Initial setup Standup a Moodle instance using the tracker. Go to the moodle directory or the root directory where your moodle code lives. Download all the uploaded php scripts named mockbin from the tracker and save them in the root directory. Basic request Run the simple_test_mockbin.php script using the following command: php simple_test_mockbin,php Confirm that the script ran without any error Confirm that the output contains the following information: Connection #0 to host mockbin.com left intact Run the simple_test_2_mockbin.php script using the following command: php simple_test_2_mockbin,php Confirm that the script ran without any error Confirm that the output contains the following information: Connection #0 to host mockbin.com left intact Cached request Run the cache_test_mockbin.php script using the following command: php cache_test_mockbin.php Confirm that the script ran without any error Confirm that the output contains the following information: Connection #0 to host mockbin.com left intact Go to your moodledata directory (Check the config.php in your root directory to confirm the moodledata directory location) Go to cache/core_guzzle directory in your moodledata directory Confirm there is a file with a filename starting with u0_ Run the following command to check the file: cat u0_name_of_the_file Confirm that you can see the content of the file Confirm that the content of the file contains the following information: "url": "http://mockbin.com/request" Cookiejar request Run the cookiejar_test_mockbin.php script using the following command: php cookiejar_test_mockbin,php Confirm that the script ran without any error Confirm that the output contains the following information: {   "cookies": {     "other_cookie": "barbaz1234",      "some_cookie": "foo"   } } Confirm that the output contains the information about the domain: Cookie domain: mockbin.com Continuous requests Run the basictestguzzle_mockbin.php script using the following command: php basictestguzzle_mockbin,php Confirm that the script ran without any error Confirm that all the outputs are available in the console. Calendar test Open calendar/lib.php file. Replace the function calendar_get_icalendar with this function content. Login as admin. Click on User profile menu -> Calendar. Click on Import or export calendars link. Click on Import calendar button. Set the Calendar name to: Test ICS with Guzzle. Set the  Calendar URL to: https://www.officeholidays.com/ics/vietnam Click Import calendar button. Verify that the import process is success. Navigate back to the Calendar. Verify that you will see the new imported events. Remember to revert all the changes for calendar/lib.php file.