Redirect to unique domain

8 files changed, 258 insertions, 7 deletions

diff --git a/app.go b/app.go
index f35df26c..96aa084b 100644
--- a/app.go
+++ b/app.go
@@ -40,6 +40,7 @@ import (
 	"gitlab.com/gitlab-org/gitlab-pages/internal/source"
 	"gitlab.com/gitlab-org/gitlab-pages/internal/source/gitlab"
 	"gitlab.com/gitlab-org/gitlab-pages/internal/tls"
+	"gitlab.com/gitlab-org/gitlab-pages/internal/uniqueDomain"
 	"gitlab.com/gitlab-org/gitlab-pages/internal/urilimiter"
 	"gitlab.com/gitlab-org/gitlab-pages/metrics"
 )
@@ -133,6 +134,7 @@ func setRequestScheme(r *http.Request) *http.Request {
 func (a *theApp) buildHandlerPipeline() (http.Handler, error) {
 	// Handlers should be applied in a reverse order
 	handler := a.serveFileOrNotFoundHandler()
+	handler = uniqueDomain.NewMiddleware(handler)
 	handler = a.Auth.AuthorizationMiddleware(handler)
 	handler = routing.NewMiddleware(handler, a.source)
 
diff --git a/internal/serving/lookup_path.go b/internal/serving/lookup_path.go
index 421e2a51..6a283b6e 100644
--- a/internal/serving/lookup_path.go
+++ b/internal/serving/lookup_path.go
@@ -10,4 +10,5 @@ type LookupPath struct {
 	IsHTTPSOnly        bool
 	HasAccessControl   bool
 	ProjectID          uint64
+	UniqueHost         string
 }
diff --git a/internal/source/gitlab/api/lookup_path.go b/internal/source/gitlab/api/lookup_path.go
index 834767bd..a61d2f7c 100644
--- a/internal/source/gitlab/api/lookup_path.go
+++ b/internal/source/gitlab/api/lookup_path.go
@@ -7,6 +7,7 @@ type LookupPath struct {
 	HTTPSOnly     bool   `json:"https_only,omitempty"`
 	Prefix        string `json:"prefix,omitempty"`
 	Source        Source `json:"source,omitempty"`
+	UniqueHost    string `json:"unique_host,omitempty"`
 }
 
 // Source describes GitLab Page serving variant
diff --git a/internal/source/gitlab/factory.go b/internal/source/gitlab/factory.go
index 312d09bf..1c5d15f5 100644
--- a/internal/source/gitlab/factory.go
+++ b/internal/source/gitlab/factory.go
@@ -31,6 +31,7 @@ func fabricateLookupPath(size int, lookup api.LookupPath) *serving.LookupPath {
 		IsHTTPSOnly:        lookup.HTTPSOnly,
 		HasAccessControl:   lookup.AccessControl,
 		ProjectID:          uint64(lookup.ProjectID),
+		UniqueHost:         lookup.UniqueHost,
 	}
 }
 
