Providing Simulated Production Data via REST Triggers

This example shows how even a small RESTful web service with Bearer token authentication can be provided within the OPC Router itself. The web service provides simulated production data from a machine. The values are generated within the connection using formula and calculator transfer objects.

Target Configuration

The example consists of two separate connections within the same REST Server plug-in. These two workflows are created one after the other and then put into production:

1. A connection with a REST trigger using the POST method provides a token endpoint.
2. A second connection with a REST trigger using the GET method delivers the actual production data.

The typical process is as follows:

1. A client calls the endpoint for the token request using POST.
2. The OPC Router verifies client_id and client_secret.
3. The OPC Router returns a bearer token as a JSON response.
4. The client then calls the data endpoint via GET and passes the bearer token in the Authorization header.
5. The OPC Router checks the header and returns the simulated production data.

Initial Situation

For this example, we assume a single machine, PRESS-01. The data endpoint is intended to provide the following values, for example:

• Current count
• Scrap quantity
• OEE value
• Machine status
• Timestamp of the last update

In this example, the values do not come from a third-party system but are generated in the OPC Router using formula and calculator transfer objects. This keeps the example self-contained and allows it to be understood without an additional data source.

Example Calls

Token Query

POST http://localhost:50117/api/auth/token
Content-Type: application/json

{
  "client_id": "demo-client",
  "client_secret": "demo-secret"
}

A possible response looks like this:

{
  "access_token": "opcrouter-demo-token",
  "token_type": "Bearer",
  "expires_in": 3600
}

Value Query

GET http://localhost:50117/api/production-data
Authorization: Bearer opcrouter-demo-token
Accept: application/json

A possible response looks like this:

{
  "machine_id": "PRESS-01",
  "quantity": 524,
  "scrap": 11,
  "oee": 0.82,
  "state": "Production",
  "timestamp": "2026-05-11T14:30:00Z"
}

Setup in the OPC Router

REST Server Plug-in

First, create a REST server plug-in that provides both endpoints. For example, use the route prefix api.

The basic functionality of the REST server and the REST trigger is described in the respective reference pages.

REST Trigger for the Token Query

Set up your first standalone connection using a REST trigger for the token query.

1. Use auth/token, for example, as the endpoint.
2. Select POST as the HTTP method.
3. Select application/json as the response format.
4. Create a request parameter for the request body.
5. Create a response parameter for the response body.

Then read the request body using a JSON-read transfer object and extract at least the client_id and client_secret fields.

Then, use a formula and calculator transfer object to verify that the two values match the expected demo credentials, such as demo-client and demo-secret.

If the values are valid, use a JSON write transfer object to generate the token response. For a self-contained example, a fixed token value such as opcrouter-demo-token is sufficient.

A possible JSON structure for the response is:

{
  "access_token": "opcrouter-demo-token",
  "token_type": "Bearer",
  "expires_in": 3600
}

Link the generated JSON content to the response body of the REST trigger.

Then put this connection into production before testing or putting the second connection into production.

REST Trigger for the Value Query

Next, configure a second, standalone connection with a REST trigger for the actual data query.

1. Use production-data as the endpoint, for example.
2. Select GET as the HTTP method.
3. Select application/json as the response format.
4. Create a request parameter of type HTTP Header.
5. Use Authorization as the header name.
6. Create a response parameter for the response body.

Then verify that the header content matches the expected value Bearer opcrouter-demo-token.

Next, generate the production data using formula and calculator transfer objects. For a simple demo scenario, you can use constant or slightly varied values, for example:

• quantity = 524
• scrap = 11
• oee = 0.82
• state = Production

Then, use a JSON Write transfer object to combine these values into a JSON response and connect the result to the response body of the REST trigger.

One possible JSON structure is:

{
  "machine_id": "PRESS-01",
  "quantity": 524,
  "scrap": 11,
  "oee": 0.82,
  "state": "Production",
  "timestamp": "2026-05-11T14:30:00Z"
}

Next, put this second connection into production as well.

Recommended Project Structure

For a well-organized demo project, the following structure is recommended:

1. Connection Token Query with a REST trigger, JSON read, formula and calculator transfer objects, and a JSON write transfer object.
2. Production Data connection with a REST trigger, formula and calculator transfer objects for value generation, and a JSON write transfer object.
3. Optionally, one or more variables if intermediate results need to be stored separately or reused.

Switch to Production

Since this example consists of two separate connections, both connections must be explicitly switched to production after configuration. A general description of this process can be found on the [Create Connection] page (../../../../faq/connection_projecting/connection_projecting_create_connection.md). The section on the pop-up menu there also describes the Activate Connection button.

For this example, the following sequence is recommended:

1. Create the Token Query connection and put it into production.
2. Test the token endpoint using POST.
3. Create the Production Data connection and put it into production.
4. Test the data endpoint using GET with the bearer token.

Sample Project for Import

The complete sample project is available as rest_bearer_token_and_production_data_example.rpe.

The project file contains the two REST trigger connections described here, as well as the two connections from the Connection with Bearer Token example.

Import this project file into the OPC Router to fully understand the example and test it right away.