FAB-2263 GetQueryResult should support index name

Motivation for this change:
In CouchDB _find API, use_index parameter can specify which index
to utilize for the query. Change the query wrapper to accept the
"use-index" parameter.

This change can be accomplished using existing JSON query formatting.

-  Change query wrapper to allow "use_index" correctly

-  Changes have been made to the marbles02 example to demonstrate
queries using specific indexes.

-  Change Vagrantfile to add a "couchdb" alias to the vagrant
host file.  This will allow REST API calls to be consistent
between vagrant and docker images.

Change-Id: Ie54750ccc5ccf8aa01192168b60354f0984c5676
Signed-off-by: Chris Elder <[email protected]>

Author: Chris Elder

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

@@ -22,9 +22,10 @@ import (
 	"reflect"
 )
 
-var dataWrapper = "data"
-var jsonQueryFields = "fields"
-var jsonQuerySelector = "selector"
+const dataWrapper = "data"
+const jsonQueryFields = "fields"
+const jsonQuerySelector = "selector"
+const jsonQueryUseIndex = "use_index"
 
 var validOperators = []string{"$and", "$or", "$not", "$nor", "$all", "$elemMatch",
 	"$lt", "$lte", "$eq", "$ne", "$gte", "$gt", "$exits", "$type", "$in", "$nin",
@@ -37,7 +38,8 @@ All fields in the selector must have "data." prepended to the field names
 Fields listed in fields key will have "data." prepended
 Fields in the sort key will have "data." prepended
 
-Also,  the query will be scoped to the chaincodeid if the contextID is supplied
+Also,  the query will be scoped to the chaincodeid
+
 In the example a contextID of "marble" is assumed.
 
 Example:
@@ -67,13 +69,12 @@ func ApplyQueryWrapper(namespace, queryString string) (string, error) {
 	//traverse through the json query and wrap any field names
 	processAndWrapQuery(jsonQueryMap)
 
-	//if "fields" are specified in the query, the add the "_id", "version" and "chaincodeid" fields
+	//if "fields" are specified in the query, then add the "_id", "version" and "chaincodeid" fields
 	if jsonValue, ok := jsonQueryMap[jsonQueryFields]; ok {
 		//check to see if this is an interface map
 		if reflect.TypeOf(jsonValue).String() == "[]interface {}" {
 
-			//Add the "_id" and "version" fields,  these are needed by default
-			//Overwrite the query fields if the "_id" field has been added
+			//Add the "_id", "version" and "chaincodeid" fields,  these are needed by default
 			jsonQueryMap[jsonQueryFields] = append(jsonValue.([]interface{}),
 				"_id", "version", "chaincodeid")
 		}
@@ -142,7 +143,7 @@ func setDefaultNamespaceInSelector(namespace string, jsonQueryMap map[string]int
 func processAndWrapQuery(jsonQueryMap map[string]interface{}) {
 
 	//iterate through the JSON query
-	for _, jsonValue := range jsonQueryMap {
+	for jsonKey, jsonValue := range jsonQueryMap {
 
 		//create a case for the data types found in the JSON query
 		switch jsonValueType := jsonValue.(type) {
@@ -165,8 +166,11 @@ func processAndWrapQuery(jsonQueryMap map[string]interface{}) {
 
 				case string:
 
-					//This is a simple string, so wrap the field and replace in the array
-					jsonValueType[itemKey] = fmt.Sprintf("%v.%v", dataWrapper, itemValue)
+					//if this is not "use_index", the wrap the string
+					if jsonKey != jsonQueryUseIndex {
+						//This is a simple string, so wrap the field and replace in the array
+						jsonValueType[itemKey] = fmt.Sprintf("%v.%v", dataWrapper, itemValue)
+					}
 
 				case []interface{}:
 

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

@@ -336,3 +336,33 @@ func TestQueryNoSelector(t *testing.T) {
 	testutil.AssertEquals(t, strings.Count(wrappedQuery, "\"selector\":{\"chaincodeid\":\"ns1\"}"), 1)
 
