Add error handling for json parsing to UPRN client (#2992)

* Add error handling for JSON parsing in UPRN client

* Update error handling

* Update error handling 2

* Updates with sentry error reporting and test

* Add rails logger message as well as sentry

app/services/uprn_client.rb

@@ -24,7 +24,9 @@ class UprnClient
                   parsed_response = JSON.parse(response.body)
                   parsed_response.dig("results", 0, "DPA") || parsed_response.dig("results", 0, "LPI")
                 else
-                  Rails.logger.error("Response code: #{response.code}")
+                  @error = "UPRN client failed to return a valid result, try again later."
+                  Sentry.capture_message("UPRN client failed to return a valid result with error code: #{response.code}.")
+                  Rails.logger.error("UPRN client failed to return a valid result with error code: #{response.code}.")
                   Rails.logger.error("Response body: #{response.body}")
                   nil
                 end

spec/services/uprn_client_spec.rb

@@ -86,5 +86,33 @@ describe UprnClient do
         expect(client.error).to be_nil
       end
     end
+
+    describe "result" do
+      context "when response is successful" do
+        before do
+          stub_api_request(body: valid_response)
+
+          client.call
+        end
+
+        it "returns parsed result" do
+          expect(client.result).to eq({ "postcode" => "12345" })
+          expect(client.send(:response).code.to_i).to eq(200)
+        end
+      end
+
+      context "when response is not successful" do
+        before do
+          stub_api_request(body: valid_response, status: 500)
+
+          client.call
+        end
+
+        it "returns nil" do
+          expect(client.result).to be_nil
+          expect(client.error).to eq("UPRN client failed to return a valid result, try again later.")
+        end
+      end
+    end
   end
 end