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luci-base: switch to lucihttp based POST data processing

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Use the liblucihttp provided multipart and x-www-urlencoded body parsers
and drop the old Lua parsing code.

The C based data parsers are way faster than their old Lua counterparts
while producing less string garbage and more correct results.

While refactoring the luci.http.protocol code, also drop unused functions
and dead code, heavily reducing the module size.

Signed-off-by: Jo-Philipp Wich <jo@mein.io>
This commit is contained in:
Jo-Philipp Wich 2018-04-18 11:36:53 +02:00
parent f52c8d0b7f
commit 59dea0230c
2 changed files with 174 additions and 524 deletions
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599
modules/luci-base/luasrc/http/protocol.lua
View file

@ -1,12 +1,16 @@
-- Copyright 2008 Freifunk Leipzig / Jo-Philipp Wich <jow@openwrt.org> -- Copyright 2008-2018 Jo-Philipp Wich <jo@mein.io>
-- Licensed to the public under the Apache License 2.0. -- Licensed to the public under the Apache License 2.0.
-- This class contains several functions useful for http message- and content -- This class contains several functions useful for http message- and content
-- decoding and to retrive form data from raw http messages. -- decoding and to retrive form data from raw http messages.
module("luci.http.protocol", package.seeall)
local ltn12 = require("luci.ltn12") local require, type, tonumber = require, type, tonumber
local util = require("luci.util") local table, pairs, ipairs, pcall = table, pairs, ipairs, pcall
module "luci.http.protocol"
local ltn12 = require "luci.ltn12"
local lhttp = require "lucihttp"
HTTP_MAX_CONTENT = 1024*8 -- 8 kB maximum content size HTTP_MAX_CONTENT = 1024*8 -- 8 kB maximum content size
@ -14,32 +18,25 @@ HTTP_MAX_CONTENT = 1024*8 -- 8 kB maximum content size
-- Simple parameters are stored as string values associated with the parameter -- Simple parameters are stored as string values associated with the parameter
-- name within the table. Parameters with multiple values are stored as array -- name within the table. Parameters with multiple values are stored as array
-- containing the corresponding values. -- containing the corresponding values.
function urldecode_params( url, tbl ) function urldecode_params(url, tbl)
local parser, name
local params = tbl or { } local params = tbl or { }
if url:find("?") then parser = lhttp.urlencoded_parser(function (what, buffer, length)
url = url:gsub( "^.+%?([^?]+)", "%1" ) if what == parser.TUPLE then
name, value = nil, nil
elseif what == parser.NAME then
name = lhttp.urldecode(buffer)
elseif what == parser.VALUE and name then
params[name] = lhttp.urldecode(buffer) or ""
end end
for pair in url:gmatch( "[^&;]+" ) do return true
end)
-- find key and value if parser then
local key = util.urldecode( pair:match("^([^=]+)") ) parser:parse((url or ""):match("[^?]*$"))
local val = util.urldecode( pair:match("^[^=]+=(.+)$") ) parser:parse(nil)
-- store
if type(key) == "string" and key:len() > 0 then
if type(val) ~= "string" then val = "" end
if not params[key] then
params[key] = val
elseif type(params[key]) ~= "table" then
params[key] = { params[key], val }
else
table.insert( params[key], val )
end
end
end end
return params return params
@ -47,185 +44,37 @@ end
-- separated by "&". Tables are encoded as parameters with multiple values by -- separated by "&". Tables are encoded as parameters with multiple values by
-- repeating the parameter name with each value. -- repeating the parameter name with each value.
function urlencode_params( tbl ) function urlencode_params(tbl)
local enc = "" local k, v
local n, enc = 1, {}
for k, v in pairs(tbl) do for k, v in pairs(tbl) do
if type(v) == "table" then if type(v) == "table" then
local i, v2
for i, v2 in ipairs(v) do for i, v2 in ipairs(v) do
enc = enc .. ( #enc > 0 and "&" or "" ) .. if enc[1] then
util.urlencode(k) .. "=" .. util.urlencode(v2) enc[n] = "&"
n = n + 1
end
enc[n+0] = lhttp.urlencode(k)
enc[n+1] = "="
enc[n+2] = lhttp.urlencode(v2)
n = n + 3
end end
else else
enc = enc .. ( #enc > 0 and "&" or "" ) .. if enc[1] then
util.urlencode(k) .. "=" .. util.urlencode(v) enc[n] = "&"
n = n + 1
end
enc[n+0] = lhttp.urlencode(k)
enc[n+1] = "="
enc[n+2] = lhttp.urlencode(v)
n = n + 3
end end
end end
return enc return table.concat(enc, "")
end
-- (Internal function)
-- Initialize given parameter and coerce string into table when the parameter
-- already exists.
