| Jinja | |
| Author: | Armin Ronacher |
| Logo Size: | 200px |
| Released: | [1] |
| Programming Language: | Python |
| Genre: | Template engine |
| License: | BSD License |
Jinja is a web template engine for the Python programming language. It was created by Armin Ronacher and is licensed under a BSD License. Jinja is similar to the Django template engine but provides Python-like expressions while ensuring that the templates are evaluated in a sandbox. It is a text-based template language and thus can be used to generate any markup as well as source code.
The Jinja template engine allows customization of tags,[2] filters (for formatting or transforming values[3]), tests (for evaluating conditions[3]), and globals.[4] Also, unlike the Django template engine, Jinja allows the template designer to call functions with arguments on objects.Jinja is Flask's default template engine [5] and it is also used by Ansible,[6] Trac, and Salt.[7] It is also used to make SQL macros, for example for use with dbt.[8]
Some of the features of Jinja are:[9]
Jinja, like Smarty, also ships with an easy-to-use filter system similar to the Unix pipeline.
The syntax for printing output in Jinja is using the double curly braces, for example <nowiki>{{ Hello, World! }}</nowiki>.
Statements which set variables in jinja or those which do not have an output can be wrapped within {% and %}, using the set keyword. For example foo with a value of 42.
Similar to above, comments in jinja can be written using a number sign (#) instead of a percentage (%), for example, <nowiki>{# helpful comment #}</nowiki>.
The syntax for creating a filter in Jinja is a vertical bar (|), for example <nowiki>{{ variable|filter }}</nowiki>. A variable can have multiple filters, for example <nowiki>{{ variable|filter|filter }}</nowiki>).
The syntax for creating a test in Jinja is the keyword is as well as the conditions for evaluating the validity of a test, such as for example
For loops can be used to iterate over sequences, while retaining their object properties. The following example demonstrates iterating over a list of users with and fields.
Here is a small example of a template file example.html.jinja:[10] -) after the tag {%: If you add a minus sign (-) to the start or end of a block (e.g. a For tag), a comment, or a variable expression, the whitespaces before or after that block will be removed.[11]