fix formatting to json of Map type with integer keys

src/DataTypes/Serializations/SerializationMap.cpp

@@ -81,7 +81,7 @@ void SerializationMap::deserializeBinary(IColumn & column, ReadBuffer & istr) co
 
 
 template <typename Writer>
-void SerializationMap::serializeTextImpl(const IColumn & column, size_t row_num, WriteBuffer & ostr, Writer && writer) const
+void SerializationMap::serializeTextImpl(const IColumn & column, size_t row_num, bool quote_key, WriteBuffer & ostr, Writer && writer) const
 {
     const auto & column_map = assert_cast<const ColumnMap &>(column);
 
@@ -97,7 +97,16 @@ void SerializationMap::serializeTextImpl(const IColumn & column, size_t row_num,
     {
         if (i != offset)
             writeChar(',', ostr);
-        writer(key, nested_tuple.getColumn(0), i);
+
+        if (quote_key)
+        {
+            writeChar('"', ostr);
+            writer(key, nested_tuple.getColumn(0), i);
+            writeChar('"', ostr);
+        }
+        else
+            writer(key, nested_tuple.getColumn(0), i);
+
         writeChar(':', ostr);
         writer(value, nested_tuple.getColumn(1), i);
     }
@@ -161,7 +170,7 @@ void SerializationMap::deserializeTextImpl(IColumn & column, ReadBuffer & istr,
 
 void SerializationMap::serializeText(const IColumn & column, size_t row_num, WriteBuffer & ostr, const FormatSettings & settings) const
 {
-    serializeTextImpl(column, row_num, ostr,
+    serializeTextImpl(column, row_num, /*quote_key=*/ false, ostr,
         [&](const SerializationPtr & subcolumn_serialization, const IColumn & subcolumn, size_t pos)
         {
             subcolumn_serialization->serializeTextQuoted(subcolumn, pos, ostr, settings);
@@ -170,7 +179,6 @@ void SerializationMap::serializeText(const IColumn & column, size_t row_num, Wri
 
 void SerializationMap::deserializeText(IColumn & column, ReadBuffer & istr, const FormatSettings & settings) const
 {
-
     deserializeTextImpl(column, istr,
         [&](const SerializationPtr & subcolumn_serialization, IColumn & subcolumn)
         {
@@ -178,10 +186,13 @@ void SerializationMap::deserializeText(IColumn & column, ReadBuffer & istr, cons
         });
 }
 
-
 void SerializationMap::serializeTextJSON(const IColumn & column, size_t row_num, WriteBuffer & ostr, const FormatSettings & settings) const
 {
-    serializeTextImpl(column, row_num, ostr,
+    /// We need to double-quote integer keys to produce valid JSON.
+    const auto & column_key = assert_cast<const ColumnMap &>(column).getNestedData().getColumn(0);
+    bool quote_key = !WhichDataType(column_key.getDataType()).isStringOrFixedString();
+
+    serializeTextImpl(column, row_num, quote_key, ostr,
         [&](const SerializationPtr & subcolumn_serialization, const IColumn & subcolumn, size_t pos)
         {
             subcolumn_serialization->serializeTextJSON(subcolumn, pos, ostr, settings);

src/DataTypes/Serializations/SerializationMap.h

@@ -61,7 +61,7 @@ public:
 
 private:
     template <typename Writer>
-    void serializeTextImpl(const IColumn & column, size_t row_num, WriteBuffer & ostr, Writer && writer) const;
+    void serializeTextImpl(const IColumn & column, size_t row_num, bool quote_key, WriteBuffer & ostr, Writer && writer) const;
 
     template <typename Reader>
     void deserializeTextImpl(IColumn & column, ReadBuffer & istr, Reader && reader) const;

src/Functions/toJSONString.cpp

@@ -2,6 +2,7 @@
 #include <DataTypes/DataTypeString.h>
 #include <Functions/FunctionFactory.h>
 #include <Functions/IFunction.h>
+#include <Formats/FormatFactory.h>
 #include <IO/WriteBufferFromVector.h>
 #include <IO/WriteHelpers.h>
 
@@ -13,7 +14,9 @@ namespace
     {
     public:
         static constexpr auto name = "toJSONString";
-        static FunctionPtr create(ContextPtr) { return std::make_shared<FunctionToJSONString>(); }
+        static FunctionPtr create(ContextPtr context) { return std::make_shared<FunctionToJSONString>(context); }
+
+        FunctionToJSONString(ContextPtr context) : format_settings(getFormatSettings(context)) {}
 
         String getName() const override { return name; }
 
@@ -35,7 +38,7 @@ namespace
             WriteBufferFromVector<ColumnString::Chars> json(data_to);
             for (size_t i = 0; i < input_rows_count; ++i)
             {
-                serializer->serializeTextJSON(*arguments[0].column, i, json, FormatSettings());
+                serializer->serializeTextJSON(*arguments[0].column, i, json, format_settings);
                 writeChar(0, json);
                 offsets_to[i] = json.count();
             }
@@ -43,6 +46,10 @@ namespace
             json.finalize();
             return res;
         }
+
+    private:
+        /// Affects only subset of part of settings related to json.
+        FormatSettings format_settings;
     };
 }
 

tests/queries/0_stateless/01939_type_map_json.reference

@@ -0,0 +1,8 @@
+{"m":{"1":2,"3":4}}
+{1:2,3:4}	{"1":2,"3":4}	1
+{"m":{"key1":"1","key2":"2"}}
+{'key1':1,'key2':2}	{"key1":"1","key2":"2"}	1
+{"m":{"key1":1,"key2":2}}
+{'key1':1,'key2':2}	{"key1":1,"key2":2}	1
+{"m1":{"k1":"1","k2":"2"},"m2":{"1":2,"2":3}}
+{"m1":{"k1":1,"k2":2},"m2":{"1":2,"2":3}}

tests/queries/0_stateless/01939_type_map_json.sql

@@ -0,0 +1,19 @@
+SELECT map(1, 2, 3, 4) AS m FORMAT JSONEachRow;
+SELECT map(1, 2, 3, 4) AS m, toJSONString(m) AS s, isValidJSON(s);
+
+SELECT map('key1', number, 'key2', number * 2) AS m FROM numbers(1, 1) FORMAT JSONEachRow;
+SELECT map('key1', number, 'key2', number * 2) AS m, toJSONString(m) AS s, isValidJSON(s) FROM numbers(1, 1);
+
+SELECT map('key1', number, 'key2', number * 2) AS m FROM numbers(1, 1)
+    FORMAT JSONEachRow
+    SETTINGS output_format_json_quote_64bit_integers = 0;
+
+SELECT map('key1', number, 'key2', number * 2) AS m, toJSONString(m) AS s, isValidJSON(s) FROM numbers(1, 1)
+    SETTINGS output_format_json_quote_64bit_integers = 0;
+
+CREATE TEMPORARY TABLE map_json (m1 Map(String, UInt64), m2 Map(UInt32, UInt32));
+
+INSERT INTO map_json FORMAT JSONEachRow {"m1" : {"k1" : 1, "k2" : 2}, "m2" : {"1" : 2, "2" : 3}};
+
+SELECT m1, m2 FROM map_json FORMAT JSONEachRow;
+SELECT m1, m2 FROM map_json FORMAT JSONEachRow SETTINGS output_format_json_quote_64bit_integers = 0;