decouple API clients from mods API (#411)

18 files changed, 447 insertions, 213 deletions

diff --git a/src/SMAPI.Web/Controllers/ModsApiController.cs b/src/SMAPI.Web/Controllers/ModsApiController.cs
index a600662c..dcb4ec52 100644
--- a/src/SMAPI.Web/Controllers/ModsApiController.cs
+++ b/src/SMAPI.Web/Controllers/ModsApiController.cs
@@ -7,6 +7,9 @@ using Microsoft.AspNetCore.Mvc;
 using Microsoft.Extensions.Caching.Memory;
 using Microsoft.Extensions.Options;
 using StardewModdingAPI.Common.Models;
+using StardewModdingAPI.Web.Framework.Clients.Chucklefish;
+using StardewModdingAPI.Web.Framework.Clients.GitHub;
+using StardewModdingAPI.Web.Framework.Clients.Nexus;
 using StardewModdingAPI.Web.Framework.ConfigModels;
 using StardewModdingAPI.Web.Framework.ModRepositories;
 
@@ -39,39 +42,22 @@ namespace StardewModdingAPI.Web.Controllers
         /// <summary>Construct an instance.</summary>
         /// <param name="cache">The cache in which to store mod metadata.</param>
         /// <param name="configProvider">The config settings for mod update checks.</param>
-        public ModsApiController(IMemoryCache cache, IOptions<ModUpdateCheckConfig> configProvider)
+        /// <param name="chucklefish">The Chucklefish API client.</param>
+        /// <param name="github">The GitHub API client.</param>
+        /// <param name="nexus">The Nexus API client.</param>
+        public ModsApiController(IMemoryCache cache, IOptions<ModUpdateCheckConfig> configProvider, IChucklefishClient chucklefish, IGitHubClient github, INexusClient nexus)
         {
             ModUpdateCheckConfig config = configProvider.Value;
 