 }
+
+//TestQueryWithUseDesignDoc tests query with index design doc specified
+func TestQueryWithUseDesignDoc(t *testing.T) {
+
+	rawQuery := []byte(`{"selector":{"owner":{"$eq":"jerry"}},"use_index":"_design/testDoc","limit": 10,"skip": 0}`)
+
+	wrappedQuery, err := ApplyQueryWrapper("ns1", string(rawQuery))
+
+	//Make sure the query did not throw an exception
+	testutil.AssertNoError(t, err, "Unexpected error thrown when for query JSON")
+
+	//check to make sure the default selector is added
+	testutil.AssertEquals(t, strings.Count(wrappedQuery, "\"use_index\":\"_design/testDoc\""), 1)
+
+}
+
+//TestQueryWithUseDesignDocAndIndexName tests query with index design doc and index name specified
+func TestQueryWithUseDesignDocAndIndexName(t *testing.T) {
+
+	rawQuery := []byte(`{"selector":{"owner":{"$eq":"jerry"}},"use_index":["_design/testDoc","testIndexName"],"limit": 10,"skip": 0}`)
+
+	wrappedQuery, err := ApplyQueryWrapper("ns1", string(rawQuery))
+
+	//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, "\"use_index\":[\"_design/testDoc\",\"testIndexName\"]"), 1)
+
+}

devenv/Vagrantfile

@@ -20,6 +20,8 @@ LOCALDEV = "/local-dev"
 $script = <<SCRIPT
 set -x
 
+echo "127.0.0.1 couchdb" | tee -a /etc/hosts
+
 export DOCKER_STORAGE_BACKEND="#{ENV['DOCKER_STORAGE_BACKEND']}"
 
 cd #{SRCMOUNT}/devenv

examples/chaincode/go/marbles02/marbles_chaincode.go

@@ -29,11 +29,48 @@ under the License.
 
 // ==== Query marbles ====
 // peer chaincode query -C myc1 -n marbles -c '{"Args":["readMarble","marble1"]}'
+// peer chaincode query -C myc1 -n marbles -c '{"Args":["getHistoryForMarble","marble1"]}'
 
 // Rich Query (Only supported if CouchDB is used as state database):
 //   peer chaincode query -C myc1 -n marbles -c '{"Args":["queryMarblesByOwner","tom"]}'
 //   peer chaincode query -C myc1 -n marbles -c '{"Args":["queryMarbles","{\"selector\":{\"owner\":\"tom\"}}"]}'
 
+//The following examples demonstrate creating indexes on CouchDB
+//Example hostname:port configurations
+//
+//Docker or vagrant environments:
+// http://couchdb:5984/
+//
+//Inside couchdb docker container
+// http://127.0.0.1:5984/
+
+// Index for chaincodeid, docType, owner.
+// Note that docType and owner fields must be prefixed with the "data" wrapper
+// chaincodeid must be added for all queries
+//
+// Definition for use with Fauxton interface
+// {"index":{"fields":["chaincodeid","data.docType","data.owner"]},"ddoc":"indexOwnerDoc", "name":"indexOwner","type":"json"}
+//
+// example curl definition for use with command line
+// curl -i -X POST -H "Content-Type: application/json" -d "{\"index\":{\"fields\":[\"chaincodeid\",\"data.docType\",\"data.owner\"]},\"name\":\"indexOwner\",\"ddoc\":\"indexOwnerDoc\",\"type\":\"json\"}" http://hostname:port/myc1/_index
+//
+
+// Index for chaincodeid, docType, owner, size (descending order).
+// Note that docType, owner and size fields must be prefixed with the "data" wrapper
+// chaincodeid must be added for all queries
+//
+// Definition for use with Fauxton interface
+// {"index":{"fields":[{"data.size":"desc"},{"chaincodeid":"desc"},{"data.docType":"desc"},{"data.owner":"desc"}]},"ddoc":"indexSizeSortDoc", "name":"indexSizeSortDesc","type":"json"}
+//
+// example curl definition for use with command line
+// curl -i -X POST -H "Content-Type: application/json" -d "{\"index\":{\"fields\":[{\"data.size\":\"desc\"},{\"chaincodeid\":\"desc\"},{\"data.docType\":\"desc\"},{\"data.owner\":\"desc\"}]},\"ddoc\":\"indexSizeSortDoc\", \"name\":\"indexSizeSortDesc\",\"type\":\"json\"}" http://hostname:port/myc1/_index
+
+// Rich Query with index design doc and index name specified (Only supported if CouchDB is used as state database):
+//   peer chaincode query -C myc1 -n marbles -c '{"Args":["queryMarbles","{\"selector\":{\"docType\":\"marble\",\"owner\":\"tom\"}, \"use_index\":[\"_design/indexOwnerDoc\", \"indexOwner\"]}"]}'
+
+// Rich Query with index design doc specified only (Only supported if CouchDB is used as state database):
+//   peer chaincode query -C myc1 -n marbles -c '{"Args":["queryMarbles","{\"selector\":{\"docType\":{\"$eq\":\"marble\"},\"owner\":{\"$eq\":\"tom\"},\"size\":{\"$gt\":0}},\"fields\":[\"docType\",\"owner\",\"size\"],\"sort\":[{\"size\":\"desc\"}],\"use_index\":\"_design/indexSizeSortDoc\"}"]}'
+
 package main
 
 import (