feat: support decoding query parameters into pointers

Also fix incorrect error message and bad reference to "matches".

cmd/happy/main.go

@@ -351,24 +351,31 @@ func genQueryDecoderFunc(gctx *genContext, paramType types.Type) (name string, e
  w = w.Push()
  for i := 0; i < strct.NumFields(); i++ {
  field := strct.Field(i)
- fieldName := lcFirst(strings.ReplaceAll(field.Name(), ".", ""))
+ fieldName := lcFirst(field.Name())
  w.L("if q, ok := p[%q]; ok {", fieldName)
  w = w.Push()
- switch field.Type().String() {
+ fieldType := field.Type()
+ strctRef := "out"
+ if _, ptr := fieldType.(*types.Pointer); ptr {
+ fieldType = fieldType.(*types.Pointer).Elem()
+ w.L("out.%s = new(%s)", field.Name(), fieldType)
+ strctRef = "*" + strctRef
+ }
+ switch fieldType.String() {
  case "bool":
  gctx.Import("strconv")
- w.L("if out.%s, err = strconv.ParseBool(q[len(q)-1]); err != nil {", field.Name())
- w.L(` return fmt.Errorf("failed to decode query parameter \"%s\" as %s: %%w", err)`, fieldName, field.Type())
+ w.L("if %s.%s, err = strconv.ParseBool(q[len(q)-1]); err != nil {", strctRef, field.Name())
+ w.L(` return fmt.Errorf("failed to decode query parameter \"%s\" as %s: %%w", err)`, fieldName, fieldType)
  w.L("}")
  case "int":
  gctx.Import("strconv")
- w.L("if out.%s, err = strconv.Atoi(q[len(q)-1]); err != nil {", field.Name())
- w.L(` return fmt.Errorf("failed to decode query parameter \"%s\" as %s: %%w", err)`, fieldName, field.Type())
+ w.L("if %s.%s, err = strconv.Atoi(q[len(q)-1]); err != nil {", strctRef, field.Name())
+ w.L(` return fmt.Errorf("failed to decode query parameter \"%s\" as %s: %%w", err)`, fieldName, fieldType)
  w.L("}")
  case "string":
- w.L("out.%s = q[len(q)-1]", field.Name())
+ w.L("%s.%s = q[len(q)-1]", strctRef, field.Name())
  default:
- return "", fmt.Errorf("can't decode query parameter into field %s.%s of type %s", paramType, field.Name(), field.Type())
+ return "", fmt.Errorf("can't decode query parameter into field %s.%s of type %s, only int, string and bool are supported", paramType, field.Name(), field.Type())
  }
  w = w.Pop()
  w.L("}")
@@ -465,9 +472,9 @@ func genEndpoint(gctx *genContext, w *codewriter.Writer, ep endpoint) error {
 
  case bt == "string":
  if bt != ref {
- args = append(args, fmt.Sprintf("%s(matches[%d])", ref, index))
+ args = append(args, fmt.Sprintf("%s(params[%d])", ref, index))
  } else {
- args = append(args, fmt.Sprintf("matches[%d]", index))
+ args = append(args, fmt.Sprintf("params[%d]", index))
  }
 
  case bt == "int":
@@ -505,7 +512,7 @@ func genEndpoint(gctx *genContext, w *codewriter.Writer, ep endpoint) error {
  return fmt.Errorf("%s: %w", pos, err)
  }
  w.L("if err := %s(r.URL.Query(), &param%d); err != nil {", decoderFn, i)
- w.L(` http.Error(w, fmt.Sprintf("Failed to decode query parameters: %s", err), http.StatusBadRequest)`)
+ w.L(` http.Error(w, fmt.Sprintf("Failed to decode query parameters: %%s", err), http.StatusBadRequest)`)
  w.L(" return")
  w.L("}")
  } else {

testdata/main.go

@@ -92,7 +92,7 @@ func (s *Service) CreateUser(r *http.Request, user User) error {
 type Paginate struct {
  Page int
  Size int
- Sparse bool
+ Sparse *bool
 }
 
 //happy:api GET /users