Convert SearchResult to JSON (#87)

* Add ToJson() in SearchResult + example & test

* add Where not null

* add assertion

* fixes

Author: shacharPash

Examples/ConvertSearchResultToJson.md

@@ -0,0 +1,31 @@
+# Converting Search Result to JSON
+## This example shows how to convert Redis search results to JSON format using NRedisStack.
+
+Connect to the Redis server:
+```csharp
+var redis = ConnectionMultiplexer.Connect("localhost");
+```
+Get a reference to the database and for search and json commands:
+```csharp
+var db = redis.GetDatabase();
+var ft = db.FT();
+var json = db.JSON();
+```
+Create a search index with a JSON field:
+```csharp
+ft.Create("test", new FTCreateParams().On(IndexDataType.JSON).Prefix("doc:"),
+            new Schema().AddTagField(new FieldName("$.name", "name")));
+```
+Insert 10 JSON documents into the index:
+```csharp
+for (int i = 0; i < 10; i++)
+{
+    json.Set("doc:" + i, "$", "{\"name\":\"foo\"}");
+}
+```
+Execute a search query and convert the results to JSON:
+```csharp
+var res = ft.Search("test", new Query("@name:{foo}"));
+var docs = res.ToJson();
+```
+Now the `docs` variable contains a JSON list (IEnumerable) of the search results.

src/NRedisStack/Search/SearchResult.cs

@@ -12,6 +12,12 @@ public class SearchResult
         public long TotalResults { get; }
         public List<Document> Documents { get; }
 
+        /// <summary>
+        /// Converts the documents to a list of json strings. only works on a json documents index.
+        /// </summary>
+        public IEnumerable<string>? ToJson() => Documents.Select(x => x["json"].ToString())
+                                                         .Where(x => !string.IsNullOrEmpty(x));
+
         internal SearchResult(RedisResult[] resp, bool hasContent, bool hasScores, bool hasPayloads/*, bool shouldExplainScore*/)
         {
             // Calculate the step distance to walk over the results.

tests/NRedisStack.Tests/Examples/ExamplesTests.cs

@@ -61,6 +61,10 @@ public void HSETandSearch()
         // Search for hashes with last name of Rod
         var lastNameRod = ft.Search("example_index", new Query("@last:Rod"));
         // lastNameRod is empty because there are no hashes with a last name of Rod that match the index definition
+        Assert.Equal(4, noFilters.TotalResults);
+        Assert.Equal(2, startWithJo.TotalResults);
+        Assert.Equal(1, namedPat.TotalResults);
+        Assert.Equal(0, lastNameRod.TotalResults);
     }
 
     [Fact]
@@ -226,7 +230,7 @@ public async Task TransactionExample()
         var tran = new Transaction(db);
 
         // Add account details with Json.Set to transaction
-        tran.Json.SetAsync("accdetails:Jeeva", "$", new { name = "Jeeva", totalAmount= 1000, bankName = "City" });
+        tran.Json.SetAsync("accdetails:Jeeva", "$", new { name = "Jeeva", totalAmount = 1000, bankName = "City" });
         tran.Json.SetAsync("accdetails:Shachar", "$", new { name = "Shachar", totalAmount = 1000, bankName = "City" });
 
         // Get the Json response
@@ -240,8 +244,8 @@ public async Task TransactionExample()
         tran.Json.NumIncrbyAsync("accdetails:Shachar", "$.totalAmount", 200);
 
         // Get total amount for both Jeeva = 800 & Shachar = 1200
-        var totalAmtOfJeeva = tran.Json.GetAsync("accdetails:Jeeva", path:"$.totalAmount");
-        var totalAmtOfShachar = tran.Json.GetAsync("accdetails:Shachar", path:"$.totalAmount");
+        var totalAmtOfJeeva = tran.Json.GetAsync("accdetails:Jeeva", path: "$.totalAmount");
+        var totalAmtOfShachar = tran.Json.GetAsync("accdetails:Shachar", path: "$.totalAmount");
 
         // Execute the transaction
         var condition = tran.ExecuteAsync();
@@ -253,4 +257,26 @@ public async Task TransactionExample()
         Assert.Equal("[800]", totalAmtOfJeeva.Result.ToString());
         Assert.Equal("[1200]", totalAmtOfShachar.Result.ToString());
     }
+
+    [Fact]
+    public void TestJsonConvert()
+    {
+        ConnectionMultiplexer redis = ConnectionMultiplexer.Connect("localhost");
+        IDatabase db = redis.GetDatabase();
+        db.Execute("FLUSHALL");
+        ISearchCommands ft = db.FT();
+        IJsonCommands json = db.JSON();
+
+        ft.Create("test", new FTCreateParams().On(IndexDataType.JSON).Prefix("doc:"),
+            new Schema().AddTagField(new FieldName("$.name", "name")));
+        for (int i = 0; i < 10; i++)
+        {
+            json.Set("doc:" + i, "$", "{\"name\":\"foo\"}");
+        }
+        var res = ft.Search("test", new Query("@name:{foo}"));
+
+        var docs = res.ToJson();
+
+        Assert.Equal(10, docs.Count());
+    }
 }