Activity Diagram Example for User Registration and Email Verification

Process Overview

The process describes how a new user registers for an account and verifies their email address to activate the account. The flow includes user input, system validation, email notification, and account activation.

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Activities and Flow

1. Start
   • The process begins when a new user navigates to the “Register” page.
2. Fill Registration Form
   • Input: User enters first name, last name, email, and password.
   • Decision Point: Check if all required fields are filled and the data format is valid.
     • Yes: Proceed to “Submit Registration Form.”
     • No: Display error messages and return to “Fill Registration Form.”
3. Submit Registration Form
   • Action: User clicks the “Register” button.
   • System Process: Validate the input data against security and format rules (e.g., email format, password strength).
4. Decision Point: Data Validation
   • Condition: Is the input data valid?
     • Yes: Proceed to “Create User Account.”
     • No: Display error messages and return to “Fill Registration Form.”
5. Create User Account
   • Action: System creates a user account in the database.
   • System Process: Store user data securely, hash and salt the password, and set the account status to “Pending Verification.”
6. Send Verification Email
   • Action: System generates a verification email with a unique activation link and sends it to the user’s email address.
   • System Process: Wait for the user to click the activation link.
7. Decision Point: User Clicks Verification Link
   • Condition: Has the user clicked the email verification link?
     • Yes: Proceed to “Activate Account.”
     • No: System sends a reminder email if the user has not verified within 24 hours.
8. Activate Account
   • Action: System verifies the activation link and sets the account status to “Active.”
   • Output: Display a success message, “Your account has been successfully activated!”
9. End
   • The process ends with the user being able to log in to their activated account.

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Diagram Layout Description

1. Start Node: Represented by a solid circle at the top of the diagram.
2. Activity Nodes: Represented by rounded rectangles for each activity (e.g., “Fill Registration Form,” “Submit Registration Form”).
3. Decision Nodes: Represented by diamonds for conditional logic (e.g., “Is the data valid?”).
4. Arrows: Indicate the flow of the process, connecting activities and decision points.
5. End Node: Represented by a solid circle with a border at the bottom of the diagram, indicating the end of the process.

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Example Flow

1. User Action: The user fills in their details and submits the form.
2. System Validation: The system checks the details and either creates the account or returns an error.
3. Email Verification: The user receives and clicks the verification link, activating their account.
4. Account Activation: The account is activated, and the user is ready to log in.