Jinja2 templates as a visualization type

[ahrussell]

We often (ab)use Redash's ability to display arbitrary HTML in table visualizations. However, writing HTML within SQL queries is a huge pain. It would be nice to define + save custom visualizations that leverage Jinja2 templates. These would then be displayed similarly to the current table visualization.

For example, lets say you want to use HTML to color usernames red if they start with the letter 'A'. The current way you would do this is by writing this query:

SELECT
    CASE WHEN user like 'A%' THEN '<span style="color:red">' || user || '</span>'
         ELSE user
    END AS "Formatted Username"
FROM users

As the HTML gets longer, this kind of query gets harder to work with. Instead, I'd like to write this query:

SELECT
    user
FROM users

And then define a custom visualization with these fields (you can add more than one template per visualization):

• Output name: Formatted Username
• Jinja2 Template:

{% if user.startswith('A') %}
<span style="color:red"> {{ user }} </span>`
{% else %}
{{ user }}
{% endif %}