[Protocol] Mirror nuget.org's undocumented protocols (#249)

NuGet.org uses RDF to generate its V3 API. This adds properties that aren't part of the official API, however, certain clients depend on these undocumented properties.

src/BaGet.Core.Server/Controllers/Registration/RegistrationIndexController.cs

@@ -51,6 +51,7 @@ public async Task<IActionResult> Get(string id, CancellationToken cancellationTo
             // "Un-paged" example: https://api.nuget.org/v3/registration3/newtonsoft.json/index.json
             // Paged example: https://api.nuget.org/v3/registration3/fake/index.json
             return Json(new RegistrationIndex(
+                type: RegistrationIndex.DefaultType,
                 count: packages.Count,
                 totalDownloads: packages.Sum(p => p.Downloads),
                 pages: new[]
@@ -68,7 +69,7 @@ private RegistrationIndexPageItem ToRegistrationIndexPageItem(Package package) =
             new RegistrationIndexPageItem(
                 leafUrl: Url.PackageRegistration(package.Id, package.Version),
                 packageMetadata: new PackageMetadata(
-                    catalogUri: $"https://api.nuget.org/v3/catalog0/data/2015.02.01.06.24.15/{package.Id}.{package.Version}.json",
+                    catalogUri: Url.PackageRegistration(package.Id, package.Version),
                     packageId: package.Id,
                     version: package.Version,
                     authors: string.Join(", ", package.Authors),
@@ -115,4 +116,4 @@ private IReadOnlyList<DependencyGroupItem> ToDependencyGroups(Package package)
             return groups;
         }
     }
-}
+}

src/BaGet.Core.Server/Controllers/Registration/RegistrationLeafController.cs

@@ -44,6 +44,7 @@ public async Task<IActionResult> Get(string id, string version, CancellationToke
             }
 
             var result = new RegistrationLeaf(
+                type: RegistrationLeaf.DefaultType,
                 registrationUri: Url.PackageRegistration(id, nugetVersion),
                 listed: package.Listed,
                 downloads: package.Downloads,
@@ -54,4 +55,4 @@ public async Task<IActionResult> Get(string id, string version, CancellationToke
             return Json(result);
         }
     }
-}
+}

src/BaGet.Core.Server/Controllers/SearchController.cs

@@ -43,14 +43,18 @@ public async Task<ActionResult<SearchResponse>> Get(
 
             return new SearchResponse(
                 totalHits: results.Count,
-                data: results.Select(ToSearchResult).ToList());
+                data: results.Select(ToSearchResult).ToList(),
+                context: SearchContext.Default(Url.RegistrationsBase()));
         }
 
         public async Task<ActionResult<AutocompleteResult>> Autocomplete([FromQuery(Name = "q")] string query = null)
         {
             var results = await _searchService.AutocompleteAsync(query);
 
-            return new AutocompleteResult(results.Count, results);
+            return new AutocompleteResult(
+                results.Count,
+                results,
+                AutocompleteContext.Default);
         }
 
         public async Task<ActionResult<DependentResult>> Dependents([FromQuery(Name = "packageId")] string packageId)

src/BaGet.Protocol/HttpClientExtensions.cs

@@ -0,0 +1,54 @@
+using System.IO;
+using System.Net;
+using System.Net.Http;
+using System.Threading.Tasks;
+using Newtonsoft.Json;
+
+namespace BaGet.Protocol
+{
+    internal static class HttpClientExtensions
+    {
+        private static readonly JsonSerializer Serializer = JsonSerializer.Create(Settings);
+
+        private static readonly JsonSerializerSettings Settings = new JsonSerializerSettings
+        {
+            DateTimeZoneHandling = DateTimeZoneHandling.Utc,
+            DateParseHandling = DateParseHandling.DateTimeOffset,
+            NullValueHandling = NullValueHandling.Ignore,
+        };
+
+        public static async Task<ResponseAndResult<T>> DeserializeUrlAsync<T>(
+            this HttpClient httpClient,
+            string documentUrl)
+        {
+            using (var response = await httpClient.GetAsync(
+                documentUrl,
+                HttpCompletionOption.ResponseHeadersRead))
+            {
+                if (response.StatusCode != HttpStatusCode.OK)
+                {
+                    return new ResponseAndResult<T>(
+                        HttpMethod.Get,
+                        documentUrl,
+                        response.StatusCode,
+                        response.ReasonPhrase,
+                        hasResult: false,
+                        result: default);
+                }
+
+                using (var stream = await response.Content.ReadAsStreamAsync())
+                using (var textReader = new StreamReader(stream))
+                using (var jsonReader = new JsonTextReader(textReader))
+                {
+                    return new ResponseAndResult<T>(
+                        HttpMethod.Get,
+                        documentUrl,
+                        response.StatusCode,
+                        response.ReasonPhrase,
+                        hasResult: true,
+                        result: Serializer.Deserialize<T>(jsonReader));
+                }
+            }
+        }
+    }
+}

