Salesforce (Custom Domain)
In case you have a custom domain Salesforce setup you cannot use the build-in Salesforce connector that the app provides. Also, if you want more control over the setup, this is a good alternative approach.
Create a new connected app
Start by creating a New Connected App
in the App Manager
.

You will need to fill in all the required fields. The Callback URL
must be set. You find the value in the data source configuration.

In this example use https://external-data-for-jira.codefortynine.com/signin-dynamic-oauth
. Also make sure to add at least the following OAuth scopes:
Access and manage your data (api)
Perform requests on you behalf at any time (refresh_token, offline_access)

Now you can save the newly created app and enter view
mode.

In this view, you can copy the Consumer Key
and the Consumer Secret
that you need to setup the data source later.

Data Source
Start setting up the data source configuration by using the URL / REST
type.
A good URL to test is https://xxx.salesforce.com/services/data/v45.0/query/?q=Select name from account
. The xxx
is your instance ID and can be found in the company information or when hovering your avatar while logged in.
Select OAuth 2
as the Authentication
method ad Authorization Code
as the Grant Type
.
Now copy the Consumer Key
into the Client ID
field and the Consumer Secret
into the Client Secret
field.
For the Auth & Token URL we are using the defaults, but these URLs may differ depending on your custom domain setup.
https://login.salesforce.com/services/oauth2/authorize
https://login.salesforce.com/services/oauth2/token
No you should be able to press Authenticate
and approve the requested permissions. If everything went well you should see a green Access Token
and Refresh Token
label at the bottom. Now you can save the data source and test the connection.

Limitations
The maximum number of rows returned by SOQL over the REST API is 2.000 per request. You can workaround this limitation by using Salesforce Pagination