feat: add qr code genartor api

app/api/v1/qr_generator.py

@@ -0,0 +1,99 @@
+from __future__ import annotations
+
+import threading
+from typing import Any, Dict, List, Optional
+
+from fastapi import APIRouter, HTTPException
+from pydantic import BaseModel, Field, field_validator
+
+from app.services.qr_generator_service import QRGeneratorService, QRGeneratorError
+
+router = APIRouter()
+
+_service_lock = threading.Lock()
+_shared_service: Optional[QRGeneratorService] = None
+
+
+def _get_service() -> QRGeneratorService:
+    global _shared_service
+    if _shared_service is None:
+        with _service_lock:
+            if _shared_service is None:
+                _shared_service = QRGeneratorService()
+    return _shared_service
+
+
+class QRGenerateRequest(BaseModel):
+    data: List[str] = Field(
+        ...,
+        min_length=1,
+        max_length=500,
+        description="List of data strings to generate QR codes for (max 500)",
+    )
+    size: str = Field(
+        "300x300",
+        description="QR code image size in WIDTHxHEIGHT format (e.g., 300x300)",
+    )
+
+    @field_validator("data")
+    @classmethod
+    def validate_data_items(cls, v: List[str]) -> List[str]:
+        for i, item in enumerate(v):
+            if not item or not item.strip():
+                raise ValueError(f"Data item at index {i} must be a non-empty string")
+            if len(item) > 2048:
+                raise ValueError(
+                    f"Data item at index {i} exceeds max length of 2048 characters"
+                )
+        return v
+
+    @field_validator("size")
+    @classmethod
+    def validate_size(cls, v: str) -> str:
+        parts = v.lower().split("x")
+        if len(parts) != 2:
+            raise ValueError("Size must be in format WIDTHxHEIGHT (e.g., 300x300)")
+        for part in parts:
+            if not part.isdigit() or int(part) < 1 or int(part) > 1000:
+                raise ValueError("Width and height must be between 1 and 1000")
+        return v
+
+
+class QRItemResult(BaseModel):
+    index: int
+    data: str
+    qr_image_url: Optional[str] = None
+    error: Optional[str] = None
+
+
+class QRGenerateResponse(BaseModel):
+    success: bool
+    total: int
+    succeeded: int
+    failed: int
+    results: List[QRItemResult]
+
+
+@router.post(
+    "/qr-generator",
+    response_model=QRGenerateResponse,
+    summary="Generate QR codes for a batch of data strings",
+    description="Accepts up to 500 data strings and returns QR code image URLs for each. "
+    "The actual QR image is hosted by an external service.",
+)
+def generate_qr_codes(body: QRGenerateRequest):
+    service = _get_service()
+    try:
+        results = service.generate_bulk(body.data, body.size)
+    except QRGeneratorError as e:
+        raise HTTPException(status_code=400, detail={"success": False, "error": str(e)})
+
+    succeeded = sum(1 for r in results if r["error"] is None)
+    failed = len(results) - succeeded
+    return QRGenerateResponse(
+        success=failed == 0,
+        total=len(results),
+        succeeded=succeeded,
+        failed=failed,
+        results=[QRItemResult(**r) for r in results],
+    )

app/api/v1/router.py

@@ -2,7 +2,7 @@ from __future__ import annotations
 
 from fastapi import APIRouter
 
-from app.api.v1 import auth, batch, chat, code_executor, convert, database, embeddings, reconcile, scraper, semantic_router, sql_validator, system, token_counter, token_generator, url_shortener, vector_stores, web_search, webhook_socket
+from app.api.v1 import auth, batch, chat, code_executor, convert, database, embeddings, qr_generator, reconcile, scraper, semantic_router, sql_validator, system, token_counter, token_generator, url_shortener, vector_stores, web_search, webhook_socket
 from app.api.verify import router as verify_router
 
 api_v1_router = APIRouter()
@@ -24,4 +24,5 @@ api_v1_router.include_router(token_generator.router, tags=["Token Generator"])
 api_v1_router.include_router(chat.router, tags=["Chat"])
 api_v1_router.include_router(vector_stores.router, tags=["Vector Stores"])
 api_v1_router.include_router(webhook_socket.router, tags=["Webhook / Socket"])
+api_v1_router.include_router(qr_generator.router, tags=["QR Generator"])
 api_v1_router.include_router(url_shortener.router, tags=["URL Shortener"])

app/services/qr_generator_service.py

@@ -0,0 +1,59 @@
+from __future__ import annotations
+
+import urllib.parse
+from typing import Any, Dict, List
+
+from app.core.logger import get_logger
+
+logger = get_logger(__name__)
+
+QR_CODE_BASE_URL = "https://api.qrserver.com/v1/create-qr-code/"
+DEFAULT_SIZE = "300x300"
+MAX_DATA_LENGTH = 2048
+MAX_ITEMS = 500
+
+
+class QRGeneratorError(Exception):
+    pass
+
+
+class QRGeneratorService:
+
+    def generate_bulk(
+        self,
+        data_list: List[str],
+        size: str = DEFAULT_SIZE,
+    ) -> List[Dict[str, Any]]:
+        results: List[Dict[str, Any]] = []
+        for idx, data in enumerate(data_list):
+            try:
+                self._validate_data(data)
+                qr_url = self._build_qr_url(data, size)
+                results.append({
+                    "index": idx,
+                    "data": data,
+                    "qr_image_url": qr_url,
+                    "error": None,
+                })
+            except QRGeneratorError as e:
+                results.append({
+                    "index": idx,
+                    "data": data,
+                    "qr_image_url": None,
+                    "error": str(e),
+                })
+        return results
+
+    @staticmethod
+    def _validate_data(data: str) -> None:
+        if not data or not isinstance(data, str):
+            raise QRGeneratorError("Data must be a non-empty string")
+        if len(data) > MAX_DATA_LENGTH:
+            raise QRGeneratorError(
+                f"Data exceeds max length of {MAX_DATA_LENGTH} characters"
+            )
+
+    @staticmethod
+    def _build_qr_url(data: str, size: str) -> str:
+        encoded = urllib.parse.quote(data, safe="")
+        return f"{QR_CODE_BASE_URL}?size={size}&data={encoded}"