             this.Cache = cache;
             this.CacheMinutes = config.CacheMinutes;
             this.VersionRegex = config.SemanticVersionRegex;
-
-            string version = this.GetType().Assembly.GetName().Version.ToString(3);
             this.Repositories =
                 new IModRepository[]
                 {
-                    new ChucklefishRepository(
-                        vendorKey: config.ChucklefishKey,
-                        userAgent: string.Format(config.ChucklefishUserAgent, version),
-                        baseUrl: config.ChucklefishBaseUrl,
-                        modPageUrlFormat: config.ChucklefishModPageUrlFormat
-                    ),
-                    new GitHubRepository(
-                        vendorKey: config.GitHubKey,
-                        baseUrl: config.GitHubBaseUrl,
-                        releaseUrlFormat: config.GitHubReleaseUrlFormat,
-                        userAgent: string.Format(config.GitHubUserAgent, version),
-                        acceptHeader: config.GitHubAcceptHeader,
-                        username: config.GitHubUsername,
-                        password: config.GitHubPassword
-                    ),
-                    new NexusRepository(
-                        vendorKey: config.NexusKey,
-                        userAgent: config.NexusUserAgent,
-                        baseUrl: config.NexusBaseUrl,
-                        modUrlFormat: config.NexusModUrlFormat
-                    )
+                    new ChucklefishRepository(config.ChucklefishKey, chucklefish),
+                    new GitHubRepository(config.GitHubKey, github),
+                    new NexusRepository(config.NexusKey, nexus)
                 }
                 .ToDictionary(p => p.VendorKey, StringComparer.CurrentCultureIgnoreCase);
         }
diff --git a/src/SMAPI.Web/Framework/Clients/Chucklefish/ChucklefishClient.cs b/src/SMAPI.Web/Framework/Clients/Chucklefish/ChucklefishClient.cs
new file mode 100644
index 00000000..6772672c
--- /dev/null
+++ b/src/SMAPI.Web/Framework/Clients/Chucklefish/ChucklefishClient.cs
@@ -0,0 +1,83 @@
+using System;
+using System.Net;
+using System.Threading.Tasks;
+using HtmlAgilityPack;
+using Pathoschild.Http.Client;
+
+namespace StardewModdingAPI.Web.Framework.Clients.Chucklefish
+{
+    /// <summary>An HTTP client for fetching mod metadata from the Chucklefish mod site.</summary>
+    internal class ChucklefishClient : IChucklefishClient
+    {
+        /*********
+        ** Properties
+        *********/
+        /// <summary>The base URL for the Chucklefish mod site.</summary>
+        private readonly string BaseUrl;
+
+        /// <summary>The URL for a mod page excluding the base URL, where {0} is the mod ID.</summary>
+        private readonly string ModPageUrlFormat;
+
+        /// <summary>The underlying HTTP client.</summary>
+        private readonly IClient Client;
+
+
+        /*********
+        ** Public methods
+        *********/
+        /// <summary>Construct an instance.</summary>
+        /// <param name="userAgent">The user agent for the API client.</param>
+        /// <param name="baseUrl">The base URL for the Chucklefish mod site.</param>
+        /// <param name="modPageUrlFormat">The URL for a mod page excluding the <paramref name="baseUrl"/>, where {0} is the mod ID.</param>
+        public ChucklefishClient(string userAgent, string baseUrl, string modPageUrlFormat)
+        {
+            this.BaseUrl = baseUrl;
+            this.ModPageUrlFormat = modPageUrlFormat;
+            this.Client = new FluentClient(baseUrl).SetUserAgent(userAgent);
+        }
+
+        /// <summary>Get metadata about a mod.</summary>
+        /// <param name="id">The Chucklefish mod ID.</param>
+        /// <returns>Returns the mod info if found, else <c>null</c>.</returns>
+        public async Task<ChucklefishMod> GetModAsync(uint id)
+        {
+            // fetch HTML
+            string html;
+            try
+            {
+                html = await this.Client
+                    .GetAsync(string.Format(this.ModPageUrlFormat, id))
+                    .AsString();
+            }
+            catch (ApiException ex) when (ex.Status == HttpStatusCode.NotFound)
+            {
+                return null;
+            }
+
+            // parse HTML
+            var doc = new HtmlDocument();
+            doc.LoadHtml(html);
+
+            // extract mod info
+            string url = new UriBuilder(new Uri(this.BaseUrl)) { Path = string.Format(this.ModPageUrlFormat, id) }.Uri.ToString();
+            string name = doc.DocumentNode.SelectSingleNode("//meta[@name='twitter:title']").Attributes["content"].Value;
+            if (name.StartsWith("[SMAPI] "))
+                name = name.Substring("[SMAPI] ".Length);
+            string version = doc.DocumentNode.SelectSingleNode("//h1/span").InnerText;
+
+            // create model
+            return new ChucklefishMod
+            {
+                Name = name,
+                Version = version,
+                Url = url
+            };
+        }
+
+        /// <summary>Performs application-defined tasks associated with freeing, releasing, or resetting unmanaged resources.</summary>
+        public void Dispose()
+        {
+            this.Client?.Dispose();
+        }
+    }
+}
diff --git a/src/SMAPI.Web/Framework/Clients/Chucklefish/ChucklefishMod.cs b/src/SMAPI.Web/Framework/Clients/Chucklefish/ChucklefishMod.cs
new file mode 100644
index 00000000..fd0101d4
--- /dev/null
+++ b/src/SMAPI.Web/Framework/Clients/Chucklefish/ChucklefishMod.cs
@@ -0,0 +1,18 @@
+namespace StardewModdingAPI.Web.Framework.Clients.Chucklefish
+{
+    /// <summary>Mod metadata from the Chucklefish mod site.</summary>
+    internal class ChucklefishMod
+    {
+        /*********
+        ** Accessors
+        *********/
+        /// <summary>The mod name.</summary>
+        public string Name { get; set; }
+
+        /// <summary>The mod's semantic version number.</summary>
+        public string Version { get; set; }
+
+        /// <summary>The mod's web URL.</summary>
+        public string Url { get; set; }
+    }
+}
diff --git a/src/SMAPI.Web/Framework/Clients/Chucklefish/IChucklefishClient.cs b/src/SMAPI.Web/Framework/Clients/Chucklefish/IChucklefishClient.cs
new file mode 100644
index 00000000..1d8b256e
--- /dev/null
+++ b/src/SMAPI.Web/Framework/Clients/Chucklefish/IChucklefishClient.cs
