feat(ocr payment page) - added backend routes on app

apps/PaymentOCRService/main.py

@@ -0,0 +1,168 @@
+from fastapi import FastAPI, UploadFile, File, HTTPException, Request
+from fastapi.middleware.cors import CORSMiddleware
+from fastapi.responses import StreamingResponse, JSONResponse, PlainTextResponse
+from typing import List, Optional
+import io
+import os
+import asyncio
+
+from dotenv import load_dotenv
+load_dotenv()  # loads .env (GOOGLE_APPLICATION_CREDENTIALS, HOST, PORT, etc.)
+
+# Your adapter that calls the pipeline
+from complete_pipeline_adapter import process_images_to_rows,rows_to_csv_bytes
+
+# -------------------------------------------------
+# App + concurrency controls (similar to your other app)
+# -------------------------------------------------
+app = FastAPI(
+    title="Payment OCR Services API",
+    description="FastAPI wrapper around the OCR pipeline (Google Vision + deskew + line grouping + extraction).",
+    version="1.0.0",
+)
+
+# Concurrency/semaphore (optional but useful for OCR)
+MAX_CONCURRENCY = int(os.getenv("MAX_CONCURRENCY", "2"))
+semaphore = asyncio.Semaphore(MAX_CONCURRENCY)
+
+active_jobs = 0
+waiting_jobs = 0
+lock = asyncio.Lock()
+
+# CORS
+cors_origins = os.getenv("CORS_ORIGINS", "*")
+allow_origins = ["*"] if cors_origins.strip() == "*" else [o.strip() for o in cors_origins.split(",") if o.strip()]
+app.add_middleware(
+    CORSMiddleware,
+    allow_origins=allow_origins,
+    allow_methods=["*"],
+    allow_headers=["*"],
+)
+
+ALLOWED_EXTS = {".jpg", ".jpeg", ".png", ".tif", ".tiff", ".bmp"}
+
+# -------------------------------------------------
+# Health + status
+# -------------------------------------------------
+@app.get("/health", response_class=PlainTextResponse)
+def health():
+    creds = os.environ.get("GOOGLE_APPLICATION_CREDENTIALS", "")
+    return f"OK | GOOGLE_APPLICATION_CREDENTIALS set: {bool(creds)}"
+
+@app.get("/status")
+async def get_status():
+    async with lock:
+        return {
+            "active_jobs": active_jobs,
+            "queued_jobs": waiting_jobs,
+            "max_concurrency": MAX_CONCURRENCY,
+            "status": "busy" if active_jobs > 0 or waiting_jobs > 0 else "idle",
+        }
+
+# -------------------------------------------------
+# Helpers
+# -------------------------------------------------
+def _validate_files(files: List[UploadFile]):
+    if not files:
+        raise HTTPException(status_code=400, detail="No files provided.")
+    bad = [f.filename for f in files if os.path.splitext(f.filename or "")[1].lower() not in ALLOWED_EXTS]
+    if bad:
+        raise HTTPException(
+            status_code=415,
+            detail=f"Unsupported file types: {', '.join(bad)}. Allowed: {', '.join(sorted(ALLOWED_EXTS))}"
+        )
+
+# -------------------------------------------------
+# Endpoints
+# -------------------------------------------------
+@app.post("/extract/json")
+async def extract_json(files: List[UploadFile] = File(...)):
+    _validate_files(files)
+
+    async with lock:
+        global waiting_jobs
+        waiting_jobs += 1
+
+    async with semaphore:
+        async with lock:
+            waiting_jobs -= 1
+            global active_jobs
+            active_jobs += 1
+
+        try:
+            blobs = [await f.read() for f in files]
+            names = [f.filename or "upload.bin" for f in files]
+            rows = process_images_to_rows(blobs, names)  # calls your pipeline
+            return JSONResponse(content={"rows": rows})
+        except Exception as e:
+            raise HTTPException(status_code=500, detail=f"Processing error: {e}")
+        finally:
+            async with lock:
+                active_jobs -= 1
+
+@app.post("/extract/csvtext", response_class=PlainTextResponse)
+async def extract_csvtext(files: List[UploadFile] = File(...)):
+    _validate_files(files)
+
+    async with lock:
+        global waiting_jobs
+        waiting_jobs += 1
+
+    async with semaphore:
+        async with lock:
+            waiting_jobs -= 1
+            global active_jobs
+            active_jobs += 1
+
+        try:
+            blobs = [await f.read() for f in files]
+            names = [f.filename or "upload.bin" for f in files]
+            rows = process_images_to_rows(blobs, names)
+            csv_bytes = rows_to_csv_bytes(rows)
+            return PlainTextResponse(csv_bytes.decode("utf-8"), media_type="text/csv")
+        except Exception as e:
+            raise HTTPException(status_code=500, detail=f"Processing error: {e}")
+        finally:
+            async with lock:
+                active_jobs -= 1
+
+@app.post("/extract/csv")
+async def extract_csv(files: List[UploadFile] = File(...), filename: Optional[str] = None):
+    _validate_files(files)
+
+    async with lock:
+        global waiting_jobs
+        waiting_jobs += 1
+
+    async with semaphore:
+        async with lock:
+            waiting_jobs -= 1
+            global active_jobs
+            active_jobs += 1
+
+        try:
+            blobs = [await f.read() for f in files]
+            names = [f.filename or "upload.bin" for f in files]
+            rows = process_images_to_rows(blobs, names)
+            csv_bytes = rows_to_csv_bytes(rows)
+            out_name = filename or "medical_billing_extract.csv"
+            return StreamingResponse(
+                io.BytesIO(csv_bytes),
+                media_type="text/csv",
+                headers={"Content-Disposition": f'attachment; filename="{out_name}"'}
+            )
+        except Exception as e:
+            raise HTTPException(status_code=500, detail=f"Processing error: {e}")
+        finally:
+            async with lock:
+                active_jobs -= 1
+
+# -------------------------------------------------
+# Entrypoint (same pattern as your selenium app)
+# -------------------------------------------------
+if __name__ == "__main__":
+    import uvicorn
+    host = os.getenv("HOST")
+    port = int(os.getenv("PORT"))
+    reload_flag = os.getenv("RELOAD", "false").lower() == "true"
+    uvicorn.run(app, host=host, port=port, reload=reload_flag)