Setting up the Power Automate connection: steps in i-Reserve and Power Automate

The Power Automate connection works via a custom connector that you import into Power Automate from i-Reserve's OpenAPI definition. Configuration happens on two sides: first you set up access in i-Reserve (an OAuth client and a connection user) and download the definition, then you build the connector in Power Automate and establish the connection. Follow the steps in this order.

1. Start in i-Reserve: OAuth client + connection user

The connector needs credentials to be allowed to talk to i-Reserve. Arrange those first:

1. Log in as administrator and go to Configuration → System → OAuth clients.
2. Create a new client. Give it a logical, unique Client ID (for example ms_flow or power-automate).
3. Generate a strong Client secret (use a password generator, preferably 32 characters, max. 80). Note down both the client ID and the secret — you need them in step 4.
4. Go to Configuration → System → Users and create a connection user with exactly the rights your flows need (set via a user group). You will use this user to establish the connection later.

Background on OAuth clients is at Setting OAuth Clients and on authentication at Authenticate via OAuth 2.0.

2. Get the definition: download swagger.json

1. In your browser, open https://<your-environment>/api/rest/microsoft/swagger (for example https://demo.i-reserve.net/api/rest/microsoft/swagger). This page is anonymously accessible.
2. Save the content as a text file, for example swagger.json.

See also API - Microsoft - GET swagger. Note: importing via the URL does not work by default — download the file and import that.

3. In Power Automate: create a custom connector

1. Open Power Automate and go to Custom connectors (under Data).
2. Click New custom connector → Import an OpenAPI file.
3. Select the swagger.json file you just saved.
4. Give the connector a recognisable name, for example i-Reserve, and click Continue.
5. In principle you do not need to change anything in the definition.

4. Security: configure OAuth 2.0

In the connector, go to the Security tab and choose authentication type OAuth 2.0 with identity provider Generic Oauth 2. Fill in:

1. Click Create connector. Power Automate now generates the Redirect URL.
2. Copy that Redirect URL and enter it in i-Reserve on the OAuth client as the redirect_uri (Configuration → System → OAuth clients). Save.

5. Create and test the connection

1. In the connector, go to the Test tab and click New connection.
2. An i-Reserve login screen appears. Log in with the connection user from step 1 and grant permission for the requested rights (scope).
3. The connection is now established and you can test it with one of the available actions.

6. Create your first flow

1. Go to My flows → New flow → Automated cloud flow.
2. Name the flow and choose an i-Reserve trigger (or a trigger from another app, followed by an i-Reserve action).
3. Build the desired actions and map the fields. Save and test with a real event.

The connection can now be reused in all your flows.