Python Pyramid - Route Prefix

Many times, similar URL patterns are registered with different routes in more than one Python code modules. For example, we have a student_routes.py where /pst and /add URL patterns are registered with pst and add routes. The view functions associated with these routes are pst() and add(), respectively.

#student_routes.py
from pyramid.config import Configurator
from pyramid.response import Response
from pyramid.view import view_config

@view_config( route_name= add )
def add(request):
   return Response( add student )
@view_config(route_name= pst )
def pst(request):
   return Response( Student pst )
   
def students(config):
   config.add_route( pst ,  /pst )
   config.add_route( add ,  /add )
   config.scan()

These routes will eventually be registered when the students() function is called.

At the same time, there is book_routes.py, in which the same URLs /pst and add/ are registered to show and new routes. Their associated views are pst() and add() respectively. The module has books() function which adds the routes.

#book_routes.py
from pyramid.config import Configurator
from pyramid.response import Response
from pyramid.view import view_config

@view_config( route_name= new )
def add(request):
   return Response( add book )
@view_config(route_name= show )
def pst(request):
   return Response( Book pst )
def books(config):
   config.add_route( show ,  /pst )
   config.add_route( new ,  /add )
   config.scan()

Obviously, there is a confpct between URL patterns as /pst and /add point to two routes each and this confpct must be resolved. This is done by using the route_prefix parameter of the config.include() method.

The first parameter to config.include() is the function which adds the routes, and the second is the route_prefix string which will be prepended to the URL pattern used in the included function.

Hence, the statement

config.include(students, route_prefix= /student )

will result in the /pst URL pattern changed to /student/pst and /add becomes student/add . Similarly, we can add prefix to these URL patterns in the books() function.

config.include(books, route_prefix= /books )

Example

The code that starts the server is as below −

from wsgiref.simple_server import make_server
from pyramid.config import Configurator
from pyramid.response import Response
from student_routes import students
from book_routes import books

if __name__ ==  __main__ :
   with Configurator() as config:
      config.include(students, route_prefix= /student )
      config.include(books, route_prefix= /book )
      app = config.make_wsgi_app()
   server = make_server( 0.0.0.0 , 6543, app)
   server.serve_forever()

Output

Let us run the above code and test the routes by following CURL commands.

C:UsersAcer>curl localhost:6543/student/pst
Student pst
C:UsersAcer>curl localhost:6543/student/add
add student
C:UsersAcer>curl localhost:6543/book/add
add book
C:UsersAcer>curl localhost:6543/book/pst
Book pst