Add README.md

README.md

@@ -0,0 +1,84 @@
+# gdsync - `rsync` like file sync tool
+
+===========
+
+[![Build Status](https://travis-ci.org/kbinani/gdsync.svg?branch=master)](https://travis-ci.org/kbinani/gdsync)
+[![Coverage Status](https://coveralls.io/repos/github/kbinani/gdsync/badge.svg?branch=master)](https://coveralls.io/github/kbinani/gdsync?branch=master)
+
+# Installation
+
+```
+git clone https://github.com/kbinani/gdsync.git
+cd gdsync
+bundle install
+```
+
+# Authentication
+
+The first time you upload to/download from Google Drive, gdsync will prompt authentication message like this:
+
+```
+1. Open this page:
+https://accounts.google.com/o/oauth2/auth?access_type=offline&client_id=788008427451-1h3lt65qc87afhcm1fvh1h3gliut5ivq.apps.googleusercontent.com&redirect_uri=urn:ietf:wg:oauth:2.0:oob&response_type=code&scope=https://www.googleapis.com/auth/drive%20https://spreadsheets.google.com/feeds/
+
+2. Enter the authorization code shown in the page:
+```
+
+You have to open the web page and follow the instruction by Google. Then paste authentication code. The autentication code will be stored to `config.json` under the project root directory.
+
+# Usage
+
+`gdsync` has a subset of `rsync(1)` options. Supported `rsync` options are:
+
+```
+ -v, --verbose                    increase verbosity
+ -c, --checksum                   skip based on checksum, not mod-time & size
+ -a, --archive                    archive mode; same as -rt
+ -r, --recursive                  recurse into directories
+ -u, --update                     skip files that are newer on the receiver
+ -d, --dirs                       transfer directories without recursing
+ -t, --times                      preserve time
+ -n, --dry-run                    show what would have been transferred
+     --existing                   skip creating new files on receiver
+     --ignore-existing            skip updating files that exist on receiver
+     --remove-source-files        sender removes synchronized files (non-dir)
+     --delete                     delete extraneous files from dest dirs
+     --max-size=SIZE              don't transfer any file larger than SIZE
+     --min-size=SIZE              don't transfer any file smaller than SIZE
+ -I, --ignore-times               don't skip files that match size and time
+     --size-only                  skip files that match in size
+```
+
+## Local to Google Drive sync
+
+```
+ruby gdsync.rb --archive /path/to/source/dir/ googledrive://path/to/destination/dir
+```
+
+## Google Drive to Local sync
+
+```
+ruby gdsync.rb --archive googledrive://path/to/source/dir/ /path/to/destination/dir
+```
+
+## Google Drive to Google Drive sync
+
+```
+ruby gdsync.rb --archive googledrive://path/to/soruce/dir/ googledrive://path/to/destination/dir
+```
+
+## Local to Local sync
+
+It is possible to sync between local directories with gdsync, but rsync is better choice in this case.
+
+# License
+
+The MIT License
+
+# Author
+
+@kbinani
+
+# Notice
+
+`gdsync` comes with ABSOLUTELY NO WARRANTY.