git_transactor

Overview

This code performs a series of git add and git rm transactions on a local repository, and then pushes the updates to a remote repository.

Preconditions

A git client is installed on the system.
The user running the script has write privileges on both the local and remote repositories.
The user running the script has read privileges on files being added to the local repository.

Status

in production

Available Functionality

rake is used to execute git_transactor tasks.

rake git_transactor:process_and_push   # Process entries in queue and push to remote
rake git_transactor:pull               # Pull from remote repository to local repository
rake git_transactor:pull_process_push  # Pull from remote repository, process queue, and push back to remote repository
rake git_transactor:push               # Push from local repository to remote repository
rake git_transactor:setup:queue        # Initialize queue structure in QUEUE_ROOT directory

The following environment variables must be set when running a git_transactor rake task:

GT_LOCAL_REPO       # the path to the local EAD repository
GT_SOURCE_PATH      # the path to the directory from which to copy EAD files
GT_QUEUE_ROOT       # the path to the Git Transactor queue directory structure created via
                    #   rake git_transactor:setup_queue task
GT_REMOTE_REPO_URL  # the remote repository URL

e.g.,
rake git_transactor:pull_process_push LOCAL_REPO='./super_duper_files' \
  SOURCE_PATH='/path/to/source/files' QUEUE_ROOT='/path/to/queue/root' \
  REMOTE_REPO_URL='git@github.com:example/super_duper_files.git'

`pull_process_push` execution overview

as the name implies, the task first executes a pull to synchronize the local repo with the remote repository
then, a process_queue operation is executed. process_queue operation does the following:

checks for "queue entry files" in QUEUE_ROOT/queue directory
if the QUEUE_ROOT/queue directory is empty the script simply terminates with an exit status of 0
if the QUEUE_ROOT/queue directory is not empty, the script processes each queue entry file in the order of the queue entry filenames, from lowest to highest.
if a request is processed successfully, the queue entry file is moved to the QUEUE_ROOT/passed/ subdirectory
if a request is processed unsuccessfully, the queue entry file is moved to the QUEUE_ROOT/failed/ subdirectory.
after all queue entry files, the changes are committed to the local repository

the task next executes a push operation to synchronize the remote repository with the local repository

Queue Entry Files

Each queue entry file is named per the following template:

<YYYYMMDDTHHMMSSNNNNNNNNN.csv>, where:
  * YYYY = current year
  * MM   = current month,  zero-padded, range: 01-12
  * DD   = current day,    zero-padded  range: 01-31
  * T    = literal character T used as date/time delimiter
  * HH   = current hour,   zero-padded  range: 00-23 (note 24-hour format)
  * MM   = current minute, zero-padded, range: 00-59
  * SS   = current second, zero-padded, range: 00-59
  * NNNNNNNNN = current nanosecond, zero-padded, range: 000000000-999999999
  e.g., 20150227T113018273091611.csv

A queue-entry file contains a single line of comma-separated values that conform to the following template:

<command>,<absolute path to file being managed>
<command> must be either add or rm