test: add tests for token handling

+ getAuthorizationHeader
+ tokenValid

features/adapter_get-authorization-header.feature

+Feature: Does the adapter authenticate?
+  When an adapter instance is created it authenticates and receives a token
+
+  Scenario: getAuthorizationHeader returns a bearer token
+    Given valid config
+    When the adapter instance is created
+    When the auth method is called
+    When the getAuthorizationHeader method is called
+    Then a headers object is returned containing a bearer token authorization header
+
+  Scenario: getAuthorizationHeader implicitly calls auth if required
+    Given valid config
+    When the adapter instance is created
+    When the getAuthorizationHeader method is called
+    Then a headers object is returned containing a bearer token authorization header
+
+  Scenario: getAuthorizationHeader implicitly calls auth if required
+    Given invalid config
+    When the adapter instance is created
+    When the getAuthorizationHeader method is called
+    Then an error response is returned with status 403
\ No newline at end of file

features/adapter_token-valid.feature

+Feature: Is the token valid?
+  The adapter tokenValid method works as expected
+
+  Scenario: If adapter has not authed token is invalid
+    Given valid config
+    When the adapter instance is created
+    Then tokenValid returns false  
+
+  Scenario: If credentials.expiry is in the future token is valid
+    Given valid config
+    When the adapter instance is created
+    When the auth method is called
+    When the token expiry is in the future
+    Then tokenValid returns true  
+
+  Scenario: If credentials.expiry is in the past token is invalid
+    Given valid config
+    When the adapter instance is created
+    When the auth method is called
+    When the token expiry is in the past
+    Then tokenValid returns false 

test/cucumber/adapter/broadcast.steps.js

-const assert = require('assert');
-const { When, Then } = require('@cucumber/cucumber');
+const { When } = require('@cucumber/cucumber');
 
 const { fixtures } = require('../../fixtures/server');
 

test/cucumber/adapter/get-authorization-header.steps.js

+const assert = require('assert');
+const { When, Then } = require('@cucumber/cucumber');
+
+When('the getAuthorizationHeader method is called', function() {
+  this.call = this.adapter.getAuthorizationHeader()
+});
+
+Then('a headers object is returned containing a bearer token authorization header', function() {
+  this.call.then(headers => {
+    assert.ok('Authorization' in headers);
+    const authHeaderWords = headers.Authorization.split(" ");
+    assert.ok(authHeaderWords[0] === 'Bearer');
+    assert.ok(authHeaderWords[1] === this.adapter.credentials.token);
+  });
+});
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test/cucumber/adapter/token-valid.steps.js

+const assert = require('assert');
+const { When, Then } = require('@cucumber/cucumber');
+
+When('the token expiry is in the future', function() {
+  const expiry = new Date();
+  expiry.setHours(expiry.getHours()+1);
+  this.adapter.credentials.expiry = expiry.toISOString();
+});
+
+When('the token expiry is in the past', function() {
+  const expiry = new Date();
+  expiry.setHours(expiry.getHours()-1);
+  this.adapter.credentials.expiry = expiry.toISOString();  
+});
+
+// Boolean parameters are not supported
+// and returns "true" would be misleading
+Then('tokenValid returns true', function() {
+  const isValid = this.adapter.tokenValid();
+  assert.ok(isValid);
+});
+
+Then('tokenValid returns false', function() {
+  const isValid = this.adapter.tokenValid();
+  assert.ok(!isValid);
+});
\ No newline at end of file