nl_tokens: 封装中间件
pl_tokens: function wrapMiddleware ( fn ) { assert ( typeof fn === 'function' , ` assert ( fn . length >= 2 , ` if ( fn . length === 2 ) { return function ( req , res , next ) { let p = null ; try { p = fn ( req , <mask> ) ; } catch ( err ) { return next ( err ) ; } p . then ( _ => next ( ) ) . catch ( err => next ( err ) ) ; } ; } return fn ; }