Use Case Diagram

Use Cases

###Use Case 1 ### Name: Sign up

Actor: Guest

Goal : Signing up to the system

Preconditions:

• Guest must have an email address.
• Guest must choose a unique username.
• Guest must write their real name.
• Guest must set a password.
• Password must consists of at least 9 characters.
• Password must be consist at least one number, one upper case letter.
• Password must be verified by typing it again.
• Guest must choose a country and a city.
• Guest must choose an age.
• Guest must enter a valid phone number.

Steps:

• Guest enters a username, password, email, country, city, phone number, age.
• Guest verifies the verification message on their phone or mailbox.

Post Conditions:

• Guest becomes a user.
• User can log in by email and password.
• User can log in by phone number and password.

###Use Case 2### Name: Log in

Actor: User

Goal: Logging into the system

Preconditions :

• User must enter a valid phone number or email.
• User must enter the matching password of the email or the phone number.

Steps

• User enters their phone number or email or username with the matching password.
• System checks whether the given information exists in the system.

Post Conditions :

• If the given information does not exist in the system, the system asks to log in again.

Use Case 3

Name: Search

Actor: User

Goal: Search topics by the given keyword

Preconditions:

• User must enter at least 3 characters.
• The given keyword must have at least 2 subsequent characters that are not white space.

Steps:

• System must search the topics by an algorithm which brings the recommended and related topics to the top.

Post Condition :

• System must show a message about the details of search.
• System must ask for a proper keyword when the given keyword is not a valid one.

Use Case 4

Name: Deactivating a Profile

Actor: User

Goal: Deactivating a profile

Preconditions

• User must enter the password.
• User must enter the same password again.
• User must enter the code that is sent by the system through phone or email.

Steps :

• The system will send a verification message through phone and email.
• The user's profile will be deactivated.

Post Condition :

• The profile gets deactivated.
• The profile will not be deactivated if the verification code is not entered, or if the passwords are not matching, or if the password is wrong.

Use Case 5

Name: Rate

Actor: Registered User(Student or Teacher)

Goal: Rating a topic teacher or a question.

Preconditions:

• User must be logged in.
• User must be browsing the page on which question/topic is posted.

Steps:

• User assigns an integer between 1 and 5(both inclusive) as a feedback for the contribution that the object of rating makes to the community.

Post Conditions:

• System will display the updated average rating of the object(topic, question or teacher).
• User will be forbidden to rate the same object once again unless he/she cancels his/her previous rating.

Use Case 6

Name: Create Topic

Actor: Teacher

Goal: Creating a topic

Preconditions:

• Teacher must be logged in.

Steps:

• Teacher types the topic name(a.k.a topic's title).
• Teacher writes an introduction for the topic.
• Teacher uploads the content of his/her choice(Choices are images, text or video).
• Teacher puts on some tags that he/she thinks are suitable for the topic he/she intends to create.
• Teacher may make a quiz about the topic.

Post Conditions:

• Registered users can display the topic.
• Registered users can comment on the topic.
• Registered users can report the topic.
• Registered users can search the story with topics title and the tags.
• The teacher who created the topic may add or erase content from the topic.
• Registered users can ask questions and post messages on the discussion page of the topic.
• Registered users may take on quizzes(if there are any) and see how well they scored.