Add $host pseudo variable (#544)

This adds support for $host, which behaves similarly to $path. The idea with this is to be able to create a global redirect of anything received on, say, http to the https equivalent of what you were trying to hit. Fixes #533
fabiolb · Sep 12, 2018 · dc67d5a · dc67d5a
1 parent c730093
commit dc67d5a
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Showing 4 changed files with 96 additions and 3 deletions.
diff --git a/proxy/http_integration_test.go b/proxy/http_integration_test.go
@@ -262,7 +262,46 @@ func TestProxyHost(t *testing.T) {
 	})
 }
 
-func TestRedirect(t *testing.T) {
+func TestHostRedirect(t *testing.T) {
+	routes := "route add https-redir *:80 https://$host$path opts \"redirect=301\"\n"
+
+	tbl, _ := route.NewTable(routes)
+
+	proxy := httptest.NewServer(&HTTPProxy{
+		Transport: http.DefaultTransport,
+		Lookup: func(r *http.Request) *route.Target {
+			r.Host = "c.com"
+			return tbl.Lookup(r, "", route.Picker["rr"], route.Matcher["prefix"])
+		},
+	})
+	defer proxy.Close()
+
+	tests := []struct {
+		req      string
+		wantCode int
+		wantLoc  string
+	}{
+		{req: "/baz", wantCode: 301, wantLoc: "https://c.com/baz"},
+	}
+
+	http.DefaultClient.CheckRedirect = func(req *http.Request, via []*http.Request) error {
+		// do not follow redirects
+		return http.ErrUseLastResponse
+	}
+
+	for _, tt := range tests {
+		resp, _ := mustGet(proxy.URL + tt.req)
+		if resp.StatusCode != tt.wantCode {
+			t.Errorf("got status code %d, want %d", resp.StatusCode, tt.wantCode)
+		}
+		gotLoc, _ := resp.Location()
+		if gotLoc.String() != tt.wantLoc {
+			t.Errorf("got location %s, want %s", gotLoc, tt.wantLoc)
+		}
+	}
+}
+
+func TestPathRedirect(t *testing.T) {
 	routes := "route add mock / http://a.com/$path opts \"redirect=301\"\n"
 	routes += "route add mock /foo http://a.com/abc opts \"redirect=301\"\n"
 	routes += "route add mock /bar http://b.com/$path opts \"redirect=302 strip=/bar\"\n"

diff --git a/route/table.go b/route/table.go
@@ -360,6 +360,7 @@ func (t Table) Lookup(req *http.Request, trace string, pick picker, match matche
 	for _, h := range hosts {
 		if target = t.lookup(h, req.URL.Path, trace, pick, match); target != nil {
 			if target.RedirectCode != 0 {
+				req.URL.Host = req.Host
 				target.BuildRedirectURL(req.URL) // build redirect url and cache in target
 				if target.RedirectURL.Scheme == req.Header.Get("X-Forwarded-Proto") &&
 					target.RedirectURL.Host == req.Host &&

