty file return 'e69de29bb2d1d6434b8b29ae775ad8c2e48c5391' if isinstance(tree, Blob): break return tree.hexsha class GitMIDI(MIDIFile): """ Class to hold repository data, and MIDI data based on that repository. """ LOG_CHANNEL = 0 FILE_CHANNEL = 1 def __setup_midi(self, track_title=None): """ Initialise the MIDI file. """ if self.__verbose: print("Preparing MIDI track…") if track_title is None: # TODO: Change this to something that connects to the repo self.addTrackName(0, 0, "Sample Track") self.addTempo(0, 0, self.__tempo) if self.__need_commits: self.addProgramChange(0, self.LOG_CHANNEL, 0, self.__program['commit']['program']) if self.__need_files: self.addProgramChange(0, self.FILE_CHANNEL, 0, self.__program['file']['program']) def __setup_repo(self): """ Setup repository and get the specified branch. """ if self.__verbose: print("Analyzing repository…") repo = Repo(self.__repo_dir) self.__branch_head = repo.heads[self.__branch].commit def __init__(self, repository=None, branch=None, verbose=None, scale=None, program=None, volume_range=None, skip=None, note_duration=None, max_beat_len=None, tempo=None): MIDIFile.__init__(self, 1) self.__verbose = verbose or False self.__written = False self.__repo_dir = repository or '.' self.__repo = None self.__branch = branch or 'master' self.__branch_head = None self.__repo_data = None self.__git_log = [] self.__mem_file = StringIO() self.__scale = scale self.__program = program self.__volume_deviation = min(abs(63 - (volume_range or 107)), 63) self.__pygame_inited = False self.__playing = False self.__skip = skip or 0 self.__note_duration = note_duration or 0.3 self.__max_beat_len = max_beat_len self.__tempo = tempo or 120 self.__need_commits = self.__program['commit']['program'] is not None self.__need_files = self.__program['file']['program'] is not None self.__setup_midi() self.__setup_repo() def gen_volume(self, deletions, insertions, modifier): """ Generate a volume based on the number of modified lines (insertions - deletions). deviation specifies the minimum and maximum volume (minimum is the value of deviation, maximum is 127 - deviation). """ return max( self.__volume_deviation, min(127 - self.__volume_deviation, 63 - deletions + insertions + modifier)) def sha_to_note(self, sha): """ Calculate note based on an SHA1 hash """ note_num = reduce(lambda res, digit: res + int(digit, 16), list(str(sha)), 0) % len(self.__scale) return self.__scale[note_num] def gen_beat(self, commit): """ Generate data for a beat based on a commit and its files. """ stat = commit.stats file_notes = [] file_count = 0 for file_name, file_stat in stat.files.items(): file_count += 1 if self.__max_beat_len is not None and \ self.__max_beat_len != 0 and \ file_count > self.__max_beat_len: break volume_mod = self.__program['file'].get('volume', 0) file_note = self.sha_to_note(get_file_sha(commit, file_name)) + \ self.__program['file']['octave'] * 12 file_volume = self.gen_volume(file_stat['deletions'], file_stat['insertions'], volume_mod) file_notes.append({ 'note': file_note, 'volume': file_volume, }) volume_mod = self.__program['commit'].get('volume', 0) commit_note = self.sha_to_note(commit.hexsha) + \ self.__program['commit']['octave'] * 12 commit_volume = self.gen_volume(stat.total['deletions'], stat.total['insertions'], volume_mod) return { 'commit_note': commit_note, 'commit_volume': commit_volume, 'file_notes': file_notes, } def gen_repo_data(self, force=False, callback=None): """ Populate __repo_data with the Git history data. If force is False and the repo_data is already calculated, we do not do anything. """ if self.__repo_data and not force: return if self.__verbose: print("Reading repository log…") self.__repo_data = [] counter = 0 to_process = [self.__branch_head] while len(to_process) > 0: counter += 1 # TODO: Make this 500 configurable if counter % 500 == 0 and self.__verbose: print("Done with {} commits".format(counter)) current_commit = to_process.pop() if callback is not None: callback(None, None) if current_commit not in self.__repo_data: self.__repo_data.append(current_commit) to_process += current_commit.parents if self.__verbose: print("{} commits found".format(counter)) print("Sorting commits…") self.__repo_data.sort(key=lambda commit: commit.authored_date) if self.__verbose: print("Generating MIDI data…") self.__git_log = [] current_commit = 0 commits_to_process = self.__repo_data[self.__skip:] commit_count = len(commits_to_process) for commit in commits_to_process: if callback: current_commit += 1 callback(commit_count, current_commit) self.__git_log.append(self.gen_beat(commit)) @property def repo_data(self): """ Get repository data for MIDI generation. """ if self.__repo_data is None: self.gen_repo_data(force=True) return self.__repo_data def write_mem(self): """ Write MIDI data to the memory file. """ self.writeFile(self.__mem_file) self.__written = True def export_file(self, filename): """ Export MIDI data to a file. """ if not self.__written: self.write_mem() with open(filename, 'w') as midi_file: self.__mem_file.seek(0) shutil.copyfileobj(self.__mem_file, midi_file) def generate_midi(self, callback=None): """ Generate MIDI data. """ if self.__verbose: print("Creating MIDI…") track = 0 time = 0 log_channel = 0 decor_channel = 1 log_length = len(self.__git_log) current = 0 # WRITE THE SEQUENCE for section in self.__git_log: current += 1 section_len = len(section['file_notes']) * self.__note_duration if callback is not None: callback(log_length, current) # Add a long note if self.__need_commits: self.addNote(track, log_channel, section['commit_note'], time, section_len, section['commit_volume']) if self.__need_files: for i, file_note in enumerate(section['file_notes']): self.addNote(track, decor_channel, file_note['note'], time + i * self.__note_duration, self.__note_duration, file_note['volume']) time += section_len def __init_pygame(self): """ Initialise pygame. """ if not PYGAME_AVAILABLE or self.__pygame_inited: return # Initialise pygame pygame.init() pygame.mixer.init() def play(self, track=False): """ Start MIDI playback. If pygame is not available, don’t do anything. """ if not PYGAME_AVAILABLE: return "pygame is not available, cannot start playback" if self.__verbose: print("Playing!") self.__init_pygame() self.__mem_file.seek(0) pygame.mixer.music.load(self.__mem_file) pygame.mixer.music.play() self.__playing = True if not track: while pygame.mixer.music.get_busy(): sleep(1) self.__playing = False def stop(self): """ Stop MIDI playback. """ if not PYGAME_AVAILABLE: return pygame.mixer.music.stop() def get_play_pos(self): """ Get current playback position from the mixer """ if not self.__playing: return None if pygame.mixer.music.get_busy(): return pygame.mixer.music.get_pos() else: self.__playing = False return None