src/BaGet.Protocol/PackageContent/PackageContentClient.cs

@@ -1,4 +1,4 @@
-using System;
+using System;
 using System.IO;
 using System.Net;
 using System.Net.Http;
@@ -22,15 +22,13 @@ public PackageContentClient(HttpClient httpClient)
         /// <returns>The package's versions, or null if the package does not exist</returns>
         public async Task<PackageVersions> GetPackageVersionsOrNullAsync(string url)
         {
-            var response = await _httpClient.GetAsync(url);
+            var response = await _httpClient.DeserializeUrlAsync<PackageVersions>(url);
             if (response.StatusCode == HttpStatusCode.NotFound)
             {
                 return null;
             }
 
-            response.EnsureSuccessStatusCode();
-
-            return await response.Content.ReadAsAsync<PackageVersions>();
+            return response.GetResultOrThrow();
         }
 
         public async Task<Stream> GetPackageContentStreamAsync(string url)

src/BaGet.Protocol/ProtocolException.cs

@@ -0,0 +1,27 @@
+using System;
+using System.Net;
+using System.Net.Http;
+
+namespace BaGet.Protocol
+{
+    public class ProtocolException : Exception
+    {
+        public ProtocolException(
+            string message,
+            HttpMethod method,
+            string requestUri,
+            HttpStatusCode statusCode,
+            string reasonPhrase) : base(message)
+        {
+            Method = method ?? throw new ArgumentNullException(nameof(method));
+            RequestUri = requestUri ?? throw new ArgumentNullException(nameof(requestUri));
+            StatusCode = statusCode;
+            ReasonPhrase = reasonPhrase ?? throw new ArgumentNullException(nameof(reasonPhrase));
+        }
+
+        public HttpMethod Method { get; }
+        public string RequestUri { get; }
+        public HttpStatusCode StatusCode { get; }
+        public string ReasonPhrase { get; }
+    }
+}

src/BaGet.Protocol/Registration/RegistrationClient.cs

@@ -1,4 +1,4 @@
-using System;
+using System;
 using System.Net;
 using System.Net.Http;
 using System.Threading.Tasks;
@@ -16,33 +16,27 @@ public RegistrationClient(HttpClient httpClient)
 
         public async Task<RegistrationIndex> GetRegistrationIndexOrNullAsync(string indexUrl)
         {
-            var response = await _httpClient.GetAsync(indexUrl);
+            var response = await _httpClient.DeserializeUrlAsync<RegistrationIndex>(indexUrl);
             if (response.StatusCode == HttpStatusCode.NotFound)
             {
                 return null;
             }
 
-            response.EnsureSuccessStatusCode();
-
-            return await response.Content.ReadAsAsync<RegistrationIndex>();
+            return response.GetResultOrThrow();
         }
 
         public async Task<RegistrationIndexPage> GetRegistrationIndexPageAsync(string pageUrl)
         {
-            var response = await _httpClient.GetAsync(pageUrl);
-
-            response.EnsureSuccessStatusCode();
+            var response = await _httpClient.DeserializeUrlAsync<RegistrationIndexPage>(pageUrl);
 
-            return await response.Content.ReadAsAsync<RegistrationIndexPage>();
+            return response.GetResultOrThrow();
         }
 
         public async Task<RegistrationLeaf> GetRegistrationLeafAsync(string leafUrl)
         {
-            var response = await _httpClient.GetAsync(leafUrl);
-
-            response.EnsureSuccessStatusCode();
+            var response = await _httpClient.DeserializeUrlAsync<RegistrationLeaf>(leafUrl);
 
-            return await response.Content.ReadAsAsync<RegistrationLeaf>();
+            return response.GetResultOrThrow();
         }
     }
 }

src/BaGet.Protocol/Registration/RegistrationIndex.cs

@@ -1,4 +1,4 @@
-using System;
+using System;
 using System.Collections.Generic;
 using Newtonsoft.Json;
 
