Merge pull request #165 from marklagendijk/master

Implemented preset support

Author: JimBobSquarePants

src/ImageSharp.Web/Commands/PresetOnlyQueryCollectionRequestParser.cs

@@ -0,0 +1,64 @@
+// Copyright (c) Six Labors.
+// Licensed under the Apache License, Version 2.0.
+
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using Microsoft.AspNetCore.Http;
+using Microsoft.AspNetCore.WebUtilities;
+using Microsoft.Extensions.Options;
+using Microsoft.Extensions.Primitives;
+
+namespace SixLabors.ImageSharp.Web.Commands
+{
+    /// <summary>
+    /// Parses preset name from the request querystring and returns the commands configured for that preset.
+    /// </summary>
+    public class PresetOnlyQueryCollectionRequestParser : IRequestParser
+    {
+        private readonly IDictionary<string, IDictionary<string, string>> presets;
+
+        /// <summary>
+        /// The command constant for the preset query parameter.
+        /// </summary>
+        public const string QueryKey = "preset";
+
+        /// <summary>
+        /// Initializes a new instance of the <see cref="PresetOnlyQueryCollectionRequestParser"/> class.
+        /// </summary>
+        /// <param name="presetOptions">The preset options.</param>
+        public PresetOnlyQueryCollectionRequestParser(IOptions<PresetOnlyQueryCollectionRequestParserOptions> presetOptions) =>
+            this.presets = ParsePresets(presetOptions.Value.Presets);
+
+        /// <inheritdoc/>
+        public IDictionary<string, string> ParseRequestCommands(HttpContext context)
+        {
+            if (context.Request.Query.Count == 0 || !context.Request.Query.ContainsKey(QueryKey))
+            {
+                return new Dictionary<string, string>(StringComparer.OrdinalIgnoreCase);
+            }
+
+            var requestedPreset = context.Request.Query["preset"][0];
+            return this.presets.GetValueOrDefault(requestedPreset) ?? new Dictionary<string, string>(StringComparer.OrdinalIgnoreCase);
+        }
+
+        private static IDictionary<string, IDictionary<string, string>> ParsePresets(
+            IDictionary<string, string> unparsedPresets) =>
+            unparsedPresets
+                .Select(keyValue =>
+                    new KeyValuePair<string, IDictionary<string, string>>(keyValue.Key, ParsePreset(keyValue.Value)))
+                .ToDictionary(keyValue => keyValue.Key, keyValue => keyValue.Value, StringComparer.OrdinalIgnoreCase);
+
+        private static IDictionary<string, string> ParsePreset(string unparsedPresetValue)
+        {
+            Dictionary<string, StringValues> parsed = QueryHelpers.ParseQuery(unparsedPresetValue);
+            var transformed = new Dictionary<string, string>(parsed.Count, StringComparer.OrdinalIgnoreCase);
+            foreach (KeyValuePair<string, StringValues> keyValue in parsed)
+            {
+                transformed[keyValue.Key] = keyValue.Value.ToString();
+            }
+
+            return transformed;
+        }
+    }
+}

src/ImageSharp.Web/Commands/PresetOnlyQueryCollectionRequestParserOptions.cs

@@ -0,0 +1,18 @@
+// Copyright (c) Six Labors.
+// Licensed under the Apache License, Version 2.0.
+
+using System.Collections.Generic;
+
+namespace SixLabors.ImageSharp.Web.Commands
+{
+    /// <summary>
+    /// Configuration options for the <see cref="PresetOnlyQueryCollectionRequestParser"/>.
+    /// </summary>
+    public class PresetOnlyQueryCollectionRequestParserOptions
+    {
+        /// <summary>
+        /// Gets or sets the presets, which is a Dictionary of preset names to command query strings.
+        /// </summary>
+        public IDictionary<string, string> Presets { get; set; } = new Dictionary<string, string>();
+    }
+}

src/ImageSharp.Web/Commands/QueryCollectionRequestParser.cs

@@ -23,7 +23,7 @@ public IDictionary<string, string> ParseRequestCommands(HttpContext context)
             }
 
