metadata: [
  {
    type: 'li-boolean',
    config: {
      // common
      hideFromForm: false                      // optional, default: false
    }
    ui: {
      label: 'foo',                            // optional, takes camelized name otherwise
      config: {
        readOnly: true                         // optional, default: false
      }
    }
  }
]

metadata: [
  {
    handle: 'color',
    type: 'li-color',
    config: {
      // common
      hideFromForm: false,                     // optional, default: false
      required: true,                          // optional, default: false
      requiredErrorMessage: 'Provide a value', // optional
      // specific
      translatable: true                       // optional, default: false, translations are only supported for data-record and mediaLibrary
    },
    ui: {
      label: 'your label',
      config: {
        useInputTypeColor: false,              // optional, default: true, shows a color picker
        readOnly: true,                        // optional, default: false
        placeholder: 'foo',                    // optional, takes camelized name otherwise
      }
    }
  }
]

metadata: [
  {
    handle: 'date',
    type: 'li-date',
    config: {
      // common
      hideFromForm: false,                     // optional, default: false
      required: true,                          // optional, default: false
      requiredErrorMessage: 'Provide a value'  // optional
      translatable: false                      // optional, default: false
    },
    ui: {
      label: 'foo',                   // optional, takes camelized name otherwise
      config: {
        readOnly: true                // optional, default: false
      }
    }
  }
]

metadata: [
  {
    handle: 'date',
    type: 'li-datetime',
    config: {
      // common
      hideFromForm: false,                     // optional, default: false
      required: true,                          // optional, default: false
      requiredErrorMessage: 'Provide a value'  // optional
    },
    ui: {
      label: 'foo',                   // optional, takes camelized name otherwise
      config: {
        readOnly: true                // optional, default: false
      }
    }
  }
]

{
  js: [
    {
      src: <String>,
      code: <String>,
      inline: <Boolean>,
      library: <String>,
      namespace: <String>,
      componentIds: [
        <String>
      ]
    }
  ],
  css: [
    {
      src: <String>,
      code: <String>,
      inline: <Boolean>,
      library: <String>,
      namespace: <String>,
      componentIds: [
        <String>
      ]
    }
  ]
}

{
  id: <Integer>,
  publicationId: <Integer>,
  platformId: <Integer>,
  categoryId: <Integer>,
  publicationStatusId: <Integer> // Added in: release-2022-07
}

metadata: [
  {
    handle: 'desknet',
    type: 'li-desknet-integration',
    config: {
      // Added in: release-2022-07
      publicationStatus: {
        fallbackPublicationStatusId: '2',
        // The order of matchers is important. The array is iterated through from first to last,
        // with the publicationStatusId taken from the earliest document state match.
        matchers: [
          {
            type: 'publication',
            value: 'published', // Only 'published' supported
            publicationStatusId: '5'
          },
          {
            type: 'task',
            taskName: 'proofreading',
            value: 'completed', // 'requested', 'accepted', 'completed'
            publicationStatusId: '4'
          },
          {
            type: 'metadata',
            propertyName: 'prepared',
            value: true, // <String>, <Number>, <Boolean>, <Array>, <Object>
            publicationStatusId: '3'
          }
        ]
      }
    },
    ui: {
      label: 'Desk-Net',
      config: {
        // Added in: release-2022-07
        publicationStatus: {
          labels: [
            {
              publicationStatusId: '5',
              label: 'Published',
              // optional, any SVG (ideally using viewBox)
              icon: '<svg viewBox="0 0 9 9" xmlns="http://www.w3.org/2000/svg"><path d="M0 0h9v9H0z"/></svg>',
              // optional, any CSS colour string
              color: '#f00'
            }
          ]
        }
      }
    }
  }
]

{
  platforms: [
    {
      platformId: <Integer>,
      categoryId: <Integer>
    }
  ],
  date: <ISO8601 String>
}

metadata: [
  {
    handle: 'desknetSchedule',
    type: 'li-desknet-schedule',
    config: {
      filters: {
        linkedDocumentsOnly: true,
        elementStatusIds: [1, 2, 10322, 10332],
        publicationStatusIds: [5]
      }),
      desknetExternalElementIdMetadataPath: 'myExternalSystem.id',
      automaticPlacementCreationFlowHandle: 'myDesknetGenerateContentFlow'
    },
    ui: {
      label: 'Desk-Net Schedule',
      config: {
        placeholder: 'Select a Desk-Net platform or category',
        useDashboard: 'articlesSimple'
      }
    }
  }
]

{
  reference: {
    id: <String>
  }
}

// contentType[].metadata / mediaType[].metadata
metadata: [
  {
    handle: 'references',
    type: 'li-document-references',
    config: {
      // common
      hideFromForm: false,                     // optional, default: false
      required: true,                          // optional, default: false
      requiredErrorMessage: 'Provide a value', // optional
      // specific
      documentType: 'article',                 // optional, one of article, page, data-record
      contentType: 'my-content-type'           // optional, filters the document selection
      published: true,                         // optional, shorthand for publication displayFilter, default: false
    },
    ui: {
      label: 'foo',                  // optional, takes camelized name otherwise
      config: {
        style: 'default',            // optional, defaults to 'default'. Other options: 'teaser'
        useDashboard: '',            // optional, reference to a custom dashboard
        baseFilters: [],             // optional, invisible filters and applied to every search (including the default result list)
        displayFilters: [],          // optional, filters that the user can set in the UI (below the search input)
      }
    }
  }
]

{
  $ref: 'documents',
  references: [{
    id: <String>
  }]
}

// contentType[].metadata / mediaType[].metadata
metadata: [
  {
    handle: 'reference',
    type: 'li-document-references',
    config: {
      // common
      hideFromForm: false,                     // optional, default: false
      required: true,                          // optional, default: false
      requiredErrorMessage: 'Provide a value', // optional
      // specific
      documentType: 'article',                 // optional, one of article, page, data-record
      contentType: 'my-content-type'           // optional, filters the document selection
      published: true,                         // optional, shorthand for publication baseFilter, default: false
    },
    ui: {
      label: 'foo',                  // optional, takes camelized name otherwise
      config: {
        // style: 'default' -> default for metadata
        // style: 'teaser' -> default for include paramsSchema
        style: 'default',
        useDashboard: '',            // optional, reference to a custom dashboard
        baseFilters: [],             // optional, invisible filters and applied to every search (including the default result list)
        displayFilters: [],          // optional, filters that the user can set in the UI (below the search input)
      }
    }
  }
]

// contentType[].metadata / mediaType[].metadata
metadata: [
  {
    handle: 'tags',
    type: 'li-enum',
    config: {
      // common
      hideFromForm: false,                     // optional, default: false
      required: true,                          // optional, default: false
      requiredErrorMessage: 'Provide a value', // optional
      // specific
      dataProvider: {                          // required
        type: 'labelValuePair',                // required
        items: [
          {label: 'Tag A', value: 'a'},
          {label: 'Tag B', value: 'b', isDefault: true}, // isDefault sets the value if document opened the first time
          {label: 'Tag C', value: 'c'}
        ]
      }
    },
    ui: {
      label: 'foo',                   // optional, takes camelized name otherwise
      config: {
        readOnly: true,               // optional, default: false
        placeholder: 'foo',           // optional, takes camelized name otherwise
      }
    }
  }
]

// contentType[].metadata / mediaType[].metadata
metadata: [
  {
    handle: 'externalId',
    type: 'li-external-id',
    config: {
      // no config values are allowed
    },
    ui: {
      // no ui config values are allowed
    }
  }
]

{
  userId: <Integer>,
  userName: <String>,
  locktime: <ISO8601 String>,
  tabId: <String>
}

{
  originalUrl: <String>,
  url: <String>,
  mediaId: <String>,
  height: <Integer>,
  width: <Integer>,
  mimeType: <String>,
  imageService: <String>,
  crops: [
    <Object>
  ],
  focalPoint: {
    x: <Integer>,
    y: <Integer>
  }
}

{
  "$ref": "documents",
  "references": [
    {
      "id": "359",
      "inactive": true
    },
    {
      "id": "358"
    }
  ]
}

metadata: [{
  handle: 'pages',
  type: 'li-issue-management',
  ui: {
    config: {
      documentCreationFlows: [{
        useDocumentCreationFlow: 'digitaleAusgabePage' // document creation flow function to call, when the "add page" button is clicked - see https://docs.livingdocs.io/guides/editor/document-creation-flow/#goal
      }]
    }
  }
}]