local function __initval( tbl, key )
if tbl[key] == nil then
tbl[key] = ""
elseif type(tbl[key]) == "string" then
tbl[key] = { tbl[key], "" }
else
table.insert( tbl[key], "" )
end
end
-- (Internal function)
-- Initialize given file parameter.
local function __initfileval( tbl, key, filename, fd )
if tbl[key] == nil then
tbl[key] = { file=filename, fd=fd, name=key, "" }
else
table.insert( tbl[key], "" )
end
end
-- (Internal function)
-- Append given data to given parameter, either by extending the string value
-- or by appending it to the last string in the parameter's value table.
local function __appendval( tbl, key, chunk )
if type(tbl[key]) == "table" then
tbl[key][#tbl[key]] = tbl[key][#tbl[key]] .. chunk
else
tbl[key] = tbl[key] .. chunk
end
end
-- (Internal function)
-- Finish the value of given parameter, either by transforming the string value
-- or - in the case of multi value parameters - the last element in the
-- associated values table.
local function __finishval( tbl, key, handler )
if handler then
if type(tbl[key]) == "table" then
tbl[key][#tbl[key]] = handler( tbl[key][#tbl[key]] )
else
tbl[key] = handler( tbl[key] )
end
end
end
-- Table of our process states
local process_states = { }
-- Extract "magic", the first line of a http message.
-- Extracts the message type ("get", "post" or "response"), the requested uri
-- or the status code if the line descripes a http response.
process_states['magic'] = function( msg, chunk, err )
if chunk ~= nil then
-- ignore empty lines before request
if #chunk == 0 then
return true, nil
end
-- Is it a request?
local method, uri, http_ver = chunk:match("^([A-Z]+) ([^ ]+) HTTP/([01]%.[019])$")
-- Yup, it is
if method then
msg.type = "request"
msg.request_method = method:lower()
msg.request_uri = uri
msg.http_version = tonumber( http_ver )
msg.headers = { }
-- We're done, next state is header parsing
return true, function( chunk )
return process_states['headers']( msg, chunk )
end
-- Is it a response?
else
local http_ver, code, message = chunk:match("^HTTP/([01]%.[019]) ([0-9]+) ([^\r\n]+)$")
-- Is a response
if code then
msg.type = "response"
msg.status_code = code
msg.status_message = message
msg.http_version = tonumber( http_ver )
msg.headers = { }
-- We're done, next state is header parsing
return true, function( chunk )
return process_states['headers']( msg, chunk )
end
end
end
end
-- Can't handle it
return nil, "Invalid HTTP message magic"
end
-- Extract headers from given string.
process_states['headers'] = function( msg, chunk )
if chunk ~= nil then
-- Look for a valid header format
local hdr, val = chunk:match( "^([A-Za-z][A-Za-z0-9%-_]+): +(.+)$" )
if type(hdr) == "string" and hdr:len() > 0 and
type(val) == "string" and val:len() > 0
then
msg.headers[hdr] = val
-- Valid header line, proceed
return true, nil
elseif #chunk == 0 then
-- Empty line, we won't accept data anymore
return false, nil
else
-- Junk data
return nil, "Invalid HTTP header received"
end
else
return nil, "Unexpected EOF"
end
end
-- data line by line with the trailing \r\n stripped of.
