[FAB-2911]Fix JSON-unmarshal for Generic Interface

GOLANG JSON package stores integer in float format.
In fabric Couch DB state ledger code performs a json unmarshalling
on the data wrapper using generic interface data-type.
For JSON document stored in the state ledger that has integer
with digit size >=7; now gets unmarshalled with a E (float) notation which
is eventually passed to the user chain-code upon for eg. shim GetState API.

Unmarshalling at the user-chaincode level result in an error indicating
float cannot be converted to integer type.

To fix this issue, it is neccessary to use NewDecoder API of JSON package
and retains the number representation in such case.

Change-Id: I650cf88dacff84e5e9a185bfa44984a2814488a4
Signed-off-by: rhegde <[email protected]>

Author: rhegde

core/ledger/kvledger/txmgmt/statedb/commontests/test_common.go

@@ -208,20 +208,22 @@ func TestQuery(t *testing.T, dbProvider statedb.VersionedDBProvider) {
 	batch.Put("ns1", "key9", []byte(jsonValue9), version.NewHeight(1, 9))
 	jsonValue10 := "{\"asset_name\": \"marble10\",\"color\": \"green\",\"size\": 10,\"owner\": \"mary\"}"
 	batch.Put("ns1", "key10", []byte(jsonValue10), version.NewHeight(1, 10))
+	jsonValue11 := "{\"asset_name\": \"marble11\",\"color\": \"cyan\",\"size\": 1000007,\"owner\": \"joe\"}"
+	batch.Put("ns1", "key11", []byte(jsonValue11), version.NewHeight(1, 11))
 
 	//add keys for a separate namespace
-	batch.Put("ns2", "key1", []byte(jsonValue1), version.NewHeight(1, 11))
-	batch.Put("ns2", "key2", []byte(jsonValue2), version.NewHeight(1, 12))
-	batch.Put("ns2", "key3", []byte(jsonValue3), version.NewHeight(1, 13))
-	batch.Put("ns2", "key4", []byte(jsonValue4), version.NewHeight(1, 14))
-	batch.Put("ns2", "key5", []byte(jsonValue5), version.NewHeight(1, 15))
-	batch.Put("ns2", "key6", []byte(jsonValue6), version.NewHeight(1, 16))
-	batch.Put("ns2", "key7", []byte(jsonValue7), version.NewHeight(1, 17))
-	batch.Put("ns2", "key8", []byte(jsonValue8), version.NewHeight(1, 18))
-	batch.Put("ns2", "key9", []byte(jsonValue9), version.NewHeight(1, 19))
-	batch.Put("ns2", "key10", []byte(jsonValue10), version.NewHeight(1, 20))
-
-	savePoint := version.NewHeight(2, 21)
+	batch.Put("ns2", "key1", []byte(jsonValue1), version.NewHeight(1, 12))
+	batch.Put("ns2", "key2", []byte(jsonValue2), version.NewHeight(1, 13))
+	batch.Put("ns2", "key3", []byte(jsonValue3), version.NewHeight(1, 14))
+	batch.Put("ns2", "key4", []byte(jsonValue4), version.NewHeight(1, 15))
+	batch.Put("ns2", "key5", []byte(jsonValue5), version.NewHeight(1, 16))
+	batch.Put("ns2", "key6", []byte(jsonValue6), version.NewHeight(1, 17))
+	batch.Put("ns2", "key7", []byte(jsonValue7), version.NewHeight(1, 18))
+	batch.Put("ns2", "key8", []byte(jsonValue8), version.NewHeight(1, 19))
+	batch.Put("ns2", "key9", []byte(jsonValue9), version.NewHeight(1, 20))
+	batch.Put("ns2", "key10", []byte(jsonValue10), version.NewHeight(1, 21))
+
+	savePoint := version.NewHeight(2, 22)
 	db.ApplyUpdates(batch, savePoint)
 
 	// query for owner=jerry, use namespace "ns1"
@@ -435,4 +437,25 @@ func TestQuery(t *testing.T, dbProvider statedb.VersionedDBProvider) {
 	testutil.AssertNoError(t, err, "")
 	testutil.AssertNil(t, queryResult1)
 
