feat: added Pagination info in the project summary (#959)

* feat: paginated summary of projects

* [pre-commit.ci] auto fixes from pre-commit.com hooks

for more information, see https://pre-commit.ci

---------

Co-authored-by: sujanadh <[email protected]>
Co-authored-by: pre-commit-ci[bot] <66853113+pre-commit-ci[bot]@users.noreply.github.com>

src/backend/app/projects/project_routes.py

@@ -109,12 +109,12 @@ def get_task(lat: float, long: float, user_id: int = None):
     return "Coming..."
 
 
-@router.get("/summaries", response_model=List[project_schemas.ProjectSummary])
+@router.get("/summaries", response_model=project_schemas.PaginatedProjectSummaries)
 async def read_project_summaries(
     user_id: int = None,
     hashtags: str = None,
-    skip: int = 0,
-    limit: int = 100,
+    page: int = Query(1, ge=1),  # Default to page 1, must be greater than or equal to 1
+    results_per_page: int = Query(13, le=100),
     db: Session = Depends(database.get_db),
 ):
     if hashtags:
@@ -123,8 +123,33 @@ async def read_project_summaries(
             filter(lambda hashtag: hashtag.startswith("#"), hashtags)
         )  # filter hashtags that do start with #
 
+    skip = (page - 1) * results_per_page
+    limit = results_per_page
+
+    total_projects = db.query(db_models.DbProject).count()
+    hasNext = (page * results_per_page) < total_projects
+    hasPrev = page > 1
+    total_pages = (total_projects + results_per_page - 1) // results_per_page
+
     projects = project_crud.get_project_summaries(db, user_id, skip, limit, hashtags)
-    return projects
+    project_summaries = [
+        project_schemas.ProjectSummary.from_db_project(project) for project in projects
+    ]
+
+    response = project_schemas.PaginatedProjectSummaries(
+        results=project_summaries,
+        pagination=project_schemas.PaginationInfo(
+            hasNext=hasNext,
+            hasPrev=hasPrev,
+            nextNum=page + 1 if hasNext else None,
+            page=page,
+            pages=total_pages,
+            prevNum=page - 1 if hasPrev else None,
+            perPage=results_per_page,
+            total=total_projects,
+        ),
+    )
+    return response
 
 
 @router.get("/{project_id}", response_model=project_schemas.ProjectOut)

src/backend/app/projects/project_schemas.py

@@ -21,6 +21,7 @@
 from geojson_pydantic import Feature as GeojsonFeature
 from pydantic import BaseModel
 
+from ..db import db_models
 from ..models.enums import ProjectPriority, ProjectStatus
 from ..tasks import tasks_schemas
 from ..users.user_schemas import User
@@ -76,6 +77,45 @@ class ProjectSummary(BaseModel):
     organisation_id: Optional[int] = None
     organisation_logo: Optional[str] = None
 
+    @classmethod
+    def from_db_project(
+        cls,
+        project: db_models.DbProject,
+    ) -> "ProjectSummary":
+        priority = project.priority
+        return cls(
+            id=project.id,
+            priority=priority,
+            priority_str=priority.name,
+            title=project.title,
+            location_str=project.location_str,
+            description=project.description,
+            total_tasks=project.total_tasks,
+            tasks_mapped=project.tasks_mapped,
+            num_contributors=project.num_contributors,
+            tasks_validated=project.tasks_validated,
+            tasks_bad=project.tasks_bad,
+            hashtags=project.hashtags,
+            organisation_id=project.organisation_id,
+            organisation_logo=project.organisation_logo,
+        )
+
+
+class PaginationInfo(BaseModel):
+    hasNext: bool
+    hasPrev: bool
+    nextNum: Optional[int]
+    page: int
+    pages: int
+    prevNum: Optional[int]
+    perPage: int
+    total: int
+
+
+class PaginatedProjectSummaries(BaseModel):
+    results: List[ProjectSummary]
+    pagination: PaginationInfo
+
 
 class ProjectBase(BaseModel):
     id: int