Frontend crash due to invalid citations

[cecheta]

Describe the bug

The frontend crashed after receiving a response from the /custom endpoint. I was not able to obtain the response, however the crash occurred at this line, as citation was undefined:

chat-with-your-data-solution-accelerator/code/frontend/src/components/Answer/AnswerParser.tsx

Line 24 in f755b8e

citation.id = citationIndex; // original doc index to de-dupe

The error most likely occurred because the response contained a citation that did not exist, i.e. [doc6], even though there were only 5 source documents.

The following was observed in the API logs:

Source document 6 not provided, skipping doc
Source document 7 not provided, skipping doc
Source document 8 not provided, skipping doc
Source document 9 not provided, skipping doc

Expected behavior

The frontend application should not crash. Errors should be caught and an handled gracefully, or an appropriate error is returned to the user.

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Debugging information

Steps to reproduce

Difficult to reproduce due to non-deterministic result.

Logs

Provided above.

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Tasks

To be filled in by the engineer picking up the issue