write assignment10 prerequisites

[zoe-1]

Assignment code located: relevant documentation test/api/user.js lib/api/prerequisites lib/api/user.js

• [x] write the assignment text.

• [ ] make final edits to assignment text

• [ ] create a file for the assignment in assignments folder. Place the below write up in that file.

[zoe-1]

Assignment10 - prerequisites

After completing assignment9, we have a general understanding of the request lifecycle and how to extend it. In this assignment, we will build on that knowledge and extend the request lifecycle for the /login route using prerequisites. The objective will be to tidy up the /login route handler.

Assigment9's /login route handler in ./lib/api/user.js contains all authentication and session generation logic. This makes the handler a bit cluttered. To clean things up, we move the authentication and session generation logic out of handler into two prerequisite functions: getUser() & createSession(). See prerequisite functions here.

Prerequisite functions are executed right before the handler in the request lifecycle. We will use prerequisites to move complex logic from the handler to the prerequisite functions. Assignment requirements below:

• Build the two prerequisite functions in lib/api/prerequisites.js . They will execute authentication and session generation logic previously performed in the handler.
• Refactor /login route in lib/api/user.js to use the two prerequisites made in the previous step.
• Refactor tests for 100% coverage: test/api/user.js
• refactor internals.getUser() To make ./lib/api/user.js more readable, move the internals.getUser() into it's own file
  ./lib/api/extensions.js. Then, change ./lib/api/user.js to include the file and edit the /login route object's ext to use the function included from ./lib/api/extensions.js. This makes ./lib/api/user.jsonly contain route objects versus being cluttered with functions used to prepared data for the handles.

At completion of assignment10 when we read our /login route we see:

• the (onPreResponse) extension in the route object (assignment9). assignment10 moved the extension method to it's own file.
• the two prerequisite functions to be executed before the handler (assignment10),
• validation logic applied to the payload received by the route (assignment7)
• and the handler itself.

It is an extremely readable route object. One look gives a nice overview of everything going on in the route. The conciseness and readability show off the beauty of the hapi request lifecycle design pattern. And, the elegance motivates us to use hapi to write clean and maintainable code.

Review:

Take sometime and look over the request lifecycle document. Then, find each element in the /login route object which relates to the request lifecycle for this route. Locate where in the lifecycle each element will be executed. The goal is to understand how the route object can be configured to execute methods at different stages in the lifecycle.

focus on:

• extensions ext
• prerequisites pre
• validation validate
• handler
• authentication auth