Create dynamic URLs in Flask with url_for()
Question:
Half of my Flask routes requires a variable say, /<variable>/add or /<variable>/remove. How do I create links to those locations?
url_for() takes one argument for the function to route to but I can’t add arguments?
Answers:
It takes keyword arguments for the variables:
url_for('add', variable=foo)
url_for('remove', variable=foo)
The flask-server would have functions:
@app.route('/<variable>/add', methods=['GET', 'POST'])
def add(variable):
@app.route('/<variable>/remove', methods=['GET', 'POST'])
def remove(variable):
Refer to the Flask API document for flask.url_for()
Other sample snippets of usage for linking js or css to your template are below.
<script src="{{ url_for('static', filename='jquery.min.js') }}"></script>
<link rel=stylesheet type=text/css href="{{ url_for('static', filename='style.css') }}">
url_for in Flask is used for creating a URL to prevent the overhead of having to change URLs throughout an application (including in templates). Without url_for, if there is a change in the root URL of your app then you have to change it in every page where the link is present.
Syntax: url_for('name of the function of the route','parameters (if required)')
It can be used as:
@app.route('/index')
@app.route('/')
def index():
return 'you are in the index page'
Now if you have a link the index page:you can use this:
<a href={{ url_for('index') }}>Index</a>
You can do a lot o stuff with it, for example:
@app.route('/questions/<int:question_id>') #int has been used as a filter that only integer will be passed in the url otherwise it will give a 404 error
def find_question(question_id):
return ('you asked for question{0}'.format(question_id))
For the above we can use:
<a href = {{ url_for('find_question' ,question_id=1) }}>Question 1</a>
Like this you can simply pass the parameters!
Templates:
Pass function name and argument.
<a href="{{ url_for('get_blog_post',id = blog.id)}}">{{blog.title}}</a>
View,function
@app.route('/blog/post/<string:id>',methods=['GET'])
def get_blog_post(id):
return id
You need to add function means that the page you want to render that function whould be added inside the url_for(function name).
It will redirect to that function and the page will render accordingly.
Half of my Flask routes requires a variable say, /<variable>/add or /<variable>/remove. How do I create links to those locations?
url_for() takes one argument for the function to route to but I can’t add arguments?
It takes keyword arguments for the variables:
url_for('add', variable=foo)
url_for('remove', variable=foo)
The flask-server would have functions:
@app.route('/<variable>/add', methods=['GET', 'POST'])
def add(variable):
@app.route('/<variable>/remove', methods=['GET', 'POST'])
def remove(variable):
Refer to the Flask API document for flask.url_for()
Other sample snippets of usage for linking js or css to your template are below.
<script src="{{ url_for('static', filename='jquery.min.js') }}"></script>
<link rel=stylesheet type=text/css href="{{ url_for('static', filename='style.css') }}">
url_for in Flask is used for creating a URL to prevent the overhead of having to change URLs throughout an application (including in templates). Without url_for, if there is a change in the root URL of your app then you have to change it in every page where the link is present.
Syntax: url_for('name of the function of the route','parameters (if required)')
It can be used as:
@app.route('/index')
@app.route('/')
def index():
return 'you are in the index page'
Now if you have a link the index page:you can use this:
<a href={{ url_for('index') }}>Index</a>
You can do a lot o stuff with it, for example:
@app.route('/questions/<int:question_id>') #int has been used as a filter that only integer will be passed in the url otherwise it will give a 404 error
def find_question(question_id):
return ('you asked for question{0}'.format(question_id))
For the above we can use:
<a href = {{ url_for('find_question' ,question_id=1) }}>Question 1</a>
Like this you can simply pass the parameters!
Templates:
Pass function name and argument.
<a href="{{ url_for('get_blog_post',id = blog.id)}}">{{blog.title}}</a>
View,function
@app.route('/blog/post/<string:id>',methods=['GET'])
def get_blog_post(id):
return id
You need to add function means that the page you want to render that function whould be added inside the url_for(function name).
It will redirect to that function and the page will render accordingly.