🔥 Add function to override form decoder setting

[rockcreation7]

Please provide enough information so that others can review your pull request:

• SetParserDecoder function map all option to form decoder, which allow you to change decoder option globally, use with type ParserConfig, ParserType.

• Added Test_Ctx_BodyParser_WithSetParserDecoder for testing

Explain the details for making this change. What existing problem does the pull request solve?

• You can do custom type in JSON format, Create custom type and related "UnmarshalJSON" method, But in form you need to register converter in decoder, I added option for supporting this feature. In order to solve problem when you need custom type for form.

• Allow set the decoder's zeroEmpty to true, allow not skipping empty input as it will overwrite existing value. 🐛 BodyParser does not save empty string to field #1084

type CustomTime time.Time

var timeConverter = func(value string) reflect.Value {
	if v, err := time.Parse("2006-01-02", value); err == nil {
		return reflect.ValueOf(v)
	}
	return reflect.Value{}
}

customType := ParserType{
		Customtype: CustomType{},
		Converter:  timeConverter,
}

SetParserDecoder(
         BodyParserConfig{
		IgnoreUnknownKeys: true,
		BodyParserType:    []ParserType{customType},
		ZeroEmpty:         true,
		SetAliasTag:       "form",
	}
)

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[rockcreation7]

Any suggestion for moving forward on this PR will be appreciated, or any idea should be further investigate, wish to provide help, Thanks.

[stale]

👋 Hello. Is this still relevant? If so, what is blocking it? Is there anything you can do to help move it forward?

This issue has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs.
Thank you for your contributions.

[Israel-Laguan]

LGTM

[ReneWerner87]

can we use the method for the initial write of the decoder pool ?
https://github.com/gofiber/fiber/blob/master/ctx.go#L274
@rockcreation7

[rockcreation7]

Sure, I can help update the doc on this, thanks.

Please feel free to let me know anything that can help.

[rockcreation7]

or you mean I put a change to the initial write?

[ReneWerner87]

or you mean I put a change to the initial write?

@rockcreation7
yes exactly, with the initial set you can also use your method or ?

will merge it directly after the adjustment

[ReneWerner87]

@rockcreation7 can you rename it a bit, because the decoder is used by the query parser and body parser

maybe something just called parser config or type

[rockcreation7]

Thanks, will update.

[rockcreation7]

#1555

Renamed function:
SetBodyParserDecoder to SetParserDecoder

Type:
BodyParserType > ParserType
bodyParserConfig > parserConfig
BodyParserConfig > ParserConfig