fix bind with map[string]interface{} for json post but with no params

[wonderflow]

hello, I hope to handle a post request with no params, but the binddata failed me.

bind data will check type as struct, I hope to decode use map[string]interface{}

hope to be merged.

[codecov]

Codecov Report

Merging #989 into master will not change coverage.
The diff coverage is 100%.

@@           Coverage Diff           @@
##           master     #989   +/-   ##
=======================================
  Coverage   76.56%   76.56%           
=======================================
  Files          27       27           
  Lines        2232     2232           
=======================================
  Hits         1709     1709           
  Misses        400      400           
  Partials      123      123

Impacted Files	Coverage Δ
bind.go	80.39% <100%> (ø)	⬆️

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[vishr]

@goenning can you review this change?

[goenning]

@vishr LGTM, > 0 is the right condition.

[vishr]

@goenning A request similar request with params will fail. This change has introduced new bugs recently, do you think this can be handled in a custom binder?

[goenning]

@vishr Are you referring to #988? If so, this PR will fix that. Did you notice any other regression?

I'd love to keep this on DefaultBinder as binding from route parameter is not an application-specific feature.

[vishr]

@goenning I understand this PR will fix it, however, I could see a request with params binding to a map will fail. e.g.

Path: /users/:id
Payload:

{
  "name": "John Snow"
}

[goenning]

@vishr I see there's a new check reflect.TypeOf(ptr).Elem().Kind() == reflect.Slice on bindPathData. Changing it to typ.Kind() != reflect.Struct would fix it.

I get your point, there could be more unforeseen binding issues. But still, I'd vote for keeping it. I've upgrade to the latest commit and had no issues because all my scenarios are binding to a struct, not slices/maps. But such cases are now covered by unit tests.

[vishr]

@goenning Multiple bugs started popping just after this change and if I am not wrong this change was done for #980.

[wonderflow]

@vishr @goenning so what will be done to this issue?

[vishr]

@wonderflow I have reverted this change, things should work fine now.

[wonderflow]

yes, I have tested, it's ok now, thanks