feat(kv): add frontend redirect configuration.

provider/kv/kv_config.go

@@ -33,6 +33,8 @@ func (p *Provider) buildConfiguration() *types.Configuration {
 		"Last":        p.last,
 		"Has":         p.has,
 
+		// Frontend functions
+		"getRedirect":   p.getRedirect,
 		// Backend functions
 		"getSticky":               p.getSticky,
 		"hasStickinessLabel":      p.hasStickinessLabel,
@@ -77,6 +79,23 @@ func (p *Provider) getStickinessCookieName(rootPath string) string {
 	return p.get("", rootPath, pathBackendLoadBalancerStickinessCookieName)
 }
 
+func (p *Provider) getRedirect(rootPath string) *types.Redirect {
+	if p.has(rootPath, pathFrontendRedirectEntryPoint) {
+		return &types.Redirect{
+			EntryPoint: p.get("", rootPath, pathFrontendRedirectEntryPoint),
+		}
+	}
+
+	if p.has(rootPath, pathFrontendRedirectRegex) && p.has(rootPath, pathFrontendRedirectReplacement) {
+		return &types.Redirect{
+			Regex:       p.get("", rootPath, pathFrontendRedirectRegex),
+			Replacement: p.get("", rootPath, pathFrontendRedirectReplacement),
+		}
+	}
+
+	return nil
+}
+
 func (p *Provider) listServers(backend string) []string {
 	serverNames := p.list(backend, pathBackendServers)
 	return fun.Filter(p.serverFilter, serverNames).([]string)

provider/kv/kv_config_test.go

@@ -707,3 +707,66 @@ func TestProviderHasStickinessLabel(t *testing.T) {
 		})
 	}
 }
+
+func TestProviderGetRedirect(t *testing.T) {
+	testCases := []struct {
+		desc     string
+		rootPath string
+		kvPairs  []*store.KVPair
+		expected *types.Redirect
+	}{
+		{
+			desc:     "should use entry point when entry point key is valued in the store",
+			rootPath: "traefik/frontends/foo",
+			kvPairs: filler("traefik",
+				frontend("foo",
+					withPair(pathFrontendRedirectEntryPoint, "https"))),
+			expected: &types.Redirect{
+				EntryPoint: "https",
+			},
+		},
+		{
+			desc:     "should use regex when regex keys are valued in the store",
+			rootPath: "traefik/frontends/foo",
+			kvPairs: filler("traefik",
+				frontend("foo",
+					withPair(pathFrontendRedirectRegex, "(.*)"),
+					withPair(pathFrontendRedirectReplacement, "$1"))),
+			expected: &types.Redirect{
+				Regex:       "(.*)",
+				Replacement: "$1",
+			},
+		},
+		{
+			desc:     "should only use entry point when entry point and regex base are valued in the store",
+			rootPath: "traefik/frontends/foo",
+			kvPairs: filler("traefik",
+				frontend("foo",
+					withPair(pathFrontendRedirectEntryPoint, "https"),
+					withPair(pathFrontendRedirectRegex, "nope"),
+					withPair(pathFrontendRedirectReplacement, "nope"))),
+			expected: &types.Redirect{
+				EntryPoint: "https",
+			},
+		},
+		{
+			desc:     "should return when redirect keys are not valued in the store",
+			rootPath: "traefik/frontends/foo",
+			kvPairs:  filler("traefik", frontend("foo")),
+			expected: nil,
+		},
+	}
+
+	for _, test := range testCases {
+		test := test
+		t.Run(test.desc, func(t *testing.T) {
+			t.Parallel()
+
+			p := newProviderMock(test.kvPairs)
+
+			actual := p.getRedirect(test.rootPath)
+
+			assert.Equal(t, test.expected, actual)
+		})
+	}
+}

provider/kv/kv_mock_test.go

@@ -7,6 +7,15 @@ import (
 	"github.com/docker/libkv/store"
 )
 
+func newProviderMock(kvPairs []*store.KVPair) *Provider {
+	return &Provider{
+		Prefix: "traefik",
+		kvClient: &Mock{
+			KVPairs: kvPairs,
+		},
+	}
+}
+
 // Override Get/List to return a error
 type KvError struct {
 	Get  error

templates/kv.tmpl

@@ -70,6 +70,14 @@
       "{{.}}",
       {{end}}]
 
+    {{$redirect := getRedirect $frontend }}
+    {{ if $redirect }}
+    [frontends."{{$frontendName}}".redirect]
+      entryPoint = "{{ $redirect.EntryPoint }}"
+      regex = "{{ $redirect.Regex }}"
+      replacement = "{{ $redirect.Replacement }}"
+    {{end}}
+
     {{range $route := List $frontend "/routes/"}}
     [frontends."{{$frontendName}}".routes."{{Last $route}}"]
       rule = "{{Get "" $route "/rule"}}"