feat: regex pattern in variables

[vm-001]

Summary

Allows regular expression to be defined in variables. The limitation of the current implementation is that it does not allow defining a regex pattern crossing multiple URL segments, for example, {var:[/0-9a-z]+}.

Usage:

local Router = require "radix-router"
local router = Router.new({
  {
    paths = { "/users/{id:\\d+}/profile-{year:\\d{4}}.{format:(html|pdf)}" },
    handler = "1"
  },
  {
    paths = { "/users/{uuid:[0-9a-f]{8}-[0-9a-f]{4}-[0-9a-f]{4}-[0-9a-f]{4}-[0-9a-f]{12}}" },
    handler = "2"
  },
})
assert("1" == router:match("/users/100/profile-2024.pdf"))
assert("2" == router:match("/users/00000000-0000-0000-0000-000000000000"))

Benchmark

From the benchmark result, the simple regex is only ~1x slower than the simple variable.

test case	route number	ns/op	OPS	RSS
static path	100000	0.0171333	58,365,872	48.69 MB
simple variable	100000	0.0844033	11,847,877	99.97 MB
simple variable	1000000	0.087095	11,481,675	1000.41 MB
simple prefix	100000	0.0730344	13,692,177	99.92 MB
simple regex	100000	0.14444	6,923,289	126.64 MB
complex variable	100000	0.858975	1,164,178	140.08 MB
simple variable binding	100000	0.1843245	5,425,214	99.94 MB
github	609	0.38436	2,601,727	2.69 MB

Expand output

RADIX_ROUTER_ROUTES=100000 RADIX_ROUTER_TIMES=10000000 luajit benchmark/static-paths.lua
========== static path ==========
routes  :	100000
times   :	10000000
elapsed :	0.171333 s
QPS     :	58365872
ns/op   :	0.0171333 ns
path    :	/50000
handler :	50000
Memory  :	48.69 MB

RADIX_ROUTER_ROUTES=100000 RADIX_ROUTER_TIMES=10000000 luajit benchmark/simple-variable.lua
========== variable ==========
routes  :	100000
times   :	10000000
elapsed :	0.844033 s
QPS     :	11847877
ns/op   :	0.0844033 ns
path    :	/1/foo
handler :	1
Memory  :	99.97 MB

RADIX_ROUTER_ROUTES=1000000 RADIX_ROUTER_TIMES=10000000 luajit benchmark/simple-variable.lua
========== variable ==========
routes  :	1000000
times   :	10000000
elapsed :	0.870953 s
QPS     :	11481675
ns/op   :	0.0870953 ns
path    :	/1/foo
handler :	1
Memory  :	1000.41 MB

RADIX_ROUTER_ROUTES=100000 RADIX_ROUTER_TIMES=10000000 luajit benchmark/simple-prefix.lua
========== prefix ==========
routes  :	100000
times   :	10000000
elapsed :	0.730344 s
QPS     :	13692177
ns/op   :	0.0730344 ns
path    :	/1/a
handler :	1
Memory  :	99.92 MB

RADIX_ROUTER_ROUTES=100000 RADIX_ROUTER_TIMES=1000000 luajit benchmark/simple-regex.lua
========== regex ==========
routes  :	100000
times   :	1000000
elapsed :	0.14444 s
QPS     :	6923289
ns/op   :	0.14444 ns
path    :	/1/a
handler :	1
Memory  :	126.64 MB

RADIX_ROUTER_ROUTES=100000 RADIX_ROUTER_TIMES=1000000 luajit benchmark/complex-variable.lua
========== variable ==========
routes  :	100000
times   :	1000000
elapsed :	0.858975 s
QPS     :	1164178
ns/op   :	0.858975 ns
path    :	/aa/bb/cc/dd/ee/ff/gg/hh/ii/jj/kk/ll/mm/nn/oo/pp/qq/rr/ss/tt/uu/vv/ww/xx/yy/zz50000
handler :	50000
Memory  :	140.08 MB

RADIX_ROUTER_ROUTES=100000 RADIX_ROUTER_TIMES=10000000 luajit benchmark/simple-variable-binding.lua
========== variable ==========
routes  :	100000
times   :	10000000
elapsed :	1.843245 s
QPS     :	5425214
ns/op   :	0.1843245 ns
path    :	/1/foo
handler :	1
params : name = foo
Memory  :	99.94 MB

RADIX_ROUTER_TIMES=1000000 luajit benchmark/github-routes.lua
========== github apis ==========
routes  :	609
times   :	1000000
elapsed :	0.38436 s
QPS     :	2601727
ns/op   :	0.38436 ns
path    :	/repos/vm-001/lua-radix-router/import
handler :	/repos/{owner}/{repo}/import
Memory  :	2.69 MB