typeset google spreadsheets directly in Luatex

ltx-gdocs-spreadsheet.tex

%% http://tex.stackexchange.com/q/131500

\documentclass {scrartcl}

\usepackage         {luatexbase}
\RequireLuaModule   {lualibs}
\usepackage         {luaotfload} %% recommended, in that order!
\RequireLuaModule   {spreadsheet}

\makeatletter

\protected \def \googlespreadsheet {%
  \@ifnextchar[\googlespreadsheetopt
               {\googlespreadsheetopt[]}%
}

\def \googlespreadsheetopt [#1]#2{%
  \edef \currentspreadsheetoptions {#1}%
  \directlua {
    packagedata.spreadsheet.urihandler ([[\currentspreadsheetoptions]],
                                        [[\detokenize {#2}]])
  }%
}

\makeatother

\begin {document}

  \input knuth

  \begin {table}
    \googlespreadsheet [center,dump]
      {https://docs.google.com/spreadsheet/ccc?key=0Amykmqr4Of-MdEVIUUcyYld3WTJhZnJHRkgwSF9CaUE&usp=sharing}
  \end {table}

  \input knuth

\end {document}

spreadsheet.lua

#!/usr/bin/env texlua
-----------------------------------------------------------------------
--         FILE:  spreadsheet.lua
--  DESCRIPTION:  retrieve and typeset spreadsheets from google docs
-- REQUIREMENTS:  Luatex, Luasec
--       AUTHOR:  Philipp Gesang (Phg), <phg42.2a@gmail.com>
--      VERSION:  1.0
--      CREATED:  2013-09-06 17:26:50+0200
-----------------------------------------------------------------------
--

packagedata                   = packagedata or { }
packagedata.spreadsheet       = packagedata.spreadsheet or { }
local spreadsheet             = packagedata.spreadsheet

spreadsheet.module_info = {
  name          = "spreadsheet",
  version       = 0.0,
  date          = "2013/09/06",
  description   = "Typeset spreadsheets from Google Docs",
  author        = "Philipp Gesang",
  copyright     = "Philipp Gesang",
  license       = "BSD 2 clause",
}

if not config.lualibs then
  config                        = config or { }
  config.lualibs                = config.lualibs or { }
  config.lualibs.load_extended  = true

  require "lualibs"
end

if not caches then
  local u = utilities
  require "luaotfload-basics-gen"
  u.storage = utilities.storage
  utilities = u
end

local lpeg                    = require "lpeg"
local md5                     = require "md5"
local socket                  = require "socket"
local ssl                     = require "ssl"
local http                    = require "socket.http"
local https                   = require "ssl.https"

local stringformat            = string.format
local stringrep               = string.rep
local tableconcat             = table.concat
local tabletohash             = table.tohash
local texiowrite_nl           = texio.write_nl
local getwritablepath         = caches.getwritablepath
local md5sumhexa              = md5.sumhexa
local lfsisfile               = lfs.isfile
local ioloaddata              = io.loaddata
local iosavedata              = io.savedata
local texsprint               = tex.sprint

local unpack                  = unpack or table.unpack
local tonumber                = tonumber

local sockettcp               = socket.tcp
local sslwrap                 = ssl.wrap

local C, Cs, P, R, S          = lpeg.C, lpeg.Cs, lpeg.P, lpeg.R, lpeg.S
local lpegmatch               = lpeg.match
local urlescaper              = lpeg.patterns.urlescaper
local urlsplitter             = lpeg.patterns.urlsplitter
local rfc4180splitter         = utilities.parsers.rfc4180splitter ()

local error, warn, info

if luatexbase and luatexbase.provides_module then
  error, warn, info = luatexbase.provides_module(spreadsheet.module_info)
else
  kpse.set_program_name "luatex"
  error, warn, info = texiowrite_nl, texiowrite_nl, texiowrite_nl
end

-----------------------------------------------------------------------
---                       connection handling
-----------------------------------------------------------------------

local ssl_parameters = {
  mode      = "client",
  protocol  = "tlsv1_2",
  --protocol  = "sslv3",
  verify    = "none",
  options   = "all",
}

local http_302            = [[HTTP/1.1 302 Moved Temporarily]]
local http_200            = [[HTTP/1.1 200 OK]]

local p_restof            = (1 - P(-1))^1 * P(-1)
local p_location          = P"Location: "   * C(p_restof)
local p_setcookie         = P"Set-Cookie: " * C(p_restof)
local p_http_header       = C((R("az", "AZ") + P"-")^1 * P": " * p_restof)
local semicolon           = P";"
local p_cookie            = C((1 - semicolon)^1) --- ignore attributes

local tpl_GET             = "GET %s HTTP/1.1"
local tpl_HEAD            = "HEAD %s HTTP/1.1"
local header_Host         = "Host: %s"
local header_User_Agent   = "User-Agent: hackish CSV retrieval for LuaTeX"
local header_Accept       = "Accept: */*"
local header_Connection   = "Connection: Keep-Alive"
local header_Cookie       = "Cookie: %s"
----- header_Referer      = "Referer: %s"

local get_ssl_connection = function (hostname)
  --- open tcp socket
  local conn = sockettcp ()
  conn:connect (hostname, 443)

