Add RecordID to types.Document (#3495)

FerretDB · Oct 5, 2023 · 0a56f5b · 0a56f5b
1 parent f9f5e9a
commit 0a56f5b
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Showing 7 changed files with 59 additions and 7 deletions.
diff --git a/.github/settings.yml b/.github/settings.yml
@@ -12,6 +12,9 @@ repository:
 # https://docs.github.com/en/rest/issues/labels
 labels:
   # area
+  - name: area/admin
+    color: "#2931BF"
+    description: Issues about administration commands
   - name: area/aggregations
     color: "#5319E7"
     description: Issues about aggregation pipelines

diff --git a/internal/handlers/sjson/sjson.go b/internal/handlers/sjson/sjson.go
@@ -321,7 +321,7 @@ func unmarshalSingleValue(data json.RawMessage, sch *elem) (any, error) {
 	return fromSJSON(res), nil
 }
 
-// Marshal encodes the given document and set its schema in the field $s.
+// Marshal encodes given document fields and set its schema in the field $s.
 // Use it when you need to encode a document with schema, for example, when you want to store it in a database.
 func Marshal(d *types.Document) ([]byte, error) {
 	if d == nil {

diff --git a/internal/types/document.go b/internal/types/document.go
@@ -35,12 +35,18 @@ type document interface {
 
 // Document represents BSON document: an ordered collection of fields
 // (key/value pairs where key is a string and value is any BSON value).
+//
+// Data documents (that are stored in the backend) have a special RecordID property
+// that is not a field and can't be accessed by most methods.
+// It use used to locate the document in the backend.
 type Document struct {
-	fields []field
-	frozen bool
+	fields   []field
+	frozen   bool
+	recordID Timestamp
 }
 
 // field represents a field in the document.
+// RecordID is not a field.
 //
 // The order of field is like that to reduce a pressure on gc a bit, and make vet/fieldalignment linter happy.
 type field struct {
@@ -122,8 +128,20 @@ func NewDocument(pairs ...any) (*Document, error) {
 
 func (*Document) compositeType() {}
 
-// Freeze prevents document from further modifications.
-// Any methods that would modify the document will panic.
+// RecordID returns the document's RecordID (that is 0 by default).
+func (d *Document) RecordID() Timestamp {
+	return d.recordID
+}
+
+// SetRecordID sets the document's RecordID.
+func (d *Document) SetRecordID(recordID Timestamp) {
+	d.recordID = recordID
+}
+
+// Freeze prevents document from further field modifications.
+// Any methods that would modify document fields will panic.
+//
+// RecordID modification is not prevented.
 //
 // It is safe to call Freeze multiple times.
 func (d *Document) Freeze() {
@@ -140,6 +158,7 @@ func (d *Document) checkFrozen() {
 }
 
 // DeepCopy returns an unfrozen deep copy of this Document.
+// RecordID is copied too.
 func (d *Document) DeepCopy() *Document {
 	if d == nil {
 		panic("types.Document.DeepCopy: nil document")

diff --git a/internal/types/object_id.go b/internal/types/object_id.go
@@ -34,7 +34,7 @@ const ObjectIDLen = 12
 
 // NewObjectID returns a new ObjectID.
 func NewObjectID() ObjectID {
-	return newObjectIDTime(time.Now())
+	return newObjectIDTime(time.Now()) // https://github.com/FerretDB/FerretDB/issues/3486
 }
 
 // newObjectIDTime returns a new ObjectID with given time.

diff --git a/internal/types/timestamp.go b/internal/types/timestamp.go
@@ -30,6 +30,11 @@ func NewTimestamp(t time.Time, c uint32) Timestamp {
 	return Timestamp((uint64(t.Unix()) << 32) | uint64(c))
 }
 
+// NewTimestampSigned returns the timestamp for the given signed value.
+func NewTimestampSigned(i int64) Timestamp {
+	return Timestamp(i)
+}
+
 // NextTimestamp returns the next timestamp for the given time value.
 func NextTimestamp(t time.Time) Timestamp {
 	// Technically, that should be a counter within a second, not a process-wide,
@@ -44,3 +49,8 @@ func (ts Timestamp) Time() time.Time {
 	sec := int64(ts >> 32)
 	return time.Unix(sec, 0).UTC()
 }
+
+// Signed returns the timestamp as a signed value.
+func (ts Timestamp) Signed() int64 {
+	return int64(ts)
+}
diff --git a/internal/types/timestamp_test.go b/internal/types/timestamp_test.go
@@ -43,3 +43,22 @@ func TestNextTimestamp(t *testing.T) {
 		assert.Equal(t, d, NextTimestamp(d).Time())
 	})
 }
+
+func TestNewTimestampSigned(t *testing.T) {
+	// one second before Y2K38
+	now := time.Date(2038, time.January, 19, 3, 14, 6, 0, time.UTC)
+
+	ts1 := NextTimestamp(now)
+	ts2 := NextTimestamp(now.Add(time.Second))
+	ts3 := NextTimestamp(now.Add(2 * time.Second))
+
+	assert.Less(t, ts1, ts2)
+	assert.Less(t, ts2, ts3)
+
+	assert.Less(t, ts1.Signed(), ts2.Signed())
+	assert.Greater(t, ts2.Signed(), ts3.Signed(), "expected Epochalypse")
+
+	assert.Equal(t, ts1, NewTimestampSigned(ts1.Signed()))
+	assert.Equal(t, ts2, NewTimestampSigned(ts2.Signed()))
+	assert.Equal(t, ts3, NewTimestampSigned(ts3.Signed()))
+}
diff --git a/internal/types/types.go b/internal/types/types.go
@@ -137,7 +137,8 @@ func deepCopy(value any) any {
 		}
 
 		return &Document{
-			fields: fields,
+			fields:   fields,
+			recordID: value.recordID,
 		}
 
 	case *Array: