--- Title: Content metadata component Level: Advanced --- # Content Metadata Component In this tutorial you will learn how to work with the `ContentMetadataComponent`. This component is used to render the standard and custom metadata of generic content item (called a _node_) stored in Alfresco Content Services. With the usual approach "learning by doing", you will see here some practical examples you might find useful in your own application. As a starting point, we will use and customize the [Alfresco Content App](https://github.com/Alfresco/alfresco-content-app). ## About the ContentMetadataComponent As described in the `ContentMetadataComponent` documentation, the `adf-content-metadata-card` tag has some useful attributes, included the `preset` attribute, which is used to point to a collection of aspects/properties to render. Below, you can see the `preset` value requesting to render all the available aspects/properties: ```html ``` As another example, you can see the `preset` value requesting to render all the available aspects/properties related to a specific configuration, named `custom`: ```html ``` All the `preset` configurations are defined in one single configuration file named `app.config.json`, stored in the `src` folder of the project. The `app.config.json` file contains all the configurations of the ADF application, including a section named `content-metadata`, which is used to store the `presets`. The following JSON excerpt gives an example of configuration for the `preset` named `custom`: ```json { "content-metadata": { "presets": { "custom": [ { "title": "APP.CONTENT_METADATA.EXIF_GROUP_TITLE", "items": [ { "aspect": "exif:exif", "properties": [ "exif:pixelXDimension", "exif:pixelYDimension" ] } ] } ] } } } ``` This configuration will show all the listed properties prefixed with `exif:*` in a group titled with the value of the variable `APP.CONTENT_METADATA.EXIF_GROUP_TITLE` for the aspect `exif:exif`. Since this aspect is not related to the node, the component will simply ignore the rendering and nothing will be displayed for these properties. In other words: the aspects to be displayed are calculated as an intersection of the preset aspects and the aspects related to the node. ## Adding and using a new `preset` configuration In this example we will add a new preset configuration and see how it looks in the user interface. ### Adding a new `preset` configuration To add a new `preset` configuration, edit the `src/app.config.json` file and locate the `content-metadata` section. Then, append the following JSON to the `presets` content and save the file: ```json { "content-metadata": { "presets": { "custom": [], "my-preset": [ { "title": "This is my preset", "items": [ { "aspect": "st:siteContainer", "properties": [ "*" ] } ] } ] } } } ``` **Note:** As an alternative to `"properties": ["*"]` (which matches all the properties of the `st:siteContainer` aspect), you can use `"properties": ["st:componentId"]`, which will render one property only. ### Using the `my-preset` configuration Now that the `my-preset` configuration is defined, let's use it in a view of the ADF application ```html ``` ### Properties | Name | Type | Default value | Description | |----------|-----------|---------------|------------------------------------------------------------------------------| | readOnly | `boolean` | false | (optional) This flag sets the metadata in read only mode preventing changes. | ### Viewing the result After saving the html file, open the ADF app in a browser and dive into the `Personal Files > Sites > swsdp` folder of the Alfresco's repository. Once there, select the `documentLibrary` folder (one click only) and click on the view details icon (the `menu_open icon` on the top right). Scrolling down the metadata tab on the right. You will see different panels: `Properties` (already there by default), `Tags`, `Categories` and `grouped properties`. In the following screenshot you can see how the result should look: ![UI_Property_Panel](../docassets/images/UI_property_panel.png) To check it out, double click on the `documentLibrary` folder and select (with one click) the `Presentations` folder. You should see the `This is my preset` group disappear from the metadata panel, because the node doesn't have the `st:siteContainer` aspect.