{
  contentVersion: <String>,
  concepts: [
    {
      weight: <Number>,
      title: <String>,
      slug: <String>,
      type: <String>,
      uuid: <String>,
      inappropriate: <Boolean>,
      userAdded: <Boolean>
    }
  ]
}

metadata: [
  {
    handle: 'integer',
    type: 'li-integer',
    config: {
      // common
      hideFromForm: false,                     // optional, default: false
      required: true,                          // optional, default: false
      requiredErrorMessage: 'Provide a value', // optional
      // specific
      minValue: 1,                             // optional
      maxValue: 50                             // optional
      translatable: true,                      // optional, default: false, translations are only supported for data-record and mediaLibrary
      dataProvider: {                          // optional, added in release-2023-03
        // Option 1 - list of items
        type: 'labelValuePair',
        items: [
          {label: 'A', value: 1},
          {label: 'B', value: 2, isDefault: true}, // isDefault sets the value if document opened the first time
          {label: 'C', value: 3}
        ]
        // Option 2 - DataSource
        dataSource: 'labelValuePairDataSource'
      }
    },
    ui: {
      label: 'foo',                   // optional, takes camelized name otherwise
      config: {
        placeholder: 'bar',           // optional, takes camelized name otherwise
        readOnly: true,               // optional, default: false
      }
    }
  }
]

{
  locale: <String>,
  label: <String>,
  groupId: <String>
}

metadata: [
  {
    handle: 'language',
    type: 'li-language'
  }
]

// contentType[].metadata / mediaType[].metadata
metadata: [
  {
    handle: 'language',
    type: 'li-metadata-translations',
    ui: {
      component: 'liMetaSelectForm',
      service: 'languageSelection'
    }
  }
]

{
  crops: [
    {
      name: <String>,
      x: <Integer>,
      y: <Integer>,
      width: <Integer>,
      height: <Integer>,
      isAutomatic: <Boolean>
    }
  ],
  focalPoint: {
    x: <Integer>,
    y: <Integer>
  }
}

metadata: [
  {
    handle: 'otherIds',
    type: 'li-numeric-list',
    config: {
      // common
      required: true,                                   // optional, default: false
      requiredErrorMessage: 'Custom required message',  // optional
      // specific
      maxItems: 5,                                      // optional
    },
    ui: {
      label: 'foo',                   // optional, takes camelized name otherwise
      config: {
        placeholder: 'bar',           // optional, takes capitalized handle name otherwise
        readOnly: true                // optional, default: false
      }
    }
  }
]

{
  originalUrl: <String>,
  url: <String>,
  mediaId: <String>,
  height: <Integer>,
  width: <Integer>,
  mimeType: <String>,
  imageService: <String>,
  crops: [
    {
      name: <String>,
      x: <Integer>,
      y: <Integer>,
      width: <Integer>,
      height: <Integer>,
      isAutomatic: <Boolean>
    }
  ]
}

{
  messages: [{
    id: <String>,
    sentAt: <ISO8601 String>,
    userId: <Number>,
    params: <Object>
  }]
}

metadata: [
  {
    type: 'li-push-messages',
    handle: 'myPushMessages',             // Name of the metadata field
    ui: {
      label: 'Push Me'                    // Optional, controls button label on Table Dashboards
    },
    config: {
      paramsSchema: [                     // Defines schema of message object
        {
          type: 'li-text',                // One of: li-text, li-boolean, li-integer, li-date, li-datetime
          handle: 'messageText',          // Property name on message object
          config: {                       // Config based on type (li-text here)
            required: true,
            maxLength: 120,
            recommendedMaxLength: 100
          }
        }
      ],
      handlerName: 'myPushMessageHandler' // Optional, name of the registered function to send the message
    }
  }
]

columns: [
  ...,
  {
    label: 'My push messages',
    metadataPropertyName: 'myPushMessages',
    minWidth: 70,
    growFactor: 1,
    priority: 1
  }
]

module.exports = function (liServer) {
  // Register function after server initialization
  liServer.registerInitializedHook(async function () {

    const log = liServer.log.child({ns: 'push-messages-hooks'})
    const pushMessagesApi = liServer.features.api('li-documents').pushMessages
    
    pushMessagesApi.registerPushMessageHandler({
      // Name must be unique across projects
      name: 'myPushMessageHandler',

      /**
       * @async
       * @param {object} args
       * @param {object} args.projectConfig
       * @param {number} args.userId
       * @param {string} args.documentId
       * @param {string} args.metadataPropertyName
       * @param {string} args.pushMessageId - Id the push message will have
       * @param {object} args.params - The message object, following paramsSchema
       * @return {Promise<void>}
       */
      async handler (args) {
        log.info(
          `Handling push message for metadata property name "${args.metadataPropertyName}"`
        )
      }
    })
  })
}

