Support openapiV3 oneOf for fields/responses (#1671)

* fix: drive new schema from ref and field tags

* feat: support openapi-v3 oneOf tag

* feat: support openapi-v3 oneOf for response

field_parserv3.go

@@ -83,13 +83,15 @@ func (sf *structFieldV3) setMax(valValue string) {
 
 type tagBaseFieldParserV3 struct {
 	p     *Parser
+	file  *ast.File
 	field *ast.Field
 	tag   reflect.StructTag
 }
 
-func newTagBaseFieldParserV3(p *Parser, field *ast.Field) FieldParserV3 {
+func newTagBaseFieldParserV3(p *Parser, file *ast.File, field *ast.Field) FieldParserV3 {
 	fieldParser := tagBaseFieldParserV3{
 		p:     p,
+		file:  file,
 		field: field,
 		tag:   "",
 	}
@@ -134,9 +136,10 @@ func (ps *tagBaseFieldParserV3) ComplementSchema(schema *spec.RefOrSpec[spec.Sch
 		if err != nil {
 			return err
 		}
-		// if !reflect.ValueOf(newSchema).IsZero() {
-		// 	*schema = *(newSchema.WithAllOf(*schema.Spec))
-		// }
+		if !reflect.ValueOf(newSchema).IsZero() {
+			newSchema.AllOf = []*spec.RefOrSpec[spec.Schema]{{Spec: schema.Spec}}
+			*schema = spec.RefOrSpec[spec.Schema]{Spec: &newSchema}
+		}
 		return nil
 	}
 
@@ -339,6 +342,19 @@ func (ps *tagBaseFieldParserV3) complementSchema(schema *spec.Schema, types []st
 		}
 	}
 
+	var oneOfSchemas []*spec.RefOrSpec[spec.Schema]
+	oneOfTagValue := ps.tag.Get(oneOfTag)
+	if oneOfTagValue != "" {
+		oneOfTypes := strings.Split((oneOfTagValue), ",")
+		for _, oneOfType := range oneOfTypes {
+			oneOfSchema, err := ps.p.getTypeSchemaV3(oneOfType, ps.file, true)
+			if err != nil {
+				return fmt.Errorf("can't find oneOf type %q: %v", oneOfType, err)
+			}
+			oneOfSchemas = append(oneOfSchemas, oneOfSchema)
+		}
+	}
+
 	elemSchema := schema
 
 	if field.schemaType == ARRAY {
@@ -362,6 +378,7 @@ func (ps *tagBaseFieldParserV3) complementSchema(schema *spec.Schema, types []st
 	elemSchema.MinLength = field.minLength
 	elemSchema.Enum = field.enums
 	elemSchema.Pattern = field.pattern
+	elemSchema.OneOf = oneOfSchemas
 
 	return nil
 }

go.mod

@@ -9,7 +9,7 @@ require (
 	github.com/pkg/errors v0.9.1
 	github.com/stretchr/testify v1.8.2
 	github.com/sv-tools/openapi v0.2.1
-	golang.org/x/tools v0.8.0
+	golang.org/x/tools v0.13.0
 	sigs.k8s.io/yaml v1.3.0
 )
 
@@ -30,7 +30,7 @@ require (
 	github.com/mailru/easyjson v0.7.7 // indirect
 	github.com/pmezard/go-difflib v1.0.0 // indirect
 	github.com/urfave/cli/v2 v2.25.1
-	golang.org/x/sys v0.7.0 // indirect
+	golang.org/x/sys v0.12.0 // indirect
 	gopkg.in/yaml.v2 v2.4.0
 	gopkg.in/yaml.v3 v3.0.1 // indirect
 )

