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Task/SQL-based-authentication/Sidef/sql-based-authentication.sidef

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+require('DBI')
+
+ # returns a database handle configured to throw an exception on query errors
+func connect_db(dbname, host, user, pass) {
+    var db = %s<DBI>.connect("dbi:mysql:#{dbname}:#{host}", user, pass)
+    db || die (global DBI::errstr)
+    db{:RaiseError} = 1
+    db
+}
+
+ # if the user was successfully created, returns its user id.
+ # if the name was already in use, returns nil.
+func create_user(db, user, pass) {
+    var salt = "C*".pack(16.of { 256.irand }...)
+    db.do(
+        "INSERT IGNORE INTO users (username, pass_salt, pass_md5)
+         VALUES (?, ?, unhex(md5(concat(pass_salt, ?))))", nil, user, salt, pass
+    ) ? db{:mysql_insertid} : nil
+}
+
+ # if the user is authentic, returns its user id.  otherwise returns nil.
+func authenticate_user(db, user, pass) {
+    db.selectrow_array("SELECT userid FROM users WHERE
+        username=? AND pass_md5=unhex(md5(concat(pass_salt, ?)))",
+        nil, user, pass
+    )
+}