echo middleware

go.mod

@@ -7,17 +7,17 @@ require (
 	github.com/gin-gonic/gin v1.3.0
 	github.com/golang/protobuf v1.3.1 // indirect
 	github.com/json-iterator/go v1.1.6 // indirect
-	github.com/mattn/go-isatty v0.0.7 // indirect
+	github.com/labstack/echo v3.3.10+incompatible
+	github.com/labstack/gommon v0.3.0 // indirect
 	github.com/miketonks/swag v0.0.0-20190624155305-d1f7aa61ab61
 	github.com/modern-go/concurrent v0.0.0-20180306012644-bacd9c7ef1dd // indirect
 	github.com/modern-go/reflect2 v1.0.1 // indirect
-	github.com/stretchr/testify v1.3.0
+	github.com/stretchr/testify v1.4.0
 	github.com/ugorji/go v1.1.4 // indirect
 	github.com/xeipuuv/gojsonpointer v0.0.0-20180127040702-4e3ac2762d5f // indirect
 	github.com/xeipuuv/gojsonreference v0.0.0-20180127040603-bd5ef7bd5415 // indirect
 	github.com/xeipuuv/gojsonschema v1.1.0
 	golang.org/x/net v0.0.0-20190607181551-461777fb6f67 // indirect
 	gopkg.in/go-playground/assert.v1 v1.2.1 // indirect
 	gopkg.in/go-playground/validator.v8 v8.18.2 // indirect
-	gopkg.in/yaml.v2 v2.2.2 // indirect
 )

swag-validator.go

@@ -12,6 +12,7 @@ import (
 	"strings"
 
 	"github.com/gin-gonic/gin"
+	"github.com/labstack/echo"
 	"github.com/miketonks/swag/swagger"
 	"github.com/xeipuuv/gojsonschema"
 )
@@ -140,7 +141,7 @@ func loadValueForKey(properties map[string]interface{}, key string, values []str
 	return result
 }
 
-// SwaggerValidator middleware
+// SwaggerValidator Gin middleware
 func SwaggerValidator(api *swagger.API) gin.HandlerFunc {
 
 	apiMap := map[string]gojsonschema.JSONLoader{}
@@ -283,6 +284,150 @@ func SwaggerValidator(api *swagger.API) gin.HandlerFunc {
 	}
 }
 
+// SwaggerValidatorEcho middleware
+func SwaggerValidatorEcho(api *swagger.API) echo.MiddlewareFunc {
+
+	apiMap := map[string]gojsonschema.JSONLoader{}
+	for _, p := range api.Paths {
+		for _, e := range []*swagger.Endpoint{
+			p.Delete,
+			p.Get,
+			p.Post,
+			p.Put,
+			p.Patch,
+			p.Head,
+			p.Options,
+			p.Trace,
+			p.Connect} {
+			if e != nil && e.Handler != nil {
+				schema := buildRequestSchema(e)
+				schema.Definitions = buildSchemaDefinitions(api)
+				schemaLoader := gojsonschema.NewGoLoader(schema)
+
+				key := e.Method + e.Path
+				apiMap[key] = schemaLoader
+			}
+		}
+	}
+
+	// This part runs at runtime, with context for individual request
+	return func(next echo.HandlerFunc) echo.HandlerFunc {
+		return func(c echo.Context) error {
+			schemaLoader, found := apiMap[c.Request().Method+c.Path()]
+			if !found {
+				return next(c)
+			}
+			ref, _ := schemaLoader.LoadJSON()
+			properties, _ := ref.(map[string]interface{})["properties"].(map[string]interface{})
+
+			document := map[string]interface{}{}
+
+			for _, key := range c.ParamNames() {
+				document[key] = loadValueForKey(properties, key, []string{c.Param(key)})
+			}
+			for k, v := range c.Request().URL.Query() {
+				document[k] = loadValueForKey(properties, k, v)
+			}
+
+			// For muiltipart form, handle params and file uploads
+			if c.Request().Header.Get(echo.HeaderContentType) == "multipart/form-data" {
+				r := c.Request()
+				r.ParseMultipartForm(MaxMemory)
+
+				for k, v := range c.Request().PostForm {
+					document[k] = coerce(v[0], "", "")
+				}
+				if r.MultipartForm != nil && r.MultipartForm.File != nil {
+					for k := range r.MultipartForm.File {
+						document[k] = "x"
+					}
+				}
+			} else if c.Request().Header.Get(echo.HeaderContentType) == "application/x-www-form-urlencoded" {
+				r := c.Request()
+				r.ParseForm()
+
+				body := map[string]interface{}{}
+				for k, v := range c.Request().PostForm {
+					body[k] = coerce(v[0], "", "")
+				}
+				document["body"] = body
+			} else if c.Request().ContentLength > 0 {
+				// For all other types parse body as json, if possible
+
+				// read the response body to a variable
+				var body interface{}
+				b, err := ioutil.ReadAll(c.Request().Body)
+				if err != nil {
+					return c.JSON(
+						http.StatusBadRequest,
+						echo.Map{
+							"message": "Validation error",
+							"details": map[string]string{
+								"body": "Failed to read request body",
+							},
+						},
+					)
+				}
+				err = json.Unmarshal(b, &body)
+				// TODO Consider different error cases: Empty Body, Invalid JSON, Form Data
+				if err != nil {
+					return c.JSON(
+						http.StatusBadRequest,
+						echo.Map{
+							"message": "Validation error",
+							"details": map[string]string{
+								"body": "Invalid JSON format",
+							},
+						},
+					)
+				}
+				document["body"] = body
+
+				//reset the response body to the original unread state
+				c.Request().Body = ioutil.NopCloser(bytes.NewBuffer(b))
+			}
+
+			gojsonschema.Locale = CustomLocale{}
+
+			documentLoader := gojsonschema.NewGoLoader(document)
+			result, err := gojsonschema.Validate(schemaLoader, documentLoader)
+
+			if err != nil {
+				// fmt.Printf("ERROR: %s\n", err)
+				return c.JSON(http.StatusInternalServerError, echo.Map{
+					"message": "swagger document " + err.Error(),
+				})
+
+			} else if result.Valid() {
+				// fmt.Printf("The document is valid\n")
+				next(c)
+			} else {
+				// fmt.Printf("The document is not valid. see errors :\n")
+				errors := map[string]string{}
+				for _, err := range result.Errors() {
+					description := err.Description()
+					details := err.Details()
+
+					field := details["field"].(string)
+					if val, ok := details["property"]; ok {
+						field += "." + val.(string)
+					}
+					field = strings.TrimPrefix(field, "body.")
+					field = strings.TrimPrefix(field, "(root).")
+					errors[field] = description
+				}
+				// fmt.Printf("The document is not valid. see errors : %+v\n", errors)
+				return c.JSON(http.StatusBadRequest, echo.Map{
+					"message": "Validation error",
+					"details": errors,
+				})
+			}
+
+			return nil
+		}
+	}
+}
+
 // Data types are defined here: https://swagger.io/specification/#dataTypes
 func coerce(value string, valueType string, valueFormat string) interface{} {
 	switch valueType {