Awesome
A Robust URL Parser and Builder for Lua
This small Lua library provides a few functions to parse URL with querystring and build new URL easily.
url = require "net.url"
URL parser
The library converts an URL to a table of the elements as described in RFC : scheme, host, path, etc.
u = url.parse("http://www.example.com/test/?start=10")
print(u.scheme)
-- http
print(u.host)
-- www.example.com
print(u.path)
-- /test/
URL normalization
u = url.parse("http://www.FOO.com:80///foo/../foo/./bar"):normalize()
print(u)
-- http://www.foo.com/foo/bar
URL resolver
URL resolution follows the examples provided in the RFC 2396.
u = url.parse("http://a/b/c/d;p?q"):resolve("../../g")
print(u)
-- http://a/g
Path builder
Path segments can be added using the __div
metatable or u.addSegment()
.
u = url.parse('http://example.com')
u / 'bands' / 'AC/DC'
print(u)
-- http://example.com/bands/AC%2FDC
Module Options
separator
is used to specify which separator is used between query parameters. It is&
by default.cumulative_parameters
is false by default. If true, query parameters with the same name will be stored in a table.legal_in_path
is a table of characters that will not be url encoded in path components.legal_in_query
is a table of characters that will not be url encoded in query values. Query parameters on the other hand only support a small set of legal characters (-_.
).query_plus_is_space
is true by default, so a plus sign in a query value will be converted to %20 (space), not %2B (plus).
If one wants to have the +
sign as is in path segments, one can add it to the list of
legal characters in path. For example:
url = require "net.url"
url.options.legal_in_path["+"] = true;
Querystring parser
The library supports brackets in querystrings, like PHP. It means you can use brackets to build multi-dimensional tables. The parsed querystring has a tostring() helper. As usual with Lua, if no index is specified, it starts from index 1.
query = url.parseQuery("first=abc&a[]=123&a[]=false&b[]=str&c[]=3.5&a[]=last")
print(query)
-- a[1]=123&a[2]=false&a[3]=last&b[1]=str&c[1]=3.5&first=abc
print(query.a[1])
-- 123
Querystring builder
u = url.parse("http://www.example.com")
u.query.foo = "bar"
print(u)
-- http://www.example.com/?foo=bar
u:setQuery{ json = true, skip = 100 }
print(u)
-- http://www.example.com/?json=true&skip=100
Differences with luasocket/url.lua
- Luasocket/url.lua can't parse http://www.example.com?url=net correctly because there are no path.
- Luasocket/url.lua can't clean and normalize url, for example by removing default port, extra zero in port, empty authority, uppercase scheme, domain name.
- Luasocket/url.lua doesn't parse the query string parameters.
- Luasocket/url.lua is less compliant with RFC 2396 and will resolve
http://a/b/c/d;p?q
and :../../../g
tohttp://ag
instead ofhttp://a/g
../../../../g
tohttp://a../g
instead ofhttp://a/g
g;x=1/../y
tohttp://a/b/c/g;x=1/../y
instead ofhttp://a/b/c/y
/./g
tohttp://a/./g
instead ofhttp://a/g
g;x=1/./y
tohttp://a/b/c/g;x=1/./y
instead ofhttp://a/b/c/g;x=1/y