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746555e | 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 | # AED Rules 4 + 5 — Intention-revealing names; comments say WHY, never WHAT
#
# Context: session establishment after a successful login. The same behavior,
# written twice. Note that the AFTER version has FEWER comments — good names
# removed the need for most of them, and the one comment that remains carries
# information the code cannot: the attack it prevents.
# ── BEFORE ────────────────────────────────────────────────────────────────────
# Cryptic names force a comment per line, and every comment restates the code.
#
# # process the user
# def do_it(u)
# # reset the session
# session.reset
# # set the id
# session[:uid] = u.id
# # set the version
# tmp = u.session_version
# session[:sv] = tmp
# end
# ── AFTER (AED) ───────────────────────────────────────────────────────────────
# The method name states the intent; the locals state what they hold; the one
# surviving comment explains a security decision no name could carry.
def establish_session(user : Users::Regular) : Nil
# Rotate the session id BEFORE writing identity: prevents session fixation
# (an attacker pre-planting a known session id that survives login).
session.reset
session[:user_id] = user.id
session[:session_version] = user.session_version
end
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