tableau-dashbhoarder

"Hoards" dashboards from Tableau Server or Tableau Cloud, to local images. In other words, kind of an automated downloader of Tableau dashboards.

Why? I use them to display a dashboard at home on a small display attached to a Raspberry Pi Zero W. It could technically display the interactive, embedded dashboard on a web page, but the Pi Zero W is a very lightweight computer. Hence, it is much faster to take the "lightweight approach" where the image gets downloaded beforehand and then displayed later.

Installation

Requires Python 3.x, probably - developed with Python 3.10.4, so that should work.

Currently, the installation simply goes though git clone and Python virtualenv. In brief:

• Clone:
  git clone https://github.com/timothyvermeiren/tableau-dashbhoarder
• Work from within that directory:
  cd tableau-dashbhoarder
• Create virtualenv:
  • If virtualenv is not installed yet, get it first:
    python -m pip install virtualenv
  • Actually create it:
    python -m virtualenv .venv
• Activate the virtualenv:
  • Windows:
    .venv\Scripts\activate
  • Linux:
    source .venv/bin/activate
• Install required modules:
  python -m pip install -r requirements.txt
• That should be it. Test according to the examples under Usage, below.

Usage

Running

From the command line, the tool is run "in" the virtualenv, through main.py, with just two arguments:

• --destination-path: a default destination path (i.e. output directory) to fall back to if no path has been specified for content specifically.
• --definitions-file: defines which content is to be hoarded, from where, to where. This is the key to how to tool works, explained below.

In other words, a simple example (on Windows):
.venv\Scripts\python.exe main.py --definitions-file .\config\definitions.json --destination-path .

"Definitions" and concepts

The manner in which the script will run, which content it will download, where it will be stored, etc., is referred to as the Definitions. These definitions are to be provided in the definitions JSON file, and the following rules and concepts apply.

There are two components to the definitions file:

• The sources part, containing the references to the Tableau environment(s) from which content will be hoarded.
  • Each source has a unique id, which will be referred to from the next section.
  • Aside from that, the Server/Online URL, Personal Access Token, etc. are defined here.
• The content part, which lists what will be downloaded, as well as where and how.
  • Name and comment values are used to label the content.
  • There is a source field referring to the sources' id from above.
  • There is a url field that can simply be copied from the browser - a reference to the view on Tableau Server or Online. The information that's really extracted from here is the end of the base URL, usually WorkbookName/ViewName.
  • Finally, there is an optional destination key to specify where the output will be written. The extension is added automatically to the filename. Either or both of filename and path can be left out, in which case the tool will revert to defaults.

An example definitions file is provided under config/definitions.json.template.

To do

• Implement proper credential management (through keyring, probably).
• Implement "content type" so PDF or PPT can be downloaded aside from PNG.