@@ -0,0 +1,17 @@
+using System;
+using System.Threading.Tasks;
+
+namespace StardewModdingAPI.Web.Framework.Clients.Chucklefish
+{
+    /// <summary>An HTTP client for fetching mod metadata from the Chucklefish mod site.</summary>
+    internal interface IChucklefishClient : IDisposable
+    {
+        /*********
+        ** Methods
+        *********/
+        /// <summary>Get metadata about a mod.</summary>
+        /// <param name="id">The Chucklefish mod ID.</param>
+        /// <returns>Returns the mod info if found, else <c>null</c>.</returns>
+        Task<ChucklefishMod> GetModAsync(uint id);
+    }
+}
diff --git a/src/SMAPI.Web/Framework/Clients/GitHub/GitHubClient.cs b/src/SMAPI.Web/Framework/Clients/GitHub/GitHubClient.cs
new file mode 100644
index 00000000..0b205660
--- /dev/null
+++ b/src/SMAPI.Web/Framework/Clients/GitHub/GitHubClient.cs
@@ -0,0 +1,70 @@
+using System;
+using System.Net;
+using System.Threading.Tasks;
+using Pathoschild.Http.Client;
+
+namespace StardewModdingAPI.Web.Framework.Clients.GitHub
+{
+    /// <summary>An HTTP client for fetching metadata from GitHub.</summary>
+    internal class GitHubClient : IGitHubClient
+    {
+        /*********
+        ** Properties
+        *********/
+        /// <summary>The URL for a GitHub releases API query excluding the base URL, where {0} is the repository owner and name.</summary>
+        private readonly string ReleaseUrlFormat;
+
+        /// <summary>The underlying HTTP client.</summary>
+        private readonly IClient Client;
+
+
+        /*********
+        ** Public methods
+        *********/
+        /// <summary>Construct an instance.</summary>
+        /// <param name="baseUrl">The base URL for the GitHub API.</param>
+        /// <param name="releaseUrlFormat">The URL for a GitHub releases API query excluding the <paramref name="baseUrl"/>, where {0} is the repository owner and name.</param>
+        /// <param name="userAgent">The user agent for the API client.</param>
+        /// <param name="acceptHeader">The Accept header value expected by the GitHub API.</param>
+        /// <param name="username">The username with which to authenticate to the GitHub API.</param>
+        /// <param name="password">The password with which to authenticate to the GitHub API.</param>
+        public GitHubClient(string baseUrl, string releaseUrlFormat, string userAgent, string acceptHeader, string username, string password)
+        {
+            this.ReleaseUrlFormat = releaseUrlFormat;
+
+            this.Client = new FluentClient(baseUrl)
+                .SetUserAgent(userAgent)
+                .AddDefault(req => req.WithHeader("Accept", acceptHeader));
+            if (!string.IsNullOrWhiteSpace(username))
+                this.Client = this.Client.SetBasicAuthentication(username, password);
+        }
+
+        /// <summary>Get the latest release for a GitHub repository.</summary>
+        /// <param name="repo">The repository key (like <c>Pathoschild/SMAPI</c>).</param>
+        /// <returns>Returns the latest release if found, else <c>null</c>.</returns>
+        public async Task<GitRelease> GetLatestReleaseAsync(string repo)
+        {
+            // validate key format
+            if (!repo.Contains("/") || repo.IndexOf("/", StringComparison.InvariantCultureIgnoreCase) != repo.LastIndexOf("/", StringComparison.InvariantCultureIgnoreCase))
+                throw new ArgumentException($"The value '{repo}' isn't a valid GitHub repository key, must be a username and project name like 'Pathoschild/SMAPI'.", nameof(repo));
+
+            // fetch info
+            try
+            {
+                return await this.Client
+                    .GetAsync(string.Format(this.ReleaseUrlFormat, repo))
+                    .As<GitRelease>();
+            }
+            catch (ApiException ex) when (ex.Status == HttpStatusCode.NotFound)
+            {
+                return null;
+            }
+        }
+
+        /// <summary>Performs application-defined tasks associated with freeing, releasing, or resetting unmanaged resources.</summary>
+        public void Dispose()
+        {
+            this.Client?.Dispose();
+        }
+    }
+}
diff --git a/src/SMAPI.Web/Framework/Clients/GitHub/GitRelease.cs b/src/SMAPI.Web/Framework/Clients/GitHub/GitRelease.cs
new file mode 100644
index 00000000..0a47f3b4
--- /dev/null
+++ b/src/SMAPI.Web/Framework/Clients/GitHub/GitRelease.cs
@@ -0,0 +1,19 @@
+using Newtonsoft.Json;
+
+namespace StardewModdingAPI.Web.Framework.Clients.GitHub
+{
+    /// <summary>A GitHub project release.</summary>
+    internal class GitRelease
+    {
+        /*********
+        ** Accessors
+        *********/
+        /// <summary>The display name.</summary>
+        [JsonProperty("name")]
+        public string Name { get; set; }
+
+        /// <summary>The semantic version string.</summary>
+        [JsonProperty("tag_name")]
+        public string Tag { get; set; }
+    }
+}
diff --git a/src/SMAPI.Web/Framework/Clients/GitHub/IGitHubClient.cs b/src/SMAPI.Web/Framework/Clients/GitHub/IGitHubClient.cs
new file mode 100644
index 00000000..6e8eadff
--- /dev/null
+++ b/src/SMAPI.Web/Framework/Clients/GitHub/IGitHubClient.cs
@@ -0,0 +1,17 @@
+using System;
+using System.Threading.Tasks;
+
+namespace StardewModdingAPI.Web.Framework.Clients.GitHub
+{
+    /// <summary>An HTTP client for fetching metadata from GitHub.</summary>
+    internal interface IGitHubClient : IDisposable
+    {
+        /*********
+        ** Methods
+        *********/
+        /// <summary>Get the latest release for a GitHub repository.</summary>
+        /// <param name="repo">The repository key (like <c>Pathoschild/SMAPI</c>).</param>
+        /// <returns>Returns the latest release if found, else <c>null</c>.</returns>
+        Task<GitRelease> GetLatestReleaseAsync(string repo);
+    }
+}
diff --git a/src/SMAPI.Web/Framework/Clients/Nexus/INexusClient.cs b/src/SMAPI.Web/Framework/Clients/Nexus/INexusClient.cs
new file mode 100644
index 00000000..e56e7af4
--- /dev/null
+++ b/src/SMAPI.Web/Framework/Clients/Nexus/INexusClient.cs
@@ -0,0 +1,17 @@
+using System;
+using System.Threading.Tasks;
+
+namespace StardewModdingAPI.Web.Framework.Clients.Nexus
+{
+    /// <summary>An HTTP client for fetching mod metadata from Nexus Mods.</summary>
+    internal interface INexusClient : IDisposable
+    {