diff --git a/internal/uniqueDomain/middleware.go b/internal/uniqueDomain/middleware.go
new file mode 100644
index 00000000..b0af761a
--- /dev/null
+++ b/internal/uniqueDomain/middleware.go
@@ -0,0 +1,74 @@
+package uniqueDomain
+
+import (
+	"net"
+	"net/http"
+	"strings"
+
+	"gitlab.com/gitlab-org/gitlab-pages/internal/domain"
+	"gitlab.com/gitlab-org/gitlab-pages/internal/logging"
+)
+
+func NewMiddleware(handler http.Handler) http.Handler {
+	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		uniqueURL := getUniqueURL(r)
+		if uniqueURL == "" {
+			logging.
+				LogRequest(r).
+				WithField("uniqueURL", uniqueURL).
+				Debug("unique domain: doing nothing")
+
+			handler.ServeHTTP(w, r)
+			return
+		}
+
+		logging.
+			LogRequest(r).
+			WithField("uniqueURL", uniqueURL).
+			Info("redirecting to unique domain")
+
+		http.Redirect(w, r, uniqueURL, http.StatusPermanentRedirect)
+	})
+}
+
+func getUniqueURL(r *http.Request) string {
+	domain := domain.FromRequest(r)
+	lookupPath, err := domain.GetLookupPath(r)
+	if err != nil {
+		logging.
+			LogRequest(r).
+			WithError(err).
+			Error("uniqueDomain: failed to get lookupPath")
+		return ""
+	}
+
+	// No uniqueHost to redirect
+	if lookupPath.UniqueHost == "" {
+		return ""
+	}
+
+	requestHost, port, err := net.SplitHostPort(r.Host)
+	if err != nil {
+		requestHost = r.Host
+	}
+
+	// Already serving the uniqueHost
+	if lookupPath.UniqueHost == requestHost {
+		return ""
+	}
+
+	uniqueURL := *r.URL
+	if port == "" {
+		uniqueURL.Host = lookupPath.UniqueHost
+	} else {
+		uniqueURL.Host = net.JoinHostPort(lookupPath.UniqueHost, port)
+	}
+
+	// Ensure to redirect to the same path requested
+	uniqueURL.Path = strings.TrimPrefix(
+		r.URL.Path,
+		strings.TrimSuffix(lookupPath.Prefix, "/"),
+	)
+
+	return uniqueURL.String()
+}
diff --git a/test/acceptance/uniqueDomain_test.go b/test/acceptance/uniqueDomain_test.go
new file mode 100644
index 00000000..1f423170
--- /dev/null
+++ b/test/acceptance/uniqueDomain_test.go
@@ -0,0 +1,97 @@
+package acceptance_test
+
+import (
+	"net/http"
+	"testing"
+
+	"github.com/stretchr/testify/require"
+
+	"gitlab.com/gitlab-org/gitlab-pages/internal/testhelpers"
+)
+
+func TestRedirectToUniqueDomain(t *testing.T) {
+	RunPagesProcess(t)
+
+	tests := []struct {
+		name          string
+		requestDomain string
+		requestPath   string
+		redirectURL   string
+		httpStatus    int
+	}{
+		{
+			name:          "when project has unique domain",
+			requestDomain: "group.unique-url.gitlab-example.com",
+			requestPath:   "with-unique-url/",
+			redirectURL:   "https://unique-url-group-unique-url-a1b2c3d4e5f6.gitlab-example.com/",
+			httpStatus:    http.StatusPermanentRedirect,
+		},
+		{
+			name:          "when requesting implicit index.html",
+			requestDomain: "group.unique-url.gitlab-example.com",
+			requestPath:   "with-unique-url",
+			redirectURL:   "https://unique-url-group-unique-url-a1b2c3d4e5f6.gitlab-example.com",
+			httpStatus:    http.StatusPermanentRedirect,
+		},
+		{
+			name:          "when project is nested",
+			requestDomain: "group.unique-url.gitlab-example.com",
+			requestPath:   "subgroup1/subgroup2/with-unique-url/subdir/index.html",
+			redirectURL:   "https://unique-url-group-unique-url-a1b2c3d4e5f6.gitlab-example.com/subdir/index.html",
+			httpStatus:    http.StatusPermanentRedirect,
+		},
+		{
+			name:          "when serving with a port",
+			requestDomain: "group.unique-url.gitlab-example.com:8080",
+			requestPath:   "with-unique-url/",
+			redirectURL:   "https://unique-url-group-unique-url-a1b2c3d4e5f6.gitlab-example.com:8080/",
+			httpStatus:    http.StatusPermanentRedirect,
+		},
+		{
+			name:          "when serving a path with a port",
+			requestDomain: "group.unique-url.gitlab-example.com:8080",
+			requestPath:   "with-unique-url/subdir/index.html",
+			redirectURL:   "https://unique-url-group-unique-url-a1b2c3d4e5f6.gitlab-example.com:8080/subdir/index.html",
+			httpStatus:    http.StatusPermanentRedirect,
+		},
+		{
+			name:          "when already serving the unique domain",
+			requestDomain: "unique-url-group-unique-url-a1b2c3d4e5f6.gitlab-example.com",
+			httpStatus:    http.StatusOK,
+		},
+		{
+			name:          "when already serving the unique domain with a port",
+			requestDomain: "unique-url-group-unique-url-a1b2c3d4e5f6.gitlab-example.com:8080",
+			httpStatus:    http.StatusOK,
+		},
+		{
+			name:          "when already serving the unique domain with path",
+			requestDomain: "unique-url-group-unique-url-a1b2c3d4e5f6.gitlab-example.com",
+			requestPath:   "subdir/index.html",
+			httpStatus:    http.StatusOK,
+		},
+		{
+			name:          "when project does not have unique domain with a path",
+			requestDomain: "group.unique-url.gitlab-example.com",
+			requestPath:   "without-unique-url/subdir/index.html",
+			httpStatus:    http.StatusOK,
+		},
+		{
+			name:          "when project does not exist",
+			requestDomain: "group.unique-url.gitlab-example.com",
+			requestPath:   "inexisting-project/",
+			httpStatus:    http.StatusNotFound,
+		},
+	}
+
+	for _, test := range tests {
+		t.Run(test.name, func(t *testing.T) {
+			rsp, err := GetRedirectPage(t, httpsListener, test.requestDomain, test.requestPath)
+			require.NoError(t, err)
+			testhelpers.Close(t, rsp.Body)
+
+			require.Equal(t, test.httpStatus, rsp.StatusCode)
+			require.Equal(t, test.redirectURL, rsp.Header.Get("Location"))
+		})
+	}
+}
diff --git a/test/gitlabstub/api_responses.go b/test/gitlabstub/api_responses.go
index 93bc8995..b9459160 100644
--- a/test/gitlabstub/api_responses.go
+++ b/test/gitlabstub/api_responses.go
@@ -14,6 +14,15 @@ import (
 
 type responseFn func(string) api.VirtualDomain
 
+type projectConfig struct {
+	// refer to makeGitLabPagesAccessStub for custom HTTP responses per projectID
+	projectID     int
+	accessControl bool
+	https         bool
+	pathOnDisk    string
+	uniqueHost    string
+}
+
 // domainResponses holds the predefined API responses for certain domains
 // that can be used with the GitLab API stub in acceptance tests
 // Assume the working dir is inside shared/pages/
@@ -114,6 +123,43 @@ var domainResponses = map[string]responseFn{
 		projectID:  1008,
 		pathOnDisk: "group.acme/with.redirects",
 	}),
+	"group.unique-url.gitlab-example.com": generateVirtualDomain(map[string]projectConfig{
+		"/with-unique-url": {
+			uniqueHost: "unique-url-group-unique-url-a1b2c3d4e5f6.gitlab-example.com",
+			pathOnDisk: "group/project",
+		},
+		"/subgroup1/subgroup2/with-unique-url": {
+			uniqueHost: "unique-url-group-unique-url-a1b2c3d4e5f6.gitlab-example.com",
+			pathOnDisk: "group/project",
+		},
+		"/with-unique-url-with-port": {
+			uniqueHost: "unique-url-group-unique-url-a1b2c3d4e5f6.gitlab-example.com",
+			pathOnDisk: "group/project",
+		},
+		"/with-malformed-unique-url": {
+			uniqueHost: "unique-url@gitlab-example.com:",
+			pathOnDisk: "group/project",
+		},
+		"/with-different-protocol": {
+			uniqueHost: "unique-url-group-unique-url-a1b2c3d4e5f6.gitlab-example.com",
+			pathOnDisk: "group/project",
+		},
+		"/without-unique-url": {
+			pathOnDisk: "group/project",
+		},
+	}),
+	"unique-url-group-unique-url-a1b2c3d4e5f6.gitlab-example.com": generateVirtualDomain(map[string]projectConfig{
+		"/": {
+			uniqueHost: "unique-url-group-unique-url-a1b2c3d4e5f6.gitlab-example.com",
+			pathOnDisk: "group/project",
+		},
+	}),
+	"unique-url-group-unique-url-a1b2c3d4e5f6.gitlab-example.com:8080": generateVirtualDomain(map[string]projectConfig{
+		"/": {
+			uniqueHost: "unique-url-group-unique-url-a1b2c3d4e5f6.gitlab-example.com",
+			pathOnDisk: "group/project",
+		},
+	}),
 	// NOTE: before adding more domains here, generate the zip archive by running (per project)
 	// make zip PROJECT_SUBDIR=group/serving
 	// make zip PROJECT_SUBDIR=group/project2
@@ -187,6 +233,7 @@ func generateVirtualDomainFromDir(dir, rootDomain string, perPrefixConfig map[st
 					Path:   sourcePath,
 					SHA256: sha,
 				},
+				UniqueHost: cfg.uniqueHost,
 			}
 
