how to design a project based system to make so many resource under project?

i want to design a system it is project based system, many resource is organized in project, and the url pattern will like this

• /projects/{project_a}/dashboard
• /projects/{project_a}/issues
• /projects/{project_a}/issues/{issues_id}
• /projects/{project_a}/users
• /projects/{project_a}/tasks
• /projects/{project_a}/tasks/{task_id}/attachments and i do not want to let every controller like ProjectXXXController, and make every jpa query with a where project_id equals xxx clause, how to smart design it? and is multi-tenant pattern a good choose?

a solution for project based system design