+        /*********
+        ** Methods
+        *********/
+        /// <summary>Get metadata about a mod.</summary>
+        /// <param name="id">The Nexus mod ID.</param>
+        /// <returns>Returns the mod info if found, else <c>null</c>.</returns>
+        Task<NexusMod> GetModAsync(uint id);
+    }
+}
diff --git a/src/SMAPI.Web/Framework/Clients/Nexus/NexusClient.cs b/src/SMAPI.Web/Framework/Clients/Nexus/NexusClient.cs
new file mode 100644
index 00000000..1a7011e2
--- /dev/null
+++ b/src/SMAPI.Web/Framework/Clients/Nexus/NexusClient.cs
@@ -0,0 +1,48 @@
+using System.Threading.Tasks;
+using Pathoschild.Http.Client;
+
+namespace StardewModdingAPI.Web.Framework.Clients.Nexus
+{
+    /// <summary>An HTTP client for fetching mod metadata from Nexus Mods.</summary>
+    internal class NexusClient : INexusClient
+    {
+        /*********
+        ** Properties
+        *********/
+        /// <summary>The URL for a Nexus Mods API query excluding the base URL, where {0} is the mod ID.</summary>
+        private readonly string ModUrlFormat;
+
+        /// <summary>The underlying HTTP client.</summary>
+        private readonly IClient Client;
+
+
+        /*********
+        ** Public methods
+        *********/
+        /// <summary>Construct an instance.</summary>
+        /// <param name="userAgent">The user agent for the Nexus Mods API client.</param>
+        /// <param name="baseUrl">The base URL for the Nexus Mods API.</param>
+        /// <param name="modUrlFormat">The URL for a Nexus Mods API query excluding the <paramref name="baseUrl"/>, where {0} is the mod ID.</param>
+        public NexusClient(string userAgent, string baseUrl, string modUrlFormat)
+        {
+            this.ModUrlFormat = modUrlFormat;
+            this.Client = new FluentClient(baseUrl).SetUserAgent(userAgent);
+        }
+
+        /// <summary>Get metadata about a mod.</summary>
+        /// <param name="id">The Nexus mod ID.</param>
+        /// <returns>Returns the mod info if found, else <c>null</c>.</returns>
+        public async Task<NexusMod> GetModAsync(uint id)
+        {
+            return await this.Client
+                .GetAsync(string.Format(this.ModUrlFormat, id))
+                .As<NexusMod>();
+        }
+
+        /// <summary>Performs application-defined tasks associated with freeing, releasing, or resetting unmanaged resources.</summary>
+        public void Dispose()
+        {
+            this.Client?.Dispose();
+        }
+    }
+}
diff --git a/src/SMAPI.Web/Framework/Clients/Nexus/NexusMod.cs b/src/SMAPI.Web/Framework/Clients/Nexus/NexusMod.cs
new file mode 100644
index 00000000..2b04104f
--- /dev/null
+++ b/src/SMAPI.Web/Framework/Clients/Nexus/NexusMod.cs
@@ -0,0 +1,21 @@
+using Newtonsoft.Json;
+
+namespace StardewModdingAPI.Web.Framework.Clients.Nexus
+{
+    /// <summary>Mod metadata from Nexus Mods.</summary>
+    internal class NexusMod
+    {
+        /*********
+        ** Accessors
+        *********/
+        /// <summary>The mod name.</summary>
+        public string Name { get; set; }
+
+        /// <summary>The mod's semantic version number.</summary>
+        public string Version { get; set; }
+
+        /// <summary>The mod's web URL.</summary>
+        [JsonProperty("mod_page_uri")]
+        public string Url { get; set; }
+    }
+}
diff --git a/src/SMAPI.Web/Framework/ConfigModels/ApiClientsConfig.cs b/src/SMAPI.Web/Framework/ConfigModels/ApiClientsConfig.cs
new file mode 100644
index 00000000..19794920
--- /dev/null
+++ b/src/SMAPI.Web/Framework/ConfigModels/ApiClientsConfig.cs
@@ -0,0 +1,56 @@
+namespace StardewModdingAPI.Web.Framework.ConfigModels
+{
+    /// <summary>The config settings for the API clients.</summary>
+    internal class ApiClientsConfig
+    {
+        /*********
+        ** Accessors
+        *********/
+        /****
+        ** Generic
+        ****/
+        /// <summary>The user agent for API clients, where {0} is the SMAPI version.</summary>
+        public string UserAgent { get; set; }
+
+
+        /****
+        ** Chucklefish
+        ****/
+        /// <summary>The base URL for the Chucklefish mod site.</summary>
+        public string ChucklefishBaseUrl { get; set; }
+
+        /// <summary>The URL for a mod page on the Chucklefish mod site excluding the <see cref="GitHubBaseUrl"/>, where {0} is the mod ID.</summary>
+        public string ChucklefishModPageUrlFormat { get; set; }
+
+
+        /****
+        ** GitHub
+        ****/
+        /// <summary>The base URL for the GitHub API.</summary>
+        public string GitHubBaseUrl { get; set; }
+
+        /// <summary>The URL for a GitHub API latest-release query excluding the <see cref="GitHubBaseUrl"/>, where {0} is the organisation and project name.</summary>
+        public string GitHubReleaseUrlFormat { get; set; }
+
+        /// <summary>The Accept header value expected by the GitHub API.</summary>
+        public string GitHubAcceptHeader { get; set; }
+
+        /// <summary>The username with which to authenticate to the GitHub API (if any).</summary>
+        public string GitHubUsername { get; set; }
+
+        /// <summary>The password with which to authenticate to the GitHub API (if any).</summary>
+        public string GitHubPassword { get; set; }
+
+        /****
+        ** Nexus Mods
+        ****/
+        /// <summary>The user agent for the Nexus Mods API client.</summary>
+        public string NexusUserAgent { get; set; }
+
+        /// <summary>The base URL for the Nexus Mods API.</summary>
+        public string NexusBaseUrl { get; set; }
+
+        /// <summary>The URL for a Nexus Mods API query excluding the <see cref="NexusBaseUrl"/>, where {0} is the mod ID.</summary>
+        public string NexusModUrlFormat { get; set; }
+    }
+}
diff --git a/src/SMAPI.Web/Framework/ConfigModels/ModUpdateCheckConfig.cs b/src/SMAPI.Web/Framework/ConfigModels/ModUpdateCheckConfig.cs
index 2fb5b97e..58c3a100 100644
--- a/src/SMAPI.Web/Framework/ConfigModels/ModUpdateCheckConfig.cs
+++ b/src/SMAPI.Web/Framework/ConfigModels/ModUpdateCheckConfig.cs
@@ -6,9 +6,6 @@ namespace StardewModdingAPI.Web.Framework.ConfigModels
         /*********
         ** Accessors
         *********/
-        /****
-        ** General
-        ****/
         /// <summary>The number of minutes update checks should be cached before refetching them.</summary>
         public int CacheMinutes { get; set; }
 