             Dictionary<string, StringValues> parsed = QueryHelpers.ParseQuery(context.Request.QueryString.ToUriComponent());
-            var transformed = new Dictionary<string, string>(parsed.Count);
+            var transformed = new Dictionary<string, string>(parsed.Count, StringComparer.OrdinalIgnoreCase);
             foreach (KeyValuePair<string, StringValues> pair in parsed)
             {
                 transformed[pair.Key] = pair.Value.ToString();

tests/ImageSharp.Web.Tests/Commands/PresetOnlyQueryCollectionRequestParserTests.cs

@@ -0,0 +1,100 @@
+// Copyright (c) Six Labors.
+// Licensed under the Apache License, Version 2.0.
+
+using System;
+using System.Collections.Generic;
+using Microsoft.AspNetCore.Http;
+using Microsoft.Extensions.Options;
+using SixLabors.ImageSharp.Web.Commands;
+using Xunit;
+
+namespace SixLabors.ImageSharp.Web.Tests.Commands
+{
+    public class PresetOnlyQueryCollectionRequestParserTests
+    {
+        [Fact]
+        public void PresetOnlyQueryCollectionRequestParserExtractsCommands()
+        {
+            IDictionary<string, string> expected = new Dictionary<string, string>(StringComparer.OrdinalIgnoreCase)
+            {
+                { "width", "400" },
+                { "height", "200" }
+            };
+
+            HttpContext context = CreateHttpContext("?preset=Preset1");
+            IDictionary<string, string> actual = new PresetOnlyQueryCollectionRequestParser(Options.Create(new PresetOnlyQueryCollectionRequestParserOptions
+            {
+                Presets = new Dictionary<string, string>(StringComparer.OrdinalIgnoreCase)
+                {
+                    { "Preset1", "width=400&height=200" }
+                }
+            })).ParseRequestCommands(context);
+
+            Assert.Equal(expected, actual);
+        }
+
+        [Fact]
+        public void PresetOnlyQueryCollectionRequestParserExtractsCommandsWithOtherCasing()
+        {
+            IDictionary<string, string> expected = new Dictionary<string, string>(StringComparer.OrdinalIgnoreCase)
+            {
+                { "width", "400" },
+                { "height", "200" }
+            };
+
+            HttpContext context = CreateHttpContext("?PRESET=PRESET1");
+            IDictionary<string, string> actual = new PresetOnlyQueryCollectionRequestParser(Options.Create(new PresetOnlyQueryCollectionRequestParserOptions
+            {
+                Presets = new Dictionary<string, string>(StringComparer.OrdinalIgnoreCase)
+                {
+                    { "Preset1", "width=400&height=200" }
+                }
+            })).ParseRequestCommands(context);
+
+            Assert.Equal(expected, actual);
+        }
+
+
+        [Fact]
+        public void PresetOnlyQueryCollectionRequestParserCommandsWithoutPresetParam()
+        {
+            IDictionary<string, string> expected = new Dictionary<string, string>();
+
+            HttpContext context = CreateHttpContext("?test=test");
+            IDictionary<string, string> actual = new PresetOnlyQueryCollectionRequestParser(Options.Create(new PresetOnlyQueryCollectionRequestParserOptions
+            {
+                Presets = new Dictionary<string, string>(StringComparer.OrdinalIgnoreCase)
+                {
+                    { "Preset1", "width=400&height=200" }
+                }
+            })).ParseRequestCommands(context);
+
+            Assert.Equal(expected, actual);
+        }
+
+        [Fact]
+        public void PresetOnlyQueryCollectionRequestParserCommandsWithoutMatchingPreset()
+        {
+            IDictionary<string, string> expected = new Dictionary<string, string>();
+
+            HttpContext context = CreateHttpContext("?preset=Preset2");
+            IDictionary<string, string> actual = new PresetOnlyQueryCollectionRequestParser(Options.Create(new PresetOnlyQueryCollectionRequestParserOptions
+            {
+                Presets = new Dictionary<string, string>(StringComparer.OrdinalIgnoreCase)
+                {
+                    { "Preset1", "width=400&height=200" }
+                }
+            })).ParseRequestCommands(context);
+
+            Assert.Equal(expected, actual);
+        }
+
+        private static HttpContext CreateHttpContext(string query)
+        {
+            var httpContext = new DefaultHttpContext();
+            httpContext.Request.Path = "/testwebsite.com/image-12345.jpeg";
+            httpContext.Request.QueryString = new QueryString(query);
+            return httpContext;
+        }
+    }
+}