feat: prepend base server URL to the relative OAuth token path (#52)

.github/workflows/test.yaml

@@ -22,7 +22,8 @@ jobs:
           sleep 5
           go test -v -coverpkg=./... -race -timeout 3m -coverprofile=coverage.out.tmp ./...
           docker compose down -v
-          cat coverage.out.tmp | grep -v "main.go" > coverage.out
+          cat coverage.out.tmp | grep -v "main.go" > coverage.out.tmp2
+          cat coverage.out.tmp2 | grep -v "version.go" > coverage.out
       - name: Run integration tests
         run: |
           ./scripts/test.sh

connector/connector_test.go

@@ -981,6 +981,16 @@ func createMockServer(t *testing.T, apiKey string, bearerToken string) *httptest
 		}
 	})
 
+	mux.HandleFunc("/oauth2/token", func(w http.ResponseWriter, r *http.Request) {
+		switch r.Method {
+		case http.MethodGet, http.MethodPost:
+			w.WriteHeader(http.StatusBadRequest)
+		default:
+			w.WriteHeader(http.StatusMethodNotAllowed)
+			return
+		}
+	})
+
 	return httptest.NewServer(mux)
 }
 
@@ -1150,6 +1160,37 @@ func TestConnectorOAuth(t *testing.T) {
 			},
 		},
 	})
+
+	failureBody := []byte(`{
+		"collection": "findPetsOAuth",
+		"query": {
+			"fields": {
+				"__value": {
+					"type": "column",
+					"column": "__value"
+				}
+			}
+		},
+		"arguments": {
+			"httpOptions": {
+				"type": "literal",
+				"value": {
+					"servers": ["1"]
+				}
+			}
+		},
+		"collection_relationships": {}
+	}`)
+
+	res, err = http.Post(fmt.Sprintf("%s/query", testServer.URL), "application/json", bytes.NewBuffer(failureBody))
+	assert.NilError(t, err)
+	defer res.Body.Close()
+
+	assert.Equal(t, http.StatusInternalServerError, res.StatusCode)
+
+	respBody, err := io.ReadAll(res.Body)
+	assert.NilError(t, err)
+	assert.Assert(t, strings.Contains(string(respBody), "oauth2: cannot fetch token: 400 Bad Request"))
 }
 
 type mockTLSServer struct {

connector/internal/client.go

@@ -282,7 +282,7 @@ func (client *HTTPClient) doRequest(ctx context.Context, request *RetryableReque
 	ctx, span := tracer.Start(ctx, fmt.Sprintf("%s %s", method, request.RawRequest.URL), trace.WithSpanKind(trace.SpanKindClient))
 	defer span.End()
 
-	urlAttr := cloneURL(&request.URL)
+	urlAttr := restUtils.CloneURL(&request.URL)
 	password, hasPassword := urlAttr.User.Password()
 	if urlAttr.User.String() != "" || hasPassword {
 		maskedUser := restUtils.MaskString(urlAttr.User.Username())

connector/internal/security/auth.go

@@ -4,6 +4,7 @@ import (
 	"context"
 	"errors"
 	"net/http"
+	"net/url"
 
 	"github.com/hasura/ndc-http/ndc-http-schema/schema"
 )
@@ -19,7 +20,7 @@ type Credential interface {
 }
 
 // NewCredential creates a generic credential from the security scheme.
-func NewCredential(ctx context.Context, httpClient *http.Client, security schema.SecurityScheme) (Credential, bool, error) {
+func NewCredential(ctx context.Context, httpClient *http.Client, baseServerURL *url.URL, security schema.SecurityScheme) (Credential, bool, error) {
 	if security.SecuritySchemer == nil {
 		return nil, false, errors.New("empty security scheme")
 	}
@@ -44,7 +45,7 @@ func NewCredential(ctx context.Context, httpClient *http.Client, security schema
 				headerForwardingRequired = true
 			}
 
-			cred, err := NewOAuth2Client(ctx, httpClient, flowType, &flow)
+			cred, err := NewOAuth2Client(ctx, httpClient, baseServerURL, flowType, &flow)
 
 			return cred, headerForwardingRequired || err != nil, err
 		}

connector/internal/security/oauth2.go

@@ -5,8 +5,10 @@ import (
 	"fmt"
 	"net/http"
 	"net/url"
+	"path"
 
