umbraco-collection

name	umbraco-collection
description	Implement collections in Umbraco backoffice using official docs
version	1.1.0
location	managed
allowed-tools	Read, Write, Edit, WebFetch

Umbraco Collection

What is it?

A Collection displays a list of entities in the Umbraco backoffice with built-in support for multiple views (table, grid), filtering, pagination, selection, and bulk actions. Collections connect to a repository for data and provide a standardized way to browse and interact with lists of items.

Documentation

Always fetch the latest docs before implementing:

• Main docs: https://docs.umbraco.com/umbraco-cms/extend-your-project/backoffice-extensions/extending-overview/extension-types/collections
• Collection View: https://docs.umbraco.com/umbraco-cms/extend-your-project/backoffice-extensions/extending-overview/extension-types/collections/collection-view
• Foundation: https://docs.umbraco.com/umbraco-cms/extend-your-project/backoffice-extensions/foundation
• Extension Registry: https://docs.umbraco.com/umbraco-cms/extend-your-project/backoffice-extensions/extending-overview/extension-registry

Collection Architecture

A complete collection consists of these components:

collection/
├── manifests.ts              # Main collection manifest
├── constants.ts              # Alias constants
├── types.ts                  # Item and filter types
├── my-collection.context.ts  # Collection context (extends UmbDefaultCollectionContext)
├── my-collection.element.ts  # Collection element (extends UmbCollectionDefaultElement)
├── repository/
│   ├── manifests.ts
│   ├── my-collection.repository.ts    # Implements UmbCollectionRepository
│   └── my-collection.data-source.ts   # API calls
├── views/
│   ├── manifests.ts
│   └── table/
│       └── my-table-view.element.ts   # Table view
└── action/
    ├── manifests.ts
    └── my-action.element.ts           # Collection action

Reference Example

The Umbraco source includes a working example:

Location: /Umbraco-CMS/src/Umbraco.Web.UI.Client/examples/collection/

This example demonstrates a complete custom collection with repository, views, and context. Study this for production patterns.

Related Foundation Skills

• Repository Pattern: Collections require a repository for data access

  • Reference skill: umbraco-repository-pattern

• Context API: For accessing collection context in views

  • Reference skill: umbraco-context-api

• State Management: For understanding observables and reactive data

  • Reference skill: umbraco-state-management

Workflow

1. Fetch docs - Use WebFetch on the URLs above
2. Ask questions - What entities? What repository? What views needed? What actions?
3. Define types - Create item model and filter model interfaces
4. Create repository - Implement data source and repository
5. Create context - Extend UmbDefaultCollectionContext if custom behavior needed
6. Create views - Implement table/grid views
7. Create actions - Add collection actions (create, refresh, etc.)
8. Explain - Show what was created and how to test

Complete Example

1. Constants (constants.ts)

export const MY_COLLECTION_ALIAS = 'My.Collection';
export const MY_COLLECTION_REPOSITORY_ALIAS = 'My.Collection.Repository';

2. Types (types.ts)

export interface MyCollectionItemModel {
  unique: string;
  entityType: string;
  name: string;
  // Add other fields
}

export interface MyCollectionFilterModel {
  skip?: number;
  take?: number;
  filter?: string;
  orderBy?: string;
  orderDirection?: 'asc' | 'desc';
  // Add custom filters
}

3. Data Source (repository/my-collection.data-source.ts)

import type { MyCollectionItemModel, MyCollectionFilterModel } from '../types.js';
import type { UmbCollectionDataSource } from '@umbraco-cms/backoffice/collection';
import type { UmbControllerHost } from '@umbraco-cms/backoffice/controller-api';

export class MyCollectionDataSource implements UmbCollectionDataSource<MyCollectionItemModel> {
  #host: UmbControllerHost;

  constructor(host: UmbControllerHost) {
    this.#host = host;
  }

  async getCollection(filter: MyCollectionFilterModel) {
    // Call your API here
    const response = await fetch(`/api/my-items?skip=${filter.skip}&take=${filter.take}`);
    const data = await response.json();

    const items: MyCollectionItemModel[] = data.items.map( ({
      : item.,
      : ,
      : item.,
    }));

