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- -- -----------------------------------------------------------------------------
- -- -- URI parsing, composition and relative URL resolution
- -- -- LuaSocket toolkit.
- -- -- Author: Diego Nehab
- -- -----------------------------------------------------------------------------
-
- -- -----------------------------------------------------------------------------
- -- -- Declare module
- -- -----------------------------------------------------------------------------
- -- local string = require("string")
- -- local base = _G
- -- local table = require("table")
- -- local socket = require("socket")
-
- -- socket.url = {}
- -- local _M = socket.url
-
- -- -----------------------------------------------------------------------------
- -- -- Module version
- -- -----------------------------------------------------------------------------
- -- _M._VERSION = "URL 1.0.3"
-
- -- -----------------------------------------------------------------------------
- -- -- Encodes a string into its escaped hexadecimal representation
- -- -- Input
- -- -- s: binary string to be encoded
- -- -- Returns
- -- -- escaped representation of string binary
- -- -----------------------------------------------------------------------------
- -- function _M.escape(s)
- -- return (string.gsub(s, "([^A-Za-z0-9_])", function(c)
- -- return string.format("%%%02x", string.byte(c))
- -- end))
- -- end
-
- -- -----------------------------------------------------------------------------
- -- -- Protects a path segment, to prevent it from interfering with the
- -- -- url parsing.
- -- -- Input
- -- -- s: binary string to be encoded
- -- -- Returns
- -- -- escaped representation of string binary
- -- -----------------------------------------------------------------------------
- -- local function make_set(t)
- -- local s = {}
- -- for i,v in base.ipairs(t) do
- -- s[t[i]] = 1
- -- end
- -- return s
- -- end
-
- -- -- these are allowed withing a path segment, along with alphanum
- -- -- other characters must be escaped
- -- local segment_set = make_set {
- -- "-", "_", ".", "!", "~", "*", "'", "(",
- -- ")", ":", "@", "&", "=", "+", "$", ",",
- -- }
-
- -- local function protect_segment(s)
- -- return string.gsub(s, "([^A-Za-z0-9_])", function (c)
- -- if segment_set[c] then return c
- -- else return string.format("%%%02x", string.byte(c)) end
- -- end)
- -- end
-
- -- -----------------------------------------------------------------------------
- -- -- Encodes a string into its escaped hexadecimal representation
- -- -- Input
- -- -- s: binary string to be encoded
- -- -- Returns
- -- -- escaped representation of string binary
- -- -----------------------------------------------------------------------------
- -- function _M.unescape(s)
- -- return (string.gsub(s, "%%(%x%x)", function(hex)
- -- return string.char(base.tonumber(hex, 16))
- -- end))
- -- end
-
- -- -----------------------------------------------------------------------------
- -- -- Builds a path from a base path and a relative path
- -- -- Input
- -- -- base_path
- -- -- relative_path
- -- -- Returns
- -- -- corresponding absolute path
- -- -----------------------------------------------------------------------------
- -- local function absolute_path(base_path, relative_path)
- -- if string.sub(relative_path, 1, 1) == "/" then return relative_path end
- -- local path = string.gsub(base_path, "[^/]*$", "")
- -- path = path .. relative_path
- -- path = string.gsub(path, "([^/]*%./)", function (s)
- -- if s ~= "./" then return s else return "" end
- -- end)
- -- path = string.gsub(path, "/%.$", "/")
- -- local reduced
- -- while reduced ~= path do
- -- reduced = path
