Issue
The business Rules panel is blank, but other aspects of the UI work correctly (i.e. Merchandiser, Rewrite, etc).
Also, a network analysis of the page load shows a call to the "targeted-docs" endpoint that fails with a status code of 431, due to the GET request being thousands of characters long:
The actual cause is due to UI attempting to retrieve information for all document IDs that are referenced by the rules on that page of rules. For example, a Boost List rule that references 20 documents will cause 20 docId's to be added to the targeted-docs call. All the document id's for all the rules on the page are concatenated together for the call.
Environment
Fusion 5
Resolution
Long Term: A bug fix is underway to fix the issue long term
Medium Term: Curate rules differently
Delete/remove any unneeded rules, especially if they mention lots of document id's.
Split up very long lists of document id's into multiple rules. Fewer id's per rule will help keep the length of the targeted-docs call smaller
Short Term: Add dummy rules via the Query Rewrite API
By adding new dummy rules via the query rewrite API that don't fire, and don't contain any document id's, the UI will use a shorter targeted-docs call. In essence, we're pushing the rules with the longer lists of id's to a later page of the UI, where the issue doesn't occur.
To add a dummy rule, make a POST to the query rewrite API endpoint:
https://<DOMAIN:PORT>/api/apps/<APP_NAME>/query-rewrite/instances
With a payload like:
{ "name": "dummy00",
"type": "banner",
"banner_url": "www.somewhere.com",
"matching":"keywords",
"search_terms":["TTHISSRRULESSHOULDNNEEVERFFIRE"]
}You will likely need to add 10-15 of these dummy rules (each with a slightly different "name") to ensure enough rules with long lists of id's get pushed to page 2 of the UI.