optimizing tenant resolution and routing

Oqtane.Server/Infrastructure/TenantManager.cs

@@ -0,0 +1,87 @@
+using System;
+using System.Linq;
+using Microsoft.AspNetCore.Http;
+using Oqtane.Models;
+using Oqtane.Repository;
+using Oqtane.Shared;
+
+namespace Oqtane.Infrastructure
+{
+    public class TenantManager : ITenantManager
+    {
+        private readonly IHttpContextAccessor _httpContextAccessor;
+        private readonly IAliasRepository _aliasRepository;
+        private readonly ITenantRepository _tenantRepository;
+        private readonly SiteState _siteState;
+
+        public TenantManager(IHttpContextAccessor httpContextAccessor, IAliasRepository aliasRepository, ITenantRepository tenantRepository, SiteState siteState)
+        {
+            _httpContextAccessor = httpContextAccessor;
+            _aliasRepository = aliasRepository;
+            _tenantRepository = tenantRepository;
+            _siteState = siteState;
+        }
+
+        public Alias GetAlias()
+        {
+            Alias alias = null;
+
+            if (_siteState != null && _siteState.Alias != null)
+            {
+                alias = _siteState.Alias;
+            }
+            else
+            {
+                // if there is http context
+                if (_httpContextAccessor.HttpContext != null)
+                {
+                    // legacy support for client api requests which would include the alias as a path prefix ( ie. {alias}/api/[controller] )
+                    int aliasId;
+                    string[] segments = _httpContextAccessor.HttpContext.Request.Path.Value.Split(new[] { '/' }, StringSplitOptions.RemoveEmptyEntries);
+                    if (segments.Length > 1 && (segments[1] == "api" || segments[1] == "pages") && int.TryParse(segments[0], out aliasId))
+                    {
+                        alias = _aliasRepository.GetAliases().ToList().FirstOrDefault(item => item.AliasId == aliasId);
+                    }
+
+                    // resolve alias based on host name and path
+                    if (alias == null)
+                    {
+                        string name = _httpContextAccessor.HttpContext.Request.Host.Value + _httpContextAccessor.HttpContext.Request.Path;
+                        alias = _aliasRepository.GetAlias(name);
+                    }
+
+                    // if there is a match save it
+                    if (alias != null)
+                    {
+                        _siteState.Alias = alias;
+                    }
+                }
+            }
+
+            return alias;
+        }
+
+        public Tenant GetTenant()
+        {
+            var alias = GetAlias();
+            if (alias != null)
+            {
+                // return tenant details
+                return _tenantRepository.GetTenants().ToList().FirstOrDefault(item => item.TenantId == alias.TenantId);
+            }
+            return null;
+        }
+
+        public void SetAlias(Alias alias)
+        {
+            // background processes can set the alias using the SiteState service
+            _siteState.Alias = alias;
+        }
+
+        public void SetTenant(int tenantId)
+        {
+            // background processes can set the alias using the SiteState service
+            _siteState.Alias = new Alias { TenantId = tenantId };
+        }
+    }
+}