Demo project from Lukyanau Mikhail to let you understand how you can create OData service from scratch upon of your data model without using additional frameworks as CDS+RAP or CDS+BOPF.
Also this project has a good documentation in SAP community where author is explaided full path of creating OData service from scratch by using Eclipse + ADT + adjusted SAP GUI accessible from Eclipse by Alt+F8.
clone this project to your SAP instance by using abapGIT to previously created package ZMLODATA
After activating your package should look like this one:
Double press on GW Service Builder Project ZML_TRAVELLING_ODT to open project by SEGW transaction:
In project ZML_TRAVELLING_ODT open the node Service maintenance and choose accessible SAP Gateway and press button +Register to make registration of service:
Once service is registerd you can use button SAP Gateway Client to open HTTP client and do requests to this service.
To work with JSON format adjust request Header by adding these parameters:
| Header parameter | value | when to use: |
|---|---|---|
| accept | applicaiton/json | GET, POST |
| content-type | applicaiton/json | GET, POST |
| if-match | * | PUT,PATCH,DELETE |
Example of executing method GET by URI: /sap/opu/odata/sap/ZML_TRAVELLING_ODT_SRV/ZML_ITRAVELSet?$expand=TO_BOOKING
Example of executing method POST with structure for deep insert:
URI: /sap/opu/odata/sap/ZML_TRAVELLING_ODT_SRV/ZML_ITRAVELSet
Table of all possible for this service CRUD operations:
| Name operation | Method | Header parameters | Body of request | URI |
|---|---|---|---|---|
| Read Travels | GET | accept:applicaiton/json content-type:applicaiton/json | - | /sap/opu/odata/sap/ZML_TRAVELLING_ODT_SRV/ZML_ITRAVELSet |
| Read Travels with Bookings | GET | accept:applicaiton/json content-type:applicaiton/json | - | /sap/opu/odata/sap/ZML_TRAVELLING_ODT_SRV/ZML_ITRAVELSet?$expand=BOOKING_TO |
| Read Bookings | GET | accept:applicaiton/json content-type:applicaiton/json | - | /sap/opu/odata/sap/ZML_TRAVELLING_ODT_SRV/ZML_IBOOKINGSet |
| Create Travel and Bookings | POST | accept:applicaiton/json content-type:applicaiton/json | { "Name": "Test travel 1", TO_BOOKING: [ { "Hotel": "Test Hotel", "Dayfrom" : "/Date(1481760000000)/", "Dayto" : "/Date(1481760000000)/" } ] } | /sap/opu/odata/sap/ZML_TRAVELLING_ODT_SRV/ZML_ITRAVELSet |
| Create Booking ( you should know TravelId ) | POST | accept:applicaiton/json content-type:applicaiton/json | { "TravelId" : "0242ac11-0002-1eef-80aa-0315685dd657", "Hotel": "Test Hotel", "Dayfrom" : "/Date(1481760000000)/", "Dayto" : "/Date(1481760000000)/" } | /sap/opu/odata/sap/ZML_TRAVELLING_ODT_SRV/ZML_IBOOKINGSet |
| Replace Travel record (you should know TravelId) | PUT | accept:applicaiton/json content-type:applicaiton/json if-match:* | { "Client": "001", "Name": "Test travel 1"} | /sap/opu/odata/sap/ZML_TRAVELLING_ODT_SRV/ZML_ITRAVELSet(guid('"0242ac11-0002-1eef-80aa-0315685dd657"')) |
| Change Travel record (you should know TravelId) | PATCH | accept:applicaiton/json content-type:applicaiton/json if-match:* | { "Client": "001", "Name": "Test travel 1"} | /sap/opu/odata/sap/ZML_TRAVELLING_ODT_SRV/ZML_ITRAVELSet(guid('"0242ac11-0002-1eef-80aa-0315685dd657"') |
| Replace Booking record (you should know BookingId) | PUT | accept:applicaiton/json content-type:applicaiton/json if-match:* | { "TravelId" : "0242ac11-0002-1eef-80aa-0315685dd657", "Hotel": "Test Hotel", "Dayfrom" : "/Date(1481760000000)/", "Dayto" : "/Date(1481760000000)/" } | /sap/opu/odata/sap/ZML_TRAVELLING_ODT_SRV/ZML_IBOOKINGSet(guid('"0242ac11-0002-1eef-80aa-0315685dd657"')) |
| Change Booking record (you should know BookingId) | PATCH | accept:applicaiton/json content-type:applicaiton/json if-match:* | { "Hotel": "Test Hotel" } | /sap/opu/odata/sap/ZML_TRAVELLING_ODT_SRV/ZML_IBOOKINGSet(guid('"0242ac11-0002-1eef-80aa-0315685dd657"') |
| Delete Travel record (you should know TravelId) | DELETE | accept:applicaiton/json content-type:applicaiton/json if-match:* | - | /sap/opu/odata/sap/ZML_TRAVELLING_ODT_SRV/ZML_ITRAVELSet(guid('"0242ac11-0002-1eef-80aa-0315685dd657"') |
| Delete Booking record (you should know BookingId) | DELETE | accept:applicaiton/json content-type:applicaiton/json if-match:* | - | /sap/opu/odata/sap/ZML_TRAVELLING_ODT_SRV/ZML_IBOOKINGSet(guid('"0242ac11-0002-1eef-80aa-0315685dd657"') |
Please read documentation about this on my blog in SAP community here (I recommend to copy this link and paste in browser, because redirecting from github can give you 403 forbidden error): https://community.sap.com/t5/application-development-blog-posts/creation-of-odata-service-with-implementation-of-crud-methods-and-deep/ba-p/13685666
Happy studding code and programming!
Thank you!
Yours sincirely,
Mikhail.