@@ -16,59 +13,13 @@ namespace StardewModdingAPI.Web.Framework.ConfigModels
         /// <remarks>Derived from SMAPI's SemanticVersion implementation.</remarks>
         public string SemanticVersionRegex { get; set; }
 
-        /****
-        ** Chucklefish mod site
-        ****/
         /// <summary>The repository key for the Chucklefish mod site.</summary>
         public string ChucklefishKey { get; set; }
 
-        /// <summary>The user agent for the Chucklefish API client, where {0} is the SMAPI version.</summary>
-        public string ChucklefishUserAgent { get; set; }
-
-        /// <summary>The base URL for the Chucklefish mod site.</summary>
-        public string ChucklefishBaseUrl { get; set; }
-
-        /// <summary>The URL for a mod page on the Chucklefish mod site excluding the <see cref="GitHubBaseUrl"/>, where {0} is the mod ID.</summary>
-        public string ChucklefishModPageUrlFormat { get; set; }
-
-
-        /****
-        ** GitHub
-        ****/
         /// <summary>The repository key for Nexus Mods.</summary>
         public string GitHubKey { get; set; }
 
-        /// <summary>The user agent for the GitHub API client, where {0} is the SMAPI version.</summary>
-        public string GitHubUserAgent { get; set; }
-
-        /// <summary>The base URL for the GitHub API.</summary>
-        public string GitHubBaseUrl { get; set; }
-
-        /// <summary>The URL for a GitHub API latest-release query excluding the <see cref="GitHubBaseUrl"/>, where {0} is the organisation and project name.</summary>
-        public string GitHubReleaseUrlFormat { get; set; }
-
-        /// <summary>The Accept header value expected by the GitHub API.</summary>
-        public string GitHubAcceptHeader { get; set; }
-
-        /// <summary>The username with which to authenticate to the GitHub API (if any).</summary>
-        public string GitHubUsername { get; set; }
-
-        /// <summary>The password with which to authenticate to the GitHub API (if any).</summary>
-        public string GitHubPassword { get; set; }
-
-        /****
-        ** Nexus Mods
-        ****/
         /// <summary>The repository key for Nexus Mods.</summary>
         public string NexusKey { get; set; }
-
-        /// <summary>The user agent for the Nexus Mods API client.</summary>
-        public string NexusUserAgent { get; set; }
-
-        /// <summary>The base URL for the Nexus Mods API.</summary>
-        public string NexusBaseUrl { get; set; }
-
-        /// <summary>The URL for a Nexus Mods API query excluding the <see cref="NexusBaseUrl"/>, where {0} is the mod ID.</summary>
-        public string NexusModUrlFormat { get; set; }
     }
 }
diff --git a/src/SMAPI.Web/Framework/ModRepositories/ChucklefishRepository.cs b/src/SMAPI.Web/Framework/ModRepositories/ChucklefishRepository.cs
index 06ec58ed..266055a6 100644
--- a/src/SMAPI.Web/Framework/ModRepositories/ChucklefishRepository.cs
+++ b/src/SMAPI.Web/Framework/ModRepositories/ChucklefishRepository.cs
@@ -1,9 +1,7 @@
 using System;
-using System.Net;
 using System.Threading.Tasks;
-using HtmlAgilityPack;
-using Pathoschild.Http.Client;
 using StardewModdingAPI.Common.Models;
+using StardewModdingAPI.Web.Framework.Clients.Chucklefish;
 
 namespace StardewModdingAPI.Web.Framework.ModRepositories
 {
@@ -13,14 +11,8 @@ namespace StardewModdingAPI.Web.Framework.ModRepositories
         /*********
         ** Properties
         *********/
-        /// <summary>The base URL for the Chucklefish mod site.</summary>
-        private readonly string BaseUrl;
-
-        /// <summary>The URL for a mod page excluding the base URL, where {0} is the mod ID.</summary>
-        private readonly string ModPageUrlFormat;
-
         /// <summary>The underlying HTTP client.</summary>
-        private readonly IClient Client;
+        private readonly IChucklefishClient Client;
 
 
         /*********
@@ -28,15 +20,11 @@ namespace StardewModdingAPI.Web.Framework.ModRepositories
         *********/
         /// <summary>Construct an instance.</summary>
         /// <param name="vendorKey">The unique key for this vendor.</param>
-        /// <param name="userAgent">The user agent for the API client.</param>
-        /// <param name="baseUrl">The base URL for the Chucklefish mod site.</param>
-        /// <param name="modPageUrlFormat">The URL for a mod page excluding the <paramref name="baseUrl"/>, where {0} is the mod ID.</param>
-        public ChucklefishRepository(string vendorKey, string userAgent, string baseUrl, string modPageUrlFormat)
+        /// <param name="client">The underlying HTTP client.</param>
+        public ChucklefishRepository(string vendorKey, IChucklefishClient client)
             : base(vendorKey)
         {
-            this.BaseUrl = baseUrl;
-            this.ModPageUrlFormat = modPageUrlFormat;
-            this.Client = new FluentClient(baseUrl).SetUserAgent(userAgent);
+            this.Client = client;
         }
 
