1 Introduction
Mendix Data Hub enables integration of available data sources from the different applications in an organization into your Mendix apps. This means that new apps can be created using shared datasets that are registered in the Data Hub Catalog. In Studio Pro, this is possible using the integrated functionality of Data Hub Catalog through the Data Hub pane.
You need a license to use Data Hub in Studio Pro. For further information see Data Hub License.
You can search in the Data Hub Catalog through the Data Hub pane to discover data sources that you can use in your app. Via this pane you can add the entities that are exposed in the registered OData services—called Data Sources in Data Hub—into your app’s domain model. These entities are called external entities and are different because they enable the connection to the data associated with the entities in the originating app.
In the Data Hub Catalog, registered published services are referred to as data sources and exposed entities will show the Entity set name and are called datasets.
To display the Data Hub pane, click View > Data Hub.
2 Data Hub Pane Overview
The Data Hub pane is used to search the Data Hub Catalog for entities that can be dragged to the domain model and used in your app and also display the external entities and the associated services that are consumed in your current model.
The following functionality is available in the pane:
- Search – Enter a search string of alphanumeric characters to search in the Data Hub Catalog. The search will be performed on services, entities, attributes, associations, and descriptions in the Catalog.
- Filter – By default, the search is performed on assets in the Production environment. Click the Filter icon to include all other environments such as test, acceptance and also the Mendix free app environment Sandbox in the search.
- View information on the service, its entities, attributes, and associations – When you enter a search term and browse through services, you can view various information on them.
- View services used in your app – Services and the entities that are currently being used in your app are displayed in the Used in your App section and are indicated with a green check-mark in the search results. For more information, see the Used in Your App section below.
2.2 Used in Your App Section
When you do not enter search text in the Data Hub pane, then Used in your App section is displayed. This shows the consumed services and the external entities used in the current app. The list of entities, associations, and attributes for the consumed services are shown as for the search results:
For more information on how to add entities to your app, see Adding an External Entity to an App section in External Entities.
3 Searching the Data Hub Catalog
As you enter a search term, all the items in the Data Hub Catalog satisfying the search string are listed in the search results. This includes words in the service, entity and attribute descriptions, which are not displayed in the Data Hub pane. For more information, see the Selected Asset Details section in Search in the Data Hub Catalog.
You can drag the entity from the search results into your domain model and it will be added to your app and displayed as an external entity.
3.1 Wildcard Search
You can perform a wildcard search by entering * in the search field.
The search strings must be a minimum of three alphanumeric characters. Punctuation cannot be used as part of the search term except for the wildcard character * to perform an “empty” search in the Data Hub Catalog. You cannot use the wildcard in combination with other characters. For further details, see How to Search for Registered Assets.
3.2 Filtering Environments
By default, the search is performed on assets in the Production environment. To include all other environments such as test, acceptance, and also the Mendix free app environment, Sandbox in the search, click the Filter icon and check Show development environments:
When the Show development environments is checked, all subsequent searches results will also include those in non-production environments.
4 Data Hub Pane Information
The information that is displayed in the Data Hub pane either when you enter a search term or when you open the Used in your App section is described in the sections below.
4.1 Services
The search results and User in your App section show the following information at a service level:
Service name
Application icon for the service (for example, Mendix, SAP, Siemens Teamcenter, or custom icons)
Service version
Environment name for non-production environments
Only the names of non-production environments are displayed. Services in the Production do not show an environment name.Green check-mark if the service or entity is consumed in the app. If you right-click a consumed service, you can do the following:
- View in Data Hub Catalog – click this to go to the Data Source Details page in the Data Hub Catalog
Go to connection settings – click this to open the consumed OData service document
Gray shield icon shows if the service or entity is validated in the Catalog
Update icon is a blue arrow icon that indicates that there is another version of the consumed service available in the Data Hub. Click to update the service that is consumed in the app to the contract that is now available:
If there is an OData service update available, then the entities that are listed are those that are available in that version of the OData service. These entities are grayed-out to indicate that they cannot be dragged into the domain model, as the current contract that is consumed in the app does not have these entities. You must update the contract to the version shown in the search results by clicking the Update icon.The version number that is shown for the OData service is the latest one that is available in the Data Hub Catalog at the service endpoint – in the example above, version 1.0.0 of BikeVehicleService is currently consumed in the app, but the contract that is available in the Catalog is different to the one currently consumed.Information icon allows you to view further details for the service and a link to go directly to the Service Details screen in the Data Hub Catalog:
4.2 Entities, Attributes, and Associations
Entities, attributes, and associations are displayed under the service name.
For any service in the list, you can click Show details to see the full list of the exposed entities, associations, and attributes for that service.
4.2.1 Entity
If you right-click an entity and select View in Data Hub Catalog, it will take you to the entity details page in the Data Hub Catalog.
If you right-click a consumed entity and Go to entity, it will take you to the entity in the domain model.
4.2.2 Associations
The associations that are exposed in the services are listed before attributes in alphabetical order. You can click on the + to see the entity that the association is with.
Mulitiple associations between the same entities are shown before single associations.
In the following example the entity Customer has multiple associations with the entity Order however, these associations are not supported and cannot be used in your app:
4.2.3 Attributes
Attributes for a service are listed in alphabetical order. If you right-click an attribute of a consumed entity and Go to attribute, it takes you to the attribute in the domain model.
Unsupported attributes are grayed out and are not included in your app.
4.2.4 CRUD Capabilities
If the entity, association, or attribute supports Create, Read, Update, or Delete capabilities and it is also supported by Studio Pro, then it is displayed in the Data Hub pane. Entities and associations can have any of the CRUD capabilities, while attributes can only have create and update. For more information on CRUD capabilities, see Write Data to Another App.