Table of contents

• Description
• Usage
• Installation
• The hook
• Private group
• Tips. Tricks
• Known problems
• License
• Author

Description

This is a Bash script to download all mbox files from any Google group. Private groups require you to load cookies from file.

Installation

The script requires bash, sort, wget, sed, awk.

Make the script executable with chmod 755 and put them in your path (e.g, /usr/local/bin/.)

Usage

The first run

export _GROUP="mygroup"       # specify your group

export _RSS_NUM=50            # (optional. See Tips & Tricks.)
export _HOOK_FILE=/path/to.sh # (optional. See The Hook.)

./crawler.sh -sh              # first run for testing
./crawler.sh -sh > wget.sh    # save your script
bash wget.sh                  # downloading mbox files

./crawler.sh -rss > update.sh # using rss feed for updating

When you have some new emails in your google group, you can use -rss option, or you may need to clean up and remove some temporary files.

rm -fv $_GROUP/threads/t.*    # this is a must
rm -fv $_GROUP/msgs/m.*       # see also Tips & Tricks

If you want the script to re-scan the whole archive, try

_FORCE="true" ./crawler.sh -sh

or you simply delete all files under $_GROUP/ directory.

Private group

1. Export cookies for google domains from your browser and save them as file. Please use a Netscape format. See man wget or the following page for details:

   https://xiix.wordpress.com/2006/03/23/mozillafirefox-cookie-format/

   A sample cookie file is as below

    groups.google.com FALSE / FALSE 1461209169 G2_ADLT  1458617169721
    .google.com       TRUE  / FALSE 1474428370 NID      77=a-very-long-string
    .sstatic.net      TRUE  / FALSE 1490153162 __cfduid a-hash-of-some-thing
   

   (G2_ADLT available when you access some adult-contents group.)

2. Specify your cookie file by _WGET_OPTIONS:

    export _WGET_OPTIONS="--load-cookies /your/path/my_cookies.txt
                          --keep-session-cookies"
   

   Now every hidden group can be downloaded :)

The hook

If you want to execute a hook command after a mbox file is downloaded, you can do as below.

1. Prepare a Bash script file that contains a definition of __wget_hook command. The first argument is to specify an output filename, and the second argument is to specify an URL. For example, here is simple hook

    # $1: output file
    # $2: url (https://groups.google.com/forum/message/raw?msg=foobar/topicID/msgID)
    __wget_hook() {
      if [[ "$(stat -c %b "$1")" == 0 ]]; then
        echo >&2 ":: Warning: empty output '$1'"
      fi
    }
   

   In this example, the hook will check if the output file is empty, and send a warning to the standard error device.

2. Set your environment variable _HOOK_FILE which should be the path to your file. For example,

    export _GROUP=archlinuxvn
    export _HOOK_FILE=$HOME/bin/wget.hook.sh
   

   Now the hook file will be loaded in your future output script.

Tips and Tricks

0. If you clean your files (as below), you may notice that it will be very slow when re-downloading all files. You may consider to use the -rss option instead. This option will fetch data from a rss link.

   It's recommmeded to use the -rss option for daily update. By default, the number of items is 50. You can change it by the _RSS_NUM variable. However, don't use a very big number, because Google will ignore that.

1. Because Topics is a FIFO list, you only need to remove the last file. The script will re-download the last item, and if there is a new page, that page will be fetched.

    ls $_GROUP/msgs/m.* \
    | sed -e 's#\.[0-9]\+$##g' \
    | sort -u \
    | while read f; do
        last_item="$f.$( \
          ls $f.* \
          | sed -e 's#^.*\.\([0-9]\+\)#\1#g' \
          | sort -n \
          | tail -1 \
        )";
        echo $last_item;
      done
   

2. The list of threads is a LIFO list. If you want to rescan your list, you will need to delete all files under $_D_OUTPUT/threads/

3. You can set the time for mbox output files, as below

    ls $_GROUP/mbox/m.* \
    | while read FILE; do \
        date="$( \
          grep ^Date: $FILE\
          | head -1\
          | sed -e 's#^Date: ##g' \
        )";
        touch -d "$date" $FILE;
      done
   

   This will be very useful, for example, when you want to use the mbox files with mhonarc.

Known problems

This script can't recover emails from public groups unless you use valid cookies to download data.

When cookies are used, all emails are recovered, and you must filter them before making your archive public.

License

This work is released under the terms of a MIT license.

Author

This script is written by Anh K. Huynh.

He wrote this script because he couldn't resolve the problem by using nodejs, phantomjs, Watir.

New web technology just makes life harder, doesn't it?