Fallback to LMT on missing source hash

cmd/syncComparator.go

@@ -28,14 +28,15 @@ import (
 )
 
 const (
-	syncSkipReasonTime                       = "the source has an older LMT than the destination"
-	syncSkipReasonMissingHash                = "the source lacks an associated hash; please upload with --put-md5"
-	syncSkipReasonSameHash                   = "the source has the same hash"
-	syncOverwriteReasonNewerHash             = "the source has a differing hash"
-	syncOverwriteReasonNewerLMT              = "the source is more recent than the destination"
-	syncStatusSkipped                        = "skipped"
-	syncStatusOverwritten                    = "overwritten"
-	syncOverwriteReasonDeleteDestinationFile = "the flag delete-destination-file is set to true"
+	syncSkipReasonTime                        = "the source has an older LMT than the destination"
+	syncSkipReasonTimeAndMissingHash          = "the source lacks an associated hash (please upload with --put-md5 for hash comparison) and has an older LMT than the destination"
+	syncSkipReasonMissingHash                 = "the source lacks an associated hash; please upload with --put-md5"
+	syncSkipReasonSameHash                    = "the source has the same hash"
+	syncOverwriteReasonNewerHash              = "the source has a differing hash"
+	syncOverwriteReasonNewerLMT               = "the source is more recent than the destination"
+	syncOverwriteReasonNewerLMTAndMissingHash = "the source lacks an associated hash (please upload with --put-md5 for hash comparison) and is more recent than the destination"
+	syncStatusSkipped                         = "skipped"
+	syncStatusOverwritten                     = "overwritten"
 )
 
 func syncComparatorLog(fileName, status, skipReason string, stdout bool) {
@@ -98,8 +99,14 @@ func (f *syncDestinationComparator) processIfNecessary(destinationObject StoredO
 			switch f.comparisonHashType {
 			case common.ESyncHashType.MD5():
 				if sourceObjectInMap.md5 == nil {
-					syncComparatorLog(sourceObjectInMap.relativePath, syncStatusSkipped, syncSkipReasonMissingHash, true)
-					return nil
+					if sourceObjectInMap.isMoreRecentThan(destinationObject, f.preferSMBTime) {
+						syncComparatorLog(sourceObjectInMap.relativePath, syncStatusOverwritten, syncOverwriteReasonNewerLMTAndMissingHash, false)
+						return f.copyTransferScheduler(sourceObjectInMap)
+					} else {
+						// skip if dest is more recent
+						syncComparatorLog(sourceObjectInMap.relativePath, syncStatusSkipped, syncSkipReasonTimeAndMissingHash, false)
+						return nil
+					}
 				}
 
 				if !reflect.DeepEqual(sourceObjectInMap.md5, destinationObject.md5) {
@@ -177,8 +184,14 @@ func (f *syncSourceComparator) processIfNecessary(sourceObject StoredObject) err
 			switch f.comparisonHashType {
 			case common.ESyncHashType.MD5():
 				if sourceObject.md5 == nil {
-					syncComparatorLog(sourceObject.relativePath, syncStatusSkipped, syncSkipReasonMissingHash, true)
-					return nil
+					if sourceObject.isMoreRecentThan(destinationObjectInMap, f.preferSMBTime) {
+						syncComparatorLog(sourceObject.relativePath, syncStatusOverwritten, syncOverwriteReasonNewerLMTAndMissingHash, false)
+						return f.copyTransferScheduler(sourceObject)
+					} else {
+						// skip if dest is more recent
+						syncComparatorLog(sourceObject.relativePath, syncStatusSkipped, syncSkipReasonTimeAndMissingHash, false)
+						return nil
+					}
 				}
 