     { : { items, : data. } };
  }
}

4. Repository (repository/my-collection.repository.ts)

import type { MyCollectionFilterModel } from '../types.js';
import { MyCollectionDataSource } from './my-collection.data-source.js';
import { UmbRepositoryBase } from '@umbraco-cms/backoffice/repository';
import type { UmbCollectionRepository } from '@umbraco-cms/backoffice/collection';
import type { UmbControllerHost } from '@umbraco-cms/backoffice/controller-api';

export class MyCollectionRepository extends UmbRepositoryBase implements UmbCollectionRepository {
  #dataSource: MyCollectionDataSource;

  constructor(host: UmbControllerHost) {
    super(host);
    this.#dataSource = new MyCollectionDataSource(host);
  }

  async requestCollection(filter: MyCollectionFilterModel) {
    return this.#dataSource.getCollection(filter);
  }
}

  ;

5. Repository Manifest (repository/manifests.ts)

import { MY_COLLECTION_REPOSITORY_ALIAS } from '../constants.js';

export const manifests: Array<UmbExtensionManifest> = [
  {
    type: 'repository',
    alias: MY_COLLECTION_REPOSITORY_ALIAS,
    name: 'My Collection Repository',
    api: () => import('./my-collection.repository.js'),
  },
];

6. Collection Context (my-collection.context.ts)

import type { MyCollectionItemModel, MyCollectionFilterModel } from './types.js';
import { UmbDefaultCollectionContext } from '@umbraco-cms/backoffice/collection';
import type { UmbControllerHost } from '@umbraco-cms/backoffice/controller-api';

// Default view alias - must match one of your collectionView aliases
const MY_TABLE_VIEW_ALIAS = 'My.CollectionView.Table';

export class MyCollectionContext extends UmbDefaultCollectionContext<
  MyCollectionItemModel,
  MyCollectionFilterModel
> {
  constructor(host: UmbControllerHost) {
    super(host, MY_TABLE_VIEW_ALIAS);
  }

  // Override or add custom methods if needed
}

export { MyCollectionContext as api };

7. Collection Element (my-collection.element.ts)

import { customElement } from '@umbraco-cms/backoffice/external/lit';
import { UmbCollectionDefaultElement } from '@umbraco-cms/backoffice/collection';

@customElement('my-collection')
export class MyCollectionElement extends UmbCollectionDefaultElement {
  // Override renderToolbar() to customize header
  // protected override renderToolbar() {
  //   return html`<umb-collection-toolbar slot="header"></umb-collection-toolbar>`;
  // }
}

export default MyCollectionElement;
export { MyCollectionElement as element };

declare global {
  interface HTMLElementTagNameMap {
    'my-collection': MyCollectionElement;
  }
}

8. Table View (views/table/my-table-view.element.ts)

import type { MyCollectionItemModel } from '../../types.js';
import { UMB_COLLECTION_CONTEXT } from '@umbraco-cms/backoffice/collection';
import { css, customElement, html, state } from '@umbraco-cms/backoffice/external/lit';
import { UmbLitElement } from '@umbraco-cms/backoffice/lit-element';
import type { UmbTableColumn, UmbTableConfig, UmbTableItem } from '@umbraco-cms/backoffice/components';

@customElement('my-table-collection-view')
export class MyTableCollectionViewElement extends UmbLitElement {
  @state()
  private _tableItems: Array<UmbTableItem> = [];

  @state()
  private _selection: Array<string> = [];

  #collectionContext?: typeof UMB_COLLECTION_CONTEXT.TYPE;

  private _tableConfig: UmbTableConfig = {
    allowSelection: true,
  };

   : <> = [
    { : , : , :  },
    { : , : , :  },
  ];

  () {
    ();
    .(,  {
      .#collectionContext = context;
      
      context?.();
      .#();
      .#();
    });
  }

  #() {
     (!.#collectionContext) ;

