wip setting defaults for #206

openapi3/schema.go

@@ -1338,6 +1338,19 @@ func (schema *Schema) visitJSONObject(settings *schemaValidationSettings, value
 		return schema.expectedType(settings, TypeObject)
 	}
 
+	if settings.asreq || settings.asrep {
+		for propName, propSchema := range schema.Properties {
+			if value[propName] == nil {
+				if dlft := propSchema.Value.Default; dlft != nil {
+					value[propName] = dlft
+					if f := settings.defaultsSet; f != nil {
+						settings.onceSettingDefaults.Do(f)
+					}
+				}
+			}
+		}
+	}
+
 	var me MultiError
 
 	// "properties"

openapi3/schema_validation_settings.go

@@ -1,12 +1,19 @@
 package openapi3
 
+import (
+	"sync"
+)
+
 // SchemaValidationOption describes options a user has when validating request / response bodies.
 type SchemaValidationOption func(*schemaValidationSettings)
 
 type schemaValidationSettings struct {
 	failfast     bool
 	multiError   bool
 	asreq, asrep bool // exclusive (XOR) fields
+
+	onceSettingDefaults sync.Once
+	defaultsSet         func()
 }
 
 // FailFast returns schema validation errors quicker.
@@ -25,6 +32,11 @@ func VisitAsResponse() SchemaValidationOption {
 	return func(s *schemaValidationSettings) { s.asreq, s.asrep = false, true }
 }
 
+// DefaultsSet executes the given callback (once) IFF schema validation set default values.
+func DefaultsSet(f func()) SchemaValidationOption {
+	return func(s *schemaValidationSettings) { s.defaultsSet = f }
+}
+
 func newSchemaValidationSettings(opts ...SchemaValidationOption) *schemaValidationSettings {
 	settings := &schemaValidationSettings{}
 	for _, opt := range opts {

openapi3filter/req_resp_decoder.go

@@ -814,7 +814,11 @@ const prefixUnsupportedCT = "unsupported content type"
 
 // decodeBody returns a decoded body.
 // The function returns ParseError when a body is invalid.
-func decodeBody(body io.Reader, header http.Header, schema *openapi3.SchemaRef, encFn EncodingFn) (interface{}, error) {
+func decodeBody(body io.Reader, header http.Header, schema *openapi3.SchemaRef, encFn EncodingFn) (
+	string,
+	interface{},
+	error,
+) {
 	contentType := header.Get(headerCT)
 	if contentType == "" {
 		if _, ok := body.(*multipart.Part); ok {
@@ -824,16 +828,16 @@ func decodeBody(body io.Reader, header http.Header, schema *openapi3.SchemaRef,
 	mediaType := parseMediaType(contentType)
 	decoder, ok := bodyDecoders[mediaType]
 	if !ok {
-		return nil, &ParseError{
+		return "", nil, &ParseError{
 			Kind:   KindUnsupportedFormat,
 			Reason: fmt.Sprintf("%s %q", prefixUnsupportedCT, mediaType),
 		}
 	}
 	value, err := decoder(body, header, schema, encFn)
 	if err != nil {
-		return nil, err
+		return "", nil, err
 	}
-	return value, nil
+	return mediaType, value, nil
 }
 
 func init() {
@@ -982,7 +986,7 @@ func multipartBodyDecoder(body io.Reader, header http.Header, schema *openapi3.S
 		}
 
 		var value interface{}
-		if value, err = decodeBody(part, http.Header(part.Header), valueSchema, subEncFn); err != nil {
+		if _, value, err = decodeBody(part, http.Header(part.Header), valueSchema, subEncFn); err != nil {
 			if v, ok := err.(*ParseError); ok {
 				return nil, &ParseError{path: []interface{}{name}, Cause: v}
 			}

openapi3filter/req_resp_decoder_test.go

@@ -1156,7 +1156,7 @@ func TestDecodeBody(t *testing.T) {
 				}
 				return tc.encoding[name]
 			}
-			got, err := decodeBody(tc.body, h, schemaRef, encFn)
+			_, got, err := decodeBody(tc.body, h, schemaRef, encFn)
 
 			if tc.wantErr != nil {
 				require.Error(t, err)
@@ -1226,7 +1226,7 @@ func TestRegisterAndUnregisterBodyDecoder(t *testing.T) {
 	body := strings.NewReader("foo,bar")
 	schema := openapi3.NewArraySchema().WithItems(openapi3.NewStringSchema()).NewRef()
 	encFn := func(string) *openapi3.Encoding { return nil }
-	got, err := decodeBody(body, h, schema, encFn)
+	_, got, err := decodeBody(body, h, schema, encFn)
 
 	require.NoError(t, err)
 	require.Equal(t, []string{"foo", "bar"}, got)
@@ -1236,7 +1236,7 @@ func TestRegisterAndUnregisterBodyDecoder(t *testing.T) {
 	originalDecoder = RegisteredBodyDecoder(contentType)
 	require.Nil(t, originalDecoder)
 