go.sum

@@ -64,11 +64,11 @@ github.com/urfave/cli/v2 v2.25.1 h1:zw8dSP7ghX0Gmm8vugrs6q9Ku0wzweqPyshy+syu9Gw=
 github.com/urfave/cli/v2 v2.25.1/go.mod h1:GHupkWPMM0M/sj1a2b4wUrWBPzazNrIjouW6fmdJLxc=
 github.com/xrash/smetrics v0.0.0-20201216005158-039620a65673 h1:bAn7/zixMGCfxrRTfdpNzjtPYqr8smhKouy9mxVdGPU=
 github.com/xrash/smetrics v0.0.0-20201216005158-039620a65673/go.mod h1:N3UwUGtsrSj3ccvlPHLoLsHnpR27oXr4ZE984MbSER8=
-golang.org/x/mod v0.10.0 h1:lFO9qtOdlre5W1jxS3r/4szv2/6iXxScdzjoBMXNhYk=
-golang.org/x/sys v0.7.0 h1:3jlCCIQZPdOYu1h8BkNvLz8Kgwtae2cagcG/VamtZRU=
-golang.org/x/sys v0.7.0/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
-golang.org/x/tools v0.8.0 h1:vSDcovVPld282ceKgDimkRSC8kpaH1dgyc9UMzlt84Y=
-golang.org/x/tools v0.8.0/go.mod h1:JxBZ99ISMI5ViVkT1tr6tdNmXeTrcpVSD3vZ1RsRdN4=
+golang.org/x/mod v0.12.0 h1:rmsUpXtvNzj340zd98LZ4KntptpfRHwpFOHG188oHXc=
+golang.org/x/sys v0.12.0 h1:CM0HF96J0hcLAwsHPJZjfdNzs0gftsLfgKt57wWHJ0o=
+golang.org/x/sys v0.12.0/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
+golang.org/x/tools v0.13.0 h1:Iey4qkscZuv0VvIt8E0neZjtPVQFSc870HQ448QgEmQ=
+golang.org/x/tools v0.13.0/go.mod h1:HvlwmtVNQAhOuCjW7xxvovg8wbNq7LwfXh/k7wXUl58=
 gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=
 gopkg.in/check.v1 v1.0.0-20180628173108-788fd7840127/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=
 gopkg.in/check.v1 v1.0.0-20200227125254-8fa46927fb4f/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=

operation.go

@@ -423,6 +423,7 @@ const (
 	extensionsTag       = "extensions"
 	collectionFormatTag = "collectionFormat"
 	patternTag          = "pattern"
+	oneOfTag            = "oneOf"
 )
 
 var regexAttributes = map[string]*regexp.Regexp{

operationv3.go

@@ -5,6 +5,7 @@ import (
 	"fmt"
 	"go/ast"
 	"log"
+	"maps"
 	"net/http"
 	"strconv"
 	"strings"
@@ -926,22 +927,15 @@ func (o *OperationV3) ParseResponseComment(commentLine string, astFile *ast.File
 
 	for _, codeStr := range strings.Split(matches[1], ",") {
 		if strings.EqualFold(codeStr, defaultTag) {
-			response := o.DefaultResponse()
-			response.Description = description
-
-			mimeType := "application/json" // TODO: set correct mimeType
-			setResponseSchema(response, mimeType, schema)
-
-			continue
-		}
-
-		code, err := strconv.Atoi(codeStr)
-		if err != nil {
-			return fmt.Errorf("can not parse response comment \"%s\"", commentLine)
-		}
-
-		if description == "" {
-			description = http.StatusText(code)
+			codeStr = ""
+		} else {
+			code, err := strconv.Atoi(codeStr)
+			if err != nil {
+				return fmt.Errorf("can not parse response comment \"%s\"", commentLine)
+			}
+			if description == "" {
+				description = http.StatusText(code)
+			}
 		}
 
 		response := spec.NewResponseSpec()
@@ -979,15 +973,12 @@ func (o *OperationV3) ParseEmptyResponseComment(commentLine string) error {
 
 	for _, codeStr := range strings.Split(matches[1], ",") {
 		if strings.EqualFold(codeStr, defaultTag) {
-			response := o.DefaultResponse()
-			response.Description = description
-
-			continue
-		}
-
-		_, err := strconv.Atoi(codeStr)
-		if err != nil {
-			return fmt.Errorf("can not parse response comment \"%s\"", commentLine)
+			codeStr = ""
+		} else {
+			_, err := strconv.Atoi(codeStr)
+			if err != nil {
+				return fmt.Errorf("can not parse response comment \"%s\"", commentLine)
+			}
 		}
 
 		o.AddResponse(codeStr, newResponseWithDescription(description))
@@ -996,21 +987,10 @@ func (o *OperationV3) ParseEmptyResponseComment(commentLine string) error {
 	return nil
 }
 
-// DefaultResponse return the default response member pointer.
-func (o *OperationV3) DefaultResponse() *spec.Response {
-	if o.Responses.Spec.Default == nil {
-		o.Responses.Spec.Default = spec.NewResponseSpec()
-		o.Responses.Spec.Default.Spec.Spec.Headers = make(map[string]*spec.RefOrSpec[spec.Extendable[spec.Header]])
-	}
-
-	if o.Responses.Spec.Default.Spec.Spec.Content == nil {
-		o.Responses.Spec.Default.Spec.Spec.Content = make(map[string]*spec.Extendable[spec.MediaType])
-	}
-
-	return o.Responses.Spec.Default.Spec.Spec
-}
-
 // AddResponse add a response for a code.
+// If the code is already exist, it will merge with the old one:
+// 1. The description will be replaced by the new one if the new one is not empty.
+// 2. The content schema will be merged using `oneOf` if the new one is not empty.
 func (o *OperationV3) AddResponse(code string, response *spec.RefOrSpec[spec.Extendable[spec.Response]]) {
 	if response.Spec.Spec.Headers == nil {
 		response.Spec.Spec.Headers = make(map[string]*spec.RefOrSpec[spec.Extendable[spec.Header]])
@@ -1020,24 +1000,74 @@ func (o *OperationV3) AddResponse(code string, response *spec.RefOrSpec[spec.Ext
 		o.Responses.Spec.Response = make(map[string]*spec.RefOrSpec[spec.Extendable[spec.Response]])
 	}
 
