Added posts creation and posts detail

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