OData and Integration Statements

Statements for managing OData services, external entities, and browsing service contracts.

Mendix supports consuming and publishing OData services. Consumed services (OData clients) connect to remote OData endpoints and make external entity types available for use in your application. Published services expose your domain model entities as OData endpoints for other applications to consume.

OData Client Statements

OData Service Statements (Published)

External Entity Statements

CREATE EXTERNAL ENTITIES

Bulk-create external entities from a consumed OData service’s cached $metadata.

mdl 1;
-- Create all entity types from the contract
CREATE EXTERNAL ENTITIES FROM Module.Service;

-- Create into a specific module
CREATE EXTERNAL ENTITIES FROM Module.Service INTO TargetModule;

-- Filter to specific entities
CREATE EXTERNAL ENTITIES FROM Module.Service ENTITIES (Customer, Order);

-- Idempotent — update existing entities
CREATE OR MODIFY EXTERNAL ENTITIES FROM Module.Service;

Each entity is named after its OData entity type, as Studio Pro names it: an entity type Part exposed as entity set Parts becomes Module.Part. The entity set is kept as the entity’s remote entity set. A re-import finds an entity by the service and entity set it maps first, so an entity that an earlier mxcli version named after the set (Module.Parts) is updated in place and keeps its name.

Complex types are flattened

The Mendix domain model has no complex types. A property typed as an OData ComplexType is imported as one attribute per leaf — the same thing Studio Pro does — named <property>_<leaf> and read over the OData path <property>/<leaf>:

The complex type may live in any Schema in the document — it is resolved by qualified name, so two namespaces may each declare a Quantity.

Three properties of a complex type are not importable. Each is reported by name and reason rather than dropped, so an import that loses something says so:

• Inherited properties. Only a complex type’s own properties are imported. Where AirportLocation derives from Location, the inherited Address is not reachable through it (CE6615) — though the same Address is imported normally through a property typed Location directly.
• Leaves Mendix cannot represent, such as Edm.GeographyPoint (CE6622).
• A complex type nested in a complex type — flattening is one level deep.

Two more consequences:

• Flattened attributes are read-only. Mendix treats an external entity that contains them as readable and deletable only, whatever the entity set’s InsertRestrictions / UpdateRestrictions say. Marking them creatable or updatable is CE6630.
• They are filterable and sortable only where their entity is — that is, on an entity backed by an entity set. On a derived or contained type they are neither. CE6630 fires in both directions here, so this follows the contract rather than a fixed answer.

Navigation properties become associations

Each navigation property whose target is also imported becomes an association. A navigation property with a Partner is one end of a bidirectional relationship, and Mendix does not accept its ends as separate associations (CE6618 “Navigation ‘…’ is not available in the OData service”):

A re-import of a module that an earlier mxcli version imported the old way lists the associations that fail with CE6618 as drop association …; lines. Run them, then run the import again.

Calling an External Action

$Response = call external action Odata.OrderService.CreateBuffer(
  command = $Cmd include associations (Odata.Quantity (Odata.Unit)),
  additional = nothing
);

include associations ( … ) after an argument is Studio Pro’s Associations to include: the associations whose objects are serialised into the OData request with that argument. It is a tree. A name followed by ( … ) lists the associations included under it, reached from the entity at its far end. Without the clause, a sub-object linked to the argument is not sent, and nothing fails until the service receives the request.

• Which end of each association the object is on is worked out from the domain model, so the clause names only the associations.
• A self-association is refused, because its direction cannot be derived. Tick it in Studio Pro instead. describe prints a tree that holds one as a comment.
• include associations () removes them all. To remove some, restate the tree without them. The clause is always the whole tree.
• Left out on create or modify, the stored tree is kept, and check -p and exec warn with MDL-ODATA10. Deleting the clause does not remove the associations.
• describe microflow prints the clause, so describe → exec restates the tree.
• A non-empty clause needs Mendix 10.11 or later.

Contract Browsing Statements

Browse available assets from cached service contracts without network access.

Related Show/Describe Statements

Catalog Tables

After REFRESH CATALOG, the following tables are available for SQL queries:

Example: Find available entities not yet imported

SELECT ce.EntityName, ce.ServiceQualifiedName, ce.PropertyCount
FROM CATALOG.CONTRACT_ENTITIES ce
LEFT JOIN CATALOG.EXTERNAL_ENTITIES ee
  ON ce.ServiceQualifiedName = ee.ServiceName
  AND ce.EntityName = ee.RemoteName
WHERE ee.Id IS NULL;