Since v2.7 there is selectattr: Filters a sequence of objects by applying a test to the specified attribute of each object, and only selecting the objects with the test succeeding. If no test is specified, the attribute’s value will be evaluated as a boolean. Example usage: {{ users|selectattr(“is_active”) }} {{ users|selectattr(“email”, “none”) }} Similar to … Read more
Your expression seems to work just fine. If I create a template with the jinja2 expression from your question: >>> import jinja2 >>> t = jinja2.Template(‘{{ test1 | replace(“value1″,”my_value1”) | replace(“value2″,”my_value2”) }}’) And then render it, passing in a value for test1 that contains both of the target replacement strings: >>> output = t.render(test1=”this has … Read more
Technically, because context is not passed as a named dictionary, a little work is required to generate a list of the context variables from inside a template. It is possible though. Define a Jinja context function to return the jinja2.Context object, which is essentially a dictionary of the global variables/functions Make that function available in … Read more
A better solution…. You can use startswith directly in field because field is a python String. {% if field.startswith(‘i-‘) %} More, you can use any String function, including str.endswith(), for example.
The index.js is probably not served by your flask instance, but it is most definitely not processed by your templateing engine and even if it would it would not have the same context as the html it is requested for. I think the cleanest solution would be to have an initiation function in your index.js … Read more
You have two choices here — the first is the way you did it — simply add the appropriate markup into a template (or a block if you want to be able to override it in templates which extend your first template.) The second way is to use Jinja2’s include function: {% block javascript %} … Read more
Use the special self variable to access the block by name: <title>{% block title %}{% endblock %} – {{ sitename }}</title> <!– … snip … –> <h1>{{ self.title() }}</h1>
Jinja2 also includes the range function which returns a sequence of numbers from start to end – 1, so you can use it with random: Your lucky number is: {{ range(1, 51) | random }}
It seems Jinja2 works differently: Use <input type=”hidden” name=”csrfmiddlewaretoken” value=”{{ csrf_token }}”> where in Django templates you use {% csrf_token %} source : http://exyr.org/2010/Jinja-in-Django/
After doing some more test, I found the answer : By doing the same template test, directly under python, without using django, debug messages are present. So it comes from django. The fix is in settings.py : One have to set DEBUG to True AND set TEMPLATE_DEBUG to False.