Fetching token to embed an application

Some of apps provided by Placewise are available for embeding using dedicated token. These apps work in context of authorized member.

Available apps

App	Resource
Receipt Scanner	`placewise.com/component/web_form`
Rewards	`placewise.com/component/web_form`
Games (all)	`placewise.com/component/games_api`

In order to receive token, client must execute Token Exchange with standard application/x-www-form-urlencoded content type and following params:

Param	Value
client_id	ID of client
client_secret	Client's secret (if client is confidential)
grant_type	`urn:ietf:params:oauth:grant-type:token-exchange`
subject_token_type	`urn:ietf:params:oauth:token-type:access_token`
subject_token	Member's access token
scope	`openid`
resource	Correct resource (for example `placewise.com/component/web_form`)