Merge pull request #40 from thefringeninja/list-streams

Support List Streams API

Author: thefringeninja

src/SqlStreamStore.HAL/AllStream/AllStreamResource.cs

@@ -57,6 +57,7 @@ public async Task<Response> Get(
                             .FromOperation(operation)
                             .Index()
                             .Find()
+                            .Browse()
                             .AllStreamNavigation(page, operation))
                     .AddEmbeddedCollection(
                         Constants.Relations.Message,

src/SqlStreamStore.HAL/AllStreamMessage/AllStreamMessageResource.cs

@@ -29,6 +29,7 @@ public async Task<Response> Get(
                 .FromOperation(operation)
                 .Index()
                 .Find()
+                .Browse()
                 .Add(
                     Constants.Relations.Message,
                     $"stream/{message.Position}",
@@ -62,7 +63,7 @@ public async Task<Response> Get(
                     message.Type,
                     payload,
                     metadata = message.JsonMetadata
-                }).AddLinks(links));
+             }).AddLinks(links));
         }
     }
 }

src/SqlStreamStore.HAL/Constants.cs

@@ -60,6 +60,7 @@ public static class Relations
             public const string DeleteStream = StreamStorePrefix + ":delete-stream";
             public const string DeleteMessage = StreamStorePrefix + ":delete-message";
             public const string Find = StreamStorePrefix + ":find";
+            public const string Browse = StreamStorePrefix + ":feed-browser";
         }
 
         public static class Streams
@@ -71,6 +72,7 @@ public static class Streams
             public static PathString AllStreamPath = new PathString($"/{All}");
             public static PathString StreamsPath = new PathString($"/{Stream}");
             public static PathString IndexPath = new PathString("/");
+            public static PathString StreamBrowserPath = StreamsPath;
         }
 
         public static class ReadDirection

src/SqlStreamStore.HAL/Index/IndexResource.cs

@@ -4,7 +4,6 @@ namespace SqlStreamStore.HAL.Index
     using System.Reflection;
     using Halcyon.HAL;
     using Microsoft.AspNetCore.Http;
-    using Newtonsoft.Json;
     using Newtonsoft.Json.Linq;
 
     internal class IndexResource : IResource
@@ -43,8 +42,7 @@ private static string GetVersion(Type type)
                     .FromPath(PathString.Empty)
                     .Index().Self()
                     .Find()
+                    .Browse()
                     .Add(Constants.Relations.Feed, Constants.Streams.All)));
-
-        public override string ToString() => _data.ToString(Formatting.None);
     }
 }

src/SqlStreamStore.HAL/LinksExtensions.cs

@@ -7,5 +7,8 @@ public static Links Index(this Links links) =>
 
         public static Links Find(this Links links)
             => links.Add(Constants.Relations.Find, "streams/{streamId}", "Find a Stream");
+
+        public static Links Browse(this Links links)
+            => links.Add(Constants.Relations.Browse, "streams{?p,t,m}", "Browse Streams");
     }
 }

src/SqlStreamStore.HAL/SqlStreamStoreHalMiddleware.cs

@@ -11,6 +11,7 @@
     using SqlStreamStore.HAL.Docs;
     using SqlStreamStore.HAL.Index;
     using SqlStreamStore.HAL.Logging;
+    using SqlStreamStore.HAL.StreamBrowser;
     using SqlStreamStore.HAL.StreamMessage;
     using SqlStreamStore.HAL.StreamMetadata;
     using SqlStreamStore.HAL.Streams;
@@ -62,6 +63,7 @@ public static IApplicationBuilder UseSqlStreamStoreHal(
             var index = new IndexResource(streamStore);
             var allStream = new AllStreamResource(streamStore, options.UseCanonicalUrls);
             var allStreamMessages = new AllStreamMessageResource(streamStore);
+            var streamBrowser = new StreamBrowserResource(streamStore);
             var streams = new StreamResource(streamStore);
             var streamMetadata = new StreamMetadataResource(streamStore);
             var streamMessages = new StreamMessageResource(streamStore);
@@ -83,6 +85,7 @@ public static IApplicationBuilder UseSqlStreamStoreHal(
                 .UseIndex(index)
                 .UseAllStream(allStream)
                 .UseAllStreamMessage(allStreamMessages)
+                .UseStreamBrowser(streamBrowser)
                 .UseStreams(streams)
                 .UseStreamMetadata(streamMetadata)
                 .UseStreamMessages(streamMessages);

src/SqlStreamStore.HAL/StreamBrowser/ListStreamsOperation.cs

@@ -0,0 +1,58 @@
+namespace SqlStreamStore.HAL.StreamBrowser
+{
+    using System.Threading;
+    using System.Threading.Tasks;
+    using Microsoft.AspNetCore.Http;
+    using SqlStreamStore.Streams;
+
+    internal class ListStreamsOperation : IStreamStoreOperation<ListStreamsPage>
+    {
+        public Pattern Pattern { get; }
+        public string ContinuationToken { get; }
+        public int MaxCount { get; }
+        public string PatternType { get; }
+        public PathString Path { get; }
+
+        public ListStreamsOperation(HttpRequest request)
+        {
+            Path = request.Path;
+            if(request.Query.TryGetValueCaseInsensitive('t', out var patternType))
+            {
+                PatternType = patternType;
+            }
+
+            if(!request.Query.TryGetValueCaseInsensitive('p', out var pattern))
+            {
+                Pattern = Pattern.Anything();
+            }
+            else
+            {
+                switch(PatternType)
+                {
+                    case "s":
+                        Pattern = Pattern.StartsWith(pattern);
+                        break;
+                    case "e":
+                        Pattern = Pattern.EndsWith(pattern);
+                        break;
+                    default:
+                        Pattern = Pattern.Anything();
+                        break;
+                }
+            }
+
+            if(request.Query.TryGetValueCaseInsensitive('c', out var continuationToken))
+            {
+                ContinuationToken = continuationToken;
+            }
+
+            MaxCount = request.Query.TryGetValueCaseInsensitive('m', out var m)
+                       && int.TryParse(m, out var maxCount)
+                ? maxCount
+                : 100;
+        }
+
+        public Task<ListStreamsPage> Invoke(IStreamStore streamStore, CancellationToken cancellationToken)
+            => streamStore.ListStreams(Pattern, MaxCount, ContinuationToken, cancellationToken);
+    }
+}