         /// <summary>Get metadata about a mod in the repository.</summary>
@@ -44,38 +32,18 @@ namespace StardewModdingAPI.Web.Framework.ModRepositories
         public override async Task<ModInfoModel> GetModInfoAsync(string id)
         {
             // validate ID format
-            if (!uint.TryParse(id, out uint _))
+            if (!uint.TryParse(id, out uint realID))
                 return new ModInfoModel($"The value '{id}' isn't a valid Chucklefish mod ID, must be an integer ID.");
 
             // fetch info
             try
             {
-                // fetch HTML
-                string html;
-                try
-                {
-                    html = await this.Client
-                        .GetAsync(string.Format(this.ModPageUrlFormat, id))
-                        .AsString();
-                }
-                catch (ApiException ex) when (ex.Status == HttpStatusCode.NotFound)
-                {
+                var mod = await this.Client.GetModAsync(realID);
+                if (mod == null)
                     return new ModInfoModel("Found no mod with this ID.");
-                }
-
-                // parse HTML
-                var doc = new HtmlDocument();
-                doc.LoadHtml(html);
-
-                // extract mod info
-                string url = new UriBuilder(new Uri(this.BaseUrl)) { Path = string.Format(this.ModPageUrlFormat, id) }.Uri.ToString();
-                string name = doc.DocumentNode.SelectSingleNode("//meta[@name='twitter:title']").Attributes["content"].Value;
-                if (name.StartsWith("[SMAPI] "))
-                    name = name.Substring("[SMAPI] ".Length);
-                string version = doc.DocumentNode.SelectSingleNode("//h1/span").InnerText;
 
                 // create model
-                return new ModInfoModel(name, this.NormaliseVersion(version), url);
+                return new ModInfoModel(mod.Name, this.NormaliseVersion(mod.Version), mod.Url);
             }
             catch (Exception ex)
             {
diff --git a/src/SMAPI.Web/Framework/ModRepositories/GitHubRepository.cs b/src/SMAPI.Web/Framework/ModRepositories/GitHubRepository.cs
index 9d43adf0..7bad6127 100644
--- a/src/SMAPI.Web/Framework/ModRepositories/GitHubRepository.cs
+++ b/src/SMAPI.Web/Framework/ModRepositories/GitHubRepository.cs
@@ -1,9 +1,7 @@
 using System;
-using System.Net;
 using System.Threading.Tasks;
-using Newtonsoft.Json;
-using Pathoschild.Http.Client;
 using StardewModdingAPI.Common.Models;
+using StardewModdingAPI.Web.Framework.Clients.GitHub;
 
 namespace StardewModdingAPI.Web.Framework.ModRepositories
 {
@@ -13,11 +11,8 @@ namespace StardewModdingAPI.Web.Framework.ModRepositories
         /*********
         ** Properties
         *********/
-        /// <summary>The URL for a Nexus Mods API query excluding the base URL, where {0} is the mod ID.</summary>
-        private readonly string ReleaseUrlFormat;
-
-        /// <summary>The underlying HTTP client.</summary>
-        private readonly IClient Client;
+        /// <summary>The underlying GitHub API client.</summary>
+        private readonly IGitHubClient Client;
 
 
         /*********
@@ -25,22 +20,11 @@ namespace StardewModdingAPI.Web.Framework.ModRepositories
         *********/
         /// <summary>Construct an instance.</summary>
         /// <param name="vendorKey">The unique key for this vendor.</param>
-        /// <param name="baseUrl">The base URL for the Nexus Mods API.</param>
-        /// <param name="releaseUrlFormat">The URL for a Nexus Mods API query excluding the <paramref name="baseUrl"/>, where {0} is the mod ID.</param>
-        /// <param name="userAgent">The user agent for the API client.</param>
-        /// <param name="acceptHeader">The Accept header value expected by the GitHub API.</param>
-        /// <param name="username">The username with which to authenticate to the GitHub API.</param>
-        /// <param name="password">The password with which to authenticate to the GitHub API.</param>
-        public GitHubRepository(string vendorKey, string baseUrl, string releaseUrlFormat, string userAgent, string acceptHeader, string username, string password)
+        /// <param name="client">The underlying GitHub API client.</param>
+        public GitHubRepository(string vendorKey, IGitHubClient client)
             : base(vendorKey)
         {
-            this.ReleaseUrlFormat = releaseUrlFormat;
-
-            this.Client = new FluentClient(baseUrl)
-                .SetUserAgent(userAgent)
-                .AddDefault(req => req.WithHeader("Accept", acceptHeader));
-            if (!string.IsNullOrWhiteSpace(username))
-                this.Client = this.Client.SetBasicAuthentication(username, password);
+            this.Client = client;
         }
 
