I have a base.html template which I would like to use for all pages. This base.html contains a navigation
<nav>
<li>Home</li>
<li>bar</li>
</nav>
This is no problem when I'm on the same level (e.g. localhost:5000/whatever), but when I'm in a subfolder (e.g. localhost:5000/whatever/insert) the links break.
This can be fixed by making the relative links absolute, e.g.
<nav>
<li>Home</li>
<li>bar</li>
</nav>
However, I don't know how to get the base_url. If possible, I would like to avoid adding base_url to each render_template call. And, if possible, I would also like to avoid to set base_url manually.
How is this problem solved with Flask / Jinja2?
Don't worry about a base url; if home and foo are routes in your Flask app, use the url_for() function to build your URLs instead:
<nav>
<li>Home</li>
<li>bar</li>
</nav>
Also see the URL Building section of the Flask Quickstart documentation:
Why would you want to build URLs using the URL reversing function url_for() instead of hard-coding them into your templates?
Reversing is often more descriptive than hard-coding the URLs.
You can change your URLs in one go instead of needing to remember to
manually change hard-coded URLs.
You can change your URLs in one go instead of needing to remember to manually change hard-coded URLs
URL building handles escaping of special characters and Unicode data
transparently.
The generated paths are always absolute, avoiding unexpected behavior of relative paths in browsers.
If your application is placed outside the URL root, for example, in
/myapplication instead of /, url_for() properly handles that for you.
If you have elements like,meta, a navbar, etc in your base.html that you would like to display across all pages in your site. You can type this at the top of each new page.
{% extends "base.html" %}
{% block content %}
<!-- write page specific html between here -->
{% endblock %}
its important to place
{% block content %}
{% endblock %}
within you base.html file.
Related
I'm using auto generated HTML which has been saved to a file and then read in again to use as part of a page in a django template.
In order to do this I have used:
{% autoescape off %}
{{ my_html }}
{% endautoescape %}
However, in the my_html variable, I have some static content. This comes in the form of something like this:
<img src="{% static "img/tree_report.png" %}" width="12px" height="12px"/>
My issue is that the static content is not displayed. I get:
http://127.0.0.1:8000/%7B%%20static 404 (in the browser error report)
I read something about get_static_prefix in another question but that doesn't solve my problem because I just get this instead:
GET http://127.0.0.1:8000/%7B%%20get_static_prefix%20%%7Dimg/tree_report.png 404 (Not Found)
I also tried endautoscape turning on and off periodically in my_html in the saved HTML variable. That also didn't work.
Should I be autogenerating the development and production static files paths for my_html or is there a more elegant solution to this problem?
Any suggestions are most welcome.
Thanks.
I'm trying to learn Django at the moment and am trying to make sure I'm not doing anything stupid.
I'm in the process of making my web page more modular in the sense that I am removing hardcoded values in the template (base .html). Doing so, I'm trying to convert hardcoded CDN references (jquery, bootstrap, etc.) to modular pieces that can be included in every web page. Doing so will allow me to change a single file in the future, instead of being forced to go to every web page and make that change.
However, I'm slightly confused. I'm trying to determine if it would make sense to copy them into a html file and use Django's {% include '' %} template tag to directly include the cdn portions, or if using Django's static include would be more appropriate.
So what exactly is the best route? It seems like it would be very easy to use template includes for everything static in all honesty. Why not use it to include javascript or css?
Websites generally need to serve additional files such as images, JavaScript, or CSS. In Django, we refer to these files as “static files”.
We call them 'static' simply because they aren't dynamic i.e the contents of these files are relatively fixed, either by design or by it's intrinsic characteristics (eg: binary content like images) and thus does not need to processed by our application server.
We differentiate them from other files because it's advisable to serve these static files at a lower level, for example, using nginx. This allows us to serve these files faster as is which leads to performance gains. It also allows easy caching.
But when using a CDN, you offload this work from your server to somebody else's server.
Now coming back to your question. You shouldn't have to declare your resources in every template. Usually, base.html contains the base of the page which can then me extended (read: template inheritance) by more specific (children) templates.
To understand this quickly, here's an example:
base.html:
<html>
<head>
<meta charset="utf-8">
<link rel="stylesheet" href="~~CDN HERE~~">
<script src="~~CDN HERE~~"></script>
</head>
<body>
{% block body %}{% endblock %}
</body>
</html>
article.html
{% extends "app/base.html" %}
{% load static %}
{% block body %}
<h1>{{ page_title }}</h1>
<img src="{% static 'app/img/detective.png' %}" alt="detective" />
{{ page_content | safe }}
{% endblock %}
Now for every article on your site, you render the article template which automatically extends the base removing the need to mention your css/js files for multiple pages.
If you're using different resource files for different pages, you can creation an additional block like {% block css %}{% endblock %}
and then add this to your article.html
{% block css %}
<link rel="stylesheet" href="{% static 'app/css/article.css' %}">
{% endblock %}
Notice how I'm using static for image, which is served directly by nginx.
Theoretically, you can club your CDN links into a file and then include it in base.html, but it just leads over modularity which causes redundant complexity.
Let me know if you have any issues!
I am trying to use Django-Postman and have gotten as far as being able to see the templates on the webpage after I press the link but I don't know how send messages works. According to the write view there should be a form loaded but all I get is the links to the other pages in the template. If someone could explain how to get this to work it would be fantastic.