function header_source( sock )
return ltn12.source.simplify( function()
local chunk, err, part = sock:receive("*l")
-- Line too long
if chunk == nil then
if err ~= "timeout" then
return nil, part
and "Line exceeds maximum allowed length"
or "Unexpected EOF"
else
return nil, err
end
-- Line ok
elseif chunk ~= nil then
-- Strip trailing CR
chunk = chunk:gsub("\r$","")
return chunk, nil
end
end )
end end
-- Content-Type. Stores all extracted data associated with its parameter name -- Content-Type. Stores all extracted data associated with its parameter name
@ -238,286 +87,125 @@ end
-- o Table containing decoded (name, file) and raw (headers) mime header data -- o Table containing decoded (name, file) and raw (headers) mime header data
-- o String value containing a chunk of the file data -- o String value containing a chunk of the file data
-- o Boolean which indicates wheather the current chunk is the last one (eof) -- o Boolean which indicates wheather the current chunk is the last one (eof)
function mimedecode_message_body( src, msg, filecb ) function mimedecode_message_body(src, msg, file_cb)
local parser, header, field
local len, maxlen = 0, tonumber(msg.env.CONTENT_LENGTH or nil)
if msg and msg.env.CONTENT_TYPE then parser, err = lhttp.multipart_parser(msg.env.CONTENT_TYPE, function (what, buffer, length)
msg.mime_boundary = msg.env.CONTENT_TYPE:match("^multipart/form%-data; boundary=(.+)$") if what == parser.PART_INIT then
field = { }
elseif what == parser.HEADER_NAME then
header = buffer:lower()
elseif what == parser.HEADER_VALUE and header then
if header:lower() == "content-disposition" and
lhttp.header_attribute(buffer, nil) == "form-data"
then
field.name = lhttp.header_attribute(buffer, "name")
field.file = lhttp.header_attribute(buffer, "filename")
end end
if not msg.mime_boundary then if field.headers then
return nil, "Invalid Content-Type found" field.headers[header] = buffer
else
field.headers = { [header] = buffer }
end end
elseif what == parser.PART_BEGIN then
return not field.file
local tlen = 0 elseif what == parser.PART_DATA and field.name and length > 0 then
local inhdr = false if field.file then
local field = nil if file_cb then
local store = nil file_cb(field, buffer, false)
local lchunk = nil msg.params[field.name] = msg.params[field.name] or field
else
local function parse_headers( chunk, field ) if not field.fd then
local ok, nx = pcall(require, "nixio")
local stat field.fd = ok and nx.mkstemp(field.name)
repeat
chunk, stat = chunk:gsub(
"^([A-Z][A-Za-z0-9%-_]+): +([^\r\n]+)\r\n",
function(k,v)
field.headers[k] = v
return ""
end
)
until stat == 0
chunk, stat = chunk:gsub("^\r\n","")
-- End of headers
if stat > 0 then
if field.headers["Content-Disposition"] then
if field.headers["Content-Disposition"]:match("^form%-data; ") then
field.name = field.headers["Content-Disposition"]:match('name="(.-)"')
field.file = field.headers["Content-Disposition"]:match('filename="(.+)"$')
end
end end
if not field.headers["Content-Type"] then if field.fd then
field.headers["Content-Type"] = "text/plain" field.fd:write(buffer)
end msg.params[field.name] = msg.params[field.name] or field
if field.name and field.file and filecb then
__initval( msg.params, field.name )
__appendval( msg.params, field.name, field.file )
store = filecb
elseif field.name and field.file then
local nxf = require "nixio"
local fd = nxf.mkstemp(field.name)
__initfileval ( msg.params, field.name, field.file, fd )
if fd then
store = function(hdr, buf, eof)
fd:write(buf)
if (eof) then
fd:seek(0, "set")
end end
end end
else else
store = function( hdr, buf, eof ) field.value = buffer
__appendval( msg.params, field.name, buf )
end end
end
elseif field.name then
__initval( msg.params, field.name )
store = function( hdr, buf, eof ) elseif what == parser.PART_END and field.name then
__appendval( msg.params, field.name, buf ) if field.file and msg.params[field.name] then
if file_cb then
file_cb(field, "", true)
elseif field.fd then
field.fd:seek(0, "set")
end end
else else
store = nil msg.params[field.name] = field.value or ""
end end
return chunk, true field = nil
end
return chunk, false elseif what == parser.ERROR then
end err = buffer
local function snk( chunk )
tlen = tlen + ( chunk and #chunk or 0 )
if msg.env.CONTENT_LENGTH and tlen > tonumber(msg.env.CONTENT_LENGTH) + 2 then
return nil, "Message body size exceeds Content-Length"
end
if chunk and not lchunk then
lchunk = "\r\n" .. chunk
elseif lchunk then
local data = lchunk .. ( chunk or "" )
local spos, epos, found
repeat
spos, epos = data:find( "\r\n--" .. msg.mime_boundary .. "\r\n", 1, true )
if not spos then
spos, epos = data:find( "\r\n--" .. msg.mime_boundary .. "--\r\n", 1, true )
end
if spos then
local predata = data:sub( 1, spos - 1 )
if inhdr then
predata, eof = parse_headers( predata, field )
if not eof then
return nil, "Invalid MIME section header"
elseif not field.name then
return nil, "Invalid Content-Disposition header"
end
end
if store then
store( field, predata, true )
end
field = { headers = { } }
found = found or true
data, eof = parse_headers( data:sub( epos + 1, #data ), field )
inhdr = not eof
end
until not spos
if found then
-- We found at least some boundary. Save
-- the unparsed remaining data for the
-- next chunk.
lchunk, data = data, nil
else
-- There was a complete chunk without a boundary. Parse it as headers or
-- append it as data, depending on our current state.
if inhdr then
lchunk, eof = parse_headers( data, field )
inhdr = not eof
else
-- We're inside data, so append the data. Note that we only append
-- lchunk, not all of data, since there is a chance that chunk
-- contains half a boundary. Assuming that each chunk is at least the
-- boundary in size, this should prevent problems
store( field, lchunk, false )
lchunk, chunk = chunk, nil
end
end
end end
return true return true
end)
return ltn12.pump.all(src, function (chunk)
len = len + (chunk and #chunk or 0)
if maxlen and len > maxlen + 2 then
return nil, "Message body size exceeds Content-Length"
end end
return ltn12.pump.all( src, snk ) if not parser or not parser:parse(chunk) then
return nil, err
end
return true
end)
end end
-- Content-Type. Stores all extracted data associated with its parameter name -- Content-Type. Stores all extracted data associated with its parameter name
-- in the params table within the given message object. Multiple parameter -- in the params table within the given message object. Multiple parameter
-- values are stored as tables, ordinary ones as strings. -- values are stored as tables, ordinary ones as strings.
function urldecode_message_body( src, msg ) function urldecode_message_body(src, msg)
local err, name, value, parser
local len, maxlen = 0, tonumber(msg.env.CONTENT_LENGTH or nil)
local tlen = 0 parser = lhttp.urlencoded_parser(function (what, buffer, length)
local lchunk = nil if what == parser.TUPLE then
name, value = nil, nil
local function snk( chunk ) elseif what == parser.NAME then
name = lhttp.urldecode(buffer)
tlen = tlen + ( chunk and #chunk or 0 ) elseif what == parser.VALUE and name then
msg.params[name] = lhttp.urldecode(buffer) or ""
if msg.env.CONTENT_LENGTH and tlen > tonumber(msg.env.CONTENT_LENGTH) + 2 then elseif what == parser.ERROR then
return nil, "Message body size exceeds Content-Length" err = buffer
elseif tlen > HTTP_MAX_CONTENT then
return nil, "Message body size exceeds maximum allowed length"
end
if not lchunk and chunk then
lchunk = chunk
elseif lchunk then
local data = lchunk .. ( chunk or "&" )
local spos, epos
repeat
spos, epos = data:find("^.-[;&]")
if spos then
local pair = data:sub( spos, epos - 1 )
local key = pair:match("^(.-)=")
local val = pair:match("=([^%s]*)%s*$")
if key and #key > 0 then
__initval( msg.params, key )
__appendval( msg.params, key, val )
__finishval( msg.params, key, urldecode )
end
data = data:sub( epos + 1, #data )
end
until not spos
lchunk = data
end end
return true return true
end)
return ltn12.pump.all(src, function (chunk)
len = len + (chunk and #chunk or 0)
if maxlen and len > maxlen + 2 then
return nil, "Message body size exceeds Content-Length"
elseif len > HTTP_MAX_CONTENT then
return nil, "Message body size exceeds maximum allowed length"
end end
return ltn12.pump.all( src, snk ) if not parser or not parser:parse(chunk) then
end
-- version, message headers and resulting CGI environment variables from the
-- given ltn12 source.
function parse_message_header( src )
local ok = true
local msg = { }
local sink = ltn12.sink.simplify(
function( chunk )
return process_states['magic']( msg, chunk )
end
)
-- Pump input data...