@@ -9,12 +9,27 @@ namespace BaGet.Protocol
     /// </summary>
     public class RegistrationIndex
     {
-        public RegistrationIndex(int count, long totalDownloads, IReadOnlyList<RegistrationIndexPage> pages)
+        public static readonly IReadOnlyList<string> DefaultType = new List<string>
+        {
+            "catalog:CatalogRoot",
+            "PackageRegistration",
+            "catalog:Permalink"
+        };
+
+        public RegistrationIndex(
+            int count,
+            long totalDownloads,
+            IReadOnlyList<RegistrationIndexPage> pages,
+            IReadOnlyList<string> type = null)
         {
             Count = count;
             Pages = pages ?? throw new ArgumentNullException(nameof(pages));
+            Type = type;
         }
 
+        [JsonProperty(PropertyName = "@type")]
+        public IReadOnlyList<string> Type { get; }
+
         /// <summary>
         /// The number of registration pages. See <see cref="Pages"/>. 
         /// </summary>

src/BaGet.Protocol/Registration/RegistrationLeaf.cs

@@ -1,4 +1,5 @@
-using System;
+using System;
+using System.Collections.Generic;
 using Newtonsoft.Json;
 
 namespace BaGet.Protocol
@@ -9,25 +10,36 @@ namespace BaGet.Protocol
     /// </summary>
     public class RegistrationLeaf
     {
+        public static readonly IReadOnlyList<string> DefaultType = new List<string>
+        {
+            "Package",
+            "http://schema.nuget.org/catalog#Permalink"
+        };
+
         public RegistrationLeaf(
             string registrationUri,
             bool listed,
             long downloads,
             string packageContentUrl,
             DateTimeOffset published,
-            string registrationIndexUrl)
+            string registrationIndexUrl,
+            IReadOnlyList<string> type = null)
         {
             RegistrationUri = registrationUri ?? throw new ArgumentNullException(nameof(registrationIndexUrl));
             Listed = listed;
             Published = published;
             Downloads = downloads;
             PackageContentUrl = packageContentUrl ?? throw new ArgumentNullException(nameof(packageContentUrl));
             RegistrationIndexUrl = registrationIndexUrl ?? throw new ArgumentNullException(nameof(registrationIndexUrl));
+            Type = type;
         }
 
         [JsonProperty(PropertyName = "@id")]
         public string RegistrationUri { get; }
 
+        [JsonProperty(PropertyName = "@type")]
+        public IReadOnlyList<string> Type { get; }
+
         public bool Listed { get; }
 
         public long Downloads { get; }

src/BaGet.Protocol/ResponseAndResult.cs

@@ -0,0 +1,49 @@
+using System;
+using System.Net;
+using System.Net.Http;
+
+namespace BaGet.Protocol
+{
+    internal class ResponseAndResult<T>
+    {
+        public ResponseAndResult(
+            HttpMethod method,
+            string requestUri,
+            HttpStatusCode statusCode,
+            string reasonPhrase,
+            bool hasResult,
+            T result)
+        {
+            Method = method ?? throw new ArgumentNullException(nameof(method));
+            RequestUri = requestUri ?? throw new ArgumentNullException(nameof(requestUri));
+            StatusCode = statusCode;
+            ReasonPhrase = reasonPhrase ?? throw new ArgumentNullException(nameof(reasonPhrase));
+            HasResult = hasResult;
+            Result = result;
+        }
+
+        public HttpMethod Method { get; }
+        public string RequestUri { get; }
+        public HttpStatusCode StatusCode { get; }
+        public string ReasonPhrase { get; }
+        public bool HasResult { get; }
+        public T Result { get; }
+
+        public T GetResultOrThrow()
+        {
+            if (!HasResult)
+            {
+                throw new ProtocolException(
+                    $"The HTTP request failed.{Environment.NewLine}" +
+                    $"Request: {Method} {RequestUri}{Environment.NewLine}" +
+                    $"Response: {(int)StatusCode} {ReasonPhrase}",
+                    Method,
+                    RequestUri,
+                    StatusCode,
+                    ReasonPhrase);
+            }
+
+            return Result;
+        }
+    }
+}

src/BaGet.Protocol/Search/AutocompleteContext.cs

@@ -0,0 +1,15 @@
+using Newtonsoft.Json;
+
+namespace BaGet.Protocol
+{
+    public class AutocompleteContext
+    {
+        public static readonly AutocompleteContext Default = new AutocompleteContext
+        {
+            Vocab = "http://schema.nuget.org/schema#"
+        };
+
+        [JsonProperty("@vocab")]
+        public string Vocab { get; set; }
+    }
+}