{
  $ref: 'documents',
  references: [{
    id: <String>
  }]
}

{
  $ref: 'document',
  reference: {
    id: <String>
  }
}

metadata: [
  {
    handle: 'reference',
    type: 'li-reference',
    config: {
      // common
      hideFromForm: false,                     // optional, default: false
      required: true,                          // optional, default: false
      requiredErrorMessage: 'Provide a value', // optional
      // specific
      documentType: 'data-record',             // optional
      contentType: 'author',                   // optional
      prefillAuthor: true                      // optional, default: false
      published: true,                         // optional, shorthand for publication baseFilter, default: false
    },
    ui: {
      label: 'foo',                            // optional, takes camelized name otherwise
      component: 'liMetaReferenceForm',
      config: {
        displayFilters: ['timeRange']
      }
    }
  }
]

{
  contentVersion: <String>,
  entities: [{
    id: <String>,
    type: <String>,
    name: <String>,
    score: <Number>,
    inappropriate: <Boolean>,
    userAdded: <Boolean>
  }]
}

// contentType[].metadata / mediaType[].metadata
metadata: [
  {
    handle: 'myStringList',
    type: 'li-string-list',
    config: {
      // common
      hideFromForm: false,                     // optional, default: false
      required: true,                          // optional, default: false
      requiredErrorMessage: 'Provide a value', // optional
      // specific
      dataProvider: { // required
        // Option 1 - list of items
        type: 'labelValuePair',
        items: [
          {label: 'Item A', value: 'a'},
          {label: 'Item B', value: 'b', isDefault: true}, // isDefault sets the value if document opened the first time
          {label: 'Item C', value: 'c'}
        ]
        // Option 2 - DataSource
        dataSource: 'labelValuePairDataSource'
      }
    },
    ui: {
      label: 'foo', // optional, takes camelized name otherwise
      config: {
        readOnly: true, // optional, default: false
      }
    }
  }
]

// contentType[].metadata / mediaType[].metadata
metadata: [
  {
    handle: 'targetLength',
    type: 'li-target-length',
    // optional, allows picking a step instead of entering an exact number
    ui: {
      config: {
        acceptedCharacterDifference: 20, // Range above and below `value` considered accepted
        steps: [
          {
            label: 'S', // use a short one, e.g. "S" "M" "L"
            value: 100 // number of characters
          },
          {
            label: 'M',
            value: 200
          }
        ],
        // optional, allows the input of an exact number besides picking a step
        allowAnyNumber: true
      }
    }
  }
]

metadata: [
  {
    handle: 'title',
    type: 'li-text',
    config: {
      // common
      hideFromForm: false,                     // optional, default: false
      required: true,                          // optional, default: false
      requiredErrorMessage: 'Provide a value', // optional
      // specific
      minLength: 100,                          // optional, added in release-2022-09
      maxLength: 200,                          // optional
      recommendedMinLength: 110,               // optional, added in release-2022-09
      recommendedMaxLength: 150,               // optional, added in release-2022-09
      allowNewlines: false                     // default: undefined, added in release-2022-09, validated if set. Effect on ui: newlines are stripped uf not true and ui.config.rows is undefined and ui.component is not liMetaTextareaForm
      useAsTitle: true,                        // default: false, synchronises the value with document.title if true
      translatable: true,                      // optional, default: false, translations are only supported for data-record and mediaLibrary
      dataProvider: {                          // optional
        // Option 1 - list of items
        type: 'labelValuePair',
        items: [
          {label: 'Item A', value: 'a'},
          {label: 'Item B', value: 'b', isDefault: true}, // isDefault sets the value if document opened the first time
          {label: 'Item C', value: 'c'}
        ]
        // Option 2 - DataSource
        dataSource: 'labelValuePairDataSource'
      }
    },
    ui: {
      label: 'foo',                   // optional, takes camelized name otherwise
      config: {
        placeholder: 'bar',           // optional, takes camelized name otherwise
        readOnly: true,               // optional, default: false
        rows: 10                      // optional, only applicable for LiMetaFormTextarea, integer, 5 by default
      }
    }
  }
]

// schweiz -> link
//   zürich -> link
//   bern -> document
// deutschland -> group
//   hamburg -> link
//   berlin -> document
[
  {
    id: 'menu-schweiz',
    label: 'Schweiz',
    type: 'link',
    href: '/schweiz',
    items: [
      {
        id: 'menu-zuerich',
        label: 'Zürich',
        type: 'link',
        href: '/zuerich'
      },
      {
        id: 'menu-bern',
        label: 'Bern',
        type: 'document',
        reference: {
          id: '42'
        }
      }
    ]
  },
  {
    id: 'menu-deutschland',
    label: 'Deutschland',
    type: 'group',
    items: [
      {
        id: 'menu-hamburg',
        label: 'Hamburg',
        type: 'link',
        href: '/hamburg'
      },
      {
        id: 'menu-berlin',
        label: 'Berlin',
        type: 'document',
        reference: {
          id: '991'
        }
      }
    ]
  }
]

metadata: [
  {
    handle: 'tree',
    type: 'li-tree',
    config: {
      // common
      hideFromForm: false,                          // optional, default: false
      required: true,                               // optional, default: false
      requiredErrorMessage: 'Provide a value',      // optional
      // specific
      maxDepth: 3,                                  // default: undefined | tree depth
      allowedTypes: ['group', 'document', 'link'],  // default: ['group', 'document', 'link']

