feat(loki): add option to disable meta property for documents added t…

…o a collection

See techfort/LokiJS@d031e47

packages/loki/spec/generic/persistence.spec.ts

@@ -59,6 +59,19 @@ describe("testing unique index serialization", () => {
   });
 });
 
+describe("testing disable meta serialization", function () {
+  it("should have meta disabled", function () {
+    const db = new Loki();
+    db.addCollection<User>("users", { disableMeta: true });
+
+    const ser = db.serialize();
+    const reloaded = new Loki();
+    reloaded.loadJSON(ser);
+    const coll = reloaded.getCollection("users");
+    expect(coll["disableMeta"]).toEqual(true);
+  });
+});
+
 describe("testing destructured serialization/deserialization", () => {
   it("verify default (D) destructuring works as expected", () => {
     const ddb = new Loki("test.db", {serializationMethod: "destructured"});

packages/loki/spec/generic/test.spec.ts

@@ -202,6 +202,24 @@ describe("loki", () => {
       users.remove(testObject as any);
       expect(userCount1).toEqual(users.count());
     });
+
+    it("meta not set on returned objects", function() {
+      const tdb = new Loki("test.db");
+      const coll = tdb.addCollection<{a: number, b: number}>("tc", { disableMeta: true });
+
+      // verify single insert return objs do not have meta set
+      const obj = coll.insert({ a: 1, b: 2 });
+      expect(obj.hasOwnProperty("meta")).toEqual(false);
+      expect(obj.hasOwnProperty("$loki")).toEqual(true);
+
+      // verify batch insert return objs do not have meta set
+      const objs = coll.insert([{ a: 2, b: 3 }, { a: 3, b: 4 }]);
+      expect(Array.isArray(objs));
+      objs.forEach((o) => {
+        expect(o.hasOwnProperty("meta")).toEqual(false);
+        expect(o.hasOwnProperty("$loki")).toEqual(true);
+      });
+    });
   });
 
   describe("dot notation", () => {

packages/loki/src/collection.ts

@@ -110,6 +110,10 @@ export class Collection<TData extends object = object, TNested extends object =
    */
   public cloneMethod: CloneMethod;
 
+  /**
+   * If set to true we will not maintain a meta property for a document.
+   */
+  private disableMeta: boolean;
 
   /**
    * Disable track changes.
@@ -168,19 +172,34 @@ export class Collection<TData extends object = object, TNested extends object =
    * @param {string[]} [options.indices=[]] - array property names to define binary indexes for
    * @param {boolean} [options.adaptiveBinaryIndices=true] - collection indices will be actively rebuilt rather than lazily
    * @param {boolean} [options.asyncListeners=false] - whether listeners are invoked asynchronously
+   * @param {boolean} [options.disableMeta=false] - set to true to disable meta property on documents
    * @param {boolean} [options.disableChangesApi=true] - set to false to enable Changes API
    * @param {boolean} [options.disableDeltaChangesApi=true] - set to false to enable Delta Changes API (requires Changes API, forces cloning)
    * @param {boolean} [options.clone=false] - specify whether inserts and queries clone to/from user
    * @param {boolean} [options.serializableIndices =true] - converts date values on binary indexed property values are serializable
    * @param {string} [options.cloneMethod="deep"] - the clone method
    * @param {number} [options.transactional=false] - ?
-   * @param {number} [options.ttl=] - ?
-   * @param {number} [options.ttlInterval=] - time interval for clearing out 'aged' documents; not set by default.
+   * @param {number} [options.ttl=] - age of document (in ms.) before document is considered aged/stale.
+   * @param {number} [options.ttlInterval=] - time interval for clearing out 'aged' documents; not set by default
    * @param {FullTextSearch.FieldOptions} [options.fullTextSearch=] - the full-text search options
    * @see {@link Loki#addCollection} for normal creation of collections
    */
   constructor(name: string, options: Collection.Options<TData> = {}) {
     super();
+
+    // Consistency checks.
+    if (options && options.disableMeta === true) {
+      if (options.disableChangesApi === false) {
+        throw new Error("disableMeta option cannot be passed as true when disableChangesApi is passed as false");
+      }
+      if (options.disableDeltaChangesApi === false) {
+        throw new Error("disableMeta option cannot be passed as true when disableDeltaChangesApi is passed as false");
+      }
+      if (typeof options.ttl === "number" && options.ttl > 0) {
+        throw new Error("disableMeta option cannot be passed as true when ttl is enabled");
+      }
+    }
+
     // the name of the collection
     this.name = name;
     // the data held by the collection
@@ -233,6 +252,9 @@ export class Collection<TData extends object = object, TNested extends object =
     // .
     this.asyncListeners = options.asyncListeners !== undefined ? options.asyncListeners : false;
 
