feat: Implement pagination for companies, investors, and projects endpoints

app/routers/companies.py

@@ -1,10 +1,10 @@
-from typing import List, Optional
+from typing import Optional
 
 from db.db import get_db
 from db.models import CompanyTable, InvestorTable
 from fastapi import APIRouter, Depends, HTTPException, Query
 from pydantic import BaseModel
-from schemas.router_schemas import CompanyData
+from schemas.router_schemas import CompanyData, PaginatedResponse
 from sqlalchemy.orm import Session, selectinload
 
 router = APIRouter(tags=["Company Routes"])
@@ -29,20 +29,34 @@ class CompanyUpdate(BaseModel):
     website: Optional[str] = None
 
 
-@router.get("/companies", response_model=List[CompanyData])
-def read_companies(db: Session = Depends(get_db)):
-    """Get all companies with their investor relationships"""
+@router.get("/companies", response_model=PaginatedResponse[CompanyData])
+def read_companies(
+    page: int = Query(1, ge=1, description="Page number (starts at 1)"),
+    page_size: int = Query(10, ge=1, le=100, description="Items per page (max 100)"),
+    db: Session = Depends(get_db),
+):
+    """Get all companies with their investor relationships (paginated)"""
+    # Calculate offset
+    offset = (page - 1) * page_size
+
+    # Get total count
+    total_count = (
+        db.query(CompanyTable)
+        .filter(CompanyTable.name.isnot(None), CompanyTable.description.isnot(None))
+        .count()
+    )
+
+    # Get paginated results
     companies = (
         db.query(CompanyTable)
-        .filter(
-            CompanyTable.name.isnot(None),
-            CompanyTable.description.isnot(None)
-        )
+        .filter(CompanyTable.name.isnot(None), CompanyTable.description.isnot(None))
         .options(
             selectinload(CompanyTable.investors),
             selectinload(CompanyTable.members),
             selectinload(CompanyTable.sectors),
         )
+        .offset(offset)
+        .limit(page_size)
         .all()
     )
 
@@ -57,10 +71,19 @@ def read_companies(db: Session = Depends(get_db)):
         )
         company_data_list.append(company_data)
 
-    return company_data_list
+    # Calculate total pages
+    total_pages = (total_count + page_size - 1) // page_size
+
+    return PaginatedResponse(
+        items=company_data_list,
+        total=total_count,
+        page=page,
+        page_size=page_size,
+        total_pages=total_pages,
+    )
 
 
-@router.get("/companies/filter", response_model=List[CompanyData])
+@router.get("/companies/filter", response_model=PaginatedResponse[CompanyData])
 def filter_companies(
     industry: Optional[str] = Query(
         None, description="Filter by industry (partial match)"
@@ -76,9 +99,11 @@ def filter_companies(
     investor_name: Optional[str] = Query(
         None, description="Filter by investor name (partial match)"
     ),
+    page: int = Query(1, ge=1, description="Page number (starts at 1)"),
+    page_size: int = Query(10, ge=1, le=100, description="Items per page (max 100)"),
     db: Session = Depends(get_db),
 ):
-    """Filter companies based on various criteria"""
+    """Filter companies based on various criteria (paginated)"""
 
     # Start with base query
     query = db.query(CompanyTable).options(
@@ -112,7 +137,12 @@ def filter_companies(
             InvestorTable.name.ilike(f"%{investor_name}%")
         )
 
-    companies = query.all()
+    # Get total count before pagination
+    total_count = query.count()
+
+    # Calculate offset and apply pagination
+    offset = (page - 1) * page_size
+    companies = query.offset(offset).limit(page_size).all()
 
     # Transform to CompanyData format
     company_data_list = []
@@ -125,7 +155,16 @@ def filter_companies(
         )
         company_data_list.append(company_data)
 
-    return company_data_list
+    # Calculate total pages
+    total_pages = (total_count + page_size - 1) // page_size
+
+    return PaginatedResponse(
+        items=company_data_list,
+        total=total_count,
+        page=page,
+        page_size=page_size,
+        total_pages=total_pages,
+    )
 
 
 @router.get("/companies/{company_id}", response_model=CompanyData)