refactor: use fetch cache arg instead of cache busting (#3584)

packages/netlify-cms-lib-util/src/API.ts

@@ -119,19 +119,21 @@ export type FileMetadata = {
 const getFileMetadataKey = (id: string) => `gh.${id}.meta`;
 
 export const readFileMetadata = async (
-  id: string,
+  id: string | null | undefined,
   fetchMetadata: () => Promise<FileMetadata>,
   localForage: LocalForage,
 ) => {
-  const key = getFileMetadataKey(id);
-  const cached = await localForage.getItem<FileMetadata>(key);
+  const key = id ? getFileMetadataKey(id) : null;
+  const cached = key && (await localForage.getItem<FileMetadata>(key));
   if (cached) {
     return cached;
-  } else {
-    const metadata = await fetchMetadata();
-    await localForage.setItem<FileMetadata>(key, metadata);
-    return metadata;
   }
+
+  const metadata = await fetchMetadata();
+  if (key) {
+    await localForage.setItem<FileMetadata>(key, metadata);
+  }
+  return metadata;
 };
 
 /**

packages/netlify-cms-lib-util/src/implementation.ts

@@ -162,7 +162,7 @@ type ReadFile = (
   options: { parseText: boolean },
 ) => Promise<string | Blob>;
 
-type ReadFileMetadata = (path: string, id: string) => Promise<FileMetadata>;
+type ReadFileMetadata = (path: string, id: string | null | undefined) => Promise<FileMetadata>;
 
 type ReadUnpublishedFile = (
   key: string,
@@ -183,9 +183,7 @@ const fetchFiles = async (
           try {
             const [data, fileMetadata] = await Promise.all([
               readFile(file.path, file.id, { parseText: true }),
-              file.id
-                ? readFileMetadata(file.path, file.id)
-                : Promise.resolve({ author: '', updatedOn: '' }),
+              readFileMetadata(file.path, file.id),
             ]);
             resolve({ file: { ...file, ...fileMetadata }, data: data as string });
             sem.leave();

packages/netlify-cms-lib-util/src/unsentRequest.js

@@ -49,26 +49,23 @@ const ensureRequestArg = func => req => func(maybeRequestArg(req));
 const ensureRequestArg2 = func => (arg, req) => func(arg, maybeRequestArg(req));
 
 // This actually performs the built request object
-const performRequest = ensureRequestArg(req => fetch(...toFetchArguments(req)));
+const performRequest = ensureRequestArg(req => {
+  const args = toFetchArguments(req);
+  return fetch(...args);
+});
 
 // Each of the following functions takes options and returns another
-// function that performs the requested action on a request. They each
-// default to containing an empty object, so you can simply call them
-// without arguments to generate a request with only those properties.
+// function that performs the requested action on a request.
 const getCurriedRequestProcessor = flow([ensureRequestArg2, curry]);
-const getPropSetFunctions = path => [
-  getCurriedRequestProcessor((val, req) => req.setIn(path, val)),
-  getCurriedRequestProcessor((val, req) => (req.getIn(path) ? req : req.setIn(path, val))),
-];
-const getPropMergeFunctions = path => [
-  getCurriedRequestProcessor((obj, req) => req.updateIn(path, (p = Map()) => p.merge(obj))),
-  getCurriedRequestProcessor((obj, req) => req.updateIn(path, (p = Map()) => Map(obj).merge(p))),
-];
+const getPropSetFunction = path => getCurriedRequestProcessor((val, req) => req.setIn(path, val));
+const getPropMergeFunction = path =>
+  getCurriedRequestProcessor((obj, req) => req.updateIn(path, (p = Map()) => p.merge(obj)));
 
-const [withMethod, withDefaultMethod] = getPropSetFunctions(['method']);
-const [withBody, withDefaultBody] = getPropSetFunctions(['body']);
-const [withParams, withDefaultParams] = getPropMergeFunctions(['params']);
-const [withHeaders, withDefaultHeaders] = getPropMergeFunctions(['headers']);
+const withMethod = getPropSetFunction(['method']);
+const withBody = getPropSetFunction(['body']);
+const withNoCache = getPropSetFunction(['cache'])('no-cache');
+const withParams = getPropMergeFunction(['params']);
+const withHeaders = getPropMergeFunction(['headers']);
 
 // withRoot sets a root URL, unless the URL is already absolute
 const absolutePath = new RegExp('^(?:[a-z]+:)?//', 'i');
@@ -83,24 +80,15 @@ const withRoot = getCurriedRequestProcessor((root, req) =>
   }),
 );
 
-// withTimestamp needs no argument and has to run as late as possible,
-// so it calls `withParams` only when it's actually called with a
-// request.
-const withTimestamp = ensureRequestArg(req => withParams({ ts: new Date().getTime() }, req));
-
 export default {
   toURL,
   fromURL,
   fromFetchArguments,
   performRequest,
   withMethod,
-  withDefaultMethod,
   withBody,
-  withDefaultBody,
   withHeaders,
-  withDefaultHeaders,
   withParams,
-  withDefaultParams,
   withRoot,
-  withTimestamp,
+  withNoCache,
 };