Use the built-in JSON library #6481
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| Now [`/hello/Frank`] in your browser should display `From messenger Frank` as plain text without any HTML. | ||
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| A step beyond this is rendering pure JSON with the [`json/2`] function. We need to pass it something that the [Jason library](`Jason`) can decode into JSON, such as a map. (Jason is one of Phoenix's dependencies.) | ||
| A step beyond this is rendering pure JSON with the [`json/2`] function. We need to pass it something that the [JSON library](https://hexdocs.pm/elixir/JSON.html) can decode into JSON, such as a map. |
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Here's how it looks like with mouse hover:
| format: "\n$time $metadata[$level] $message\n" | ||
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| config :phoenix, | ||
| json_library: Jason, |
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Probably here we would need to have something similar to if Code.ensure_loaded?(JSON), do: JSON, else: Jason if that conditional loading trick makes sense.
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I think it does and yes, we definitely need it (and also adjust the tests to assert the correct errors in CI)
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Oh yeah, for sure. I wasn't certain if the said approach (determining JSON availability by Code.ensure_loaded?) is the correct one. But if it will do, then yes, I'll update the tests
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We can wait for José to chime in. Sometimes you need Code.ensure_compiled, but I think for a built in module ensure_loaded should be fine?
lib/phoenix.ex
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| """ | ||
| def json_library do | ||
| Application.get_env(:phoenix, :json_library, Jason) | ||
| Application.get_env(:phoenix, :json_library, @default_json_library) |
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We cannot change the default here, as that would be a breaking change. We can only change it in new apps.
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Yes, I agree. It makes things a bit simpler for this PR:
- Mark the default library in
Phoenix.json_libraryas a breaking change for Phoenix v2.0 - Use
JSONfor new apps - Make sure that tests pass with both
JSONandJasonlibraries
What I'm not sure is whether changes in config/config.exs are safe?
I could be wrong, but it seems that they aren't propagated to library users. The users will only see variables from application.env, right?
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| assert_raise json_error, | ||
| ~r/invalid byte 111 at position \(byte offset\) 0|unexpected byte at position 0: 0x6F \("o"\)/, fn -> |
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Not the most elegant solution, but...
Address #6461
The changes set the built-in JSON library as a default JSON library.
The idea is to check whether the built-in JSON library is present and use it if so:
Correct me if I'm wrong, but I think a naive check of whether the library is present during compilation time should work, as it's a built-in library.
What I'm not sure about is whether such a move results in a breaking change.
It could be a breaking change for projects that don't specify the
json_libraryand use@derive Jason.Encoderon structures passed toPhoenix.Controller.json/2. That sounds pretty niche, especially given that the template project includes:Also, I'm specifically leaving the
jasondependency in place for pre-27 OTP versions.Please let me know what you think and whether the changes make sense. In other words, maybe it would be better to stick with
Jasonuntil Phoenix requires OTP 28.Similar discussions / changes:
Use Jason instead of Poison for json encoding by chrismccord #2734phoenixframework/phoenix
Investigate using Jason instead of Poison #2693phoenixframework/phoenix
Use JSON instead of Jason by kubosuke #234felt/geo