    .(
      .#collectionContext.,
       {
        . = (items  []).( ({
          : item.,
          : ,
          : item.,
          : [
            { : , : item. },
            {
              : ,
              : html`,
            },
          ],
        }));
      },
      ,
    );
  }

  #() {
     (!.#collectionContext) ;

    .(
      .#collectionContext..,
       {
        . = selection  [];
      },
      ,
    );
  }

  #() {
    event.();
     table = event.  ;
    .#collectionContext?..(table.);
  }

  #() {
    event.();
     table = event.  ;
    .#collectionContext?..(table.);
  }

   () {
     html`;
  }
}

  ;

  {
    {
    : ;
  }
}

9. Views Manifest (views/manifests.ts)

import { MY_COLLECTION_ALIAS } from '../constants.js';
import { UMB_COLLECTION_ALIAS_CONDITION } from '@umbraco-cms/backoffice/collection';

export const manifests: Array<UmbExtensionManifest> = [
  {
    type: 'collectionView',
    alias: 'My.CollectionView.Table',
    name: 'My Table Collection View',
    element: () => import('./table/my-table-view.element.js'),
    weight: 200,
    meta: {
      label: 'Table',
      icon: 'icon-list',
      pathName: 'table',
    },
    conditions: [
      {
        alias: UMB_COLLECTION_ALIAS_CONDITION,
        match: MY_COLLECTION_ALIAS,
      },
    ],
  },
];

10. Collection Action (action/manifests.ts)

import { MY_COLLECTION_ALIAS } from '../constants.js';
import { UMB_COLLECTION_ALIAS_CONDITION } from '@umbraco-cms/backoffice/collection';

export const manifests: Array<UmbExtensionManifest> = [
  {
    type: 'collectionAction',
    kind: 'button',
    alias: 'My.CollectionAction.Refresh',
    name: 'Refresh Collection Action',
    element: () => import('./refresh-action.element.js'),
    weight: 100,
    meta: {
      label: 'Refresh',
    },
    conditions: [
      {
        alias: UMB_COLLECTION_ALIAS_CONDITION,
        match: MY_COLLECTION_ALIAS,
      },
    ],
  },
];

11. Main Collection Manifest (manifests.ts)

import { manifests as repositoryManifests } from './repository/manifests.js';
import { manifests as viewManifests } from './views/manifests.js';
import { manifests as actionManifests } from './action/manifests.js';
import { MY_COLLECTION_ALIAS, MY_COLLECTION_REPOSITORY_ALIAS } from './constants.js';

export const manifests: Array<UmbExtensionManifest> = [
  {
    type: 'collection',
    alias: MY_COLLECTION_ALIAS,
    name: 'My Collection',
    api: () => import('./my-collection.context.js'),
    element: () => import('./my-collection.element.js'),
    meta: {
      repositoryAlias: MY_COLLECTION_REPOSITORY_ALIAS,
    },
  },
  ...repositoryManifests,
  ...viewManifests,
  ...actionManifests,
];

Rendering a Collection in a Dashboard

import { html, customElement } from '@umbraco-cms/backoffice/external/lit';
import { UmbLitElement } from '@umbraco-cms/backoffice/lit-element';

@customElement('my-dashboard')
export class MyDashboardElement extends UmbLitElement {
  override render() {
    return html`<umb-collection alias="My.Collection"></umb-collection>`;
  }
}

Built-in Features

The collection system provides these features automatically:

Feature	Description
Selection	UmbSelectionManager on context.selection
Pagination	UmbPaginationManager on context.pagination
Loading state	Observable via context.loading
Items	Observable via context.items
Total count	Observable via context.totalItems
Filtering	Via context.setFilter() method
View switching	Multiple views with UmbCollectionViewManager

Key Condition

Use UMB_COLLECTION_ALIAS_CONDITION to target your collection:

import { UMB_COLLECTION_ALIAS_CONDITION } from '@umbraco-cms/backoffice/collection';

conditions: [
  {
    alias: UMB_COLLECTION_ALIAS_CONDITION,
    match: 'My.Collection',
  },
],

That's it! Always fetch fresh docs, keep examples minimal, generate complete working code.