Meme transcription: Panel 1. Two images of JSON, one is the empty object, one is an object in which the key name maps to the value null. Caption: “Corporate needs you to find the difference between this picture and this picture”

Panel 2. The Java backend dev answers, “They’re the same picture.”

  • paholg@lemm.ee
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    5 months ago

    They’re semantically different for PATCH requests. The first does nothing, the second should unset the name field.

    • expr
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      5 months ago

      Only if using JSON merge patch, and that’s the only time it’s acceptable. But JSON patch should be preferred over JSON merge patch anyway.

      Servers should accept both null and undefined for normal request bodies, and clients should treat both as the same in responses. API designers should not give each bespoke semantics.

      • arendjr
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        5 months ago

        JSON patch is a dangerous thing to use over a network. It will allow you to change things inside array indices without knowing whether the same thing is still at that index by the time the server processes your request. That’s a recipe for race conditions.

        • expr
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          5 months ago

          That’s what the If-Match header is for. It prevents this problem.

          That being said, I generally think PUTs are preferable to PATCHes for simplicity.

      • masterspace@lemmy.ca
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        5 months ago

        Why?

        Because Java struggles with basic things?

        It’s absurd to send that much data on every patch request, to express no more information, but just to appease the shittiness of Java.