 				if !reflect.DeepEqual(sourceObject.md5, destinationObjectInMap.md5) {

e2etest/zt_newe2e_sync_test.go

@@ -261,3 +261,178 @@ func (s *SyncTestSuite) Scenario_TestSyncDeleteDestinationIfNecessary(svm *Scena
 		},
 	}, true)
 }
+
+// Note : For local sources, the hash is computed by a hashProcessor created in zc_traverser_local, so there is no way
+// for local sources to have no source hash. As such these tests only cover remote sources.
+func (s *SyncTestSuite) Scenario_TestSyncHashTypeSourceHash(svm *ScenarioVariationManager) {
+
+	// There are 4 cases to consider, this test will cover all of them
+	// 1. Has hash and is equal -> skip
+	// 2. Has hash and is not equal -> overwrite
+	// 3. Has no hash and src LMT after dest LMT -> overwrite
+	// 4. Has no hash and src LMT before dest LMT -> skip
+
+	// Create dest
+	hashEqualBody := NewRandomObjectContentContainer(512)
+	hashNotEqualBody := NewRandomObjectContentContainer(512)
+	noHashDestSrc := NewRandomObjectContentContainer(512)
+	noHashSrcDest := NewRandomObjectContentContainer(512)
+
+	zeroBody := NewZeroObjectContentContainer(512)
+
+	dest := CreateResource[ContainerResourceManager](svm,
+		GetRootResource(svm, ResolveVariation(svm, []common.Location{common.ELocation.Blob(), common.ELocation.Local()})),
+		ResourceDefinitionContainer{
+			Objects: ObjectResourceMappingFlat{
+				"hashequal":     ResourceDefinitionObject{Body: hashEqualBody},
+				"hashnotequal":  ResourceDefinitionObject{Body: zeroBody},
+				"nohashdestsrc": ResourceDefinitionObject{Body: noHashDestSrc},
+				"nohashsrcdest": ResourceDefinitionObject{Body: zeroBody},
+			},
+		},
+	)
+
+	time.Sleep(time.Second * 10) // Make sure source is newer
+
+	srcObjs := ObjectResourceMappingFlat{
+		"hashequal":     ResourceDefinitionObject{Body: hashEqualBody},
+		"hashnotequal":  ResourceDefinitionObject{Body: hashNotEqualBody},
+		"nohashdestsrc": ResourceDefinitionObject{Body: noHashDestSrc},
+		"nohashsrcdest": ResourceDefinitionObject{Body: noHashSrcDest},
+	}
+
+	src := CreateResource[ContainerResourceManager](svm,
+		GetRootResource(svm, common.ELocation.Blob()),
+		ResourceDefinitionContainer{
+			Objects: srcObjs,
+		},
+	)
+
+	// Need to manually unset the md5
+	src.GetObject(svm, "nohashdestsrc", common.EEntityType.File()).SetHTTPHeaders(svm, contentHeaders{contentMD5: nil})
+	src.GetObject(svm, "nohashsrcdest", common.EEntityType.File()).SetHTTPHeaders(svm, contentHeaders{contentMD5: nil})
+
+	time.Sleep(time.Second * 10) // Make sure destination is newer
+
+	// Re-create nohashsrcdest so the src LMT is before dest LMT
+	dest.GetObject(svm, "nohashsrcdest", common.EEntityType.File()).Create(svm, noHashSrcDest, ObjectProperties{})
+
+	stdOut, _ := RunAzCopy(
+		svm,
+		AzCopyCommand{
+			Verb:    AzCopyVerbSync,
+			Targets: []ResourceManager{src, dest},
+			Flags: SyncFlags{
+				CopySyncCommonFlags: CopySyncCommonFlags{
+					Recursive: pointerTo(true),
+				},
+				CompareHash: pointerTo(common.ESyncHashType.MD5()),
+			},
+		})
+
+	// All source, dest should match
+	ValidateResource[ContainerResourceManager](svm, dest, ResourceDefinitionContainer{
+		Objects: srcObjs,
+	}, true)
+
+	// Only non skipped paths should be in plan file
+	ValidatePlanFiles(svm, stdOut, ExpectedPlanFile{
+		Objects: map[PlanFilePath]PlanFileObject{
+			PlanFilePath{SrcPath: "/hashnotequal", DstPath: "/hashnotequal"}: {
+				Properties: ObjectProperties{},
+			},
+			PlanFilePath{SrcPath: "/nohashdestsrc", DstPath: "/nohashdestsrc"}: {
