feat: add user's activeness to admin dashboard

[jaeyun0503]

Summary

This pr adds a new feature where the admin can keep track of the active/inactive users on the Admin Dashboard. The feature is added in order to give admin users a better use experience and straightforward overview of users' activeness. A ring is added around the avatars and it will turn green whenever a user is active and gray if a user is inactive.

Closes #3624.

For Developers

Please do the following steps to incorporate with new changes:

• Apply core/scripts/sql/updates/10.sql to your local postgres instance

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Change made to Database

A new table time_log is introduced to the db with primary key being uid that references the uid from user table and last_active as an column to store the last active time of the user. The last_active column can be null and when a user is active, one of the following will happen:

1. If the corresponding uid exists in the time_log table, the last_active will simply be updated.
2. If the corresponding uid does NOT exist in the time_log table, (uid, last_active) will be added to the table.

Context of the Design

The reasons why we chose to create a separate table time_log instead of adding the information to the user table are as follows:

1. Too costly to update user table frequently: When a user becomes "active", last_active will be updated. And how we defined a user to be active is that when a user makes a http request and they hold a valid jwt token that has a lifespan of 15 minutes, the user is active. Whenever the user makes a http request the last_active column will have to be updated. And with a scalable system like Texera, it will become more and more costly to update the information when a large number of users are "active" on the system if the last_active is in the user table.
2. Since there might be more time information that can be added in future regarding user's account creation time, last action time, etc, it is better to bring the time information out and make them as a separate project.

Based on the internal discussions on the design of the tables, we decided to create a time_log table.

Image of Database Diagram

Functionality & Explanation of the Feature

When a user makes a http request, the attribute will be updated in the db. Future changes might be made to this table since we are planning to introduce more attributes like account creation time.

Since every http request triggers the jwtFilter, our design is to upsert the user's last login time record whenever the request triggers the jwtFilter. The upsert function will add a new record if the user never logged in before, and will update the last_login attribute. When the admin visits the admin dashboard, the call to the getUserList will now contain a list of users with a new attribute named lastActive, which is a Unix epoch timestamp in seconds. If a user's lastActive attribute is null or the difference between the current timestamp and its lastActive timestamp is larger than the set threshold (a.k.a active window), the user will be inactive, otherwise active. Here we define the active window as 15 minutes. With this threshold, admin users will be able to know which users were active within the last 15 minutes.

The token's expiration time is set to 15 minutes, and refresh time is set to 16 minutes in order to make sure a user is "logged out" when they don't make anymore http requests. As soon as the system detects that the last active time has a 15 minutes difference with the current time, it will mark the user as inactive.

Screenshot of Feature

[Copilot]

Pull Request Overview

This PR adds a user activity tracking feature to the admin dashboard that allows administrators to visually distinguish between active and inactive users. Active users (those who made HTTP requests within the last 15 minutes) are displayed with a green ring around their avatar, while inactive users have a gray ring.

• Implements user activity tracking by recording last login timestamps in a new time_log database table
• Updates JWT token expiration to 15 minutes with 16-minute refresh interval to align with activity window
• Modifies admin user interface to display visual activity indicators around user avatars

Reviewed Changes

Copilot reviewed 10 out of 18 changed files in this pull request and generated 4 comments.

Show a summary per file

File	Description
core/scripts/sql/updates/10.sql	Creates new time_log table to store user activity timestamps
core/auth/src/main/scala/edu/uci/ics/texera/auth/JwtAuth.scala	Updates JWT token expiration to 15 minutes
core/auth/src/main/scala/edu/uci/ics/texera/auth/JwtAuthFilter.scala	Adds logic to upsert user activity on each authenticated request
core/amber/src/main/scala/edu/uci/ics/texera/web/resource/dashboard/admin/user/AdminUserResource.scala	Implements new endpoint returning users with last activity data
core/gui/src/app/common/type/user.ts	Adds lastActive field to User interface
core/gui/src/app/dashboard/component/admin/user/admin-user.component.*	Implements frontend logic and styling for activity indicators
core/gui/src/app/dashboard/service/admin/user/admin-user.service.ts	Updates service to use new activity-enabled endpoint
core/gui/src/app/common/service/user/auth.service.ts	Adjusts token refresh interval to 16 minutes

[jaeyun0503]

@aicam Please help me assign labels, assignee and reviewers. Thank you so much!

[jaeyun0503]

@aicam @aglinxinyuan Made changes to the code. Re-requesting review.

[aicam]

LGTM

[aglinxinyuan]

LGTM. You don't need to list the files changed.

[jaeyun0503]

@aicam I think an approval is needed from the maintainer's side

[jaeyun0503]

@aicam Final approval needed