Add third parameter with response to trace and allow it to be asynchr…

…onous (#53)

README.md

@@ -408,8 +408,11 @@ await enhancedFetch("https://example.com/api/users/:role", {
 // method: 'POST',
 // body: '{"some":{"object":{"as":{"body":{}}}}}',
 // }
+// Response {}
 ```
 
+The `trace` function can also return a `Promise<void>` in order to send traces to an external service or database.
+
 ## typedResponse
 
 A type-safe wrapper around the `Response` object. It adds a `json` and `text` method that will parse the response with a given zod schema. If you don't provide a schema, it will return `unknown` instead of `any`, then you can also give it a generic to type cast the result.

src/api.test.ts

@@ -198,6 +198,7 @@ describe('enhancedFetch', () => {
  method: 'POST',
  body: `{"id":1,"name":{"first":"John","last":"Doe"}}`,
  },
+ expect.any(Response),
  )
  })
 
@@ -358,6 +359,7 @@ describe('makeFetcher', () => {
  body: `{"id":1,"name":{"first":"John","last":"Doe"}}`,
  headers: new Headers(),
  },
+ expect.any(Response),
  )
  })
 })

src/api.ts

@@ -67,7 +67,7 @@ function typedResponse(
  * @param requestInit the requestInit to be passed to the fetch request. It is the same as the `RequestInit` type, but it also accepts a JSON-like `body` and an object-like `query` parameter.
  * @param requestInit.body the body of the request. It will be automatically stringified so you can send a JSON-like object
  * @param requestInit.query the query parameters to be added to the URL
- * @param requestInit.trace a function that receives the URL and the requestInit and can be used to log the request
+ * @param requestInit.trace a function that receives the URL, the requestInit and a clone of the response in order to log or troubleshoot the request
  * @returns a Response with typed json and text methods
  * @example const response = await fetch("https://example.com/api/users");
  * const users = await response.json(userSchema);
@@ -83,11 +83,11 @@ async function enhancedFetch<T extends string | URL>(
  const body = ensureStringBody(reqInit.body)
  const withParams = replaceURLParams<T>(url, reqInit.params ?? ({} as never))
  const fullURL = addQueryToURL(withParams, query)
-
  const enhancedReqInit = { ...reqInit, body }
- trace?.(fullURL, enhancedReqInit)
+
  const response = await fetch(fullURL, enhancedReqInit)
 
+ await trace?.(fullURL, enhancedReqInit, typedResponse(response.clone()))
  return typedResponse(response)
 }
 

src/types.ts

@@ -28,7 +28,11 @@ type EnhancedRequestInit<T = string> = Omit<RequestInit, 'body' | 'method'> & {
  body?: JSONValue | BodyInit | null
  query?: SearchParams
  params?: PathParams<T>
- trace?: (...args: Parameters<typeof fetch>) => void
+ trace?: (
+ fullUrl: string | URL,
+ init: EnhancedRequestInit,
+ response: TypedResponse,
+ ) => void | Promise<void>
 }
 
 type ServiceRequestInit<T = string> = Omit<EnhancedRequestInit<T>, 'method'>