while ok do
-- get data
ok, err = ltn12.pump.step( src, sink )
-- error
if not ok and err then
return nil, err return nil, err
-- eof
elseif not ok then
-- Process get parameters
if ( msg.request_method == "get" or msg.request_method == "post" ) and
msg.request_uri:match("?")
then
msg.params = urldecode_params( msg.request_uri )
else
msg.params = { }
end end
-- Populate common environment variables return true
msg.env = { end)
CONTENT_LENGTH = msg.headers['Content-Length'];
CONTENT_TYPE = msg.headers['Content-Type'] or msg.headers['Content-type'];
REQUEST_METHOD = msg.request_method:upper();
REQUEST_URI = msg.request_uri;
SCRIPT_NAME = msg.request_uri:gsub("?.+$","");
SCRIPT_FILENAME = ""; -- XXX implement me
SERVER_PROTOCOL = "HTTP/" .. string.format("%.1f", msg.http_version);
QUERY_STRING = msg.request_uri:match("?")
and msg.request_uri:gsub("^.+?","") or ""
}
-- Populate HTTP_* environment variables
for i, hdr in ipairs( {
'Accept',
'Accept-Charset',
'Accept-Encoding',
'Accept-Language',
'Connection',
'Cookie',
'Host',
'Referer',
'User-Agent',
} ) do
local var = 'HTTP_' .. hdr:upper():gsub("%-","_")
local val = msg.headers[hdr]
msg.env[var] = val
end
end
end
return msg
end end
-- This function will examine the Content-Type within the given message object -- This function will examine the Content-Type within the given message object
@ -526,17 +214,18 @@ end
-- mime types are supported. If the encountered content encoding can't be -- mime types are supported. If the encountered content encoding can't be
-- handled then the whole message body will be stored unaltered as "content" -- handled then the whole message body will be stored unaltered as "content"
-- property within the given message object. -- property within the given message object.
function parse_message_body( src, msg, filecb ) function parse_message_body(src, msg, filecb)
-- Is it multipart/mime ? local ctype = lhttp.header_attribute(msg.env.CONTENT_TYPE, nil)
if msg.env.REQUEST_METHOD == "POST" and msg.env.CONTENT_TYPE and
msg.env.CONTENT_TYPE:match("^multipart/form%-data")
then
-- Is it multipart/mime ?
if msg.env.REQUEST_METHOD == "POST" and
ctype == "multipart/form-data"
then
return mimedecode_message_body( src, msg, filecb ) return mimedecode_message_body( src, msg, filecb )
-- Is it application/x-www-form-urlencoded ? -- Is it application/x-www-form-urlencoded ?
elseif msg.env.REQUEST_METHOD == "POST" and msg.env.CONTENT_TYPE and elseif msg.env.REQUEST_METHOD == "POST" and
msg.env.CONTENT_TYPE:match("^application/x%-www%-form%-urlencoded") ctype == "application/x-www-form-urlencoded"
then then
return urldecode_message_body( src, msg, filecb ) return urldecode_message_body( src, msg, filecb )
@ -594,21 +283,3 @@ function parse_message_body( src, msg, filecb )
return true return true
end end
end end
statusmsg = {
[200] = "OK",
[206] = "Partial Content",
[301] = "Moved Permanently",
[302] = "Found",
[304] = "Not Modified",
[400] = "Bad Request",
[403] = "Forbidden",
[404] = "Not Found",
[405] = "Method Not Allowed",
[408] = "Request Time-out",
[411] = "Length Required",
[412] = "Precondition Failed",
[416] = "Requested range not satisfiable",
[500] = "Internal Server Error",
[503] = "Server Unavailable",
}

55
modules/luci-base/luasrc/http/protocol.luadoc
View file

@ -8,11 +8,12 @@ module "luci.http.protocol"
---[[ ---[[
Extract and split urlencoded data pairs, separated bei either "&" or ";" Extract and split urlencoded data pairs, separated bei either "&" or ";"
from given url or string. Returns a table with urldecoded values. from given url or string. Returns a table with urldecoded values.
Simple parameters are stored as string values associated with the parameter Simple parameters are stored as string values associated with the parameter
name within the table. Parameters with multiple values are stored as array name within the table. Parameters with multiple values are stored as array
containing the corresponding values. containing the corresponding values.
