[FAB-8336] Add create or update msg for CouchDB index

Problem Statement:

If the provided index definitions have more than one (lets say N)
index with same DesignDoc and indexName but with potentially different indexes,
the log will contain N messages like `created CouchDB index in the channel...`
but in reality only 1 index will be created in CouchDB. Fabric goes through
each file in alphabetic order, creating and (quietly) replacing the index
created in last round with the same DDoc and indexName, so only the last index
remains in CouchDB.

Solution:

Part of the confusion can be prevented by updating the message when an index
is created or updated in CouchDB.  The create index command responds with
metadata that can be captured and provide a more detailed message and can
determine if the index has been created or updated.  This can be accomplished
with the existing http request.

Change-Id: I84674ceed54dadba9470d768a028a6acb3b237f6
Signed-off-by: Chris Elder <chris.elder@us.ibm.com>

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

@@ -130,7 +130,7 @@ func (vdb *VersionedDB) HandleChaincodeDeploy(chaincodeDefinition *cceventmgmt.C
 					return nil
 				}
 				//create the index from the tar entry
-				if err := db.CreateIndex(string(indexData)); err != nil {
+				if _, err := db.CreateIndex(string(indexData)); err != nil {
 					logger.Errorf("Error during creation of index from file=[%s] for chaincode=[%s] on chain=[%s]. Error=%s",
 						tarHeader.Name, chaincodeDefinition, vdb.chainName, err)
 				}

core/ledger/util/couchdb/couchdb.go

@@ -156,6 +156,13 @@ type DBReturn struct {
 	Reason     string `json:"reason"`
 }
 
+//CreateIndexResponse contains an the index creation response from CouchDB
+type CreateIndexResponse struct {
+	Result string `json:"result"`
+	ID     string `json:"id"`
+	Name   string `json:"name"`
+}
+
 //AttachmentInfo contains the definition for an attached file for couchdb
 type AttachmentInfo struct {
 	Name            string
@@ -1134,19 +1141,19 @@ func (dbclient *CouchDatabase) ListIndex() (*[]IndexResult, error) {
 }
 
 // CreateIndex method provides a function creating an index
-func (dbclient *CouchDatabase) CreateIndex(indexdefinition string) error {
+func (dbclient *CouchDatabase) CreateIndex(indexdefinition string) (*CreateIndexResponse, error) {
 
 	logger.Debugf("Entering CreateIndex()  indexdefinition=%s", indexdefinition)
 
 	//Test to see if this is a valid JSON
 	if IsJSON(indexdefinition) != true {
-		return fmt.Errorf("JSON format is not valid")
+		return nil, fmt.Errorf("JSON format is not valid")
 	}
 
 	indexURL, err := url.Parse(dbclient.CouchInstance.conf.URL)
 	if err != nil {
 		logger.Errorf("URL parse error: %s", err.Error())
-		return err
+		return nil, err
 	}
 
 	indexURL.Path = dbclient.DBName + "/_index"
@@ -1156,14 +1163,41 @@ func (dbclient *CouchDatabase) CreateIndex(indexdefinition string) error {
 
 	resp, _, err := dbclient.CouchInstance.handleRequest(http.MethodPost, indexURL.String(), []byte(indexdefinition), "", "", maxRetries, true)
 	if err != nil {
-		return err
+		return nil, err
 	}
 	defer closeResponseBody(resp)
 
-	logger.Infof("Created CouchDB index in state database %s", dbclient.DBName)
+	if resp == nil {
+		return nil, fmt.Errorf("An invalid response was received from CouchDB")
+	}
 
-	return nil
+	//Read the response body
+	respBody, err := ioutil.ReadAll(resp.Body)
+	if err != nil {
+		return nil, err
+	}
+
+	couchDBReturn := &CreateIndexResponse{}
+
+	jsonBytes := []byte(respBody)
+
+	//unmarshal the response
+	err = json.Unmarshal(jsonBytes, &couchDBReturn)
+	if err != nil {
+		return nil, err
+	}
+
+	if couchDBReturn.Result == "created" {
+
+		logger.Infof("Created CouchDB index [%s] in state database [%s] using design document [%s]", couchDBReturn.Name, dbclient.DBName, couchDBReturn.ID)
+
+		return couchDBReturn, nil
+
+	}
+
+	logger.Infof("Updated CouchDB index [%s] in state database [%s] using design document [%s]", couchDBReturn.Name, dbclient.DBName, couchDBReturn.ID)
 
+	return couchDBReturn, nil
 }
 
 // DeleteIndex method provides a function deleting an index

core/ledger/util/couchdb/couchdb_test.go

@@ -216,7 +216,7 @@ func TestBadCouchDBInstance(t *testing.T) {
 	testutil.AssertError(t, err, "Error should have been thrown with ListIndex and invalid connection")
 