+    // .
+    this.disableMeta = options.disableMeta !== undefined ? options.disableMeta : false;
+
     // .
     this.disableChangesApi = options.disableChangesApi !== undefined ? options.disableChangesApi : true;
 
@@ -340,6 +362,7 @@ export class Collection<TData extends object = object, TNested extends object =
       adaptiveBinaryIndices: this.adaptiveBinaryIndices,
       transactional: this.transactional,
       asyncListeners: this.asyncListeners,
+      disableMeta: this.disableMeta,
       disableChangesApi: this.disableChangesApi,
       disableDeltaChangesApi: this.disableDeltaChangesApi,
       cloneObjects: this.cloneObjects,
@@ -358,6 +381,7 @@ export class Collection<TData extends object = object, TNested extends object =
     coll.adaptiveBinaryIndices = obj.adaptiveBinaryIndices !== undefined ? (obj.adaptiveBinaryIndices === true) : false;
     coll.transactional = obj.transactional;
     coll.asyncListeners = obj.asyncListeners;
+    coll.disableMeta = obj.disableMeta;
     coll.disableChangesApi = obj.disableChangesApi;
     coll.cloneObjects = obj.cloneObjects;
     coll.cloneMethod = obj.cloneMethod || "deep";
@@ -757,8 +781,8 @@ export class Collection<TData extends object = object, TNested extends object =
     // if configured to clone, do so now... otherwise just use same obj reference
     const obj = this.cloneObjects ? clone(doc, this.cloneMethod) : doc;
 
-    if ((<any>obj).meta === undefined) {
-      (<any>obj).meta = {
+    if (!this.disableMeta && (obj as Doc<TData>).meta === undefined) {
+      (obj as Doc<TData>).meta = {
         revision: 0,
         created: 0
       };
@@ -944,7 +968,9 @@ export class Collection<TData extends object = object, TNested extends object =
 
       const newDoc = obj as Doc<TData>;
       newDoc.$loki = this.maxId;
-      newDoc.meta.version = 0;
+      if (!this.disableMeta) {
+        newDoc.meta.version = 0;
+      }
 
       const constrUnique = this.constraints.unique;
       for (const key in constrUnique) {
@@ -1194,7 +1220,7 @@ export class Collection<TData extends object = object, TNested extends object =
     let len;
     let idx;
 
-    if (!obj) {
+    if (this.disableMeta || !obj) {
       return;
     }
 
@@ -1224,7 +1250,7 @@ export class Collection<TData extends object = object, TNested extends object =
   }
 
   private _updateMeta(obj: Doc<TData>) {
-    if (!obj) {
+    if (this.disableMeta || !obj) {
       return;
     }
     obj.meta.updated = (new Date()).getTime();
@@ -2053,6 +2079,7 @@ export namespace Collection {
     indices?: (keyof TData)[];
     adaptiveBinaryIndices?: boolean;
     asyncListeners?: boolean;
+    disableMeta?: boolean;
     disableChangesApi?: boolean;
     disableDeltaChangesApi?: boolean;
     clone?: boolean;
@@ -2095,6 +2122,7 @@ export namespace Collection {
     adaptiveBinaryIndices: boolean;
     transactional: boolean;
     asyncListeners: boolean;
+    disableMeta: boolean;
     disableChangesApi: boolean;
     disableDeltaChangesApi: boolean;
     cloneObjects: boolean;

packages/loki/src/loki.ts

@@ -242,10 +242,13 @@ export class Loki extends LokiEventEmitter {
    * @param {array} [options.exact=[]] - array of property names to define exact constraints for
    * @param {array} [options.indices=[]] - array property names to define binary indexes for
    * @param {boolean} [options.asyncListeners=false] - whether listeners are called asynchronously
+   * @param {boolean} [options.disableMeta=false] - set to true to disable meta property on documents
    * @param {boolean} [options.disableChangesApi=true] - set to false to enable Changes Api
+   * @param {boolean} [options.disableDeltaChangesApi=true] - set to false to enable Delta Changes API (requires Changes API, forces cloning)
    * @param {boolean} [options.clone=false] - specify whether inserts and queries clone to/from user
    * @param {string} [options.cloneMethod=CloneMethod.DEEP] - the clone method
-   * @param {int} options.ttlInterval - time interval for clearing out 'aged' documents; not set by default.
+   * @param {number} [options.ttl=] - age of document (in ms.) before document is considered aged/stale
+   * @param {number} [options.ttlInterval=] - time interval for clearing out 'aged' documents; not set by default
    * @returns {Collection} a reference to the collection which was just added
    */
   public addCollection<T extends object = object, U extends object = object>(name: string, options: Collection.Options<T> = {}): Collection<T, U> {