- -- path = string.gsub(reduced, "([^/]*/%.%./)", function (s)
- -- if s ~= "../../" then return "" else return s end
- -- end)
- -- end
- -- path = string.gsub(reduced, "([^/]*/%.%.)$", function (s)
- -- if s ~= "../.." then return "" else return s end
- -- end)
- -- return path
- -- end
-
- -- -----------------------------------------------------------------------------
- -- -- Parses a url and returns a table with all its parts according to RFC 2396
- -- -- The following grammar describes the names given to the URL parts
- -- -- <url> ::= <scheme>://<authority>/<path>;<params>?<query>#<fragment>
- -- -- <authority> ::= <userinfo>@<host>:<port>
- -- -- <userinfo> ::= <user>[:<password>]
- -- -- <path> :: = {<segment>/}<segment>
- -- -- Input
- -- -- url: uniform resource locator of request
- -- -- default: table with default values for each field
- -- -- Returns
- -- -- table with the following fields, where RFC naming conventions have
- -- -- been preserved:
- -- -- scheme, authority, userinfo, user, password, host, port,
- -- -- path, params, query, fragment
- -- -- Obs:
- -- -- the leading '/' in {/<path>} is considered part of <path>
- -- -----------------------------------------------------------------------------
- -- function _M.parse(url, default)
- -- -- initialize default parameters
- -- local parsed = {}
- -- for i,v in base.pairs(default or parsed) do parsed[i] = v end
- -- -- empty url is parsed to nil
- -- if not url or url == "" then return nil, "invalid url" end
- -- -- remove whitespace
- -- -- url = string.gsub(url, "%s", "")
- -- -- get fragment
- -- url = string.gsub(url, "#(.*)$", function(f)
- -- parsed.fragment = f
- -- return ""
- -- end)
- -- -- get scheme
- -- url = string.gsub(url, "^([%w][%w%+%-%.]*)%:",
- -- function(s) parsed.scheme = s; return "" end)
- -- -- get authority
- -- url = string.gsub(url, "^//([^/]*)", function(n)
- -- parsed.authority = n
- -- return ""
- -- end)
- -- -- get query string
- -- url = string.gsub(url, "%?(.*)", function(q)
- -- parsed.query = q
- -- return ""
- -- end)
- -- -- get params
- -- url = string.gsub(url, "%;(.*)", function(p)
- -- parsed.params = p
- -- return ""
- -- end)
- -- -- path is whatever was left
- -- if url ~= "" then parsed.path = url end
- -- local authority = parsed.authority
- -- if not authority then return parsed end
- -- authority = string.gsub(authority,"^([^@]*)@",
- -- function(u) parsed.userinfo = u; return "" end)
- -- authority = string.gsub(authority, ":([^:%]]*)$",
- -- function(p) parsed.port = p; return "" end)
- -- if authority ~= "" then
- -- -- IPv6?
- -- parsed.host = string.match(authority, "^%[(.+)%]$") or authority
- -- end
- -- local userinfo = parsed.userinfo
- -- if not userinfo then return parsed end
- -- userinfo = string.gsub(userinfo, ":([^:]*)$",
- -- function(p) parsed.password = p; return "" end)
- -- parsed.user = userinfo
- -- return parsed
- -- end
-
- -- -----------------------------------------------------------------------------
- -- -- Rebuilds a parsed URL from its components.
- -- -- Components are protected if any reserved or unallowed characters are found
- -- -- Input
- -- -- parsed: parsed URL, as returned by parse
- -- -- Returns
- -- -- a stringing with the corresponding URL
- -- -----------------------------------------------------------------------------
- -- function _M.build(parsed)
- -- local ppath = _M.parse_path(parsed.path or "")
- -- local url = _M.build_path(ppath)
- -- if parsed.params then url = url .. ";" .. parsed.params end
- -- if parsed.query then url = url .. "?" .. parsed.query end
- -- local authority = parsed.authority
- -- if parsed.host then
- -- authority = parsed.host
- -- if string.find(authority, ":") then -- IPv6?