 	//Test CreateIndex with bad connection
-	err = badDB.CreateIndex("")
+	_, err = badDB.CreateIndex("")
 	testutil.AssertError(t, err, "Error should have been thrown with CreateIndex and invalid connection")
 
 	//Test DeleteIndex with bad connection
@@ -964,7 +964,7 @@ func TestIndexOperations(t *testing.T) {
 	indexDefSize := "{\"index\":{\"fields\":[{\"size\":\"desc\"}]},\"ddoc\":\"indexSizeSortDoc\", \"name\":\"indexSizeSortName\",\"type\":\"json\"}"
 
 	//Create the index
-	err = db.CreateIndex(indexDefSize)
+	_, err = db.CreateIndex(indexDefSize)
 	testutil.AssertNoError(t, err, fmt.Sprintf("Error thrown while creating an index"))
 
 	//Retrieve the list of indexes
@@ -988,7 +988,7 @@ func TestIndexOperations(t *testing.T) {
 	indexDefColor := "{\"index\":{\"fields\":[{\"color\":\"desc\"}]}}"
 
 	//Create the index
-	err = db.CreateIndex(indexDefColor)
+	_, err = db.CreateIndex(indexDefColor)
 	testutil.AssertNoError(t, err, fmt.Sprintf("Error thrown while creating an index"))
 
 	//Retrieve the list of indexes
@@ -1034,7 +1034,7 @@ func TestIndexOperations(t *testing.T) {
 	testutil.AssertError(t, err, fmt.Sprintf("Error thrown while querying without a valid index"))
 
 	//Create the index
-	err = db.CreateIndex(indexDefSize)
+	_, err = db.CreateIndex(indexDefSize)
 	testutil.AssertNoError(t, err, fmt.Sprintf("Error thrown while creating an index"))
 
 	//Delay for 100ms since CouchDB index list is updated async after index create/drop
@@ -1048,9 +1048,22 @@ func TestIndexOperations(t *testing.T) {
 	indexDefSize = "{\"index\":{\"fields\":[{\"data.size\":\"desc\"},{\"data.owner\":\"desc\"}]},\"ddoc\":\"indexSizeOwnerSortDoc\", \"name\":\"indexSizeOwnerSortName\",\"type\":\"json\"}"
 
 	//Create the index
-	err = db.CreateIndex(indexDefSize)
+	dbResp, err := db.CreateIndex(indexDefSize)
 	testutil.AssertNoError(t, err, fmt.Sprintf("Error thrown while creating an index"))
 
+	//verify the response is "created" for an index creation
+	testutil.AssertEquals(t, dbResp.Result, "created")
+
+	//Delay for 100ms since CouchDB index list is updated async after index create/drop
+	time.Sleep(100 * time.Millisecond)
+
+	//Update the index
+	dbResp, err = db.CreateIndex(indexDefSize)
+	testutil.AssertNoError(t, err, fmt.Sprintf("Error thrown while creating an index"))
+
+	//verify the response is "exists" for an update
+	testutil.AssertEquals(t, dbResp.Result, "exists")
+
 	//Retrieve the list of indexes
 	//Delay for 100ms since CouchDB index list is updated async after index create/drop
 	time.Sleep(100 * time.Millisecond)
@@ -1064,14 +1077,14 @@ func TestIndexOperations(t *testing.T) {
 	indexDefSize = "{\"index\"{\"fields\":[{\"data.size\":\"desc\"},{\"data.owner\":\"desc\"}]},\"ddoc\":\"indexSizeOwnerSortDoc\", \"name\":\"indexSizeOwnerSortName\",\"type\":\"json\"}"
 
 	//Create the index
-	err = db.CreateIndex(indexDefSize)
+	_, err = db.CreateIndex(indexDefSize)
 	testutil.AssertError(t, err, fmt.Sprintf("Error should have been thrown for an invalid index JSON"))
 
 	//Create an invalid index definition with a valid JSON and an invalid index definition
 	indexDefSize = "{\"index\":{\"fields2\":[{\"data.size\":\"desc\"},{\"data.owner\":\"desc\"}]},\"ddoc\":\"indexSizeOwnerSortDoc\", \"name\":\"indexSizeOwnerSortName\",\"type\":\"json\"}"
 
 	//Create the index
-	err = db.CreateIndex(indexDefSize)
+	_, err = db.CreateIndex(indexDefSize)
 	testutil.AssertError(t, err, fmt.Sprintf("Error should have been thrown for an invalid index definition"))
 
 }