Enterprise Connect

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Enterprise Connect is an alternative way for applications to obtain authorization to access users’ calendars. Instead of each end-user giving authorization individually, a Service Account is used to obtain authorization programmatically.

The flow to obtain authorization on an organization level looks like this:

Service Account authorization flow

Step by step

The customer’s IT admin creates a Service Account on their calendar service, configured with the permissions and restrictions they want.
Your application sends the IT admin to Cronofy’s hosted authorization page, specifying the permissions it needs on their organization’s calendars as the scope.
The IT admin logs in to the calendar service as the Service Account and approves access.
The calendar service grants Cronofy access through the Service Account.
Cronofy redirects the IT admin back to your application with a code on the query string.
Your application redeems the code with Cronofy.
Cronofy returns an access_token, a refresh_token and a service_account_id to your application.
Your application stores the Service Account’s tokens. It uses the access_token to request delegated access to the calendars of users and resources in the organization.

Diagram source

sequenceDiagram
  autonumber
  participant Your Application
  participant Cronofy
  actor IT admin
  participant Calendar service

  IT admin->>Calendar service: Create a Service Account with permissions
  Your Application->>Cronofy: Send IT admin to authorization page with scope
  IT admin->>Calendar service: Log in as the Service Account and approve
  Calendar service->>Cronofy: Access granted
  Cronofy->>Your Application: Redirect IT admin back with code
  Your Application->>Cronofy: Redeem code
  Cronofy-->>Your Application: access_token, refresh_token and service_account_id
  Your Application->>Your Application: Store Service Account tokens

The authorization process #

To get started, you will need the following:

A web application
A client_id and client_secret for your application from the Cronofy Developer Dashboard
A Service Account on a Google Workspace, Microsoft 365, or On-premise Exchange installation configured to access one or more user mailboxes.

Once you have these you are then in a position to proceed with the first stage of authorization which is for the Service Account. More details below but this process is modelled as an OAuth2 flow. You redirect from your application to an authorization page and which in return redirects back to your application with a code for subsequent access_token redemption.

Once you have an access_token for a Service Account you then use that to request individual access_tokens for user and resource calendars. You then store and use the access_tokens in exactly the same way with the Cronofy API as you do with those generated through direct end-user authorization.

Service Accounts #

Service Accounts are organization level accounts that can be created in both Microsoft and Google Workspace domains. They can be granted permissions on a set of mailboxes within the domain. They can also be given permissions to access Resource Calendars (eg meeting rooms) and Shared Mailboxes.

A Service Account can be used to:

Request Delegated Access to user’s calendars, resource calendar or shared mailbox calendar.
List Resource calendars available to the Service Account.

It can’t be used to access calendars or events of its own.

The Enterprise Connect - Guide for System Administrators gives more information on how to setup and configure Service Accounts.

Service Account authorization #

As described above, obtaining an authorization for a Service Account is modelled as an OAuth2 flow. The outcome of this flow is an access_token for the Service Account.

The documentation describes the full set of parameters but of particular note are scope and delegated_scope .

scope refers to the permissions you are requesting that directly apply to the Service Account. For instance if you want access to User mailboxes you would request service_account/accounts/manage and if you also want Resource Calendars then you would add service_account/resources/manage . These are presented as a space separated list.

delegated_scope refers to the maximum set of possible permissions your application will need for the User and Resource calendars. These are similar to the scope values you would request as part of direct end-user authorization.

User and resource calendar account authorization #

Once you have a Service Account authorization, you can then request access to an individual User or Resource Calendar. This is similar to an OAuth flow but without user involvement.

The diagram below shows how you can obtain a code for a user or resource, which can then be exchanged for an access_token, which is used to authenticate user-specifc or resource-specific requests to the Cronofy API.

Delegated access flow

Step by step

Your application requests delegated access from Cronofy, authenticated with the Service Account’s access_token, giving the user or resource’s email, the permissions it needs as the scope, and a callback_url. This begins the steps repeated for each user or resource.
Cronofy sends a code to the callback_url.
Your application redeems the code with Cronofy.
Cronofy returns an access_token, a refresh_token and a sub value to your application.
Your application stores the tokens. It uses the access_token to access the user or resource’s calendar, and the refresh_token to get a new access_token when one expires. This ends the repeated steps.

Diagram source

sequenceDiagram
  autonumber
  participant Your Application
  participant Cronofy

  loop For each user or resource
    Your Application->>Cronofy: Request delegated access with email, scope and callback_url
    Cronofy->>Your Application: Send code to callback_url
    Your Application->>Cronofy: Redeem code
    Cronofy-->>Your Application: access_token, refresh_token and sub
    Your Application->>Your Application: Store tokens
  end

A request for Delegated Access is made which has similar parameters to an OAuth2 authorization. The redirect_uri is replaced by a callback_url.

The callback_url will need to be publicly accessible so during development we recommend using a service like ngrok.

The code is returned to this callback_url and an Access Token Request is made with the code.

Again, replace redirect_uri with callback_url.

{
  "client_id": "{CLIENT_ID}",
  "client_secret": "{CLIENT_SECRET}",
  "grant_type": "authorization_code",
  "code": "{CODE}",
  "callback_url": "{CALLBACK_URL}"
}

You can then store the access_token and refresh_token returned against the user in your application.

Refreshing access tokens obtained through Enterprise Connect #

This is identical to the process for tokens generated by end-user authorization. Refresh an Access Token.

Using access tokens obtained through Enterprise Connect #

We’ve designed the Enterprise Connect process to ensure you can use the tokens generated with the Cronofy API in exactly the same way as those generated by end-user authorization.

Revoking user authorization #

When a user wants to terminate their service, you will need to revoke the authorization between their account and your application.

This can be done by calling the Revoke Authorization API endpoint.

Supported platforms #

Enterprise Connect currently supports the following platforms: