Add validation messages to a login form

I have a working login form which communicates with a backend server that is able to validate the login. The project uses the angular 2 javascript framework. I need to enhance the form so that it provides validation to the login form, and error handling. Before the form is submitted. checks that the email has been entered checks that the password has at least 5 characters If any of the above checks failed to highlight the entry field and display a message below of the requirement. Then when the form is submitted and the response received (this code is working ok) there will be a status field that the back end sets if the login passed or failed against the database. If the status is > 0 then show an alert error on the login screen. (this needs to be added). The alert message comes from the returned statustext in the json response returned from the backend (this is already working. If the status is 0 to return to the dashboard and display the user's name (this code is already working) The response to a login request returns a json with the fields below: (if status is 0 the all the fields are set with the user's data, if the status is not 0 all fields are empty except status and statustext. (this code is already working) id firstname surname email status statustext status 0 login and password is correct Where the statustext for each error is shown below::- status 1 user not on file please register status 2 Invalid password status 3 Password required If the user has entered data and the returned status is not 0 then display an alert on the login form The alert shows the statustext returned from the backend. the source code is on github in the login-validation branch [login to view URL]