-	o.Responses.Spec.Response[code] = response
+	res := response
+	var prev *spec.RefOrSpec[spec.Extendable[spec.Response]]
+	if code != "" {
+		prev = o.Responses.Spec.Response[code]
+	} else {
+		prev = o.Responses.Spec.Default
+	}
+	if prev != nil { // merge into prev
+		res = prev
+		if response.Spec.Spec.Description != "" {
+			prev.Spec.Spec.Description = response.Spec.Spec.Description
+		}
+		if len(response.Spec.Spec.Content) > 0 {
+			// responses should only have one content type
+			singleKey := ""
+			for k := range response.Spec.Spec.Content {
+				singleKey = k
+				break
+			}
+			if prevMediaType := prev.Spec.Spec.Content[singleKey]; prevMediaType == nil {
+				prev.Spec.Spec.Content = response.Spec.Spec.Content
+			} else {
+				newMediaType := response.Spec.Spec.Content[singleKey]
+				if len(newMediaType.Extensions) > 0 {
+					if prevMediaType.Extensions == nil {
+						prevMediaType.Extensions = make(map[string]interface{})
+					}
+					maps.Copy(prevMediaType.Extensions, newMediaType.Extensions)
+				}
+				if len(newMediaType.Spec.Examples) > 0 {
+					if prevMediaType.Spec.Examples == nil {
+						prevMediaType.Spec.Examples = make(map[string]*spec.RefOrSpec[spec.Extendable[spec.Example]])
+					}
+					maps.Copy(prevMediaType.Spec.Examples, newMediaType.Spec.Examples)
+				}
+				if prevSchema := prevMediaType.Spec.Schema; prevSchema.Ref != nil || prevSchema.Spec.OneOf == nil {
+					oneOfSchema := spec.NewSchemaSpec()
+					oneOfSchema.Spec.OneOf = []*spec.RefOrSpec[spec.Schema]{prevSchema, newMediaType.Spec.Schema}
+					prevMediaType.Spec.Schema = oneOfSchema
+				} else {
+					prevSchema.Spec.OneOf = append(prevSchema.Spec.OneOf, newMediaType.Spec.Schema)
+				}
+			}
+		}
+	}
+
+	if code != "" {
+		o.Responses.Spec.Response[code] = res
+	} else {
+		o.Responses.Spec.Default = res
+	}
 }
 
 // ParseEmptyResponseOnly parse only comment out status code ,eg: @Success 200.
 func (o *OperationV3) ParseEmptyResponseOnly(commentLine string) error {
 	for _, codeStr := range strings.Split(commentLine, ",") {
+		var description string
 		if strings.EqualFold(codeStr, defaultTag) {
-			_ = o.DefaultResponse()
-
-			continue
-		}
-
-		code, err := strconv.Atoi(codeStr)
-		if err != nil {
-			return fmt.Errorf("can not parse response comment \"%s\"", commentLine)
+			codeStr = ""
+		} else {
+			code, err := strconv.Atoi(codeStr)
+			if err != nil {
+				return fmt.Errorf("can not parse response comment \"%s\"", commentLine)
+			}
+			description = http.StatusText(code)
 		}
 
-		o.AddResponse(codeStr, newResponseWithDescription(http.StatusText(code)))
+		o.AddResponse(codeStr, newResponseWithDescription(description))
 	}
 
 	return nil

parserv3.go

@@ -15,8 +15,8 @@ import (
 	"github.com/sv-tools/openapi/spec"
 )
 
-// FieldParserFactoryV3 func(ps *Parser, field *ast.Field) FieldParserV3 create FieldParser.
-type FieldParserFactoryV3 func(ps *Parser, field *ast.Field) FieldParserV3
+// FieldParserFactoryV3 create FieldParser.
+type FieldParserFactoryV3 func(ps *Parser, file *ast.File, field *ast.Field) FieldParserV3
 
 // FieldParserV3 parse struct field.
 type FieldParserV3 interface {
@@ -903,7 +903,7 @@ func (p *Parser) parseStructFieldV3(file *ast.File, field *ast.Field) (map[strin
 		}
 	}
 
-	ps := p.fieldParserFactoryV3(p, field)
+	ps := p.fieldParserFactoryV3(p, file, field)
 
 	if ps.ShouldSkip() {
 		return nil, nil, nil