F(backend): add public media derivatives pipeline

apps/blog/api/schemas.py

@@ -5,6 +5,7 @@ from typing import Optional, List
 from datetime import datetime
 
 from apps.blog.models import Category, Tag, Comment
+from core.media import PREVIEW_VARIANT, THUMBNAIL_VARIANT, derivative_url
 
 
 class CategorySchema(ModelSchema):
@@ -23,6 +24,8 @@ class AuthorSchema(Schema):
     first_name: str
     last_name: str
     profile_picture: Optional[str] = None
+    profile_picture_thumbnail_url: Optional[str] = None
+    profile_picture_preview_url: Optional[str] = None
 
     @staticmethod
     def resolve_profile_picture(obj, context):
@@ -31,6 +34,18 @@ class AuthorSchema(Schema):
             return request.build_absolute_uri(obj.profile_picture.url)
         return None
 
+    @staticmethod
+    def resolve_profile_picture_thumbnail_url(obj, context):
+        request = context["request"]
+        url = derivative_url(obj.profile_picture, THUMBNAIL_VARIANT)
+        return request.build_absolute_uri(url) if url else None
+
+    @staticmethod
+    def resolve_profile_picture_preview_url(obj, context):
+        request = context["request"]
+        url = derivative_url(obj.profile_picture, PREVIEW_VARIANT)
+        return request.build_absolute_uri(url) if url else None
+
 class PostListSchema(Schema):
     id: int
     title: str
@@ -38,6 +53,9 @@ class PostListSchema(Schema):
     excerpt: str
     author: AuthorSchema
     featured_image: Optional[str] = None
+    absolute_featured_image_url: Optional[str] = None
+    absolute_featured_image_thumbnail_url: Optional[str] = None
+    absolute_featured_image_preview_url: Optional[str] = None
     status: str
     published_at: Optional[datetime] = None
     category: Optional[CategorySchema] = None
@@ -46,6 +64,25 @@ class PostListSchema(Schema):
     created_at: datetime
     reading_time: int
 
+    @staticmethod
+    def resolve_absolute_featured_image_url(obj, context):
+        request = context["request"]
+        if obj.featured_image and hasattr(obj.featured_image, "url"):
+            return request.build_absolute_uri(obj.featured_image.url)
+        return None
+
+    @staticmethod
+    def resolve_absolute_featured_image_thumbnail_url(obj, context):
+        request = context["request"]
+        url = derivative_url(obj.featured_image, THUMBNAIL_VARIANT)
+        return request.build_absolute_uri(url) if url else None
+
+    @staticmethod
+    def resolve_absolute_featured_image_preview_url(obj, context):
+        request = context["request"]
+        url = derivative_url(obj.featured_image, PREVIEW_VARIANT)
+        return request.build_absolute_uri(url) if url else None
+
 class PostDetailSchema(PostListSchema):
     content: str
     content_html: str