Sending content urls back to consumer beyound express or from the client

[codeduo]

#I'm new to LTIs and have an implementation question and hope I can find some direction here.

I'm using meteor, express (to handle POST request) and React(client)/React Router, and experimenting with an LTI that allows instructors to send a URL link of some search result content back to the course page, after launching the LTI from the editor button.

After clicking on the editor button, in canvas, on the server backend, I have successfully been able to take the express's req and res objects and create a valid LTI provider, after validating the post request within a middleware function, where I have access to the request object.

Next, my search app comes up, and at this point, I would like to send a URL hyperlink back to be included in the course content. The only thing is, I only know how to do that on the server using:

provider.ext_content.send_url(res, hyperlink_url, text, title_attribute, target_attribute)

because it seems like it's the only place I can create the lti.provider is within Express, where I have access to the res and req.

Is there a way to send the consumer a URL link using the
provider.ext_content.send_url(res, hyperlink_url, text, title_attribute, target_attribute) outside of express, particularly from the client?

Any help is welcomed, thank you.