XYZ-59: Implement redis caching layer for Role store. (#8207)

* XYZ-59: Implement redis caching layer for Role store.

* Use variable for key where used more than once.

store/redis_supplier_roles.go

@@ -0,0 +1,89 @@
+// Copyright (c) 2016-present Mattermost, Inc. All Rights Reserved.
+// See License.txt for license information.
+
+package store
+
+import (
+	"context"
+	"fmt"
+
+	l4g "github.com/alecthomas/log4go"
+
+	"github.com/mattermost/mattermost-server/model"
+)
+
+func (s *RedisSupplier) RoleSave(ctx context.Context, role *model.Role, hints ...LayeredStoreHint) *LayeredStoreSupplierResult {
+	key := buildRedisKeyForRoleName(role.Name)
+
+	if err := s.client.Del(key).Err(); err != nil {
+		l4g.Error("Redis failed to remove key " + key + " Error: " + err.Error())
+	}
+
+	return s.Next().RoleSave(ctx, role, hints...)
+}
+
+func (s *RedisSupplier) RoleGet(ctx context.Context, roleId string, hints ...LayeredStoreHint) *LayeredStoreSupplierResult {
+	// Roles are cached by name, as that is most commonly how they are looked up.
+	// This means that no caching is supported on roles being looked up by ID.
+	return s.Next().RoleGet(ctx, roleId, hints...)
+}
+
+func (s *RedisSupplier) RoleGetByName(ctx context.Context, name string, hints ...LayeredStoreHint) *LayeredStoreSupplierResult {
+	key := buildRedisKeyForRoleName(name)
+
+	var role *model.Role
+	found, err := s.load(key, &role)
+	if err != nil {
+		l4g.Error("Redis encountered an error on read: " + err.Error())
+	} else if found {
+		result := NewSupplierResult()
+		result.Data = role
+		return result
+	}
+
+	result := s.Next().RoleGetByName(ctx, name, hints...)
+
+	if result.Err == nil {
+		if err := s.save(key, result.Data, REDIS_EXPIRY_TIME); err != nil {
+			l4g.Error("Redis encountered and error on write: " + err.Error())
+		}
+	}
+
+	return result
+}
+
+func (s *RedisSupplier) RoleGetByNames(ctx context.Context, roleNames []string, hints ...LayeredStoreHint) *LayeredStoreSupplierResult {
+	var foundRoles []*model.Role
+	var rolesToQuery []string
+
+	for _, roleName := range roleNames {
+		var role *model.Role
+		found, err := s.load(buildRedisKeyForRoleName(roleName), &role)
+		if err == nil && found {
+			foundRoles = append(foundRoles, role)
+		} else {
+			rolesToQuery = append(rolesToQuery, roleName)
+			if err != nil {
+				l4g.Error("Redis encountered an error on read: " + err.Error())
+			}
+		}
+	}
+
+	result := s.Next().RoleGetByNames(ctx, rolesToQuery, hints...)
+
+	if result.Err == nil {
+		rolesFound := result.Data.([]*model.Role)
+		for _, role := range rolesFound {
+			if err := s.save(buildRedisKeyForRoleName(role.Name), role, REDIS_EXPIRY_TIME); err != nil {
+				l4g.Error("Redis encountered and error on write: " + err.Error())
+			}
+		}
+		result.Data = append(foundRoles, result.Data.([]*model.Role)...)
+	}
+
+	return result
+}
+
+func buildRedisKeyForRoleName(roleName string) string {
+	return fmt.Sprintf("roles:%s", roleName)
+}