Document the need for consistent access to form data through ServerWebExchange [SPR-17291]

[spring-projects-issues]

Spencer Gibb opened SPR-17291 and commented

Either @RequestBody or other subscription (such as spring-cloud-gateway)

 

See also spring-projects/spring-boot#14520

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Affects: 5.0.9

Reference URL: spring-cloud/spring-cloud-gateway#541

Issue Links:

• HiddenHttpMethodFilter breaks HandlerFunction with BodyExtractors.toFormData [SPR-16551] #21094 HiddenHttpMethodFilter breaks HandlerFunction with BodyExtractors.toFormData

Referenced from: commits 9630445

0 votes, 5 watchers

[spring-projects-issues]

Spencer Gibb commented

Also related #21094

[spring-projects-issues]

Rossen Stoyanchev commented

I've turned it into an improvement, since it is by design that the filter reads the body. Typically that wouldn't be an issue with annotated controllers nor functional endpoints where form data is read via ServerWebExchange#getFormData which is cached. However, it's clear there are use cases like Spring Cloud Gateway where the raw request body might need to be read.

[spring-projects-issues]

Rossen Stoyanchev commented

After further thought, I've decided to leave this as is, and document the need for consistent access to the parsed form data through the ServerWebExchange. The alternative of caching both the raw and the parsed content is not ideal.

For the much less common case where the raw form data might still be needed, the FormHttpMessageWriter could be used to do encode the parsed form data back into serialized form.