+	// query with integer with digit-count equals 7 and response received is also received
+	// with same digit-count and there is no float transformation
+	itr, err = db.ExecuteQuery("ns1", "{\"selector\":{\"$and\":[{\"size\":{\"$eq\": 1000007}}]}}")
+	testutil.AssertNoError(t, err, "")
+
+	// verify one jerry result
+	queryResult1, err = itr.Next()
+	testutil.AssertNoError(t, err, "")
+	testutil.AssertNotNil(t, queryResult1)
+	versionedQueryRecord = queryResult1.(*statedb.VersionedQueryRecord)
+	stringRecord = string(versionedQueryRecord.Record)
+	bFoundRecord = strings.Contains(stringRecord, "joe")
+	testutil.AssertEquals(t, bFoundRecord, true)
+	bFoundRecord = strings.Contains(stringRecord, "1000007")
+	testutil.AssertEquals(t, bFoundRecord, true)
+
+	// verify no more results
+	queryResult2, err = itr.Next()
+	testutil.AssertNoError(t, err, "")
+	testutil.AssertNil(t, queryResult2)
+
 }

core/ledger/kvledger/txmgmt/statedb/statecouchdb/query_wrapper.go

@@ -17,6 +17,7 @@ limitations under the License.
 package statecouchdb
 
 import (
+	"bytes"
 	"encoding/json"
 	"fmt"
 	"reflect"
@@ -66,7 +67,9 @@ func ApplyQueryWrapper(namespace, queryString string, queryLimit, querySkip int)
 	jsonQueryMap := make(map[string]interface{})
 
 	//unmarshal the selected json into the generic map
-	err := json.Unmarshal([]byte(queryString), &jsonQueryMap)
+	decoder := json.NewDecoder(bytes.NewBuffer([]byte(queryString)))
+	decoder.UseNumber()
+	err := decoder.Decode(&jsonQueryMap)
 	if err != nil {
 		return "", err
 	}
@@ -167,6 +170,10 @@ func processAndWrapQuery(jsonQueryMap map[string]interface{}) {
 			//intercept the float64 case and prevent the []interface{} case from
 			//incorrectly processing the float64
 
+		case json.Number:
+			//intercept the Number case and prevent the []interface{} case from
+			//incorrectly processing the float64
+
 		//if the type is an array, then iterate through the items
 		case []interface{}:
 

core/ledger/kvledger/txmgmt/statedb/statecouchdb/query_wrapper_test.go

@@ -366,3 +366,18 @@ func TestQueryWithUseDesignDocAndIndexName(t *testing.T) {
 	testutil.AssertEquals(t, strings.Count(wrappedQuery, "\"use_index\":[\"_design/testDoc\",\"testIndexName\"]"), 1)
 
 }
+
+//TestQueryWithLargeInteger tests query with large integer
+func TestQueryWithLargeInteger(t *testing.T) {
+
+	rawQuery := []byte(`{"selector":{"$and":[{"size":{"$eq": 1000007}}]}}`)
+
+	wrappedQuery, err := ApplyQueryWrapper("ns1", string(rawQuery), 10000, 0)
+
+	//Make sure the query did not throw an exception
+	testutil.AssertNoError(t, err, "Unexpected error thrown when for query JSON")
+
+	//check to make sure the default selector is added
+	testutil.AssertEquals(t, strings.Count(wrappedQuery, "{\"$eq\":1000007}"), 1)
+
+}

core/ledger/kvledger/txmgmt/statedb/statecouchdb/statecouchdb.go

@@ -144,7 +144,9 @@ func removeDataWrapper(wrappedValue []byte, attachments []couchdb.Attachment) ([
 	jsonResult := make(map[string]interface{})
 
 	//unmarshal the selected json into the generic map
-	json.Unmarshal(wrappedValue, &jsonResult)
+	decoder := json.NewDecoder(bytes.NewBuffer(wrappedValue))
+	decoder.UseNumber()
+	_ = decoder.Decode(&jsonResult)
 
 	// handle binary or json data
 	if jsonResult[dataWrapper] == nil && attachments != nil { // binary attachment

core/ledger/util/couchdb/couchdb.go

@@ -504,8 +504,11 @@ func createAttachmentPart(couchDoc *CouchDoc, defaultBoundary string) (bytes.Buf
 
 		//create a generic map
 		genericMap := make(map[string]interface{})
+
 		//unmarshal the data into the generic map
-		json.Unmarshal(couchDoc.JSONValue, &genericMap)
+		decoder := json.NewDecoder(bytes.NewBuffer(couchDoc.JSONValue))
+		decoder.UseNumber()
+		decoder.Decode(&genericMap)
 
 		//add all key/values to the attachmentJSONMap
 		for jsonKey, jsonValue := range genericMap {