Add createTime to Document.

packages/firestore/src/model/document.ts

@@ -101,6 +101,13 @@ export interface Document {
    */
   readonly readTime: SnapshotVersion;
 
+  /**
+   * The timestamp at which the document was created. This value increases
+   * monotonically when a document is deleted then recreated. It can also be
+   * compared to `createTime` of other documents and the `readTime` of a query.
+   */
+  readonly createTime: SnapshotVersion;
+
   /** The underlying data of this document or an empty value if no data exists. */
   readonly data: ObjectValue;
 
@@ -163,6 +170,7 @@ export class MutableDocument implements Document {
     private documentType: DocumentType,
     public version: SnapshotVersion,
     public readTime: SnapshotVersion,
+    public createTime: SnapshotVersion,
     public data: ObjectValue,
     private documentState: DocumentState
   ) {}
@@ -175,8 +183,9 @@ export class MutableDocument implements Document {
     return new MutableDocument(
       documentKey,
       DocumentType.INVALID,
-      SnapshotVersion.min(),
-      SnapshotVersion.min(),
+      /* version */ SnapshotVersion.min(),
+      /* readTime */ SnapshotVersion.min(),
+      /* createTime */ SnapshotVersion.min(),
       ObjectValue.empty(),
       DocumentState.SYNCED
     );
@@ -189,13 +198,15 @@ export class MutableDocument implements Document {
   static newFoundDocument(
     documentKey: DocumentKey,
     version: SnapshotVersion,
+    createTime: SnapshotVersion,
     value: ObjectValue
   ): MutableDocument {
     return new MutableDocument(
       documentKey,
       DocumentType.FOUND_DOCUMENT,
-      version,
-      SnapshotVersion.min(),
+      /* version */ version,
+      /* readTime */ SnapshotVersion.min(),
+      /* createTime */ createTime,
       value,
       DocumentState.SYNCED
     );
@@ -209,8 +220,9 @@ export class MutableDocument implements Document {
     return new MutableDocument(
       documentKey,
       DocumentType.NO_DOCUMENT,
-      version,
-      SnapshotVersion.min(),
+      /* version */ version,
+      /* readTime */ SnapshotVersion.min(),
+      /* createTime */ SnapshotVersion.min(),
       ObjectValue.empty(),
       DocumentState.SYNCED
     );
@@ -228,8 +240,9 @@ export class MutableDocument implements Document {
     return new MutableDocument(
       documentKey,
       DocumentType.UNKNOWN_DOCUMENT,
-      version,
-      SnapshotVersion.min(),
+      /* version */ version,
+      /* readTime */ SnapshotVersion.min(),
+      /* createTime */ SnapshotVersion.min(),
       ObjectValue.empty(),
       DocumentState.HAS_COMMITTED_MUTATIONS
     );
@@ -340,6 +353,7 @@ export class MutableDocument implements Document {
       this.documentType,
       this.version,
       this.readTime,
+      this.createTime,
       this.data.clone(),
       this.documentState
     );

packages/firestore/src/remote/serializer.ts

@@ -395,7 +395,8 @@ export function toDocument(
   return {
     name: toName(serializer, document.key),
     fields: document.data.value.mapValue.fields,
-    updateTime: toTimestamp(serializer, document.version.toTimestamp())
+    updateTime: toTimestamp(serializer, document.version.toTimestamp()),
+    createTime: toTimestamp(serializer, document.createTime.toTimestamp())
   };
 }
 
@@ -406,8 +407,16 @@ export function fromDocument(
 ): MutableDocument {
   const key = fromName(serializer, document.name!);
   const version = fromVersion(document.updateTime!);
+  const createTime = document.createTime
+    ? fromVersion(document.createTime)
+    : SnapshotVersion.min();
   const data = new ObjectValue({ mapValue: { fields: document.fields } });
-  const result = MutableDocument.newFoundDocument(key, version, data);
+  const result = MutableDocument.newFoundDocument(
+    key,
+    version,
+    createTime,
+    data
+  );
   if (hasCommittedMutations) {
     result.setHasCommittedMutations();
   }
@@ -426,8 +435,11 @@ function fromFound(
   assertPresent(doc.found.updateTime, 'doc.found.updateTime');
   const key = fromName(serializer, doc.found.name);
   const version = fromVersion(doc.found.updateTime);
+  const createTime = doc.found.createTime
+    ? fromVersion(doc.found.createTime)
+    : SnapshotVersion.min();
   const data = new ObjectValue({ mapValue: { fields: doc.found.fields } });
-  return MutableDocument.newFoundDocument(key, version, data);
+  return MutableDocument.newFoundDocument(key, version, createTime, data);
 }
 