 	"github.com/hasura/ndc-http/ndc-http-schema/schema"
+	"github.com/hasura/ndc-http/ndc-http-schema/utils"
 	"golang.org/x/oauth2"
 	"golang.org/x/oauth2/clientcredentials"
 )
@@ -20,23 +22,38 @@ type OAuth2Client struct {
 var _ Credential = &OAuth2Client{}
 
 // NewOAuth2Client creates an OAuth2 client from the security scheme
-func NewOAuth2Client(ctx context.Context, httpClient *http.Client, flowType schema.OAuthFlowType, config *schema.OAuthFlow) (*OAuth2Client, error) {
+func NewOAuth2Client(ctx context.Context, httpClient *http.Client, baseServerURL *url.URL, flowType schema.OAuthFlowType, config *schema.OAuthFlow) (*OAuth2Client, error) {
 	if flowType != schema.ClientCredentialsFlow || config.TokenURL == nil || config.ClientID == nil || config.ClientSecret == nil {
 		return &OAuth2Client{
 			client:  httpClient,
 			isEmpty: true,
 		}, nil
 	}
 
-	tokenURL, err := config.TokenURL.Get()
+	rawTokenURL, err := config.TokenURL.Get()
 	if err != nil {
 		return nil, fmt.Errorf("tokenUrl: %w", err)
 	}
 
-	if _, err := schema.ParseRelativeOrHttpURL(tokenURL); err != nil {
+	tokenURL, err := schema.ParseRelativeOrHttpURL(rawTokenURL)
+	if err != nil {
 		return nil, fmt.Errorf("tokenUrl: %w", err)
 	}
 
+	// if the token URL is a relative path it will be joined with the base server URL
+	if tokenURL.Host == "" {
+		tu := utils.CloneURL(baseServerURL)
+		tu.Path = path.Join(tu.Path, tokenURL.Path)
+		q := tu.Query()
+		for k, v := range tokenURL.Query() {
+			q[k] = v
+		}
+		tu.RawQuery = q.Encode()
+		tu.RawFragment = tokenURL.RawFragment
+
+		tokenURL = tu
+	}
+
 	scopes := make([]string, 0, len(config.Scopes))
 	for scope := range config.Scopes {
 		scopes = append(scopes, scope)
@@ -68,7 +85,7 @@ func NewOAuth2Client(ctx context.Context, httpClient *http.Client, flowType sche
 		ClientID:       clientID,
 		ClientSecret:   clientSecret,
 		Scopes:         scopes,
-		TokenURL:       tokenURL,
+		TokenURL:       tokenURL.String(),
 		EndpointParams: endpointParams,
 	}
 

connector/internal/upstream.go

@@ -5,6 +5,7 @@ import (
 	"fmt"
 	"log/slog"
 	"net/http"
+	"net/url"
 	"strconv"
 
 	"github.com/hasura/ndc-http/connector/internal/argument"
@@ -58,12 +59,12 @@ func (um *UpstreamManager) Register(ctx context.Context, runtimeSchema *configur
 		}
 	}
 
+	var defaultServerURL *url.URL
 	settings := UpstreamSetting{
-		servers:     make(map[string]Server),
-		security:    runtimeSchema.Settings.Security,
-		headers:     um.getHeadersFromEnv(logger, namespace, runtimeSchema.Settings.Headers),
-		credentials: um.registerSecurityCredentials(ctx, httpClient, runtimeSchema.Settings.SecuritySchemes, logger.With(slog.String("namespace", namespace))),
-		httpClient:  httpClient,
+		servers:    make(map[string]Server),
+		security:   runtimeSchema.Settings.Security,
+		headers:    um.getHeadersFromEnv(logger, namespace, runtimeSchema.Settings.Headers),
+		httpClient: httpClient,
 	}
 
 	if len(runtimeSchema.Settings.ArgumentPresets) > 0 {
@@ -89,6 +90,10 @@ func (um *UpstreamManager) Register(ctx context.Context, runtimeSchema *configur
 			continue
 		}
 
+		if defaultServerURL == nil {
+			defaultServerURL = serverURL
+		}
+
 		serverClient := httpClient
 		if server.TLS != nil {
 			tlsClient, err := security.NewHTTPClientTLS(um.defaultClient, server.TLS, logger)
@@ -105,7 +110,7 @@ func (um *UpstreamManager) Register(ctx context.Context, runtimeSchema *configur
 			URL:         serverURL,
 			Headers:     um.getHeadersFromEnv(logger, namespace, server.Headers),
 			Security:    server.Security,
-			Credentials: um.registerSecurityCredentials(ctx, serverClient, server.SecuritySchemes, logger.With(slog.String("namespace", namespace), slog.String("server_id", serverID))),
+			Credentials: um.registerSecurityCredentials(ctx, serverClient, serverURL, server.SecuritySchemes, logger.With(slog.String("namespace", namespace), slog.String("server_id", serverID))),
 			HTTPClient:  serverClient,
 		}
 
