Rework router (#210)

Author: fenollp

README.md

@@ -37,10 +37,9 @@ Here's some projects that depend on _kin-openapi_:
     * Support for OpenAPI 3 files, including serialization, deserialization, and validation.
   * _openapi3filter_ ([godoc](https://godoc.org/github.com/getkin/kin-openapi/openapi3filter))
     * Validates HTTP requests and responses
+    * Provides a [gorilla/mux](https://github.com/gorilla/mux) router for OpenAPI operations
   * _openapi3gen_ ([godoc](https://godoc.org/github.com/getkin/kin-openapi/openapi3gen))
     * Generates `*openapi3.Schema` values for Go types.
-  * _pathpattern_ ([godoc](https://godoc.org/github.com/getkin/kin-openapi/pathpattern))
-    * Matches strings with OpenAPI path patterns ("/path/{parameter}")
 
 # Some recipes
 ## Loading OpenAPI document
@@ -51,19 +50,12 @@ swagger, err := openapi3.NewSwaggerLoader().LoadSwaggerFromFile("swagger.json")
 
 ## Getting OpenAPI operation that matches request
 ```go
-func GetOperation(httpRequest *http.Request) (*openapi3.Operation, error) {
-  // Load Swagger file
-  router := openapi3filter.NewRouter().WithSwaggerFromFile("swagger.json")
-
-  // Find route
-  route, _, err := router.FindRoute("GET", req.URL)
-  if err != nil {
-    return nil, err
-  }
-
-  // Get OpenAPI 3 operation
-  return route.Operation
-}
+loader := openapi3.NewSwaggerLoader()
+spec, _ := loader.LoadSwaggerFromData([]byte(`...`))
+_ := spec.Validate(loader.Context)
+router, _ := openapi3filter.NewRouter(spec)
+route, pathParams, _ := router.FindRoute(httpRequest)
+// Do something with route.Operation
 ```
 
 ## Validating HTTP requests/responses
@@ -81,12 +73,15 @@ import (
 )
 
 func main() {
-	router := openapi3filter.NewRouter().WithSwaggerFromFile("swagger.json")
 	ctx := context.Background()
+	loader := &openapi3.SwaggerLoader{Context: ctx}
+	spec, _ := loader.LoadSwaggerFromFile("openapi3_spec.json")
+	_ := spec.Validate(ctx)
+	router, _ := openapi3filter.NewRouter(spec)
 	httpReq, _ := http.NewRequest(http.MethodGet, "/items", nil)
 
 	// Find route
-	route, pathParams, _ := router.FindRoute(httpReq.Method, httpReq.URL)
+	route, pathParams, _ := router.FindRoute(httpReq)
 
 	// Validate request
 	requestValidationInput := &openapi3filter.RequestValidationInput{

go.mod

@@ -5,6 +5,7 @@ go 1.16
 require (
 	github.com/ghodss/yaml v1.0.0
 	github.com/go-openapi/jsonpointer v0.19.5
+	github.com/gorilla/mux v1.8.0
 	github.com/stretchr/testify v1.5.1
 	gopkg.in/yaml.v2 v2.3.0 // indirect
 )

go.sum

@@ -7,6 +7,8 @@ github.com/go-openapi/jsonpointer v0.19.5 h1:gZr+CIYByUqjcgeLXnQu2gHYQC9o73G2XUe
 github.com/go-openapi/jsonpointer v0.19.5/go.mod h1:Pl9vOtqEWErmShwVjC8pYs9cog34VGT37dQOVbmoatg=
 github.com/go-openapi/swag v0.19.5 h1:lTz6Ys4CmqqCQmZPBlbQENR1/GucA2bzYTE12Pw4tFY=
 github.com/go-openapi/swag v0.19.5/go.mod h1:POnQmlKehdgb5mhVOsnJFsivZCEZ/vjK9gh66Z9tfKk=
+github.com/gorilla/mux v1.8.0 h1:i40aqfkR1h2SlN9hojwV5ZA91wcXFOvkdNIeFDP5koI=
+github.com/gorilla/mux v1.8.0/go.mod h1:DVbg23sWSpFRCP0SfiEN6jmj59UnW/n46BH5rLB71So=
 github.com/kr/pretty v0.1.0 h1:L/CwN0zerZDmRFUapSPitk6f+Q3+0za1rQkzVuMiMFI=
 github.com/kr/pretty v0.1.0/go.mod h1:dAy3ld7l9f0ibDNOQOHHMYYIIbhfbHSm3C4ZsoJORNo=
 github.com/kr/pty v1.1.1/go.mod h1:pFQYn66WHrOpPYNljwOMqo10TkYh1fy3cYio2l3bCsQ=