+				Properties: ObjectProperties{},
+			},
+		},
+	})
+}
+
+// Note : For local destinations, the hash is computed by a hashProcessor created in zc_traverser_local, so there is no way
+// for local destinations to have no source hash. As such these tests only cover remote destinations.
+func (s *SyncTestSuite) Scenario_TestSyncHashTypeDestinationHash(svm *ScenarioVariationManager) {
+
+	// There are 4 cases to consider, this test will cover all of them
+	// 1. Has hash and is equal -> skip
+	// 2. Has hash and is not equal -> overwrite
+	// 3. Has no hash and src LMT after dest LMT -> overwrite
+	// 4. Has no hash and src LMT before dest LMT -> overwrite
+
+	// Create dest
+	hashEqualBody := NewRandomObjectContentContainer(512)
+	hashNotEqualBody := NewRandomObjectContentContainer(512)
+	noHashDestSrc := NewRandomObjectContentContainer(512)
+	noHashSrcDest := NewRandomObjectContentContainer(512)
+
+	zeroBody := NewZeroObjectContentContainer(512)
+
+	dest := CreateResource[ContainerResourceManager](svm,
+		GetRootResource(svm, common.ELocation.Blob()),
+		ResourceDefinitionContainer{
+			Objects: ObjectResourceMappingFlat{
+				"hashequal":     ResourceDefinitionObject{Body: hashEqualBody},
+				"hashnotequal":  ResourceDefinitionObject{Body: zeroBody},
+				"nohashdestsrc": ResourceDefinitionObject{Body: zeroBody},
+				"nohashsrcdest": ResourceDefinitionObject{Body: zeroBody},
+			},
+		},
+	)
+
+	time.Sleep(time.Second * 10) // Make sure source is newer
+
+	srcObjs := ObjectResourceMappingFlat{
+		"hashequal":     ResourceDefinitionObject{Body: hashEqualBody},
+		"hashnotequal":  ResourceDefinitionObject{Body: hashNotEqualBody},
+		"nohashdestsrc": ResourceDefinitionObject{Body: noHashDestSrc},
+		"nohashsrcdest": ResourceDefinitionObject{Body: noHashSrcDest},
+	}
+
+	src := CreateResource[ContainerResourceManager](svm,
+		GetRootResource(svm, ResolveVariation(svm, []common.Location{common.ELocation.Blob(), common.ELocation.Local()})),
+		ResourceDefinitionContainer{
+			Objects: srcObjs,
+		},
+	)
+
+	// Need to manually unset the md5
+	dest.GetObject(svm, "nohashdestsrc", common.EEntityType.File()).SetHTTPHeaders(svm, contentHeaders{contentMD5: nil})
+	dest.GetObject(svm, "nohashsrcdest", common.EEntityType.File()).SetHTTPHeaders(svm, contentHeaders{contentMD5: nil})
+
+	time.Sleep(time.Second * 10) // Make sure destination is newer
+
+	// Re-create nohashsrcdest so the src LMT is before dest LMT
+	dest.GetObject(svm, "nohashsrcdest", common.EEntityType.File()).Create(svm, zeroBody, ObjectProperties{})
+
+	stdOut, _ := RunAzCopy(
+		svm,
+		AzCopyCommand{
+			Verb:    AzCopyVerbSync,
+			Targets: []ResourceManager{src, dest},
+			Flags: SyncFlags{
+				CopySyncCommonFlags: CopySyncCommonFlags{
+					Recursive: pointerTo(true),
+				},
+				CompareHash: pointerTo(common.ESyncHashType.MD5()),
+			},
+		})
+
+	// All source, dest should match
+	ValidateResource[ContainerResourceManager](svm, dest, ResourceDefinitionContainer{
+		Objects: srcObjs,
+	}, true)
+
+	// Only non skipped paths should be in plan file
+	ValidatePlanFiles(svm, stdOut, ExpectedPlanFile{
+		Objects: map[PlanFilePath]PlanFileObject{
+			PlanFilePath{SrcPath: "/hashnotequal", DstPath: "/hashnotequal"}: {
+				Properties: ObjectProperties{},
+			},
+			PlanFilePath{SrcPath: "/nohashdestsrc", DstPath: "/nohashdestsrc"}: {
+				Properties: ObjectProperties{},
+			},
+			PlanFilePath{SrcPath: "/nohashsrcdest", DstPath: "/nohashsrcdest"}: {
+				Properties: ObjectProperties{},
+			},
+		},
+	})
+}