OData Meta Model
The implementation sap.ui.model.odata.ODataMetaModel offers a unified access to both OData Version 2.0 metadata and Version 4.0 annotations.
It uses the existing sap.ui.model.odata.ODataMetadata as a foundation and merges the OData Version 4.0 annotations from the existing sap.ui.model.odata.ODataAnnotations directly into the corresponding entity or property.
You can get an instance of sap.ui.model.odata.ODataMetaModel from an instance of sap.ui.model.odata.v2.ODataModel, see XML Templating in SAPUI5.
The basic structure of sap.ui.model.odata.ODataMetadata is shown in the following code snippet. It shows you how the most important elements of the entity model are nested. Each of these elements (except association set end) can have extensions, that is, XML attribute values from some namespace. The code snippets below show how these extensions are stored and processed.
{
"dataServices": {
"schema": [{
"association": [{
"end": []
}],
"complexType": [{
"property": []
}],
"entityContainer": [{
"associationSet": [{
"end": []
}],
"entitySet": [],
"functionImport": [{
"parameter": []
}]
}],
"entityType": [{
"property": [],
"navigationProperty": []
}]
}]
}
}The following code snippet gives a closer look and has more properties:
{
"version": "1.0",
"dataServices": {
"dataServiceVersion": "2.0",
"schema": [{
"namespace": "GWSAMPLE_BASIC",
"entityType": [{
"name": "BusinessPartner",
"key": {
"propertyRef": [{
"name": "BusinessPartnerID"
}]
},
"property": [{
"name": "BusinessPartnerID",
"type": "Edm.String",
"nullable": "false",
"maxLength": "10"
}],
"navigationProperty": [{
"name": "ToSalesOrders",
"relationship": "GWSAMPLE_BASIC.Assoc_BusinessPartner_SalesOrders",
"fromRole": "FromRole_Assoc_BusinessPartner_SalesOrders",
"toRole": "ToRole_Assoc_BusinessPartner_SalesOrders"
}]
}],
"complexType": [{
"name": "CT_Address",
"property": [{
"name": "City",
"type": "Edm.String",
"maxLength": "40"
}]
}],
"association": [{
"name": "Assoc_BusinessPartner_SalesOrders",
"end": [{
"type": "GWSAMPLE_BASIC.BusinessPartner",
"multiplicity": "1",
"role": "FromRole_Assoc_BusinessPartner_SalesOrders"
}, {
"type": "GWSAMPLE_BASIC.SalesOrder",
"multiplicity": "*",
"role": "ToRole_Assoc_BusinessPartner_SalesOrders"
}],
"referentialConstraint": {
"principal": {
"role": "FromRole_Assoc_BusinessPartner_SalesOrders",
"propertyRef": [{
"name": "BusinessPartnerID"
}]
},
"dependent": {
"role": "ToRole_Assoc_BusinessPartner_SalesOrders",
"propertyRef": [{
"name": "CustomerID"
}]
}
}
}],
"entityContainer": [{
"name": "GWSAMPLE_BASIC_Entities",
"isDefaultEntityContainer": "true",
"entitySet": [{
"name": "BusinessPartnerSet",
"entityType": "GWSAMPLE_BASIC.BusinessPartner"
}],
"associationSet": [{
"name": "Assoc_BusinessPartner_SalesOrders_AssocS",
"association": "GWSAMPLE_BASIC.Assoc_BusinessPartner_SalesOrders",
"end": [{
"entitySet": "BusinessPartnerSet",
"role": "FromRole_Assoc_BusinessPartner_SalesOrders"
}, {
"entitySet": "SalesOrderSet",
"role": "ToRole_Assoc_BusinessPartner_SalesOrders"
}]
}],
"functionImport": [{
"name": "SalesOrder_Confirm",
"returnType": "GWSAMPLE_BASIC.SalesOrder",
"entitySet": "SalesOrderSet",
"httpMethod": "POST",
"parameter": [{
"name": "SalesOrderID",
"type": "Edm.String",
"mode": "In",
"maxLength": "10"
}]
}]
}]
}]
}}Extensions are stored as an array of objects, each with a namespace, a name, and a value. Annotations from the "http://www.sap.com/Protocols/SAPData" namespace are lifted up from the extensions array and transformed from objects into simple properties with an sap: prefix added to their name, see line number 8 in the following code snippet.
As this happens in addition, the following example shows both representations. By this, the respective annotations can be addressed via a simple relative path instead of searching an array.
1 {
2 "name": "BusinessPartnerID",
3 "extensions": [{
4 "name": "label",
5 "value": "Bus. Part. ID",
6 "namespace": "http://www.sap.com/Protocols/SAPData"
7 }],
8 "sap:label": "Bus. Part. ID"
9 }Each element of the entity model (except association set end) can be annotated. These annotations from the existing sap.ui.model.odata.ODataAnnotations are merged directly into the corresponding element. The following code snippet shows how the structure from the existing sap.ui.model.odata.ODataMetadata, as explained above and including extensions and constraints such as nullable or maxLength, is fleshed out with lifted v2 annotations and inlined v4 annotations, such as Org.OData.Measures.V1.Unit or com.sap.vocabularies.UI.v1.Identification. If you want to navigate the structure, for example for XML templating, it is important to understand this structure.
ODataMetaModel JSON Format:
"dataServices" : {
"schema" : [{
"namespace" : "GWSAMPLE_BASIC",
"entityType" : [{
"name" : "Product",
"property" : [{
"name" : "ProductID",
"type" : "Edm.String",
"nullable" : "false",
"maxLength" : "10"
}, {
"name" : "SupplierName",
"type" : "Edm.String",
"maxLength" : "80",
"extensions" : [{
"name" : "label",
"value" : "Company Name",
"namespace" : "http://www.sap.com/Protocols/SAPData"
}, {
"name" : "creatable",
"value" : "false",
"namespace" : "http://www.sap.com/Protocols/SAPData"
}, {
"name" : "updatable",
"value" : "false",
"namespace" : "http://www.sap.com/Protocols/SAPData"
}],
"sap:label" : "Company Name",
"sap:creatable" : "false",
"sap:updatable" : "false"
}, {
"name" : "WeightMeasure",
"type" : "Edm.Decimal",
"precision" : "13",
"scale" : "3",
"Org.OData.Measures.V1.Unit" : {
"Path" : "WeightUnit"
}
}, {
"name" : "WeightUnit",
"type" : "Edm.String",
"maxLength" : "3"
}],
"com.sap.vocabularies.UI.v1.DataPoint" : {
"Value" : {
"Path" : "WeightMeasure",
"EdmType" : "Edm.Decimal"
}
},
"com.sap.vocabularies.UI.v1.Identification" : [{
"Value" : {"Path" : "ProductID"}
}, {
"Value" : {"Path" : "SupplierName"}
}, {
"Value" : {"Path" : "WeightMeasure"}
}]
}]
}]
}