ADBDEV-2901 Fix order of restoring metadata (#23)

Initially, gpbackup created consistent copies of databases, ordering
all object by oid, which created a correct sequence of objects. But in
ADBDEV-1973 (#9) the backup order was changed and the objects started to be
sorted by their size, which broke the logic of backup process. This
patch restores ordering by oid, but doesn't break order based on relation
size, because gpbackup stores two different lists of metadata and data
objects. This patch reorders metadata only, so all objects can be correclty
restored, but doesn't alter data objects order, so the data can be recovered
in any desired way.

backup/backup.go

@@ -226,10 +226,10 @@ func backupPredata(metadataFile *utils.FileWithByteCount, tables []Table, tableO
 	objects := make([]Sortable, 0)
 	metadataMap := make(MetadataMap)
 
+	objects = append(objects, convertToSortableSlice(tables)...)
 	if !tableOnly {
 		functions, funcInfoMap = retrieveFunctions(&objects, metadataMap)
 	}
-	objects = append(objects, convertToSortableSlice(tables)...)
 	relationMetadata := GetMetadataForObjectType(connectionPool, TYPE_RELATION)
 	addToMetadataMap(relationMetadata, metadataMap)
 

backup/dependencies.go

@@ -2,6 +2,7 @@ package backup
 
 import (
 	"fmt"
+	"sort"
 	"strings"
 
 	"github.com/greenplum-db/gp-common-go-libs/dbconn"
@@ -85,6 +86,24 @@ type Sortable interface {
 	GetUniqueID() UniqueID
 }
 
+type Sortables []Sortable
+
+func (s Sortables) Len() int {
+	return len(s)
+}
+func (s Sortables) Swap(i, j int) {
+	s[i], s[j] = s[j], s[i]
+}
+func (s Sortables) Less(i, j int) bool {
+	return s[i].GetUniqueID().Oid < s[j].GetUniqueID().Oid
+}
+
+func SortByOid(sortables []Sortable) []Sortable {
+	s := Sortables(sortables)
+	sort.Sort(s)
+	return []Sortable(s)
+}
+
 func TopologicalSort(slice []Sortable, dependencies DependencyMap) []Sortable {
 	inDegrees := make(map[UniqueID]int)
 	dependencyIndexes := make(map[UniqueID]int)

backup/wrappers.go

@@ -566,6 +566,7 @@ func backupDependentObjects(metadataFile *utils.FileWithByteCount, tables []Tabl
 
 	gplog.Verbose("Writing CREATE statements for dependent objects to metadata file")
 
+	sortables = SortByOid(sortables)
 	backupSet := createBackupSet(sortables)
 	relevantDeps := GetDependencies(connectionPool, backupSet)
 	if connectionPool.Version.Is("4") && !tableOnly {

end_to_end/end_to_end_suite_test.go

@@ -1445,6 +1445,31 @@ var _ = Describe("backup and restore end to end tests", func() {
 
 				assertArtifactsCleaned(restoreConn, timestamp)
 			})
+			It("runs gpbackup and gprestore to backup functions depending on table row's type", func() {
+				skipIfOldBackupVersionBefore("1.19.0")
+
+				testhelper.AssertQueryRuns(backupConn, "CREATE TABLE table_provides_type (n int);")
+				defer testhelper.AssertQueryRuns(backupConn, "DROP TABLE table_provides_type;")
+
+				testhelper.AssertQueryRuns(backupConn, "INSERT INTO table_provides_type values (1);")
+				testhelper.AssertQueryRuns(backupConn, "CREATE OR REPLACE FUNCTION func_depends_on_row_type(arg table_provides_type[]) RETURNS void AS $$ BEGIN; SELECT NULL; END; $$ LANGUAGE SQL;")
+
+				defer testhelper.AssertQueryRuns(backupConn, "DROP FUNCTION func_depends_on_row_type(arg table_provides_type[]);")
+
+				timestamp := gpbackup(gpbackupPath, backupHelperPath)
+				gprestore(gprestorePath, restoreHelperPath, timestamp,
+					"--redirect-db", "restoredb")
+
+				assertRelationsCreated(restoreConn, TOTAL_RELATIONS+1) // for 1 new table
+				assertDataRestored(restoreConn, schema2TupleCounts)
+				assertDataRestored(restoreConn, map[string]int{
+					"public.foo":                 40000,
+					"public.holds":               50000,
+					"public.sales":               13,
+					"public.table_provides_type": 1})
+
+				assertArtifactsCleaned(restoreConn, timestamp)
+			})
 			It("Can restore xml with xmloption set to document", func() {
 				testutils.SkipIfBefore6(backupConn)
 				// Set up the XML table that contains XML content