From 85fb8cfa8698e93559891b4cb3a6b02c875991ce Mon Sep 17 00:00:00 2001
From: Kenneth Myhra <kennethmyhra@gmail.com>
Date: Sun, 5 Sep 2021 12:20:48 +0200
Subject: [PATCH] feature: Add GET interaction support for transaction bundles

This adds support for GET interaction in batch/transaction bundles.

Fixes #305
---
 src/Spark.Engine/Core/Interaction.cs          |  5 +++
 .../GetManipulationOperation.cs               | 38 +++++++++++++++++++
 .../ResourceManipulationOperationFactory.cs   | 20 +++++++++-
 3 files changed, 61 insertions(+), 2 deletions(-)
 create mode 100644 src/Spark.Engine/Service/FhirServiceExtensions/GetManipulationOperation.cs

diff --git a/src/Spark.Engine/Core/Interaction.cs b/src/Spark.Engine/Core/Interaction.cs
index 3fba9d2a9..a0518961d 100644
--- a/src/Spark.Engine/Core/Interaction.cs
+++ b/src/Spark.Engine/Core/Interaction.cs
@@ -89,6 +89,11 @@ public static Entry Create(Bundle.HTTPVerb method, Resource resource)
             return new Entry(method, null, null, resource);
         }
 
+        public static Entry Create(Bundle.HTTPVerb method, IKey key)
+        {
+            return new Entry(method, key, null, null);
+        }
+
         public static Entry Create(Bundle.HTTPVerb method, IKey key, Resource resource)
         {
             return new Entry(method, key, null, resource);
diff --git a/src/Spark.Engine/Service/FhirServiceExtensions/GetManipulationOperation.cs b/src/Spark.Engine/Service/FhirServiceExtensions/GetManipulationOperation.cs
new file mode 100644
index 000000000..a19d9f69a
--- /dev/null
+++ b/src/Spark.Engine/Service/FhirServiceExtensions/GetManipulationOperation.cs
@@ -0,0 +1,38 @@
+using Hl7.Fhir.Model;
+using Hl7.Fhir.Rest;
+using Spark.Engine.Core;
+using System;
+using System.Collections.Generic;
+
+namespace Spark.Engine.Service.FhirServiceExtensions
+{
+    public class GetManipulationOperation : ResourceManipulationOperation
+    {
+        public GetManipulationOperation(Resource resource, IKey operationKey, SearchResults searchResults, SearchParams searchCommand = null) 
+            : base(resource, operationKey, searchResults, searchCommand)
+        {
+        }
+        
+        public static Uri ReadSearchUri(Bundle.EntryComponent entry)
+        {
+            return entry.Request != null
+                ? new Uri(entry.Request.Url, UriKind.RelativeOrAbsolute)
+                : null;
+        }
+
+        protected override IEnumerable<Entry> ComputeEntries()
+        {
+            if (SearchResults != null)
+            {
+                foreach (string localKeyLiteral in SearchResults)
+                {
+                    yield return Entry.Create(Bundle.HTTPVerb.GET, Key.ParseOperationPath(localKeyLiteral));
+                }
+            }
+            else
+            {
+                yield return Entry.Create(Bundle.HTTPVerb.GET, OperationKey);
+            }
+        }
+    }
+}
\ No newline at end of file
diff --git a/src/Spark.Engine/Service/FhirServiceExtensions/ResourceManipulationOperationFactory.cs b/src/Spark.Engine/Service/FhirServiceExtensions/ResourceManipulationOperationFactory.cs
index 81ab34470..302341aa9 100644
--- a/src/Spark.Engine/Service/FhirServiceExtensions/ResourceManipulationOperationFactory.cs
+++ b/src/Spark.Engine/Service/FhirServiceExtensions/ResourceManipulationOperationFactory.cs
@@ -22,14 +22,16 @@ static ResourceManipulationOperationFactory()
             {
                 { Bundle.HTTPVerb.POST, CreatePost },
                 { Bundle.HTTPVerb.PUT, CreatePut },
-                { Bundle.HTTPVerb.DELETE, CreateDelete }
+                { Bundle.HTTPVerb.DELETE, CreateDelete },
+                { Bundle.HTTPVerb.GET, CreateGet },
             };
             
             _asyncBuilders = new Dictionary<Bundle.HTTPVerb, Func<Resource, IKey, ISearchService, SearchParams, Task<ResourceManipulationOperation>>>
             {
                 { Bundle.HTTPVerb.POST, CreatePostAsync },
                 { Bundle.HTTPVerb.PUT, CreatePutAsync },
-                { Bundle.HTTPVerb.DELETE, CreateDeleteAsync }
+                { Bundle.HTTPVerb.DELETE, CreateDeleteAsync },
+                { Bundle.HTTPVerb.GET, CreateGetAsync },
             };
         }
 
@@ -91,6 +93,16 @@ private static async Task<ResourceManipulationOperation> CreateDeleteAsync(Resou
             return new DeleteManipulationOperation(null, key, await GetSearchResultAsync(key, searchService, searchParams).ConfigureAwait(false), searchParams);
         }
 
+        private static ResourceManipulationOperation CreateGet(Resource resource, IKey key, ISearchService searchService, SearchParams searchParams)
+        {
+            return new GetManipulationOperation(resource, key, GetSearchResult(key, searchService, searchParams), searchParams);
+        }
+
+        private static async Task<ResourceManipulationOperation> CreateGetAsync(Resource resource, IKey key, ISearchService searchService, SearchParams searchParams)
+        {
+            return new GetManipulationOperation(resource, key, await GetSearchResultAsync(key, searchService, searchParams), searchParams);
+        }
+
         public static ResourceManipulationOperation GetManipulationOperation(Bundle.EntryComponent entryComponent, ILocalhost localhost, ISearchService searchService = null)
         {
             Bundle.HTTPVerb method = localhost.ExtrapolateMethod(entryComponent, null);
@@ -127,6 +139,10 @@ private static Uri GetSearchUri(Bundle.EntryComponent entryComponent, Bundle.HTT
             {
                 searchUri = DeleteManipulationOperation.ReadSearchUri(entryComponent);
             }
+            else if (method == Bundle.HTTPVerb.GET)
+            {
+                searchUri = FhirServiceExtensions.GetManipulationOperation.ReadSearchUri(entryComponent);
+            }
             return searchUri;
         }