Implement WrapperHandler for managing multiple news API wrappers; add tests for wrapper functionality

src/app/news/__init__.py

@@ -1,5 +1,18 @@
+from app.utils.wrapper_handler import WrapperHandler
+from .base import NewsWrapper, Article
 from .news_api import NewsApiWrapper
 from .gnews_api import GnewsWrapper
 from .cryptopanic_api import CryptoPanicWrapper
 
-__all__ = ["NewsApiWrapper", "GnewsWrapper", "CryptoPanicWrapper"]
+__all__ = ["NewsApiWrapper", "GnewsWrapper", "CryptoPanicWrapper"]
+
+
+class NewsAPIs(NewsWrapper):
+    def __init__(self):
+        wrappers = [GnewsWrapper, NewsApiWrapper, CryptoPanicWrapper]
+        self.wrapper_handler: WrapperHandler[NewsWrapper] = WrapperHandler.build_wrappers(wrappers)
+
+    def get_top_headlines(self, query: str, total: int = 100) -> list[Article]:
+        return self.wrapper_handler.try_call(lambda w: w.get_top_headlines(query, total))
+    def get_latest_news(self, query: str, total: int = 100) -> list[Article]:
+        return self.wrapper_handler.try_call(lambda w: w.get_latest_news(query, total))

src/app/utils/wrapper_handler.py

@@ -0,0 +1,48 @@
+import time
+from typing import TypeVar, Callable, Generic, Iterable, Type
+from agno.utils.log import log_warning
+
+W = TypeVar("W")
+T = TypeVar("T")
+
+class WrapperHandler(Generic[W]):
+    def __init__(self, wrappers: list[W], try_per_wrapper: int = 3, retry_delay: int = 2):
+        self.wrappers = wrappers
+        self.retry_per_wrapper = try_per_wrapper
+        self.retry_delay = retry_delay
+        self.index = 0
+        self.retry_count = 0
+
+    def try_call(self, func: Callable[[W], T]) -> T:
+        iterations = 0
+        while iterations < len(self.wrappers):
+            print(f"Trying wrapper {self.index}")
+            try:
+                wrapper = self.wrappers[self.index]
+                result = func(wrapper)
+                self.retry_count = 0
+                return result
+            except Exception as e:
+                self.retry_count += 1
+                print(f"Error occurred {self.retry_count}/{self.retry_per_wrapper}: {e}")
+                if self.retry_count >= self.retry_per_wrapper:
+                    self.index = (self.index + 1) % len(self.wrappers)
+                    self.retry_count = 0
+                    iterations += 1
+                else:
+                    log_warning(f"{wrapper} failed {self.retry_count}/{self.retry_per_wrapper}: {e}")
+                    time.sleep(self.retry_delay)
+
+        raise Exception(f"All wrappers failed after retries")
+
+    @staticmethod
+    def build_wrappers(constructors: Iterable[Type[W]], try_per_wrapper: int = 3, retry_delay: int = 2) -> 'WrapperHandler[W]':
+        result = []
+        for wrapper_class in constructors:
+            try:
+                wrapper = wrapper_class()
+                result.append(wrapper)
+            except Exception as e:
+                log_warning(f"{wrapper_class} cannot be initialized: {e}")
+
+        return WrapperHandler(result, try_per_wrapper, retry_delay)