- -- authority = "[" .. authority .. "]"
- -- end
- -- if parsed.port then authority = authority .. ":" .. parsed.port end
- -- local userinfo = parsed.userinfo
- -- if parsed.user then
- -- userinfo = parsed.user
- -- if parsed.password then
- -- userinfo = userinfo .. ":" .. parsed.password
- -- end
- -- end
- -- if userinfo then authority = userinfo .. "@" .. authority end
- -- end
- -- if authority then url = "//" .. authority .. url end
- -- if parsed.scheme then url = parsed.scheme .. ":" .. url end
- -- if parsed.fragment then url = url .. "#" .. parsed.fragment end
- -- -- url = string.gsub(url, "%s", "")
- -- return url
- -- end
-
- -- -----------------------------------------------------------------------------
- -- -- Builds a absolute URL from a base and a relative URL according to RFC 2396
- -- -- Input
- -- -- base_url
- -- -- relative_url
- -- -- Returns
- -- -- corresponding absolute url
- -- -----------------------------------------------------------------------------
- -- function _M.absolute(base_url, relative_url)
- -- local base_parsed
- -- if base.type(base_url) == "table" then
- -- base_parsed = base_url
- -- base_url = _M.build(base_parsed)
- -- else
- -- base_parsed = _M.parse(base_url)
- -- end
- -- local relative_parsed = _M.parse(relative_url)
- -- if not base_parsed then return relative_url
- -- elseif not relative_parsed then return base_url
- -- elseif relative_parsed.scheme then return relative_url
- -- else
- -- relative_parsed.scheme = base_parsed.scheme
- -- if not relative_parsed.authority then
- -- relative_parsed.authority = base_parsed.authority
- -- if not relative_parsed.path then
- -- relative_parsed.path = base_parsed.path
- -- if not relative_parsed.params then
- -- relative_parsed.params = base_parsed.params
- -- if not relative_parsed.query then
- -- relative_parsed.query = base_parsed.query
- -- end
- -- end
- -- else
- -- relative_parsed.path = absolute_path(base_parsed.path or "",
- -- relative_parsed.path)
- -- end
- -- end
- -- return _M.build(relative_parsed)
- -- end
- -- end
-
- -- -----------------------------------------------------------------------------
- -- -- Breaks a path into its segments, unescaping the segments
- -- -- Input
- -- -- path
- -- -- Returns
- -- -- segment: a table with one entry per segment
- -- -----------------------------------------------------------------------------
- -- function _M.parse_path(path)
- -- local parsed = {}
- -- path = path or ""
- -- --path = string.gsub(path, "%s", "")
- -- string.gsub(path, "([^/]+)", function (s) table.insert(parsed, s) end)
- -- for i = 1, #parsed do
- -- parsed[i] = _M.unescape(parsed[i])
- -- end
- -- if string.sub(path, 1, 1) == "/" then parsed.is_absolute = 1 end
- -- if string.sub(path, -1, -1) == "/" then parsed.is_directory = 1 end
- -- return parsed
- -- end
-
- -- -----------------------------------------------------------------------------
- -- -- Builds a path component from its segments, escaping protected characters.
- -- -- Input
- -- -- parsed: path segments
- -- -- unsafe: if true, segments are not protected before path is built
- -- -- Returns
- -- -- path: corresponding path stringing
- -- -----------------------------------------------------------------------------
- -- function _M.build_path(parsed, unsafe)
- -- local path = ""
- -- local n = #parsed
- -- if unsafe then
- -- for i = 1, n-1 do
- -- path = path .. parsed[i]
- -- path = path .. "/"
- -- end
- -- if n > 0 then
- -- path = path .. parsed[n]
- -- if parsed.is_directory then path = path .. "/" end
- -- end
- -- else
- -- for i = 1, n-1 do
- -- path = path .. protect_segment(parsed[i])
- -- path = path .. "/"
- -- end
- -- if n > 0 then
- -- path = path .. protect_segment(parsed[n])
- -- if parsed.is_directory then path = path .. "/" end
- -- end
- -- end
- -- if parsed.is_absolute then path = "/" .. path end
- -- return path
- -- end
-
- -- return _M
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