# Message flow examples

This are some examples how a message flows in the Open Smart Grid Platform.

## Message Flow: Request/Acknowledge/Poll

![Request/Acknowledge/Poll](https://824268196-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2F-Mf3CXew4gGGjSc82zik%2Fuploads%2Fgit-blob-7df537cb26b34dbe44ed9a7e58ef168aa43ff9b9%2FMessageflow-1-poll.png?alt=media)

| **Step** | **Description**                                                                                                       |
| -------- | --------------------------------------------------------------------------------------------------------------------- |
| 1        | WS adapter receives client soap request with organization certificate and organization id in soap header              |
| 2        | WS adapter authenticates organization, checks authorizations and sends request message to domain adapter (via queue)  |
| 3        | WS adapter returns soap acknowledgement with correlation id                                                           |
| 4        | Domain adapter sends request message to core (via queue)                                                              |
| 5        | Core determines protocol for device and sends request message to protocol adapter (via queue)                         |
| 6        | Protocol adapter translates domain request message, sends request to device and receives response from device         |
| 7        | Protocol adapter sends response message to core (via queue)                                                           |
| 8        | Core forwards response message to domain adapter (via queue)                                                          |
| 9        | Domain adapter forwards response message to response queue                                                            |
| 10       | Client app polls for response using correlation id (with organization certificate and organization id in soap header) |
| 11       | WS adapter retrieves response message from response queue                                                             |
| 12       | WS adapter sends soap response to client app                                                                          |

## Message Flow: Request/Acknowledge/Notify

![Request/Acknowledge/Notify](https://824268196-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2F-Mf3CXew4gGGjSc82zik%2Fuploads%2Fgit-blob-1f5bb7932760539b03a66554c9e555dd54e7f046%2FMessageflow-2-Notify.png?alt=media)

| **Step** | **Description**                                                            |
| -------- | -------------------------------------------------------------------------- |
| 1-8      | Same as request/acknowledge/poll message flow                              |
| 9        | Domain adapter forwards response message to WS adapter                     |
| 10       | WS adapter stores response in DB                                           |
| 11       | WS adapter sends soap notification with correlation id to the client app\* |
| 12       | Client app sends soap request with correlation id to retrieve the response |
| 13       | WS adapter retrieves (and deletes) response from DB                        |
| 14       | WS adapter sends soap response to the client app                           |

\*In case the response is not timely retrieved by the client app, OSGP will resend the notification with correlation id to the client app. The amount of retries is configurable.