 function fromMissing(
@@ -493,10 +505,18 @@ export function fromWatchChange(
     );
     const key = fromName(serializer, entityChange.document.name);
     const version = fromVersion(entityChange.document.updateTime);
+    const createTime = entityChange.document.createTime
+      ? fromVersion(entityChange.document.createTime)
+      : SnapshotVersion.min();
     const data = new ObjectValue({
       mapValue: { fields: entityChange.document.fields }
     });
-    const doc = MutableDocument.newFoundDocument(key, version, data);
+    const doc = MutableDocument.newFoundDocument(
+      key,
+      version,
+      createTime,
+      data
+    );
     const updatedTargetIds = entityChange.targetIds || [];
     const removedTargetIds = entityChange.removedTargetIds || [];
     watchChange = new DocumentWatchChange(

packages/firestore/test/unit/local/local_store.test.ts

@@ -1958,6 +1958,33 @@ function genericLocalStoreTests(
       .finish();
   });
 
+  it('handles document creation time', () => {
+    return (
+      expectLocalStore()
+        .afterAllocatingQuery(query('col'))
+        .toReturnTargetId(2)
+        .after(docAddedRemoteEvent(doc('col/doc1', 12, { foo: 'bar' }, 5), [2]))
+        .toReturnChanged(doc('col/doc1', 12, { foo: 'bar' }, 5))
+        .toContain(doc('col/doc1', 12, { foo: 'bar' }, 5))
+        .after(setMutation('col/doc1', { foo: 'newBar' }))
+        .toReturnChanged(
+          doc('col/doc1', 12, { foo: 'newBar' }, 5).setHasLocalMutations()
+        )
+        .toContain(
+          doc('col/doc1', 12, { foo: 'newBar' }, 5).setHasLocalMutations()
+        )
+        .afterAcknowledgingMutation({ documentVersion: 13 })
+        // We haven't seen the remote event yet
+        .toReturnChanged(
+          doc('col/doc1', 13, { foo: 'newBar' }, 5).setHasCommittedMutations()
+        )
+        .toContain(
+          doc('col/doc1', 13, { foo: 'newBar' }, 5).setHasCommittedMutations()
+        )
+        .finish()
+    );
+  });
+
   it('uses target mapping to execute queries', () => {
     if (gcIsEager) {
       return;

packages/firestore/test/unit/remote/serializer.helper.ts

@@ -799,11 +799,12 @@ export function serializerTest(
     });
 
     it('toDocument() / fromDocument', () => {
-      const d = doc('foo/bar', 42, { a: 5, b: 'b' });
+      const d = doc('foo/bar', 42, { a: 5, b: 'b' }, /* createTime */ 12);
       const proto = {
         name: toName(s, d.key),
         fields: d.data.value.mapValue.fields,
-        updateTime: toVersion(s, d.version)
+        updateTime: toVersion(s, d.version),
+        createTime: toVersion(s, d.createTime)
       };
       const serialized = toDocument(s, d);
       expect(serialized).to.deep.equal(proto);

packages/firestore/test/util/helpers.ts

@@ -155,11 +155,13 @@ export function ref(key: string, offset?: number): DocumentReference {
 export function doc(
   keyStr: string,
   ver: TestSnapshotVersion,
-  jsonOrObjectValue: JsonObject<unknown> | ObjectValue
+  jsonOrObjectValue: JsonObject<unknown> | ObjectValue,
+  createTime?: TestSnapshotVersion
 ): MutableDocument {
   return MutableDocument.newFoundDocument(
     key(keyStr),
     version(ver),
+    createTime ? version(createTime) : SnapshotVersion.min(),
     jsonOrObjectValue instanceof ObjectValue
       ? jsonOrObjectValue
       : wrapObject(jsonOrObjectValue)