diff --git a/route/target.go b/route/target.go
@@ -85,4 +85,7 @@ func (t *Target) BuildRedirectURL(requestURL *url.URL) {
 	if t.RedirectURL.Path == "" {
 		t.RedirectURL.Path = "/"
 	}
+	if strings.Contains(t.RedirectURL.Host, "$host") {
+		t.RedirectURL.Host = strings.Replace(t.RedirectURL.Host, "$host", requestURL.Host, 1)
+	}
 }
diff --git a/route/target_test.go b/route/target_test.go
@@ -32,6 +32,16 @@ func TestTarget_BuildRedirectURL(t *testing.T) {
 				{req: "/?aaa=1", want: "http://bar.com/a/b/c?foo=bar"},
 			},
 		},
+		{ // simple http -> https redirect with static path
+			route: "route add redirect *:80/ https://$host/",
+			tests: []routeTest{
+				{req: "/", want: "https://foo.com/"},
+				{req: "/abc", want: "https://foo.com/"},
+				{req: "/a/b/c", want: "https://foo.com/"},
+				{req: "/?aaa=1", want: "https://foo.com/"},
+				{req: "/abc/?aaa=1", want: "https://foo.com/"},
+			},
+		},
 		{ // simple redirect to corresponding path
 			route: "route add svc / http://bar.com/$path",
 			tests: []routeTest{
@@ -42,7 +52,17 @@ func TestTarget_BuildRedirectURL(t *testing.T) {
 				{req: "/abc/?aaa=1", want: "http://bar.com/abc/?aaa=1"},
 			},
 		},
-		{ // same as above but without / before $path
+		{ // simple http -> https redirect to corresponding host & path
+			route: "route add redirect *:80/ https://$host/$path",
+			tests: []routeTest{
+				{req: "/", want: "https://foo.com/"},
+				{req: "/abc", want: "https://foo.com/abc"},
+				{req: "/a/b/c", want: "https://foo.com/a/b/c"},
+				{req: "/?aaa=1", want: "https://foo.com/?aaa=1"},
+				{req: "/abc/?aaa=1", want: "https://foo.com/abc/?aaa=1"},
+			},
+		},
+		{ // simple redirect to corresponding path without / before $path
 			route: "route add svc / http://bar.com$path",
 			tests: []routeTest{
 				{req: "/", want: "http://bar.com/"},
@@ -52,6 +72,16 @@ func TestTarget_BuildRedirectURL(t *testing.T) {
 				{req: "/abc/?aaa=1", want: "http://bar.com/abc/?aaa=1"},
 			},
 		},
+		{ // simple http -> https redirect to corresponding host & path without / before $path
+			route: "route add redirect *:80/ https://$host$path",
+			tests: []routeTest{
+				{req: "/", want: "https://foo.com/"},
+				{req: "/abc", want: "https://foo.com/abc"},
+				{req: "/a/b/c", want: "https://foo.com/a/b/c"},
+				{req: "/?aaa=1", want: "https://foo.com/?aaa=1"},
+				{req: "/abc/?aaa=1", want: "https://foo.com/abc/?aaa=1"},
+			},
+		},
 		{ // arbitrary subdir on target with $path at end
 			route: "route add svc / http://bar.com/bbb/$path",
 			tests: []routeTest{
@@ -62,7 +92,17 @@ func TestTarget_BuildRedirectURL(t *testing.T) {
 				{req: "/abc/?aaa=1", want: "http://bar.com/bbb/abc/?aaa=1"},
 			},
 		},
-		{ // same as above but without / before $path
+		{ // http -> https redir to corresonding host w/ arbitrary subdir on target with $path at end
+			route: "route add redirect *:80/ https://$host/bbb/$path",
+			tests: []routeTest{
+				{req: "/", want: "https://foo.com/bbb/"},
+				{req: "/abc", want: "https://foo.com/bbb/abc"},
+				{req: "/a/b/c", want: "https://foo.com/bbb/a/b/c"},
+				{req: "/?aaa=1", want: "https://foo.com/bbb/?aaa=1"},
+				{req: "/abc/?aaa=1", want: "https://foo.com/bbb/abc/?aaa=1"},
+			},
+		},
+		{ // arbitrary subdir on target with $path at end but without / before $path
 			route: "route add svc / http://bar.com/bbb$path",
 			tests: []routeTest{
 				{req: "/", want: "http://bar.com/bbb/"},
@@ -72,6 +112,16 @@ func TestTarget_BuildRedirectURL(t *testing.T) {
 				{req: "/abc/?aaa=1", want: "http://bar.com/bbb/abc/?aaa=1"},
 			},
 		},
+		{ // http -> https redir to corresonding host w/ arbitrary subdir on target with $path at end but without / before $path
+			route: "route add redirect *:80/ https://$host/bbb$path",
+			tests: []routeTest{
+				{req: "/", want: "https://foo.com/bbb/"},
+				{req: "/abc", want: "https://foo.com/bbb/abc"},
+				{req: "/a/b/c", want: "https://foo.com/bbb/a/b/c"},
+				{req: "/?aaa=1", want: "https://foo.com/bbb/?aaa=1"},
+				{req: "/abc/?aaa=1", want: "https://foo.com/bbb/abc/?aaa=1"},
+			},
+		},
 		{ // strip prefix
 			route: "route add svc /stripme http://bar.com/$path opts \"strip=/stripme\"",
 			tests: []routeTest{