Fix serialization of suggester with context queries

Context queries of a suggester need to be serializes as a dictionary,
not an array.

See #329

CONTRIBUTORS

@@ -59,3 +59,4 @@ TimeEmit [@TimeEmit](https://github.com/timeemit)
 TusharM [@tusharm](https://github.com/tusharm)
 wolfkdy [@wolfkdy](https://github.com/wolfkdy)
 zakthomas [@zakthomas](https://github.com/zakthomas)
+singham [@zhaochenxiao90](https://github.com/zhaochenxiao90)

client.go

@@ -21,7 +21,7 @@ import (
 
 const (
 	// Version is the current version of Elastic.
-	Version = "3.0.44"
+	Version = "3.0.45"
 
 	// DefaultUrl is the default endpoint of Elasticsearch on the local machine.
 	// It is used e.g. when initializing a new Client without a specific URL.

suggester_completion.go

@@ -4,6 +4,8 @@
 
 package elastic
 
+import "errors"
+
 // CompletionSuggester is a fast suggester for e.g. type-ahead completion.
 // See http://www.elasticsearch.org/guide/en/elasticsearch/reference/current/search-suggesters-completion.html
 // for more details.
@@ -74,7 +76,7 @@ type completionSuggesterRequest struct {
 	Completion interface{} `json:"completion"`
 }
 
-// Creates the source for the completion suggester.
+// Source creates the JSON structure for the completion suggester.
 func (q *CompletionSuggester) Source(includeName bool) (interface{}, error) {
 	cs := &completionSuggesterRequest{}
 
@@ -106,13 +108,20 @@ func (q *CompletionSuggester) Source(includeName bool) (interface{}, error) {
 		}
 		suggester["context"] = src
 	default:
-		ctxq := make([]interface{}, 0)
+		ctxq := make(map[string]interface{})
 		for _, query := range q.contextQueries {
 			src, err := query.Source()
 			if err != nil {
 				return nil, err
 			}
-			ctxq = append(ctxq, src)
+			// Merge the dictionary into ctxq
+			m, ok := src.(map[string]interface{})
+			if !ok {
+				return nil, errors.New("elastic: context query is not a map")
+			}
+			for k, v := range m {
+				ctxq[k] = v
+			}
 		}
 		suggester["context"] = ctxq
 	}

suggester_completion_test.go

@@ -27,3 +27,26 @@ func TestCompletionSuggesterSource(t *testing.T) {
 		t.Errorf("expected\n%s\n,got:\n%s", expected, got)
 	}
 }
+
+func TestCompletionSuggesterSourceWithMultipleContexts(t *testing.T) {
+	s := NewCompletionSuggester("song-suggest").
+		Text("n").
+		Field("suggest").
+		ContextQueries(
+			NewSuggesterCategoryQuery("artist", "Sting"),
+			NewSuggesterCategoryQuery("label", "BMG"),
+		)
+	src, err := s.Source(true)
+	if err != nil {
+		t.Fatal(err)
+	}
+	data, err := json.Marshal(src)
+	if err != nil {
+		t.Fatalf("marshaling to JSON failed: %v", err)
+	}
+	got := string(data)
+	expected := `{"song-suggest":{"text":"n","completion":{"context":{"artist":"Sting","label":"BMG"},"field":"suggest"}}}`
+	if got != expected {
+		t.Errorf("expected\n%s\n,got:\n%s", expected, got)
+	}
+}