-	_, err = decodeBody(body, h, schema, encFn)
+	_, _, err = decodeBody(body, h, schema, encFn)
 	require.Equal(t, &ParseError{
 		Kind:   KindUnsupportedFormat,
 		Reason: prefixUnsupportedCT + ` "text/csv"`,

openapi3filter/req_resp_encoder.go

@@ -0,0 +1,27 @@
+package openapi3filter
+
+import (
+	"encoding/json"
+	"fmt"
+)
+
+func encodeBody(body interface{}, mediaType string) ([]byte, error) {
+	encoder, ok := bodyEncoders[mediaType]
+	if !ok {
+		return nil, &ParseError{
+			Kind:   KindUnsupportedFormat,
+			Reason: fmt.Sprintf("%s %q", prefixUnsupportedCT, mediaType),
+		}
+	}
+	return encoder(body)
+}
+
+type bodyEncoder func(body interface{}) ([]byte, error)
+
+var bodyEncoders = map[string]bodyEncoder{
+	"application/json": jsonBodyEncoder,
+}
+
+func jsonBodyEncoder(body interface{}) ([]byte, error) {
+	return json.Marshal(body)
+}

openapi3filter/validate_readonly_test.go

@@ -3,6 +3,7 @@ package openapi3filter
 import (
 	"bytes"
 	"encoding/json"
+	"io/ioutil"
 	"net/http"
 	"testing"
 
@@ -26,6 +27,16 @@ func TestValidatingRequestBodyWithReadOnlyProperty(t *testing.T) {
     "/accounts": {
       "post": {
         "description": "Create a new account",
+        "parameters": [
+          {
+            "in": "query",
+            "name": "q",
+            "schema": {
+              "type": "string",
+              "default": "Q"
+            }
+          }
+        ],
         "requestBody": {
           "required": true,
           "content": {
@@ -34,6 +45,10 @@ func TestValidatingRequestBodyWithReadOnlyProperty(t *testing.T) {
                 "type": "object",
                 "required": ["_id"],
                 "properties": {
+                  "_": {
+                    "type": "boolean",
+                    "default": false
+                  },
                   "_id": {
                     "type": "string",
                     "description": "Unique identifier for this object.",
@@ -61,10 +76,6 @@ func TestValidatingRequestBodyWithReadOnlyProperty(t *testing.T) {
 }
 `
 
-	type Request struct {
-		ID string `json:"_id"`
-	}
-
 	sl := openapi3.NewLoader()
 	doc, err := sl.LoadFromData([]byte(spec))
 	require.NoError(t, err)
@@ -73,7 +84,12 @@ func TestValidatingRequestBodyWithReadOnlyProperty(t *testing.T) {
 	router, err := legacyrouter.NewRouter(doc)
 	require.NoError(t, err)
 
-	b, err := json.Marshal(Request{ID: "bt6kdc3d0cvp6u8u3ft0"})
+	b, err := json.Marshal(struct {
+		Blank bool   `json:"_,omitempty"`
+		ID    string `json:"_id"`
+	}{
+		ID: "bt6kdc3d0cvp6u8u3ft0",
+	})
 	require.NoError(t, err)
 
 	httpReq, err := http.NewRequest(http.MethodPost, "/accounts", bytes.NewReader(b))
@@ -89,4 +105,12 @@ func TestValidatingRequestBodyWithReadOnlyProperty(t *testing.T) {
 		Route:      route,
 	})
 	require.NoError(t, err)
+
+	// Unset default values in body were set
+	validatedReqBody, err := ioutil.ReadAll(httpReq.Body)
+	require.NoError(t, err)
+	require.JSONEq(t, `{"_":false,"_id":"bt6kdc3d0cvp6u8u3ft0"}`, string(validatedReqBody))
+	// Unset default values in URL were set
+	// Unset default values in headers were set
+	// Unset default values in cookies were set
 }

