From 149e50199c5b6a6008d91301dd21d96fdab5629a Mon Sep 17 00:00:00 2001
From: ElectroNafta <atanas.janeshliev@proton.ch>
Date: Thu, 8 Aug 2024 16:56:10 +0200
Subject: [PATCH] feat(BRIDGE-119): added feature flag relevant API calls;
 added Feature Flag route to fake server

---
 client_features.go        | 19 +++++++++++++++++++
 manager_features.go       | 26 ++++++++++++++++++++++++++
 server/backend/api.go     | 21 +++++++++++++++++++++
 server/backend/backend.go |  2 ++
 server/features.go        | 17 +++++++++++++++++
 server/router.go          |  3 +++
 server/server.go          |  8 ++++++++
 7 files changed, 96 insertions(+)
 create mode 100644 client_features.go
 create mode 100644 manager_features.go
 create mode 100644 server/features.go

diff --git a/client_features.go b/client_features.go
new file mode 100644
index 0000000..d41a3b8
--- /dev/null
+++ b/client_features.go
@@ -0,0 +1,19 @@
+package proton
+
+import (
+	"context"
+
+	"github.com/go-resty/resty/v2"
+)
+
+func (c *Client) GetFeatures(ctx context.Context) (FeatureFlagResult, error) {
+	res := FeatureFlagResult{}
+
+	if err := c.do(ctx, func(r *resty.Request) (*resty.Response, error) {
+		return r.SetResult(&res).Get("/feature/v2/frontend")
+	}); err != nil {
+		return FeatureFlagResult{}, err
+	}
+
+	return res, nil
+}
diff --git a/manager_features.go b/manager_features.go
new file mode 100644
index 0000000..7e8f186
--- /dev/null
+++ b/manager_features.go
@@ -0,0 +1,26 @@
+package proton
+
+import (
+	"context"
+)
+
+type FeatureFlagResult struct {
+	Code    int             `json:"Code"`
+	Toggles []FeatureToggle `json:"toggles"`
+}
+
+type FeatureToggle struct {
+	Name    string `json:"name"`
+	Enabled bool   `json:"enabled"`
+}
+
+func (m *Manager) GetFeatures(ctx context.Context) (FeatureFlagResult, error) {
+	responseData := FeatureFlagResult{}
+
+	_, err := m.r(ctx).SetResult(&responseData).Get("/feature/v2/frontend")
+	if err != nil {
+		return FeatureFlagResult{}, err
+	}
+
+	return responseData, nil
+}
diff --git a/server/backend/api.go b/server/backend/api.go
index 1008ff9..431f9a8 100644
--- a/server/backend/api.go
+++ b/server/backend/api.go
@@ -1294,6 +1294,27 @@ func (b *Backend) GenerateContactID(userID string) (string, error) {
 	})
 }
 
+func (b *Backend) GetFeatureFlags() []proton.FeatureToggle {
+	return readBackendRet(b, func(b *unsafeBackend) []proton.FeatureToggle {
+		return b.featureFlags
+	})
+}
+
+func (b *Backend) PushFeatureFlag(flagName string) {
+	writeBackend(b, func(b *unsafeBackend) {
+		b.featureFlags = append(b.featureFlags, proton.FeatureToggle{
+			Name:    flagName,
+			Enabled: true,
+		})
+	})
+}
+
+func (b *Backend) DeleteFeatureFlags() {
+	writeBackend(b, func(b *unsafeBackend) {
+		b.featureFlags = []proton.FeatureToggle{}
+	})
+}
+
 func buildEvent(
 	updates []update,
 	addresses map[string]*address,
diff --git a/server/backend/backend.go b/server/backend/backend.go
index 408242d..8ce276b 100644
--- a/server/backend/backend.go
+++ b/server/backend/backend.go
@@ -48,6 +48,8 @@ type unsafeBackend struct {
 	enableDedup bool
 
 	csTicket []string
+
+	featureFlags []proton.FeatureToggle
 }
 
 func readBackendRet[T any](b *Backend, f func(b *unsafeBackend) T) T {
diff --git a/server/features.go b/server/features.go
new file mode 100644
index 0000000..24bc280
--- /dev/null
+++ b/server/features.go
@@ -0,0 +1,17 @@
+package server
+
+import (
+	"net/http"
+
+	"github.com/gin-gonic/gin"
+)
+
+func (s *Server) handleGetFeatures() gin.HandlerFunc {
+	return func(c *gin.Context) {
+		ff := s.b.GetFeatureFlags()
+		c.JSON(http.StatusOK, gin.H{
+			"Code":    1000,
+			"Toggles": ff,
+		})
+	}
+}
diff --git a/server/router.go b/server/router.go
index fe976c1..c149d51 100644
--- a/server/router.go
+++ b/server/router.go
@@ -26,6 +26,9 @@ func initRouter(s *Server) {
 		s.applyRateLimit(),
 	)
 
+	// Feature flag route. Needs to be updated when user specific feature flags are implemented
+	s.r.GET("/feature/v2/frontend", s.handleGetFeatures())
+
 	if core := s.r.Group("/core/v4"); core != nil {
 		// Domains routes don't need authentication.
 		if domains := core.Group("/domains"); domains != nil {
diff --git a/server/server.go b/server/server.go
index 3c5438b..ad516db 100644
--- a/server/server.go
+++ b/server/server.go
@@ -252,3 +252,11 @@ func (s *Server) Close() {
 	s.proxyTransport.CloseIdleConnections()
 	s.s.Close()
 }
+
+func (s *Server) PushFeatureFlag(flagName string) {
+	s.b.PushFeatureFlag(flagName)
+}
+
+func (s *Server) DeleteFeatureFlags() {
+	s.b.DeleteFeatureFlags()
+}