Cors fetchDefinitions SyntaxError: Unexpected token '<', "<!DOCTYPE "... is not valid JSON

[PradeepDu]

Hi Folks,

I am working on EDS Universal Editor. After adding custom blocks in github repo noticing the error on AEM cloud author, non of the pages are editable. Getting error in all 3 json files which were updated 

URL of those json are trying to load throwing 404 on author

resource/component-filters.json

resource/component-definition.json

resource/component-models.json

Error : 

Cors fetchDefinitions SyntaxError: Unexpected token '<', "<!DOCTYPE "... is not valid JSON

Error thrown in cors.js file

catch (e) {
return console.log("Cors fetchDefinitions", e),
null
}

I am new to Adobe EDS.

Any help is highly appreciated. 

Thanks,

Pradeep

[SantoshSai · Accepted solution]

Hi @PradeepDu,

Here is what you can do:

1. Verify file paths in GitHub repo

   • In EDS Universal Editor, these JSON files must be located under your repo path:
     resource/component-filters.json resource/component-definitions.json resource/component-models.json

     Double-check spelling — in your post one is component-definition.json (singular), but Adobe docs expect component-definitions.json (plural).
     A typo here will 100% break things.

2. Check Cloud Manager pipeline deployment

   • After pushing changes, did you redeploy the branch through Cloud Manager?
     If not, AEM Author won’t see the updated resources.

3. Confirm JSON validity

   • Sometimes these files fail silently because of trailing commas or bad JSON.
     Run them through a JSON validator to ensure they are valid.

4. Dispatcher/CDN caching

   • If your Dispatcher is serving an error page instead of the JSON, try bypassing it:
     https://author-pXXXX.adobeaemcloud.com/resource/component-definitions.json

     If this works directly but not through your public endpoint, it’s a dispatcher config issue (may need to allow .json under /resource).

5. Check repo structure matches Adobe requirement

   • Adobe Universal Editor expects:
     /resource/component-definitions.json /resource/component-filters.json /resource/component-models.json

     under the root of your UI config repo.
     If they’re placed under /apps/... or /conf/... instead, AEM won’t find them.

6. Enable Developer Tools in Universal Editor

   • Open Universal Editor > Dev Tools > Network tab.

   • See the actual response body for those JSON requests.
     You’ll probably see a 404 HTML error page, which will confirm whether it’s path or dispatcher related.