      // settings for document link
      document: {
        contentType: ['regular'],                   // default: all   | only be able to link contentType 'regular' | string or array of strings
        published: true                             // default: false | only be able to link published document
      }
    },
    ui: {
      label: 'foo',                                 // optional, takes camelized name otherwise
      config: {
        readOnly: true,                             // optional, default: false

        document: {                                 // define a Dashboard with filters
          useDashboard: 'my-dashboard',             //   reference to a custom dashboard
          baseFilters: [],                          //   https://docs.livingdocs.io/reference-docs/editor-extensions/editor-configuration/base-filter/
          displayFilters: []                        //   https://docs.livingdocs.io/reference-docs/editor-extensions/editor-configuration/display-filter/
        }
      }
    }
  }
]

{
  commands: [{
    assetKey: <String>,
    commandId: <String>,
    createdAt: <String>,
    state: <String>,
    errorMessage: <String>,
    progress: <Number>
  }],
  transcodings: [{
    assetKey: <String>
  }]
}

metadata: [
  {
    handle: 'transcoding',
    type: 'li-transcoding-state',
    ui: {
      label: 'My Transcoding'     // optional, takes "Transcoding State" otherwise
    }
  }
]

{
  $ref: 'video',
  reference: {
    id: <String>,
    posterImageId: <String>
  }
}

paramsSchema: [
  {
    handle: 'video',
    type: 'li-video-reference',
    config: {
      // common
      hideFromForm: false,                     // optional, default: false
      required: true,                          // optional, default: false
      requiredErrorMessage: 'Provide a value', // optional
      // specific
      translatable: true,                      // optional, default: false, translations are only supported for data-record and mediaLibrary
    },
    ui: {
      config: {
        posterImageUploadMediaType: 'image2',  // optional, default: 'image'
      }
    }
  }
]

metadata: [
  {
    handle: 'teaserImage',
    type: 'li-image',
    config: {
      // common
      hideFromForm: false,                     // optional, default: false
      required: true,                          // optional, default: false
      requiredErrorMessage: 'Provide a value', // optional
      // specific
      imageRatios: ['16:9', '1:1']
    },
    ui: {
      component: 'liMetaImageForm'
    }
  }
]

fieldExtractor: [
  {
    // the metadata field 'teaserImage' is the target of this extraction
    identifier: 'teaserImage',
    // the extraction is of type image
    type: 'image',
    // extract from component 'image' the value in the directive 'image'
    matches: ['image.image']
  }
]

metadata: [
  {
    ...,
    ui: {
      component: 'liMetaDatetimeForm',
      service: 'customServicePlugin',  // optional
      label: 'foo'                     // optional, takes camelized name otherwise
    }
  }
]

{
  // set the date, possibly applying formatting options
  setDate (identifier, value) {},

  // get the date, possibly applying formatting options
  getDate (identifier) {},

  // this lets you define what dates a user can select in the UI. Handy if you want for example
  // to disallow past dates.
  isValidDate (date) {}
}

metadata: [
  {
    ...,
    type: 'li-reference-list',
    config: {
      // common
      hideFromForm: false,                     // optional, default: false
      required: true,                          // optional, default: false
      requiredErrorMessage: 'Provide a value', // optional
      // specific
      referenceType: 'documents'
      displayFilters: []
    },
    ui: {
      component: 'liMetaReferenceForm',
      config: {
        sortable: true, // enable sorting by drag and drop
        displayFilters: [] // enable display filters
      }
    }
  }
]

metadata: [
  {
    ...,
    type: 'li-list-reference',
    config: {
      // common
      hideFromForm: false,                     // optional, default: false
      required: true,                          // optional, default: false
      requiredErrorMessage: 'Provide a value', // optional
      // specific
      enableCount: true,      // enable UI configuration of number of articles (default: false)
      defaultCount: 3,        // number of articles shown by default (default: 3)
      minCount: 2,            // minimum number of articles
      maxCount: 6,            // maximum number of articles
      enableListEditing: true // allow to create/edit list inline (default: false)
    }
  }
]