Meteor Collection Hooks

Extends Mongo.Collection with onInsert, onUpdate and onRemove hooks.

Getting Started

Installation:

meteor add pmogollons:collection-hooks

All hooks run after the operation has completed, so you can safely modify the document in the hook without affecting the operation.

onInsert

1Collection.onInsert(function ({ userId, doc }) {
2    // Code here run after the insert operation has completed
3}, {
4  // You can set the doc fields the hook will receive. If not set, it will return all fields.
5  docFields: {
6    field1: 1,
7    field2: 1
8  }
9});

onUpdate

1Collection.onUpdate(function ({ userId, doc, previousDoc }) {
2    // Code here run after the update operation has completed
3}, {
4  // You can set the doc fields the hook will receive. If not set, it will return all fields.
5  docFields: {
6    field1: 1,
7    field2: 1
8  },
9  // If set to true, the hook will receive the previous document
10  fetchPrevious: true
11});

onRemove

1Collection.onRemove(function ({ userId, doc }) {
2    // Code here run after the remove operation has completed
3}, {
4  // You can set the doc fields the hook will receive. If not set, it will return all fields.
5  docFields: {
6    field1: 1,
7    field2: 1
8  }
9});

onBeforeInsert

1Collection.onInsert(function ({ userId, doc }) {
2  // Code here run after the insert operation has completed
3}, {
4  // You can set the doc fields the hook will receive. If not set, it will return all fields.
5  docFields: {
6    field1: 1,
7    field2: 1
8  }
9});

Direct access (circumventing hooks)

1Collection.insertAsync(doc, { skipHooks: true });
2Collection.updateAsync(query, mod, { skipHooks: true });
3Collection.removeAsync(query, { skipHooks: true });

Why only onBeforeInsert?

Well we didn't had the use case for the other before hooks and didn't want to add more complexity to the package.

Additional notes

• If you throw an error on the onBeforeInsert hook the insert operation will be cancelled.
• By default, previousDoc is not fetched on onUpdate. If you want to fetch it, set fetchPrevious to true.
• If you want to fetch only specific fields on the doc, set the docFields option to the mongo projection you want to fetch.
• It is quite normal for userId to sometimes be unavailable to hook callbacks in some circumstances. For example, if an update is fired from the server with no user context, the server certainly won't be able to provide any particular userId.
• Hooks can only be defined on the server.
• Hooks fetch the docs on insert, update and remove operations. So for each op you will get one more op for fetching docs and one more if you want to fetch the previous doc on update.