feat: support query:"<name>" tag

cmd/happy/main.go

@@ -16,6 +16,7 @@ import (
 	"unicode/utf8"
 
 	"github.com/alecthomas/kong"
+	"github.com/fatih/structtag"
 	"golang.org/x/tools/go/packages"
 
 	"github.com/thnxdev/happy/codewriter"
@@ -351,7 +352,14 @@ func genQueryDecoderFunc(gctx *genContext, paramType types.Type) (name string, e
 	w = w.Push()
 	for i := 0; i < strct.NumFields(); i++ {
 		field := strct.Field(i)
+		tags, err := structtag.Parse(strct.Tag(i))
+		if err != nil {
+			return "", fmt.Errorf("invalid struct tag on %s.%s: %w", typeRef, field.Name(), err)
+		}
 		fieldName := lcFirst(field.Name())
+		if tag, err := tags.Get("query"); err == nil {
+			fieldName = tag.Name
+		}
 		w.L("if q, ok := p[%q]; ok {", fieldName)
 		w = w.Push()
 		fieldType := field.Type()

go.mod

@@ -4,6 +4,7 @@ go 1.19
 
 require (
 	github.com/alecthomas/kong v0.7.1
+	github.com/fatih/structtag v1.2.0
 	golang.org/x/tools v0.3.0
 )
 

go.sum

@@ -4,6 +4,8 @@ github.com/alecthomas/kong v0.7.1 h1:azoTh0IOfwlAX3qN9sHWTxACE2oV8Bg2gAwBsMwDQY4
 github.com/alecthomas/kong v0.7.1/go.mod h1:n1iCIO2xS46oE8ZfYCNDqdR0b0wZNrXAIAqro/2132U=
 github.com/alecthomas/repr v0.1.0 h1:ENn2e1+J3k09gyj2shc0dHr/yjaWSHRlrJ4DPMevDqE=
 github.com/alecthomas/repr v0.1.0/go.mod h1:2kn6fqh/zIyPLmm3ugklbEi5hg5wS435eygvNfaDQL8=
+github.com/fatih/structtag v1.2.0 h1:/OdNE99OxoI/PqaW/SuSK9uxxT3f/tcSZgon/ssNSx4=
+github.com/fatih/structtag v1.2.0/go.mod h1:mBJUNpUnHmRKrKlQQlmCrh5PuhftFbNv8Ys4/aAZl94=
 github.com/hexops/gotextdiff v1.0.3 h1:gitA9+qJrrTCsiCl7+kh75nPqQt1cx4ZkudSTLoUqJM=
 github.com/hexops/gotextdiff v1.0.3/go.mod h1:pSWU5MAI3yDq+fZBTazCSJysOMbxWL1BSow5/V2vxeg=
 golang.org/x/mod v0.7.0 h1:LapD9S96VoQRhi/GrNTqeBJFrUjs5UHCAtTlgwA5oZA=

testdata/main.go

@@ -90,8 +90,8 @@ func (s *Service) CreateUser(r *http.Request, user User) error {
 }
 
 type Paginate struct {
-	Page   int
-	Size   int
+	Page   int `query:"p"`
+	Size   int `query:"s"`
 	Sparse *bool
 }