Wednesday, July 22, 2020

Office Add-In Caching is Problematic

Caching for Javascript based web add-ins for Microsoft Office is super problematic. Hard to make it let go of certain files and use new versions of them. Microsoft gives some instructions on how to clear the add-in cache here but it still won't work sometimes.

Especially problematic files are "FunctionFile.html" and "FunctionFile.js" if the Visual Studio naming convention is to be followed (i.e. how Visual Studio names these files in an auto-generated web add-in project). These files are not downloaded in the task pane's browser instance and therefore caching of them does not follow the same rules; they are extremely sticky and development can get pretty frustrating.

Only way I have found to deal with the problem is rename them in a versioning way whenever I effect changes on the files and want to see the results immediately. Specifically, given that the "Home.html" and "

  1. In the add-in manifest rename "FunctionFile.html" and "Home.html" to "FunctionFile2.html" and "Home2.html", increasing that version number every time you need to refresh the cache.
  2. In "FunctionFile2.html" rename all instances of "FunctionFile.js" to "FunctionFile2.js"
  3. In "Home2.html" rename all instances of "Home.js" to "Home2.js"
  4. Rebuild & republish the solution if you're using the VS based automated process, or upload the changed files to the add-in backend if you're doing it manually.
  5. Go and manually (e.g. over ssh or sftp) rename the .js files to their new versioned names.
  6. Sideload the published xml manifest of the add-in to your Office app and take pleasure in the fact that your changes finally reflect.
Microsoft has produced irritatingly problematic technologies before but I'm having difficulty remembering something as persistently problematic and as irritating as this. They keep throwing their dirty laundry at the developer.

No comments:

Post a Comment