Scooping headers off of one Postman request and injecting them into others - rest

Question

My web service uses JWT-based authorization bearer token authentication:
HTTP clients send a valid POST to /v1/auth/signIn with a valid JSON request entity (includes username + password info)
If they authenticate successfully, that endpoint sends back an auth bearer token as an HTTP response header that (from curl) looks like:
Response from curl:
HTTP/1.1 200 OK
Date: Tue, 04 Sep 2018 01:18:28 GMT
X-Content-Type-Options: nosniff
X-XSS-Protection: 1; mode=block
Cache-Control: no-cache, no-store, max-age=0, must-revalidate
Pragma: no-cache
Expires: 0
X-Frame-Options: DENY
Access-Control-Expose-Headers: Authorization
Authorization: Bearer <big_huge_string>
Content-Length: 0
Subsequent service calls to authenticated endpoints just need to include the token as an HTTP request header whose key/name is Authorization and whose value is "Bearer <xyz>" (where <xyz>) is the <big_huge_string> that came back on the sign in call above. Pretty basic standard JWT stuff.
I'm trying to write a Postman collection that starts with a "Sign In Request" that successfully signs in and gets a JWT token from the service, and then adds the appropriate HTTP request header in each subsequent call. Any ideas as to how I can:
Extract the <big_huge_string> off the HTTP response header that I'll get back from my Sign In Request?; and then
How to save that <big_huge_string> as a variable and inject that as an HTTP request header for all subsequent calls?
Thanks in advance!
Update
Tried the suggestion:
Getting closer, but console.log(...) isn't printing anything to Postman (or at least I don't know where to look for it). I should mention I'm not using the Chrome Application version of Postman, but the standalone app/executable (Version 6.1.4):
Any ideas how/where I can get console.log(...) working? I'm concerned about just changing the test to:
pm.test("Can Extract JWT", function() {
var authHeader = pm.response.headers.toObject().Authorization;
pm.expect(authHeader).to.not.be.equal(null);
pm.globals.set('token', authHeader)
});
Without first seeing what that authHeader even is. Any ideas?!

Answer 1

Once you have that Token value you can reference it in each of the request headers using the {{token}} syntax. It's getting the sign in Auth header that's the harder part.
You could use pm.response.headers to get a list of the Headers and then extract out the value that you need.
This is returned as a list so maybe using something like Lodash or converting this to an object can help get the value you need. It would be something like pm.response.headers.toObject().Authorization - I haven't tried it so my syntax might be slightly wrong.
You can log the Headers out to the Postman console and narrow it down that way to - just wrap it in a Console.log() statement.
When you get that value, it's just a basic pm.globals.set('token, pm.response.headers.toObject().Authorization) to save this globally.