This sprint, we managed to get multiple changes merged into our team’s offline-login branch. Luigi and I worked on coding the back end of the checkbox with George’s help. In the authentication service, Luigi created two new methods, authenticateAndSave and setAndSaveCredentials. These mirror the authenticate method and the setCredentials method respectively, each with an added boolean parameter. We decided this would be simpler than trying to restructure the existing methods to accept a boolean value they would only use sometimes. The authenticateAndSave method saves the boolean value in the saveOfflineCreds variable and then passes other duties to the authenticate method, and setAndSaveCredentials stores the user in localStorage and then passes other duties to the setCredentials method.
For my part, I tried to modify the login component to utilize authenticateAndSave instead of authenticate when the checkbox is checked. Attempting to make this change produced a lot of unexpected difficulties. Using the HTML checkbox’s id attribute, I declared a variable to perform the .checked method on, which defaulted to the type HTMLElement. Trying to call .checked on this object didn’t work, so I tried to cast it to an HTMLInputElement, the type that has this method, in the declaration. When this wasn’t allowed by the TSLint file, I used “as” syntax type assertion. This was accepted without compiler errors, and I could call .checked on the HTMLInputElement object, but we found later that the code testing whether the checkbox is checked broke the ability to log in. When you click the login button, the login method gets to the conditional statement that checks whether the checkbox is checked and can’t go past it, giving a type error that says “Cannot read property ‘checked’ of null.” We weren’t able to fix this by the end of this sprint, but we plan on it being the final change we make before the semester ends. Once we can verify that the authenticateAndSave method is called correctly, the back end will be complete and users will have the option to store their credentials for offline use later.
Members of our team also made edits to the online tracker component, wrote tests for the checkbox functionality, and documented the progress we’ve made so far so that whoever continues the work after us can better understand our choices.
I thought our teamwork was excellent this sprint too. George identified to Luigi and I the parts of the code he’d written which in conjunction stored the user credentials in localStorage. Luigi and I were able to complete separate parts of the checkbox back end task and then integrate them.