@class function @class function
@name urldecode_params @name urldecode_params
@param url The url or string which contains x-www-urlencoded form data @param url The url or string which contains x-www-urlencoded form data
@ -23,9 +24,11 @@ containing the corresponding values.
---[[ ---[[
Encode each key-value-pair in given table to x-www-urlencoded format, Encode each key-value-pair in given table to x-www-urlencoded format,
separated by "&".
Tables are encoded as parameters with multiple values by repeating the
parameter name with each value.
separated by "&". Tables are encoded as parameters with multiple values by
repeating the parameter name with each value.
@class function @class function
@name urlencode_params @name urlencode_params
@param tbl Table with the values @param tbl Table with the values
@ -34,21 +37,12 @@ repeating the parameter name with each value.
]] ]]
---[[ ---[[
Creates a ltn12 source from the given socket. The source will return it's Decode a mime encoded http message body with multipart/form-data Content-Type.
data line by line with the trailing \r\n stripped of. Stores all extracted data associated with its parameter name
@class function
@name header_source
@param sock Readable network socket
@return Ltn12 source function
]]
---[[
Decode a mime encoded http message body with multipart/form-data
Content-Type. Stores all extracted data associated with its parameter name
in the params table within the given message object. Multiple parameter in the params table within the given message object. Multiple parameter
values are stored as tables, ordinary ones as strings. values are stored as tables, ordinary ones as strings.
If an optional file callback function is given then it is feeded with the If an optional file callback function is given then it is feeded with the
file contents chunk by chunk and only the extracted file name is stored file contents chunk by chunk and only the extracted file name is stored
within the params table. The callback function will be called subsequently within the params table. The callback function will be called subsequently
@ -56,6 +50,7 @@ with three arguments:
o Table containing decoded (name, file) and raw (headers) mime header data o Table containing decoded (name, file) and raw (headers) mime header data
o String value containing a chunk of the file data o String value containing a chunk of the file data
o Boolean which indicates wheather the current chunk is the last one (eof) o Boolean which indicates wheather the current chunk is the last one (eof)
@class function @class function
@name mimedecode_message_body @name mimedecode_message_body
@param src Ltn12 source function @param src Ltn12 source function
@ -68,10 +63,12 @@ with three arguments:
---[[ ---[[
Decode an urlencoded http message body with application/x-www-urlencoded Decode an urlencoded http message body with application/x-www-urlencoded
Content-Type.
Stores all extracted data associated with its parameter name in the params
table within the given message object. Multiple parameter values are stored
as tables, ordinary ones as strings.
Content-Type. Stores all extracted data associated with its parameter name
in the params table within the given message object. Multiple parameter
values are stored as tables, ordinary ones as strings.
@class function @class function
@name urldecode_message_body @name urldecode_message_body
@param src Ltn12 source function @param src Ltn12 source function
@ -81,27 +78,16 @@ values are stored as tables, ordinary ones as strings.
@see parse_message_header @see parse_message_header
]] ]]
---[[
Try to extract an http message header including information like protocol
version, message headers and resulting CGI environment variables from the
given ltn12 source.
@class function
@name parse_message_header
@param src Ltn12 source function
@return HTTP message object
@see parse_message_body
]]
---[[ ---[[
Try to extract and decode a http message body from the given ltn12 source. Try to extract and decode a http message body from the given ltn12 source.
This function will examine the Content-Type within the given message object This function will examine the Content-Type within the given message object
to select the appropriate content decoder. to select the appropriate content decoder.
Currently the application/x-www-urlencoded and application/form-data Currently the application/x-www-urlencoded and application/form-data
mime types are supported. If the encountered content encoding can't be mime types are supported. If the encountered content encoding can't be
handled then the whole message body will be stored unaltered as "content" handled then the whole message body will be stored unaltered as "content"
property within the given message object. property within the given message object.
@class function @class function
@name parse_message_body @name parse_message_body
@param src Ltn12 source function @param src Ltn12 source function
@ -111,10 +97,3 @@ property within the given message object.
@return String containing the error if unsuccessful @return String containing the error if unsuccessful
@see parse_message_header @see parse_message_header
]] ]]
---[[
Table containing human readable messages for several http status codes.
@class table
]]