Implemented groundwork for search configuration.

Props/Services/Modules/IShopManager.cs

@@ -0,0 +1,14 @@
+using System.Collections;
+using System.Collections.Generic;
+using System.Threading.Tasks;
+using Props.Models.Search;
+using Props.Shop.Framework;
+
+namespace Props.Services.Modules
+{
+    public interface IShopManager
+    {
+        public IEnumerable<string> AvailableShops();
+        public Task<IList<ProductListing>> Search(string query, SearchOutline searchOutline);
+    }
+}

Props/Services/Modules/LocalShopManager.cs

@@ -0,0 +1,107 @@
+using System;
+using System.Collections.Generic;
+using System.IO;
+using System.Reflection;
+using System.Text.RegularExpressions;
+using System.Threading.Tasks;
+using Microsoft.Extensions.Configuration;
+using Microsoft.Extensions.Logging;
+using Props.Models.Search;
+using Props.Options;
+using Props.Shop.Framework;
+
+namespace Props.Services.Modules
+{
+    public class LocalShopManager : IShopManager
+    {
+        private ILogger<LocalShopManager> logger;
+        private Dictionary<string, IShop> shops;
+        private ModulesOptions options;
+        private IConfiguration configuration;
+        public LocalShopManager(IConfiguration configuration, ILogger<LocalShopManager> logger)
+        {
+            this.configuration = configuration;
+            this.logger = logger;
+            options = configuration.GetSection(ModulesOptions.Modules).Get<ModulesOptions>();
+
+            shops = new Dictionary<string, IShop>();
+            foreach (IShop shop in LoadShops(options.ShopsDir, options.ShopRegex, options.RecursiveLoad))
+            {
+                if (!shops.TryAdd(shop.ShopName, shop))
+                {
+                    logger.LogWarning("Duplicate shop {0} detected. Ignoring the latter.", shop.ShopName);
+                }
+            }
+        }
+
+        public IEnumerable<string> AvailableShops()
+        {
+            return shops.Keys;
+        }
+
+        public async Task<IList<ProductListing>> Search(string query, SearchOutline searchOutline)
+        {
+            List<ProductListing> results = new List<ProductListing>();
+            foreach (string shopName in shops.Keys)
+            {
+                if (!searchOutline.Disabled[shopName])
+                {
+                    int amount = 0;
+                    await foreach (ProductListing product in shops[shopName].Search(query, searchOutline.Filters))
+                    {
+                        if (searchOutline.Filters.Validate(product))
+                        {
+                            amount += 1;
+                            results.Add(product);
+                        }
+                        if (amount >= options.MaxResults) break;
+                    }
+                }
+            }
+            return results;
+        }
+
+        private IEnumerable<IShop> LoadShops(string shopsDir, string shopRegex, bool recursiveLoad)
+        {
+            Stack<string> directories = new Stack<string>();
+            directories.Push(shopsDir);
+            string currentDirectory = null;
+            while (directories.TryPop(out currentDirectory))
+            {
+                if (recursiveLoad)
+                {
+                    foreach (string dir in Directory.EnumerateDirectories(currentDirectory))
+                    {
+                        directories.Push(dir);
+                    }
+                }
+
+                foreach (string file in Directory.EnumerateFiles(currentDirectory))
+                {
+                    if (Path.GetExtension(file).Equals(".dll") && Regex.IsMatch(file, shopRegex))
+                    {
+                        ShopAssemblyLoadContext context = new ShopAssemblyLoadContext(file);
+                        Assembly assembly = context.LoadFromAssemblyName(new AssemblyName(Path.GetFileNameWithoutExtension(file)));
+                        int success = 0;
+                        foreach (Type type in assembly.GetTypes())
+                        {
+                            if (typeof(IShop).IsAssignableFrom(type))
+                            {
+                                IShop shop = Activator.CreateInstance(type) as IShop;
+                                if (shop != null)
+                                {
+                                    success += 1;
+                                    yield return shop;
+                                }
+                            }
+                        }
+                        if (success == 0)
+                        {
+                            logger.LogWarning("There were no shops found within the assembly at path \"{0}\".", file);
+                        }
+                    }
+                }
+            }
+        }
+    }
+}

Props/Services/Modules/ShopAssemblyLoadContext.cs

@@ -2,6 +2,7 @@ using System;
 using System.Reflection;
 using System.Runtime.Loader;
 using Microsoft.Extensions.DependencyModel;
+using Props.Shop.Framework;
 
 namespace Props.Services.Modules
 {
@@ -16,6 +17,7 @@ namespace Props.Services.Modules
 
         protected override Assembly Load(AssemblyName assemblyName)
         {
+            if (assemblyName.FullName.Equals(typeof(IShop).Assembly.FullName)) return null;
             string assemblyPath = resolver.ResolveAssemblyToPath(assemblyName);
             return assemblyPath != null ? LoadFromAssemblyPath(assemblyPath) : null;
         }