Running the ShotFactory without a ShotServer

Since milestone:0.4-beta2 it is possible to run the ShotFactory without a ShotServer installation.

Create queue and output folder

Create two folders, one for the screenshot request queue, and one for the resulting PNG files.

$ mkdir queue output

Install the ShotFactory and run it

See InstallFactory for installation instructions.

When you run it, specify the queue and output folders on the command line. The folders used below are examples. They can be anywhere, but the ShotFactory must have read and write access to both of them.

shotfactory.py --queue /var/spool/shotfactory/queue --output /var/www/png

You can generate thumbnails too. The following example saves the original PNG files, and also thumbnails that are 640 and 120 pixels wide, in the output folders original, large and small. These three folders must already exist (in the current directory, because they're specified as relative paths here). This feature requires the pnmscale program from the netpbm package.

shotfactory.py --queue queue --output original --resize-output 640 large --resize-output 120 small

If you only need the first screen of each website, you can limit the number of pages to scroll down. This is useful for faster processing.

shotfactory.py --max-pages 1

To see a complete list of available options:

shotfactory.py --help

Parallel operation

On Linux, you can run several screenshot factories on the same machine (using separate user accounts).

If you store the queue and output folders on a NFS share, several machines can work together. The file system must support atomic renames to avoid race conditions. Otherwise, two factories may process the same screenshot request.

Request screenshots

Now you can request screenshots by creating files in the queue directory, like this:

$ echo url http://www.example.com/ > queue/123
$ echo url http://www.example.org/ > queue/abc

If everything works, the ShotFactory will create the screenshot files 123.png and abc.png in the output folder.

Here's a more complete example for a screenshot request file:

request 123
url http://www.example.com/
width 1024
height 768
bpp 24
browser Firefox
command firefox

If the request parameter is given, its value will be the name of the screenshot file, with .png appended. Otherwise, the name of the screenshot request file will be used, also with .png added to it.

All other parameters except url are optional. Their default values are as in the example above.

If you want to run StandaloneInternetExplorer , you need to add the major and minor version of IE appropriate to the IE binary you're using. Failure to do this will result in KeyError in the start_browser method of msie.pyc.

Here's an example of the above request file, only designed for IE6. It assumes that you have extracted IE6 standalone to a directory called "ie6" inside the ShotFactory directory.

request 123
url http://www.example.com/
width 1024
height 768
bpp 24
browser MSIE
command ie6\iexplore.exe
major 6
minor 0