git_rails

#!/bin/bash
old_ref=$1
new_ref=$2

colors[0]='\033[1;32m'
colors[1]='\033[0;35m'
colors[2]='\033[0;33m'
colors[3]='\033[1;33m'
colors[4]='\033[0;34m'

no_color='\033[0m'

rand_color=$[ $RANDOM % 5 ]

if [ -z "$old_ref" ]; then
  old_ref=`git rev-parse ORIG_HEAD`
fi

if [ -z "$new_ref" ]; then
  new_ref=`git rev-parse HEAD`
fi

files_changed=`git diff $old_ref $new_ref --name-status`

# CHECK IF WE NEED TO DO A BUNDLE
bundle_changed=`echo "$files_changed" | grep $'M\tGemfile.lock'`
if [ ! -z "$bundle_changed" ]; then
  arr[0]="There are changes to Gemfile.lock, but don't worry - I've got you covered. Bundling now ..."
  arr[1]="'Bundling' isn't just an old-timey tradition, it's also what I'm doing right now!"
  arr[2]="Gemfile.lock has changed. COMMENCE RUNNING BUNDLE in 5 ... 4 ... 3 ... 2 ... 1!"

  rand=$[ $RANDOM % 3 ]
  echo "-----------------------------------------"
  echo -e ${colors[$rand_color]}${arr[$rand]}${no_color}
  echo "-----------------------------------------"

  bundle
fi

migrations=`git diff --name-status $old_ref $new_ref -- db/migrate | grep '^[AD]'`
if [ ! -z "$migrations" ]; then
  arr[0]="New database structure like what! Time to run migrations ..."
  arr[1]="Call me a crane for the way I'm handling these migrations!"
  arr[2]="Making sure the ol' db is up-to-date: it's migration time"
  rand=$[ $RANDOM % 3 ]

  echo "-----------------------------------------"
  echo -e ${colors[$rand_color]}${arr[$rand]}${no_color}
  echo "-----------------------------------------"

  for migration in $migrations
  do
    # CHECK THE MIGRATION TYPE AND CONTINUE TO THE FILENAME
    if [ $migration == "D" ]; then
      migration_type="down"
      continue
    elif [ $migration == "A" ]; then
      migration_type="up"
      continue
    fi

    # BUILD THE MIGRATION COMMAND FROM THE VERSION AND TYPE
    version=`echo "$migration" | cut -d'_' -f1 | cut -d'/' -f3`
    migrate_command="ActiveRecord::Migration.new.migration_context.migrations.detect {|d| d.version == $version}.migrate(:$migration_type) rescue ActiveRecord::Migrator.migrations('db/migrate').detect {|d| d.version == $version}.migrate(:$migration_type) rescue nil"

    # APPEND OR PREPREND TO THE COMMAND LIST DEPENDING ON MIGRATION TYPE
    if [[ $migration_type == "down" ]]; then
      # CHECKOUT DOWN MIGRATION AND SAVE PATH FOR CLEANUP
      git checkout "$old_ref" -- "$migration"
      migration_cleanup="$migration_cleanup $migration"
      migrate_command="$migrate_command;ActiveRecord::Base.connection.exec_query(\"DELETE FROM schema_migrations WHERE version = '$version'\") rescue nil"
      migrate_commands="$migrate_command;$migrate_commands"
    else
      migrate_command="$migrate_command;ActiveRecord::Base.connection.exec_query(\"INSERT INTO schema_migrations (version) VALUES ('$version') ON CONFLICT (version) DO NOTHING\") rescue nil"
      migrate_commands="$migrate_commands;$migrate_command"
    fi
  done

  # RUN THE MIGRATIONS (AND TEST PREPARE)
  bundle exec rails r "$migrate_commands"

  # CLEAN UP DOWN MIGRATIONS
  if [ ! -z "$migration_cleanup" ]; then
    git reset $new_ref -- $migration_cleanup
    rm $migration_cleanup
  fi
fi