         /// <summary>Get metadata about a mod in the repository.</summary>
@@ -54,14 +38,10 @@ namespace StardewModdingAPI.Web.Framework.ModRepositories
             // fetch info
             try
             {
-                GitRelease release = await this.Client
-                    .GetAsync(string.Format(this.ReleaseUrlFormat, id))
-                    .As<GitRelease>();
-                return new ModInfoModel(id, this.NormaliseVersion(release.Tag), $"https://github.com/{id}/releases");
-            }
-            catch (ApiException ex) when (ex.Status == HttpStatusCode.NotFound)
-            {
-                return new ModInfoModel("Found no mod with this ID.");
+                GitRelease release = await this.Client.GetLatestReleaseAsync(id);
+                return release != null
+                    ? new ModInfoModel(id, this.NormaliseVersion(release.Tag), $"https://github.com/{id}/releases")
+                    : new ModInfoModel("Found no mod with this ID.");
             }
             catch (Exception ex)
             {
@@ -74,24 +54,5 @@ namespace StardewModdingAPI.Web.Framework.ModRepositories
         {
             this.Client.Dispose();
         }
-
-
-        /*********
-        ** Private models
-        *********/
-        /// <summary>Metadata about a GitHub release tag.</summary>
-        private class GitRelease
-        {
-            /*********
-            ** Accessors
-            *********/
-            /// <summary>The display name.</summary>
-            [JsonProperty("name")]
-            public string Name { get; set; }
-
-            /// <summary>The semantic version string.</summary>
-            [JsonProperty("tag_name")]
-            public string Tag { get; set; }
-        }
     }
 }
diff --git a/src/SMAPI.Web/Framework/ModRepositories/NexusRepository.cs b/src/SMAPI.Web/Framework/ModRepositories/NexusRepository.cs
index 8a4bb0d8..cfa757ab 100644
--- a/src/SMAPI.Web/Framework/ModRepositories/NexusRepository.cs
+++ b/src/SMAPI.Web/Framework/ModRepositories/NexusRepository.cs
@@ -1,8 +1,7 @@
 using System;
 using System.Threading.Tasks;
-using Newtonsoft.Json;
-using Pathoschild.Http.Client;
 using StardewModdingAPI.Common.Models;
+using StardewModdingAPI.Web.Framework.Clients.Nexus;
 
 namespace StardewModdingAPI.Web.Framework.ModRepositories
 {
@@ -12,11 +11,8 @@ namespace StardewModdingAPI.Web.Framework.ModRepositories
         /*********
         ** Properties
         *********/
-        /// <summary>The URL for a Nexus Mods API query excluding the base URL, where {0} is the mod ID.</summary>
-        private readonly string ModUrlFormat;
-
-        /// <summary>The underlying HTTP client.</summary>
-        private readonly IClient Client;
+        /// <summary>The underlying Nexus Mods API client.</summary>
+        private readonly INexusClient Client;
 
 
         /*********
@@ -24,14 +20,11 @@ namespace StardewModdingAPI.Web.Framework.ModRepositories
         *********/
         /// <summary>Construct an instance.</summary>
         /// <param name="vendorKey">The unique key for this vendor.</param>
-        /// <param name="userAgent">The user agent for the Nexus Mods API client.</param>
-        /// <param name="baseUrl">The base URL for the Nexus Mods API.</param>
-        /// <param name="modUrlFormat">The URL for a Nexus Mods API query excluding the <paramref name="baseUrl"/>, where {0} is the mod ID.</param>
-        public NexusRepository(string vendorKey, string userAgent, string baseUrl, string modUrlFormat)
+        /// <param name="client">The underlying Nexus Mods API client.</param>
+        public NexusRepository(string vendorKey, INexusClient client)
             : base(vendorKey)
         {
-            this.ModUrlFormat = modUrlFormat;
-            this.Client = new FluentClient(baseUrl).SetUserAgent(userAgent);
+            this.Client = client;
         }
 
         /// <summary>Get metadata about a mod in the repository.</summary>
@@ -39,18 +32,15 @@ namespace StardewModdingAPI.Web.Framework.ModRepositories
         public override async Task<ModInfoModel> GetModInfoAsync(string id)
         {
             // validate ID format
-            if (!uint.TryParse(id, out uint _))
+            if (!uint.TryParse(id, out uint nexusID))
                 return new ModInfoModel($"The value '{id}' isn't a valid Nexus mod ID, must be an integer ID.");
 
             // fetch info
             try
             {
-                NexusResponseModel response = await this.Client
-                    .GetAsync(string.Format(this.ModUrlFormat, id))
-                    .As<NexusResponseModel>();
-
-                return response != null
-                    ? new ModInfoModel(response.Name, this.NormaliseVersion(response.Version), response.Url)
+                NexusMod mod = await this.Client.GetModAsync(nexusID);
+                return mod != null
+                    ? new ModInfoModel(mod.Name, this.NormaliseVersion(mod.Version), mod.Url)
                     : new ModInfoModel("Found no mod with this ID.");
             }
             catch (Exception ex)
@@ -64,26 +54,5 @@ namespace StardewModdingAPI.Web.Framework.ModRepositories
         {
             this.Client.Dispose();
         }
-
-
-        /*********
-        ** Private models
-        *********/
-        /// <summary>A mod metadata response from Nexus Mods.</summary>
-        private class NexusResponseModel
-        {
-            /*********
-            ** Accessors
-            *********/
-            /// <summary>The mod name.</summary>
-            public string Name { get; set; }
-
-            /// <summary>The mod's semantic version number.</summary>
-            public string Version { get; set; }
-
-            /// <summary>The mod's web URL.</summary>
-            [JsonProperty("mod_page_uri")]
-            public string Url { get; set; }
-        }
     }
 }
diff --git a/src/SMAPI.Web/Startup.cs b/src/SMAPI.Web/Startup.cs
index 2f2b0d11..7938520a 100644
--- a/src/SMAPI.Web/Startup.cs
+++ b/src/SMAPI.Web/Startup.cs
@@ -7,6 +7,9 @@ using Microsoft.Extensions.DependencyInjection;
 using Microsoft.Extensions.Logging;
 using Newtonsoft.Json;
 using StardewModdingAPI.Web.Framework;
+using StardewModdingAPI.Web.Framework.Clients.Chucklefish;
+using StardewModdingAPI.Web.Framework.Clients.GitHub;
+using StardewModdingAPI.Web.Framework.Clients.Nexus;
 using StardewModdingAPI.Web.Framework.ConfigModels;
 using StardewModdingAPI.Web.Framework.RewriteRules;
 
