Simple generate_token service, independent of the rest of the nitcorn framework

Redefined classes

redef class Sys

nitcorn :: token $ Sys

The main class of the program.

All class definitions

redef class Sys

nitcorn :: token $ Sys

The main class of the program.
package_diagram nitcorn::token token base64 base64 nitcorn::token->base64 core core base64->core ...core ... ...core->core nitcorn::sessions sessions nitcorn::sessions->nitcorn::token nitcorn::file_server file_server nitcorn::file_server->nitcorn::sessions nitcorn::file_server... ... nitcorn::file_server...->nitcorn::file_server

Ancestors

module abstract_collection

core :: abstract_collection

Abstract collection classes and services.
module abstract_text

core :: abstract_text

Abstract class for manipulation of sequences of characters
module array

core :: array

This module introduces the standard array structure.
module bitset

core :: bitset

Services to handle BitSet
module bytes

core :: bytes

Services for byte streams and arrays
module circular_array

core :: circular_array

Efficient data structure to access both end of the sequence.
module codec_base

core :: codec_base

Base for codecs to use with streams
module codecs

core :: codecs

Group module for all codec-related manipulations
module collection

core :: collection

This module define several collection classes.
module core

core :: core

Standard classes and methods used by default by Nit programs and libraries.
module environ

core :: environ

Access to the environment variables of the process
module error

core :: error

Standard error-management infrastructure.
module exec

core :: exec

Invocation and management of operating system sub-processes.
module file

core :: file

File manipulations (create, read, write, etc.)
module fixed_ints

core :: fixed_ints

Basic integers of fixed-precision
module fixed_ints_text

core :: fixed_ints_text

Text services to complement fixed_ints
module flat

core :: flat

All the array-based text representations
module gc

core :: gc

Access to the Nit internal garbage collection mechanism
module hash_collection

core :: hash_collection

Introduce HashMap and HashSet.
module iso8859_1

core :: iso8859_1

Codec for ISO8859-1 I/O
module kernel

core :: kernel

Most basic classes and methods.
module list

core :: list

This module handle double linked lists
module math

core :: math

Mathematical operations
module native

core :: native

Native structures for text and bytes
module numeric

core :: numeric

Advanced services for Numeric types
module protocol

core :: protocol

module queue

core :: queue

Queuing data structures and wrappers
module range

core :: range

Module for range of discrete objects.
module re

core :: re

Regular expression support for all services based on Pattern
module ropes

core :: ropes

Tree-based representation of a String.
module sorter

core :: sorter

This module contains classes used to compare things and sorts arrays.
module stream

core :: stream

Input and output streams of characters
module text

core :: text

All the classes and methods related to the manipulation of text entities
module time

core :: time

Management of time and dates
module union_find

core :: union_find

union–find algorithm using an efficient disjoint-set data structure
module utf8

core :: utf8

Codec for UTF-8 I/O

Parents

module base64

base64 :: base64

Offers the base 64 encoding and decoding algorithms

Children

module sessions

nitcorn :: sessions

Automated session management

Descendants

module a_star-m

a_star-m

module example_angular

popcorn :: example_angular

This is an example of how to use angular.js with popcorn
module file_server

nitcorn :: file_server

Provides the FileServer action, which is a standard and minimal file server
module hooks

github :: hooks

Github hook event listening with nitcorn.
module htcpcp_server

nitcorn :: htcpcp_server

A server that implements HTCPCP. At the moment there are no additions.
module loader

github :: loader

module nitcorn

nitcorn :: nitcorn

The nitcorn Web server framework creates server-side Web apps in Nit
module nitcorn_hello_world

nitcorn :: nitcorn_hello_world

Hello World Web server example
module pop_auth

popcorn :: pop_auth

Authentification handlers.
module pop_handlers

popcorn :: pop_handlers

Route handlers.
module pop_json

popcorn :: pop_json

Introduce useful services for JSON REST API handlers.
module pop_routes

popcorn :: pop_routes

Internal routes representation.
module pop_sessions

popcorn :: pop_sessions

Session handlers
module pop_tasks

popcorn :: pop_tasks

Popcorn threaded tasks
module pop_templates

popcorn :: pop_templates

Template rendering for popcorn
module pop_tests

popcorn :: pop_tests

Popcorn testing services
module popcorn

popcorn :: popcorn

Application server abstraction on top of nitcorn.
module pthreads

nitcorn :: pthreads

Activate the use of pthreads with nitcorn
module restful

nitcorn :: restful

Support module for the nitrestful tool and the restful annotation
module restful_annot

nitcorn :: restful_annot

Example for the restful annotation documented at lib/nitcorn/restful.nit
module simple_file_server

nitcorn :: simple_file_server

Basic file server on port 80 by default, may require root to execute
# Simple `generate_token` service, independent of the rest of the nitcorn framework
module token

import base64

# Generate a random token of `length` chars long
#
# The default value of `length` is 64, but it may change in the future.
#
# On Linux, `/dev/urandom` is used as source of random data.
# On other platforms, `rand` is used to generate pseudo-random data.
# using `rand` can be forced with `force_rand`.
#
# Uses `base64` to represent random bytes in the readable ASCII range.
#
# ~~~
# srand_from 0
# assert generate_token(4,  force_rand=true) == "AMzV"
# assert generate_token(8,  force_rand=true) == "G8Oibf+s"
# assert generate_token(16, force_rand=true) == "VUCPPlWLR8lZQvbb"
# assert generate_token(32, force_rand=true) == "JtJB9vJd+u3c6dyL+Q8U5IKZIueRoZ6h"
# assert generate_token(    force_rand=true) == "+59Ev7/35sOPeq1y8mI5+npAE1SYbfhVgGeDAq2vo5N3mnWxSJvucd6H3HwxT8v8"
# ~~~
fun generate_token(length: nullable Int, force_rand: nullable Bool): String
do
	length = length or else 64

	# TODO generate more entropy

	# Generate random bytes
	var bin_length = ((length.to_f/4.0).ceil * 3.0).to_i
	var bytes = null

	var linux_random = "/dev/urandom"
	if linux_random.file_exists then
		# Use Linux's random number generator
		var reader = new FileReader.open(linux_random)
		bytes = reader.read_bytes(bin_length)
		reader.close
	end

	# TODO other operating systems random number generators

	# Fallback
	if bytes == null or bytes.length != bin_length or force_rand == true then
		bytes = new Bytes.with_capacity(bin_length)
		for i in bin_length.times do bytes.add 256.rand
	end

	# Encode in base64 so it is readable
	var str = bytes.encode_base64.to_s
	if str.length > length then
		# This happens if `length % 4 != 0`
		str = str.substring(0, length)
	end
	return str
end
lib/nitcorn/token.nit:15,1--71,3