openapi3/server.go

@@ -3,6 +3,7 @@ package openapi3
 import (
 	"context"
 	"errors"
+	"fmt"
 	"math"
 	"net/url"
 	"strings"
@@ -128,7 +129,17 @@ func (server *Server) Validate(c context.Context) (err error) {
 	if server.URL == "" {
 		return errors.New("value of url must be a non-empty string")
 	}
-	for _, v := range server.Variables {
+	opening, closing := strings.Count(server.URL, "{"), strings.Count(server.URL, "}")
+	if opening != closing {
+		return errors.New("server URL has mismatched { and }")
+	}
+	if opening != len(server.Variables) {
+		return errors.New("server has undeclared variables")
+	}
+	for name, v := range server.Variables {
+		if !strings.Contains(server.URL, fmt.Sprintf("{%s}", name)) {
+			return errors.New("server has undeclared variables")
+		}
 		if err = v.Validate(c); err != nil {
 			return
 		}
@@ -154,7 +165,7 @@ func (serverVariable *ServerVariable) UnmarshalJSON(data []byte) error {
 
 func (serverVariable *ServerVariable) Validate(c context.Context) error {
 	switch serverVariable.Default.(type) {
-	case float64, string:
+	case float64, string, nil:
 	default:
 		return errors.New("value of default must be either a number or a string")
 	}

openapi3/swagger_loader_test.go

@@ -1,11 +1,13 @@
 package openapi3
 
 import (
+	"errors"
 	"fmt"
 	"net"
 	"net/http"
 	"net/http/httptest"
 	"net/url"
+	"strings"
 	"testing"
 
 	"github.com/stretchr/testify/require"
@@ -82,8 +84,8 @@ func TestResolveSchemaRef(t *testing.T) {
 	doc, err := loader.LoadSwaggerFromData(source)
 	require.NoError(t, err)
 	err = doc.Validate(loader.Context)
-
 	require.NoError(t, err)
+
 	refAVisited := doc.Components.Schemas["A"].Value.AllOf[0]
 	require.Equal(t, "#/components/schemas/B", refAVisited.Ref)
 	require.NotNil(t, refAVisited.Value)
@@ -267,7 +269,6 @@ func TestLoadFileWithExternalSchemaRef(t *testing.T) {
 	loader.IsExternalRefsAllowed = true
 	swagger, err := loader.LoadSwaggerFromFile("testdata/testref.openapi.json")
 	require.NoError(t, err)
-
 	require.NotNil(t, swagger.Components.Schemas["AnotherTestSchema"].Value.Type)
 }
 
@@ -497,3 +498,33 @@ paths:
 	err = doc.Validate(loader.Context)
 	require.NoError(t, err)
 }
+
+func TestServersVariables(t *testing.T) {
+	const spec = `
+openapi: 3.0.1
+info:
+  title: My API
+  version: 1.0.0
+paths: {}
+servers:
+- @@@
+`
+	for value, expected := range map[string]error{
+		`{url: /}`:                            nil,
+		`{url: "http://{x}.{y}.example.com"}`: errors.New("invalid servers: server has undeclared variables"),
+		`{url: "http://{x}.y}.example.com"}`:  errors.New("invalid servers: server URL has mismatched { and }"),
+		`{url: "http://{x.example.com"}`:      errors.New("invalid servers: server URL has mismatched { and }"),
+		`{url: "http://{x}.example.com", variables: {x: {default: "www"}}}`: nil,
+		`{url: "http://{x}.example.com", variables: {x: {enum: ["www"]}}}`:  nil,
+		`{url: "http://www.example.com", variables: {x: {enum: ["www"]}}}`:  errors.New("invalid servers: server has undeclared variables"),
+		`{url: "http://{y}.example.com", variables: {x: {enum: ["www"]}}}`:  errors.New("invalid servers: server has undeclared variables"),
+	} {
+		t.Run(value, func(t *testing.T) {
+			loader := NewSwaggerLoader()
+			doc, err := loader.LoadSwaggerFromData([]byte(strings.Replace(spec, "@@@", value, 1)))
+			require.NoError(t, err)
+			err = doc.Validate(loader.Context)
+			require.Equal(t, expected, err)
+		})
+	}
+}

openapi3filter/errors.go

@@ -6,15 +6,6 @@ import (
 	"github.com/getkin/kin-openapi/openapi3"
 )
 
-type RouteError struct {
-	Route  Route
-	Reason string
-}
-
-func (err *RouteError) Error() string {
-	return err.Reason
-}
-
 var _ error = &RequestError{}
 
 // RequestError is returned by ValidateRequest when request does not match OpenAPI spec

openapi3filter/req_resp_decoder_test.go

@@ -16,6 +16,7 @@ import (
 	"testing"
 
 	"github.com/getkin/kin-openapi/openapi3"
+	legacyrouter "github.com/getkin/kin-openapi/routers/legacy"
 	"github.com/stretchr/testify/require"
 )
 
@@ -922,10 +923,10 @@ func TestDecodeParameter(t *testing.T) {
 					spec.AddOperation(path, http.MethodGet, op)
 					err = spec.Validate(context.Background())
 					require.NoError(t, err)
-					router := NewRouter()
-					require.NoError(t, router.AddSwagger(spec))
+					router, err := legacyrouter.NewRouter(spec)
+					require.NoError(t, err)
 
-					route, pathParams, err := router.FindRoute(req.Method, req.URL)
+					route, pathParams, err := router.FindRoute(req)
 					require.NoError(t, err)
 
 					input := &RequestValidationInput{Request: req, PathParams: pathParams, Route: route}