produces more informative errors for unsuccessful requests

tests/test_api_interface.py

@@ -7,11 +7,13 @@
 from urllib.parse import unquote
 from tempfile import gettempdir
 from os.path import join as path_join
+import re
 
 # 3rd party:
 
 # Internal: 
 from uk_covid19 import Cov19API
+from uk_covid19.exceptions import FailedRequestError
 
 # ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 
@@ -179,3 +181,26 @@ def test_length_equal(self):
 
         self.assertTrue(csv_len == json_len)
         self.assertTrue(csv_len == xml_len)
+
+    def test_unsuccessful_request(self):
+        bad_structure = {
+            "name": "areaName",
+            "date": "date",
+            # Missing the trailing "Date" - making the
+            # metric name invalid.
+            "newCases": "newCasesBySpecimen"
+        }
+
+        pattern = re.compile(r"404\s-\sNot Found.*'newCasesBySpecimenDate'", re.S | re.M)
+
+        api = Cov19API(filters=test_filters, structure=bad_structure)
+
+        with self.assertRaisesRegex(FailedRequestError, pattern):
+            api.get_json()
+
+        with self.assertRaisesRegex(FailedRequestError, pattern):
+            api.get_xml()
+
+        with self.assertRaisesRegex(FailedRequestError, pattern):
+            api.get_csv()
+

uk_covid19/__init__.py

@@ -33,7 +33,7 @@
 __copyright__ = "Copyright (c) 2020, Public Health England"
 __description__ = "SDK for the COVID-19 API (Coronavirus Dashboard in the UK)"
 __license__ = "MIT"
-__version__ = "1.1.4"
+__version__ = "1.1.5"
 __url__ = "https://coronavirus.data.gov.uk/"
 # ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 

uk_covid19/api_interface.py

@@ -15,6 +15,7 @@
 
 # Internal:
 from uk_covid19.utils import save_data
+from uk_covid19.exceptions import FailedRequestError
 
 # ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 
@@ -224,7 +225,8 @@ def _get(self, format_as: str) -> Iterator[Response]:
             with request("GET", self.endpoint, params=api_params,
                          verify=certifi.where()) as response:
                 if response.status_code >= HTTPStatus.BAD_REQUEST:
-                    raise RuntimeError(f'Request failed: {response.text}')
+                    raise FailedRequestError(response=response, params=api_params)
+
                 if response.status_code == HTTPStatus.NO_CONTENT:
                     self.total_pages = api_params["page"] - 1
                     break

uk_covid19/exceptions.py

@@ -0,0 +1,55 @@
+#!/usr/bin python3
+
+# Imports
+# ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+# Python:
+from pprint import pformat
+from urllib.parse import unquote
+
+# 3rd party:
+from requests import Response
+
+# Internal: 
+
+# ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+__all__ = [
+    'FailedRequestError'
+]
+
+
+class FailedRequestError(RuntimeError):
+    """
+    Exception for failed HTTP request.
+    """
+
+    message = """
+Request failed .... {status_code} - {reason}
+Response .......... {response_text}
+URL ............... {url}
+Decoded URL ........{decoded_url}
+Parameters:
+{params}
+"""
+
+    def __init__(self, response: Response, params: dict):
+        """
+        Parameters
+        ----------
+        response: Response
+            HTTP request ``Response`` object, as produced by the ``requests``
+            library.
+
+        params: dict
+            Dictionary of parameters.
+        """
+        message = self.message.format(
+            status_code=response.status_code,
+            reason=response.reason,
+            response_text=response.content.decode() or "No response",
+            url=response.url,
+            decoded_url=unquote(response.url),
+            params=pformat(params, indent=2)
+        )
+
+        super().__init__(message)