Using Adobe Sign API

Hi,

I'd like to experiment with Coldfusion and Adobe Sign. It uses OAuth.

Some info: https://secure.au1.adobesign.com/public/static/oauthDoc.jsp

Example:

<cfhttp result="result" method="GET" charset="utf-8" url="https://secure.na1.adobesign.com/public/oauth/v2">
<cfhttpparam
type="FORMFIELD"
name="response_type"
value='code'
/>
<cfhttpparam
type="FORMFIELD"
name="client_id"
value='my client id is omitted.'
/>
<cfhttpparam
type="FORMFIELD"
name="redirect_uri"
value="https://localhost/testsign/redirect.cfm"
/>
<cfhttpparam
type="FORMFIELD"
name="scope"
value='user_read:account+user_write:account+user_login:account+agreement_read:account+agreement_write:account+agreement_send:account+widget_read:account+widget_write:account+library_read:account+library_write:account+workflow_read:account+workflow_write:account'
/>
<cfhttpparam
type="FORMFIELD"
name="state"
value='1234'
/>
</cfhttp>

If I cfdump the result the Status code is 200 OK

It has has a Filecontent var containing html. If I paste this html into a page to view it, I can see that there is an error text "Unable to authorize access because the client configuration is invalid: invalid_request"

The expected outcome would be the page should redirect to the URL https://localhost/testsign/redirect.cfm

This does not occur. The cfhttp.FileContent var does hold html.

I have enabled http on localhost.

I don't know what the issue is.

Information about Adobe Sign is pretty scarce. Maybe I am doing something obviously incorrect?

Any thoughts?