openapi3filter/validate_request.go

@@ -52,7 +52,6 @@ func ValidateRequest(ctx context.Context, input *RequestValidationInput) error {
 		if err = ValidateParameter(ctx, input, parameter); err != nil && !options.MultiError {
 			return err
 		}
-
 		if err != nil {
 			me = append(me, err)
 		}
@@ -63,7 +62,6 @@ func ValidateRequest(ctx context.Context, input *RequestValidationInput) error {
 		if err = ValidateParameter(ctx, input, parameter.Value); err != nil && !options.MultiError {
 			return err
 		}
-
 		if err != nil {
 			me = append(me, err)
 		}
@@ -75,7 +73,6 @@ func ValidateRequest(ctx context.Context, input *RequestValidationInput) error {
 		if err = ValidateRequestBody(ctx, input, requestBody.Value); err != nil && !options.MultiError {
 			return err
 		}
-
 		if err != nil {
 			me = append(me, err)
 		}
@@ -92,7 +89,6 @@ func ValidateRequest(ctx context.Context, input *RequestValidationInput) error {
 		if err = ValidateSecurityRequirements(ctx, input, *security); err != nil && !options.MultiError {
 			return err
 		}
-
 		if err != nil {
 			me = append(me, err)
 		}
@@ -137,6 +133,12 @@ func ValidateParameter(ctx context.Context, input *RequestValidationInput, param
 		}
 		schema = parameter.Schema.Value
 	}
+
+	// // Maybe use default value
+	// if value == nil && schema != nil {
+	// 	value = schema.Default
+	// }
+
 	// Validate a parameter's value.
 	if value == nil {
 		if parameter.Required {
@@ -167,16 +169,13 @@ const prefixInvalidCT = "header Content-Type has unexpected value"
 // The function returns RequestError with ErrInvalidRequired cause when a value is required but not defined.
 // The function returns RequestError with a openapi3.SchemaError cause when a value is invalid by JSON schema.
 func ValidateRequestBody(ctx context.Context, input *RequestValidationInput, requestBody *openapi3.RequestBody) error {
-	var (
-		req  = input.Request
-		data []byte
-	)
-
 	options := input.Options
 	if options == nil {
 		options = DefaultOptions
 	}
 
+	var data []byte
+	req := input.Request
 	if req.Body != http.NoBody && req.Body != nil {
 		defer req.Body.Close()
 		var err error
@@ -221,7 +220,7 @@ func ValidateRequestBody(ctx context.Context, input *RequestValidationInput, req
 	}
 
 	encFn := func(name string) *openapi3.Encoding { return contentType.Encoding[name] }
-	value, err := decodeBody(bytes.NewReader(data), req.Header, contentType.Schema, encFn)
+	mediaType, value, err := decodeBody(bytes.NewReader(data), req.Header, contentType.Schema, encFn)
 	if err != nil {
 		return &RequestError{
 			Input:       input,
@@ -231,8 +230,10 @@ func ValidateRequestBody(ctx context.Context, input *RequestValidationInput, req
 		}
 	}
 
-	opts := make([]openapi3.SchemaValidationOption, 0, 2) // 2 potential opts here
+	defaultsSet := false
+	opts := make([]openapi3.SchemaValidationOption, 0, 3) // 3 potential opts here
 	opts = append(opts, openapi3.VisitAsRequest())
+	opts = append(opts, openapi3.DefaultsSet(func() { defaultsSet = true }))
 	if options.MultiError {
 		opts = append(opts, openapi3.MultiErrors())
 	}
@@ -246,6 +247,21 @@ func ValidateRequestBody(ctx context.Context, input *RequestValidationInput, req
 			Err:         err,
 		}
 	}
+
+	if defaultsSet {
+		var err error
+		if data, err = encodeBody(value, mediaType); err != nil {
+			return &RequestError{
+				Input:       input,
+				RequestBody: requestBody,
+				Reason:      "rewriting failed",
+				Err:         err,
+			}
+		}
+		// Put the data back into the input
+		req.Body = ioutil.NopCloser(bytes.NewReader(data))
+	}
+
 	return nil
 }
 

openapi3filter/validate_response.go

@@ -111,7 +111,7 @@ func ValidateResponse(ctx context.Context, input *ResponseValidationInput) error
 	input.SetBodyBytes(data)
 
 	encFn := func(name string) *openapi3.Encoding { return contentType.Encoding[name] }
-	value, err := decodeBody(bytes.NewBuffer(data), input.Header, contentType.Schema, encFn)
+	_, value, err := decodeBody(bytes.NewBuffer(data), input.Header, contentType.Schema, encFn)
 	if err != nil {
 		return &ResponseError{
 			Input:  input,