@@ -41,6 +44,7 @@ namespace StardewModdingAPI.Web
         /// <param name="services">The service injection container.</param>
         public void ConfigureServices(IServiceCollection services)
         {
+            // init configuration
             services
                 .Configure<ModUpdateCheckConfig>(this.Configuration.GetSection("ModUpdateCheck"))
                 .Configure<LogParserConfig>(this.Configuration.GetSection("LogParser"))
@@ -53,6 +57,32 @@ namespace StardewModdingAPI.Web
                     options.SerializerSettings.Formatting = Formatting.Indented;
                     options.SerializerSettings.NullValueHandling = NullValueHandling.Ignore;
                 });
+
+            // init API clients
+            {
+                ApiClientsConfig api = this.Configuration.GetSection("ApiClients").Get<ApiClientsConfig>();
+                string version = this.GetType().Assembly.GetName().Version.ToString(3);
+                string userAgent = string.Format(api.UserAgent, version);
+
+                services.AddSingleton<IChucklefishClient>(new ChucklefishClient(
+                    userAgent: userAgent,
+                    baseUrl: api.ChucklefishBaseUrl,
+                    modPageUrlFormat: api.ChucklefishModPageUrlFormat
+                ));
+                services.AddSingleton<IGitHubClient>(new GitHubClient(
+                    baseUrl: api.GitHubBaseUrl,
+                    releaseUrlFormat: api.GitHubReleaseUrlFormat,
+                    userAgent: userAgent,
+                    acceptHeader: api.GitHubAcceptHeader,
+                    username: api.GitHubUsername,
+                    password: api.GitHubPassword
+                ));
+                services.AddSingleton<INexusClient>(new NexusClient(
+                    userAgent: api.NexusUserAgent,
+                    baseUrl: api.NexusBaseUrl,
+                    modUrlFormat: api.NexusModUrlFormat
+                ));
+            }
         }
 
         /// <summary>The method called by the runtime to configure the HTTP request pipeline.</summary>
diff --git a/src/SMAPI.Web/appsettings.Development.json b/src/SMAPI.Web/appsettings.Development.json
index 87c35ca9..4602d1ed 100644
--- a/src/SMAPI.Web/appsettings.Development.json
+++ b/src/SMAPI.Web/appsettings.Development.json
@@ -16,7 +16,7 @@
       "Microsoft": "Information"
     }
   },
-  "ModUpdateCheck": {
+  "ApiClients": {
     "GitHubUsername": null,
     "GitHubPassword": null
   },
diff --git a/src/SMAPI.Web/appsettings.json b/src/SMAPI.Web/appsettings.json
index eb6ecc9b..4f70b41b 100644
--- a/src/SMAPI.Web/appsettings.json
+++ b/src/SMAPI.Web/appsettings.json
@@ -13,28 +13,31 @@
       "Default": "Warning"
     }
   },
-  "ModUpdateCheck": {
-    "CacheMinutes": 60,
-    "SemanticVersionRegex": "^(?>(?<major>0|[1-9]\\d*))\\.(?>(?<minor>0|[1-9]\\d*))(?>(?:\\.(?<patch>0|[1-9]\\d*))?)(?:-(?<prerelease>(?>[a-z0-9]+[\\-\\.]?)+))?$",
+  "ApiClients": {
+    "UserAgent": "SMAPI/{0} (+https://github.com/Pathoschild/SMAPI)",
 
-    "ChucklefishKey": "Chucklefish",
-    "ChucklefishUserAgent": "SMAPI/{0} (+https://github.com/Pathoschild/SMAPI)",
     "ChucklefishBaseUrl": "https://community.playstarbound.com",
     "ChucklefishModPageUrlFormat": "resources/{0}",
 
-    "GitHubKey": "GitHub",
-    "GitHubUserAgent": "SMAPI/{0} (+https://github.com/Pathoschild/SMAPI)",
     "GitHubBaseUrl": "https://api.github.com",
     "GitHubReleaseUrlFormat": "repos/{0}/releases/latest",
     "GitHubAcceptHeader": "application/vnd.github.v3+json",
     "GitHubUsername": null, // see top note
     "GitHubPassword": null, // see top note
 
-    "NexusKey": "Nexus",
     "NexusUserAgent": "Nexus Client v0.63.15",
     "NexusBaseUrl": "http://www.nexusmods.com/stardewvalley",
     "NexusModUrlFormat": "mods/{0}"
   },
+
+  "ModUpdateCheck": {
+    "CacheMinutes": 60,
+    "SemanticVersionRegex": "^(?>(?<major>0|[1-9]\\d*))\\.(?>(?<minor>0|[1-9]\\d*))(?>(?:\\.(?<patch>0|[1-9]\\d*))?)(?:-(?<prerelease>(?>[a-z0-9]+[\\-\\.]?)+))?$",
+
+    "ChucklefishKey": "Chucklefish",
+    "GitHubKey": "GitHub",
+    "NexusKey": "Nexus"
+  },
   "LogParser": {
     "SectionUrl": null, // see top note
     "PastebinBaseUrl": "https://pastebin.com/",