Add optional url argument to didEncounterErrors hook (#242)

In previous versions of RESTDataSource, the URL of the request was
available on the Request object passed in to the hook. The Request
object is no longer passed as an argument, so this restores the
availability of the url to the hook.

This is optional for now in order to keep this change forward compatible
for existing this.didEncounterErrors call sites in userland code. In the
next major version, this might become a required parameter.

.changeset/gorgeous-timers-relax.md

@@ -0,0 +1,9 @@
+---
+'@apollo/datasource-rest': minor
+---
+
+Add optional `url` parameter to `didEncounterErrors` hook
+
+In previous versions of `RESTDataSource`, the URL of the request was available on the `Request` object passed in to the hook. The `Request` object is no longer passed as an argument, so this restores the availability of the `url` to the hook.
+
+This is optional for now in order to keep this change forward compatible for existing `this.didEncounterErrors` call sites in userland code. In the next major version, this might become a required parameter.

cspell-dict.txt

@@ -22,4 +22,5 @@ pino
 revalidates
 singletonizes
 unmock
+userland
 withrequired

src/RESTDataSource.ts

@@ -261,7 +261,12 @@ export abstract class RESTDataSource {
     request: FetcherRequestInit,
   ): ValueOrPromise<CacheOptions | undefined>;
 
-  protected didEncounterError(_error: Error, _request: RequestOptions) {
+  protected didEncounterError(
+    _error: Error,
+    _request: RequestOptions,
+    // TODO(v7): this shouldn't be optional in a future major version
+    _url?: URL,
+  ) {
     // left as a no-op instead of an unimplemented optional method to avoid
     // breaking an existing use case where one calls
     // `super.didEncounterErrors(...)` This could be unimplemented / undefined
@@ -544,7 +549,7 @@ export abstract class RESTDataSource {
             },
           };
         } catch (error) {
-          this.didEncounterError(error as Error, outgoingRequest);
+          this.didEncounterError(error as Error, outgoingRequest, url);
           throw error;
         }
       });

src/__tests__/RESTDataSource.test.ts

@@ -2193,6 +2193,43 @@ describe('RESTDataSource', () => {
             message: 'I replaced the error entirely',
           });
         });
+
+        it('is called with the url', async () => {
+          let urlFromDidEncounterError: URL | undefined = undefined;
+          const dataSource = new (class extends RESTDataSource {
+            override baseURL = 'https://api.example.com';
+
+            getFoo() {
+              return this.get('foo');
+            }
+
+            override didEncounterError(
+              _: Error,
+              __: RequestOptions,
+              url?: URL,
+            ) {
+              urlFromDidEncounterError = url;
+            }
+          })();
+
+          nock(apiUrl)
+            .get('/foo')
+            .reply(
+              500,
+              {
+                errors: [{ message: 'Houston, we have a problem.' }],
+              },
+              { 'content-type': 'application/json' },
+            );
+
+          try {
+            await dataSource.getFoo();
+          } catch {}
+
+          expect((urlFromDidEncounterError as any).toString()).toMatch(
+            'https://api.example.com/foo',
+          );
+        });
       });
     });
   });