ch14

ch14/apic/rails/views.py

@@ -0,0 +1,169 @@
+# apic/rails/views.py
+from datetime import datetime
+from operator import itemgetter
+from urllib.parse import urljoin
+
+import requests
+from django.conf import settings
+from django.urls import reverse_lazy
+from django.views import generic
+from requests.exceptions import RequestException
+
+from .forms import AuthenticateForm
+
+
+class IndexView(generic.TemplateView):
+    template_name = "rails/index.html"
+
+
+class StationsView(generic.TemplateView):
+    template_name = "rails/stations.html"
+
+    def get(self, request, *args, **kwargs):
+        context = self.get_context_data(**kwargs)
+
+        api_url = urljoin(settings.BASE_API_URL, "stations")
+
+        try:
+            response = requests.get(api_url)
+            response.raise_for_status()
+        except RequestException as err:
+            context["error"] = err
+        else:
+            context["stations"] = response.json()
+
+        return self.render_to_response(context)
+
+
+class DeparturesView(generic.TemplateView):
+    template_name = "rails/departures.html"
+
+    def get(self, request, station_id, *args, **kwargs):
+        context = self.get_context_data(**kwargs)
+
+        api_url = urljoin(
+            settings.BASE_API_URL,
+            f"stations/{station_id}/departures",
+        )
+
+        try:
+            response = requests.get(api_url)
+            response.raise_for_status()
+        except RequestException as err:
+            context["error"] = err
+        else:
+            trains = prepare_trains(response.json(), "departs_at")
+            context["departures"] = trains
+
+        return self.render_to_response(context)
+
+
+class ArrivalsView(generic.TemplateView):
+    template_name = "rails/arrivals.html"
+
+    def get(self, request, station_id, *args, **kwargs):
+        context = self.get_context_data(**kwargs)
+
+        api_url = urljoin(
+            settings.BASE_API_URL,
+            f"stations/{station_id}/arrivals",
+        )
+
+        try:
+            response = requests.get(api_url)
+            response.raise_for_status()
+        except RequestException as err:
+            context["error"] = err
+        else:
+            trains = prepare_trains(response.json(), "arrives_at")
+            context["arrivals"] = trains
+
+        return self.render_to_response(context)
+
+
+class UsersView(generic.TemplateView):
+    template_name = "rails/users.html"
+
+    def get(self, request, *args, **kwargs):
+        context = self.get_context_data(**kwargs)
+
+        api_url = urljoin(
+            settings.BASE_API_URL,
+            "users",
+        )
+
+        try:
+            response = requests.get(api_url)
+            response.raise_for_status()
+        except RequestException as err:
+            context["error"] = err
+        else:
+            context["users"] = response.json()
+
+        return self.render_to_response(context)
+
+
+class AuthenticateView(generic.FormView):
+    template_name = "rails/authenticate.html"
+    success_url = reverse_lazy("auth_result")
+    form_class = AuthenticateForm
+
+    def form_valid(self, form):
+        data = form.cleaned_data
+        self.api_authenticate(data["email"], data["password"])
+        # leave this as final instruction as it will just perform the redir.
+        return super().form_valid(form)
+
+    def api_authenticate(self, email, password):
+        api_url = urljoin(
+            settings.BASE_API_URL,
+            f"users/authenticate",
+        )
+
+        payload = {
+            "email": email,
+            "password": password,
+        }
+
+        try:
+            response = requests.post(api_url, json=payload)
+            response.raise_for_status()
+        except RequestException as err:
+            self.set_session_data("auth_error", str(err))
+        else:
+            key = "token" if response.ok else "auth_error"
+            self.set_session_data(key, response.json())
+
+    def set_session_data(self, key, data):
+        self.request.session[key] = data
+
+
+class AuthenticateResultView(generic.TemplateView):
+    template_name = "rails/authenticate.result.html"
+
+    def get(self, request, *args, **kwargs):
+        context = self.get_context_data(**kwargs)
+        context["token"] = request.session.pop("token", None)
+        context["auth_error"] = request.session.pop(
+            "auth_error", None
+        )
+        return self.render_to_response(context)
+
+
+def prepare_trains(trains: list[dict], key: str):
+    return list(
+        map(
+            parse_datetimes,
+            sorted(trains, key=itemgetter(key)),
+        )
+    )
+
+
+def parse_datetimes(train: dict):
+    train["arrives_at"] = datetime.fromisoformat(
+        train["arrives_at"]
+    )
+    train["departs_at"] = datetime.fromisoformat(
+        train["departs_at"]
+    )
+    return train