Added posts creation and posts detail

solution/pulse/api/posts/apps.py

@@ -0,0 +1,6 @@
+from django.apps import AppConfig
+
+
+class PostsConfig(AppConfig):
+    default_auto_field = "django.db.models.BigAutoField"
+    name = "api.posts"

solution/pulse/api/posts/migrations/0001_initial.py

@@ -0,0 +1,29 @@
+# Generated by Django 4.2.10 on 2024-03-03 17:48
+
+from django.db import migrations, models
+import django.db.models.deletion
+import uuid
+
+
+class Migration(migrations.Migration):
+
+    initial = True
+
+    dependencies = [
+        ('users', '0001_initial'),
+    ]
+
+    operations = [
+        migrations.CreateModel(
+            name='Post',
+            fields=[
+                ('id', models.UUIDField(default=uuid.uuid4, primary_key=True, serialize=False)),
+                ('content', models.TextField(max_length=1000)),
+                ('tags', models.JSONField()),
+                ('createdAt', models.DateTimeField(auto_now_add=True)),
+                ('author', models.ForeignKey(on_delete=django.db.models.deletion.CASCADE, related_name='posts', to='users.profile')),
+                ('dislikes', models.ManyToManyField(blank=True, related_name='disliked_posts', to='users.profile')),
+                ('likes', models.ManyToManyField(blank=True, related_name='liked_posts', to='users.profile')),
+            ],
+        ),
+    ]

solution/pulse/api/posts/models.py

@@ -0,0 +1,27 @@
+import uuid
+
+from django.db import models
+
+from api.users.models import Profile
+
+
+class Post(models.Model):
+    id = models.UUIDField(primary_key=True, default=uuid.uuid4)
+    content = models.TextField(max_length=1000)
+    author = models.ForeignKey(
+        Profile,
+        on_delete=models.CASCADE,
+        related_name="posts",
+    )
+    tags = models.JSONField()
+    # ruff: noqa: N815
+    createdAt = models.DateTimeField(auto_now_add=True)
+    likes = models.ManyToManyField(
+        Profile, related_name="liked_posts", blank=True
+    )
+    dislikes = models.ManyToManyField(
+        Profile, related_name="disliked_posts", blank=True
+    )
+
+    def __str__(self):
+        return self.content

solution/pulse/api/posts/permissions.py

@@ -0,0 +1,17 @@
+from rest_framework import status
+from rest_framework.permissions import BasePermission
+
+
+class CanAccessPost(BasePermission):
+    message = "You do not have permission to access this post."
+    status_code = status.HTTP_404_NOT_FOUND
+
+    def has_object_permission(self, request, view, obj):
+        if (
+            obj.author.isPublic
+            or obj.author.check_for_friendship(request.user)
+            or obj.author == request.user
+        ):
+            return True
+
+        return False

solution/pulse/api/posts/serializers.py

@@ -0,0 +1,38 @@
+from django.conf import settings
+from rest_framework import serializers
+
+from api.posts.models import Post
+
+
+class PostSerializer(serializers.ModelSerializer):
+    # ruff: noqa: N815
+    author = serializers.ReadOnlyField(source="author.username")
+    likesCount = serializers.SerializerMethodField()
+    dislikesCount = serializers.SerializerMethodField()
+
+    class Meta:
+        model = Post
+        fields = [
+            "id",
+            "content",
+            "author",
+            "tags",
+            "createdAt",
+            "likesCount",
+            "dislikesCount",
+        ]
+        read_only_fields = ["id", "createdAt", "likesCount", "dislikesCount"]
+
+    # ruff: noqa: N802
+    def get_likesCount(self, obj):
+        return obj.likes.count()
+
+    def get_dislikesCount(self, obj):
+        return obj.dislikes.count()
+
+    def validate_tags(self, value):
+        for tag in value:
+            if len(tag) > settings.MAX_TAG_LENGTH:
+                error = "Each tag must be 20 characters or fewer."
+                raise serializers.ValidationError(error)
+        return value

solution/pulse/api/posts/urls.py

@@ -0,0 +1,16 @@
+from django.urls import path
+
+import api.posts.views
+
+urlpatterns = [
+    path(
+        "/create",
+        api.posts.views.CreatePostApiView.as_view(),
+        name="create-post",
+    ),
+    path(
+        "/<str:post_id>",
+        api.posts.views.PostDetailApiView.as_view(),
+        name="post-detail",
+    ),
+]

solution/pulse/api/posts/views.py

@@ -0,0 +1,35 @@
+from rest_framework import status
+from rest_framework.exceptions import NotFound, ValidationError
+from rest_framework.permissions import IsAuthenticated
+from rest_framework.response import Response
+from rest_framework.views import APIView
+
+from api.posts.models import Post
+from api.posts.permissions import CanAccessPost
+from api.posts.serializers import PostSerializer
+
+
+class CreatePostApiView(APIView):
+    permission_classes = [IsAuthenticated]
+
+    def post(self, request):
+        serializer = PostSerializer(data=request.data)
+        if serializer.is_valid():
+            serializer.save(author=request.user)
+            return Response(serializer.data, status=status.HTTP_201_CREATED)
+        raise ValidationError(serializer.errors)
+
+
+class PostDetailApiView(APIView):
+    permission_classes = [IsAuthenticated, CanAccessPost]
+
+    def get(self, request, post_id):
+        try:
+            post = Post.objects.get(id=post_id)
+            self.check_object_permissions(request, post)
+            serializer = PostSerializer(post)
+            return Response(serializer.data)
+        except Post.DoesNotExist:
+            raise NotFound(
+                {"detail": "Post not found."},
+            ) from None

solution/pulse/api/urls.py

@@ -3,5 +3,6 @@ from django.urls import include, path
 urlpatterns = [
     path("ping", include("api.ping.urls")),
     path("countries", include("api.countries.urls")),
+    path("posts", include("api.posts.urls")),
     path("", include("api.users.urls")),
 ]

solution/pulse/api/users/models.py

@@ -51,6 +51,14 @@ class Profile(models.Model):
     def check_for_friendship(self, user):
         return self.friends.filter(pk=user.pk).exists()
 
+    def like_post(self, post):
+        self.disliked_posts.remove(post)
+        return self.liked_posts.add(post)
+
+    def dislike_post(self, post):
+        self.liked_posts.remove(post)
+        return self.disliked_posts.add(post)
+
     @classmethod
     def check_unique(cls, user_id, validated_data):
         errors = {}

solution/pulse/pulse/settings.py

@@ -29,6 +29,7 @@ INSTALLED_APPS = [
     "api.ping.apps.PingConfig",
     "api.countries.apps.CountriesConfig",
     "api.users.apps.UsersConfig",
+    "api.posts.apps.PostsConfig",
 ]
 
 MIDDLEWARE = [
@@ -124,6 +125,8 @@ REST_FRAMEWORK = {
 
 APPEND_SLASH = False
 
+MAX_TAG_LENGTH = 20
+
 if DEBUG:
     INSTALLED_APPS.insert(0, "debug_toolbar")
     MIDDLEWARE.append("debug_toolbar.middleware.DebugToolbarMiddleware")