CODEWITHSUNDEEP
pythontemplatesjinja2
pjain
pjain

Reputation: 683

How to use special characters in template variables in jinja2?

I have a requirement where I want to render values containing ".", "..", "/" and "//" in jinja2.

For example I have a dictionary :

values= {'pre_package_information[1]/comment': 'Device: 14.2', 'post_package_information[1]/comment': 'Device: 14.2-2'}

Now I am rendering this value using jinja:

mssg= "Test Succeeded!! Checking Device version for 14.2 release {{pre_package_information[1]/comment}}"
jinja2.Template(mssg).render(values)

But it is giving error: 

jinja2.exceptions.UndefinedError: 'pre_package_information' is undefined

Looks like it is not taking "[" and "/" in templates. How to pass these special characters. I faced problems with other characters also like "." and ".."

Upvotes: 1

Views: 9334

Answers (2)

Martijn Pieters
Martijn Pieters

Reputation: 1121316

Jinja requires that all top-level names are valid Python identifiers; see the Notes on identifiers section:

Jinja2 uses the regular Python 2.x naming rules. Valid identifiers have to match [a-zA-Z_][a-zA-Z0-9_]*.

Either provide identifiers that match that requirement, or wrap your dictionary in another to indirectly look up your keys in that:

values = {'pre_package_information[1]/comment': 'Device: 14.2',  'post_package_information[1]/comment': 'Device: 14.2-2'}
mssg= ("Test Succeeded!! Checking Device version for 14.2 release "
       "{{values['pre_package_information[1]/comment']}}")
jinja2.Template(mssg).render(values=values)

Note that here the values dictionary is passed in as a keyword argument, so it'll be accessible as values in the template.

Demo:

>>> import jinja2
>>> values = {'pre_package_information[1]/comment': 'Device: 14.2',  'post_package_information[1]/comment': 'Device: 14.2-2'}
>>> mssg= ("Test Succeeded!! Checking Device version for 14.2 release "
...        "{{values['pre_package_information[1]/comment']}}")
>>> jinja2.Template(mssg).render(values=values)
u'Test Succeeded!! Checking Device version for 14.2 release Device: 14.2'

Upvotes: 4

adarsh
adarsh

Reputation: 6978

The way you access the variable in the template needs to be like this

{{ values['pre_package_information[1]/comment'] }}

and call the render like render(values=values)

Just like in python you cannot have variables with special characters

Upvotes: 2

Related Questions