yesodweb / yesodweb/persistent

[Question] derivePersistFieldJSON and dealing with parse failure

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Dominant language
Haskell
Stars
486
Forks
306
PR merge metrics
No merged PRs in 30d

Description

I've hit a runtime error when using derivePersistFieldJSON where some bad JSON had made it's way in to the database by accident. The query which pulls the data out of the database is constructed with esqueleto - it's hard to tell if this be posted here or there!

Is there a way to deal with this?

Originally asked on Twitter but @parsonsmatt directed me to here.

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Research direction

Start by reproducing the runtime failure involving derivePersistFieldJSON and malformed JSON returned by the esqueleto query. Inspect how parse failures are handled at this boundary and determine the expected behavior for invalid database data; the issue does not name files, tests, or a precise completion criterion.

Written by the indexing model from the issue text.

Assessment

Tech stack
haskell
Domain
databases
Issue type
Bug
Difficulty
4/5
Estimated time
3-5 days
Activity status
Stale
Clarity
Needs clarification
Newbie friendliness
25/100

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