deno run app.ts
or by setting flags
deno run --allow-env --allow-net app.ts
GET /students : List All the students
GET /students/{roll_no} : List requested student details, returns error if not found.
POST /students : Adds a new student
PUT /students/{roll_no} : Updates requested students details, returns error if not found.
DELETE /students/{roll_no} : Deletes requested students detail, returns error if not found.
Line by Line Guide here.