pyramid_services_viewmapper

An extension for the Pyramid web framework.

pyramid_services_viewmapper provides a view mapper for use in conjunction with pyramid_services. It extends the functionality of pyramid_services to provide dependency injection: you can add custom arguments to your view functions, and the view mapper will automatically populate those arguments with matching services.

Setup

Register the view mapper in your Configurator:

from pyramid_services_viewmapper import ServiceViewMapper
config.set_view_mapper(ServiceViewMapper)

Usage

Services registered by interface alone are injected by a simple type annotation. For example this...

@view_config(route_name="home", renderer="json")
def home(request, login_svc: ILoginService):
    token = login_svc.create_token_for_login(name)
    return {"access_token": token}

...is equivalent to this:

@view_config(route_name="home", renderer="json")
def home(request):
    login_svc = request.find_service(ILoginService)
    token = login_svc.create_token_for_login(name)
    return {"access_token": token}

Services registered by name can be injected using a ServiceInjector object. For example this...

from pyramid_services_viewmapper import ServiceInjector as S

@view_config(route_name="users", renderer="json")
def users(request, db: S(name="db")):
    users = db.query(User)
    return {"users": users}

...is equivalent to this:

@view_config(route_name="users", renderer="json")
def users(request):
    db = request.find_service(name="db")
    users = db.query(User)
    return {"users": users}

The ServiceInjector class can be used as a shortcut for this:

from pyramid_services_viewmapper import ServiceInjector as S

@view_config(route_name="users", renderer="json")
def users(request, db: S):
    users = db.query(User)
    return {"users": users}