 			lookupPaths = append(lookupPaths, lookupPath)
@@ -198,12 +245,39 @@ func generateVirtualDomainFromDir(dir, rootDomain string, perPrefixConfig map[st
 	}
 }
 
-type projectConfig struct {
-	// refer to makeGitLabPagesAccessStub for custom HTTP responses per projectID
-	projectID     int
-	accessControl bool
-	https         bool
-	pathOnDisk    string
+func generateVirtualDomain(projectConfigs map[string]projectConfig) responseFn {
+	return func(wd string) api.VirtualDomain {
+		nextID := 1000
+		lookupPaths := make([]api.LookupPath, 0, len(projectConfigs))
+
+		for project, config := range projectConfigs {
+			if config.projectID == 0 {
+				config.projectID = nextID
+				nextID++
+			}
+
+			sourcePath := fmt.Sprintf("file://%s/%s/public.zip", wd, config.pathOnDisk)
+			sum := sha256.Sum256([]byte(sourcePath))
+			sha := hex.EncodeToString(sum[:])
+
+			lookupPaths = append(lookupPaths, api.LookupPath{
+				ProjectID:     config.projectID,
+				AccessControl: config.accessControl,
+				HTTPSOnly:     config.https,
+				Prefix:        ensureEndingSlash(project),
+				UniqueHost:    config.uniqueHost,
+				Source: api.Source{
+					Type:   "zip",
+					Path:   sourcePath,
+					SHA256: sha,
+				},
+			})
+		}
+
+		return api.VirtualDomain{
+			LookupPaths: lookupPaths,
+		}
+	}
 }
 
 // customDomain with per project config
@@ -230,6 +304,7 @@ func customDomain(config projectConfig) responseFn {
 						SHA256: sha,
 						Path:   sourcePath,
 					},
+					UniqueHost: config.uniqueHost,
 				},
 			},
 		}
diff --git a/test/gitlabstub/handlers.go b/test/gitlabstub/handlers.go
index df09d914..8089277b 100644
--- a/test/gitlabstub/handlers.go
+++ b/test/gitlabstub/handlers.go
@@ -29,7 +29,7 @@ func defaultAPIHandler(delay time.Duration, pagesRoot string) http.HandlerFunc {
 		// check if predefined response exists
 		if responseFn, ok := domainResponses[domain]; ok {
 			if err := json.NewEncoder(w).Encode(responseFn(pagesRoot)); err != nil {
-				log.Fatal(err)
+				log.Fatalf("fail to encode response for domain %q: %v", domain, err)
 			}
 			return
 		}