<div class="navbar-collapse collapse">
<ul class="nav navbar-nav ">
<li>MyCourse</li>
<li>Timetable</li>
<li>logout</li>
<li>Inbox</li>
</ul>
</div>
Recently had to set up postman myself, and based just off your snippet, I'm going to assume you wrote the ul element yourself.
So, if that's the case, postman actually expects to handle all of that for you. According to the docs, you need to create a base.html template inside your own template directory. A few blocks are expected to be present inside this template, namely {% title %} (text it will add to the page's title), {% extrahead %} (some extra js and css), {% content %} (would contain the missing forms you're looking for) and {% postman_menu %} (the menu links automatically generated by postman).
You could always create the menu links yourself, but I'd suggest you create a /postman folder in your app's template folder, then copy the base.html from the installed postman app (this contains the code for how to layout the ul). Just a little more django-esque, and usefull if you need to fiddle with the names of the template tags, etc, but that's up to you.
Hope this helps, happy coding.
In Django, when I use:
{{ request.build_absolute_uri }}{% static "img/myimage.jpg" %}
It produces: 'http://myurl.com//static/img/myimage.jpg'. This produces an error.
How can I remove the double slashes?
The STATIC URL is:
STATIC_URL = '/static/'
But I don't think removing the first '/' would be a good idea.
The request object is available within your templates and you can easily access attributes such as request.scheme or request.META.HTTP_HOST to construct your base URL that you can prepend ahead of your static URL to get the full URL.
Final example would look something like this:
<img src="{{request.scheme}}://{{request.META.HTTP_HOST}}{% static 'img/myimage.jpg' %}">
The build_absolute_uri method builds an absolute uri for the current page. That means that if you're on e.g. 'http://myurl.com/login/', the resulted full url would be 'http://myurl.com/login//static/img/myimage.jpg'.
Instead, use request.get_host() (optionally together with request.scheme for the url scheme), or preferably, use the sites framework to set a template variable to the current site domain. The get_host() method has some issues regarding proxies.
The get_host() method will return the current domain without a path appended.
I just made a quick template tag for doing this. Create files /myapp/templatetags/__init__.py and /myapp/templatetags/my_tag_library.py, if you don't have them already, and add the following to my_tag_library.py:
from django import template
from django.templatetags import static
register = template.Library()
class FullStaticNode(static.StaticNode):
def url(self, context):
request = context['request']
return request.build_absolute_uri(super().url(context))
#register.tag('fullstatic')
def do_static(parser, token):
return FullStaticNode.handle_token(parser, token)
Then in your templates, just {% load my_tag_library %} and use e.g. {% fullstatic my_image.jpg %}.
In response to earlier comments wondering why someone would need to do this, my particular use case was that I wanted to put a link to a static file inside of an open graph protocol meta tag, and those links need to be absolute. In development the static files get served locally, but in production they get served remotely, so I couldn't just prepend the host to get the full url.
Is this worth an update (Django 2+)?
This helped me specifically because I was trying to put a query in the link, i.e. the myimage.jpg was actually pulling from the DB. I needed a way to put it in the src, which was to replace 'myimage.jpg' with {{ img_link_field_in_model }}.
<img src="{% get_static_prefix %}img/myimage.jpg">
will produce:
<img src="/static/img/myimage.jpg">
The example of the query is:
<img src="{% get_static_prefix %}img/{{img_link_from_model}}">
Use this for apps:
{{ request.build_absolute_uri|slice:":-1" }}{% static "img/myimage.jpg" %}
Use this generally:
{{ request.scheme }}://{{ request.META.HTTP_HOST }}{% static "img/myimage.jpg" %}
Not entirely sure what you're asking, but since the {% static .. %} is only adding /static/ to the front of your path you specify, you could just do that yourself:
{{ request.build_absolute_uri }}static/img/myimage.jpg
Not very modular, but then again most times you don't need direct access to the full url since it will just append it onto whatever url you're at if you use it as a src for some html object.
build_absolute_uri takes the location as an argument which handles the double slash problem.
Unfortunately you cannot pass arguments via the django template language.
You will need to build a custom template tag or filter which accepts an argument to the build_absolute_uri function.
One of the many reasons I prefer Jinja as I can just do this:
{{ request.build_absolute_uri(static('img/foo.png')) }}
I have a comment_form.html template, which is used in multiple places in my app, and I'd like to be able to pass the endpoint's url into that template from a parent template. Normally I would do this using the with tag:
{% with endpoint='/comments' %}
{% include 'comment_form.html' %}
{% endwith %}
The problem is that I can't use a string literal '/comments' here, but instead I need a url tag, like so: {% url 'blog:comments:comments' username=post.user.username object_id=post.id %}. The with template tag seems to expects a literal or a context variable and doesn't seem to be able to comprehend "use the result of another template tag".
One solution would be to pass the strings 'blog:comments:comments', post.user.username, post.id all separately. But this is a problem because different uses of the comment form may require different arguments to uniquely define the endpoint.
How can I use with with the result of another template tag?
You can't, but you don't need to. The url tag has an alternative syntax that injects is result into the context:
{% url 'blog:comments:comments' username=post.user.username object_id=post.id as endpoint %}