src/SqlStreamStore.HAL/StreamBrowser/StreamBrowserLinkExtensions.cs

@@ -0,0 +1,37 @@
+namespace SqlStreamStore.HAL.StreamBrowser
+{
+    using SqlStreamStore.Streams;
+
+    internal static class StreamBrowserLinkExtensions
+    {
+        public static Links StreamBrowserNavigation(
+            this Links links,
+            ListStreamsPage listStreamsPage,
+            ListStreamsOperation operation)
+        {
+            if(operation.ContinuationToken != null)
+            {
+                links.Add(
+                    Constants.Relations.Next,
+                    FormatLink(operation, listStreamsPage.ContinuationToken));
+            }
+
+            if(listStreamsPage.ContinuationToken != null)
+            {
+                links.Add(
+                    Constants.Relations.Next,
+                    FormatLink(operation, listStreamsPage.ContinuationToken));
+            }
+
+
+            return links
+                .Add(
+                    Constants.Relations.Browse,
+                    FormatLink(operation, listStreamsPage.ContinuationToken))
+                .Self();
+        }
+
+        private static string FormatLink(ListStreamsOperation operation, string continuationToken) =>
+            $"streams?p={operation.Pattern.Value}&t={operation.PatternType}&c={continuationToken}&m={operation.MaxCount}";
+    }
+}

src/SqlStreamStore.HAL/StreamBrowser/StreamBrowserMiddleware.cs

@@ -0,0 +1,41 @@
+namespace SqlStreamStore.HAL.StreamBrowser
+{
+    using System;
+    using System.Net.Http;
+    using Microsoft.AspNetCore.Builder;
+    using Microsoft.AspNetCore.Http;
+    using MidFunc = System.Func<
+        Microsoft.AspNetCore.Http.HttpContext,
+        System.Func<System.Threading.Tasks.Task>,
+        System.Threading.Tasks.Task
+    >;
+
+    internal static class StreamBrowserMiddleware
+    {
+        public static IApplicationBuilder UseStreamBrowser(
+            this IApplicationBuilder builder,
+            StreamBrowserResource streamBrowser)
+            => builder.MapWhen(IsMatch, Configure(streamBrowser));
+        
+        private static bool IsMatch(HttpContext context)
+            => context.Request.Path.IsStreamBrowser();
+
+        public static bool IsStreamBrowser(this PathString requestPath)
+            => requestPath == Constants.Streams.StreamBrowserPath;
+
+        private static Action<IApplicationBuilder> Configure(StreamBrowserResource streamBrowser)
+            => builder => builder
+                .UseMiddlewareLogging(typeof(StreamBrowserMiddleware))
+                .MapWhen(HttpMethod.Get, inner => inner.Use(BrowseStreams(streamBrowser)));
+
+        private static MidFunc BrowseStreams(StreamBrowserResource streamBrowser)
+            => async (context, next) =>
+            {
+                var response = await streamBrowser.Get(
+                    new ListStreamsOperation(context.Request),
+                    context.RequestAborted);
+
+                await context.WriteResponse(response);
+            };
+    }
+}

src/SqlStreamStore.HAL/StreamBrowser/StreamBrowserResource.cs

@@ -0,0 +1,44 @@
+namespace SqlStreamStore.HAL.StreamBrowser
+{
+    using System;
+    using System.Threading;
+    using System.Threading.Tasks;
+    using Halcyon.HAL;
+    using SqlStreamStore.HAL.StreamBrowser;
+
+    internal class StreamBrowserResource
+    {
+        private readonly IStreamStore _streamStore;
+
+        public StreamBrowserResource(IStreamStore streamStore)
+        {
+            _streamStore = streamStore;
+        }
+
+        public async Task<Response> Get(ListStreamsOperation operation, CancellationToken cancellationToken)
+        {
+            var listStreamsPage = await operation.Invoke(_streamStore, cancellationToken);
+
+            return new HalJsonResponse(new HALResponse(new
+                {
+                    listStreamsPage.ContinuationToken
+                })
+                .AddLinks(
+                    Links
+                        .FromOperation(operation)
+                        .Index()
+                        .Find()
+                        .StreamBrowserNavigation(listStreamsPage, operation))
+                .AddEmbeddedCollection(
+                    Constants.Relations.Feed,
+                    Array.ConvertAll(
+                        listStreamsPage.StreamIds,
+                        streamId => new HALResponse(null)
+                            .AddLinks(
+                                Links
+                                    .FromOperation(operation)
+                                    .Add(Constants.Relations.Feed, $"{Constants.Streams.Stream}/{streamId}", streamId)
+                                    .Self()))));
+        }
+    }
+}