@@ -120,6 +125,8 @@ func (um *UpstreamManager) Register(ctx context.Context, runtimeSchema *configur
 		settings.servers[serverID] = newServer
 	}
 
+	settings.credentials = um.registerSecurityCredentials(ctx, httpClient, defaultServerURL, runtimeSchema.Settings.SecuritySchemes, logger.With(slog.String("namespace", namespace)))
+
 	um.upstreams[namespace] = settings
 
 	return nil
@@ -292,11 +299,11 @@ func (um *UpstreamManager) getHeadersFromEnv(logger *slog.Logger, namespace stri
 	return results
 }
 
-func (um *UpstreamManager) registerSecurityCredentials(ctx context.Context, httpClient *http.Client, securitySchemes map[string]rest.SecurityScheme, logger *slog.Logger) map[string]security.Credential {
+func (um *UpstreamManager) registerSecurityCredentials(ctx context.Context, httpClient *http.Client, baseServerURL *url.URL, securitySchemes map[string]rest.SecurityScheme, logger *slog.Logger) map[string]security.Credential {
 	credentials := make(map[string]security.Credential)
 
 	for key, ss := range securitySchemes {
-		cred, headerForwardRequired, err := security.NewCredential(ctx, httpClient, ss)
+		cred, headerForwardRequired, err := security.NewCredential(ctx, httpClient, baseServerURL, ss)
 		if err != nil {
 			// Relax the error to allow schema introspection without environment variables setting.
 			// Moreover, because there are many security schemes the user may use one of them.

connector/internal/utils.go

@@ -2,7 +2,6 @@ package internal
 
 import (
 	"net/http"
-	"net/url"
 	"strings"
 
 	"github.com/hasura/ndc-http/ndc-http-schema/utils"
@@ -52,19 +51,3 @@ func evalForwardedHeaders(req *RetryableRequest, headers map[string]string) erro
 
 	return nil
 }
-
-func cloneURL(input *url.URL) *url.URL {
-	return &url.URL{
-		Scheme:      input.Scheme,
-		Opaque:      input.Opaque,
-		User:        input.User,
-		Host:        input.Host,
-		Path:        input.Path,
-		RawPath:     input.RawPath,
-		OmitHost:    input.OmitHost,
-		ForceQuery:  input.ForceQuery,
-		RawQuery:    input.RawQuery,
-		Fragment:    input.Fragment,
-		RawFragment: input.RawFragment,
-	}
-}

connector/testdata/auth/schema.yaml

@@ -3,6 +3,22 @@ settings:
   servers:
     - url:
         env: PET_STORE_URL
+    - url:
+        env: PET_STORE_URL
+      securitySchemes:
+        petstore_auth:
+          type: oauth2
+          flows:
+            clientCredentials:
+              tokenUrl:
+                value: /oauth2/token
+              clientId:
+                env: OAUTH2_CLIENT_ID
+              clientSecret:
+                env: OAUTH2_CLIENT_SECRET
+              scopes:
+                read:pets: read your pets
+                write:pets: modify pets in your account
   securitySchemes:
     api_key:
       type: apiKey

ndc-http-schema/utils/http.go

@@ -1,6 +1,7 @@
 package utils
 
 import (
+	"net/url"
 	"strings"
 
 	"github.com/hasura/ndc-http/ndc-http-schema/schema"
@@ -30,3 +31,20 @@ func IsContentTypeBinary(contentType string) bool {
 func IsContentTypeMultipartForm(contentType string) bool {
 	return strings.HasPrefix(contentType, "multipart/")
 }
+
+// CloneURL clones the input URL to a new instance.
+func CloneURL(input *url.URL) *url.URL {
+	return &url.URL{
+		Scheme:      input.Scheme,
+		Opaque:      input.Opaque,
+		User:        input.User,
+		Host:        input.Host,
+		Path:        input.Path,
+		RawPath:     input.RawPath,
+		OmitHost:    input.OmitHost,
+		ForceQuery:  input.ForceQuery,
+		RawQuery:    input.RawQuery,
+		Fragment:    input.Fragment,
+		RawFragment: input.RawFragment,
+	}
+}