  --- envelope connection in ssl
  conn = sslwrap (conn, ssl_parameters)
  conn:dohandshake ()
  return conn
end

local make_request = function (resource, hostname, from, cookies)
  local req = { }

  --resource = lpegmatch (urlescaper, resource)

  --req[#req + 1] = string.format (tpl_HEAD, resource)
  req[#req + 1] = stringformat (tpl_GET, resource)
  req[#req + 1] = header_User_Agent
  req[#req + 1] = stringformat (header_Host, hostname)
  req[#req + 1] = header_Accept
  req[#req + 1] = header_Connection

  if cookies and next (cookies) then
    req[#req + 1] = stringformat (header_Cookie,
                                  tableconcat (cookies, "; "))
  end

  return tableconcat (req, "\n") .. "\n\n"
end

local max_redirects = 10

local resolve_indirection = function (uri)

  local from, conn, hostname
  local cookies     = { }
  local cnt         = 0 -- count redirects
  local components  = lpegmatch (urlsplitter, uri)

  while uri and cnt <= max_redirects do

    local req, line, err, redirect

    if not conn then
      hostname  = components [2]
      conn      = get_ssl_connection (hostname)
    end

    local resource = stringformat ([[/%s?%s]],
                                   components [3],
                                   components [4])

    local request = make_request (resource, hostname, from, cookies)

    local sent, err, last = conn:send (request)
    if not sent then
      warn ("> error; bytes sent:", last)
      warn "> retrying ... "
      local sent, err, last = conn:send (request, last)
      if not sent then
        warn ("> failed, aborting")
        return
      end
    end

    line, err, x, y = conn:receive ()
    --info (stringformat (">>> response=%q error=%q", line, err or "<none>"))

    if err then
      conn:close ()
      return
    end

    local found       = line == http_200
    local keepalive   = false

    while line do
      redirect = lpegmatch (p_location,  line) or redirect

      local cookie = lpegmatch (p_setcookie, line)
      if cookie then
        cookie = lpegmatch (p_cookie, cookie)
        cookies [#cookies + 1] = cookie
      end

      if line == header_Connection then
        keepalive = true
      end

      line, err = conn:receive ()
      if string.is_empty (line) then --- end of header
        line = nil
      end
    end --- while line

    if found then
      local data
      line, err = conn:receive ()
      if line then
        local bytes = tonumber (line, 16)
        if bytes then
          data = conn:receive (bytes)
        end
      end
      return uri, data
    end

    from    = uri
    uri     = redirect

    cnt = cnt + 1

    components = lpegmatch (urlsplitter, uri)

    if keepalive == false or hostname ~= components [2] then
      conn:close ()
      conn = nil
      collectgarbage "collect"
    end
  end -- while uri
end

-----------------------------------------------------------------------
---                          url handling
-----------------------------------------------------------------------

local ampersand     = P"&"
local output        = P"output=" * ((1 - ampersand)^1 / "csv")
local p_output      = (1 - output)^0 * output
local s_output      = Cs((output + 1)^0)

local rewrite_spreadsheet_uri = function (uri)

  info "Generating URL to CSV data."

  if not uri then
    return false
  end

  --- check if the uri already contains an output parameter

  if lpegmatch (p_output, uri) then

    --- if so, replace all occurrences with “csv” as argument

    return lpegmatch (s_output, uri)
  end

  --- else, append the desired parameter

  return uri .. [[&output=csv]]
end

local get_raw_doc = function (curi, force)

  info (stringformat ("Retrieving URI %q.", curi))

  local hash      = md5sumhexa (curi)
  local writable  = getwritablepath ("spreadsheet", "")
  local cachefile = writable .. "/" .. hash

  if not force and lfsisfile (cachefile) then
    local data = ioloaddata (cachefile)
    info (stringformat ("Spreadsheet (%d bytes) found in cache.",
                        #data))
    return "<cache>", data
  end

  local resolved, data = resolve_indirection (curi)

  if not resolved then
    info "Failed to resolve URI, sorry!"
    return nil, nil
  end

  info (stringformat ("Found at %q (%d bytes).",
                      resolved, #data))

  iosavedata (cachefile, data)

  info (stringformat ("Spreadsheet stored in cache at %q.",
                      cachefile))

  return resolved, data
end

-----------------------------------------------------------------------
---                         csv extraction
-----------------------------------------------------------------------

local extract_data = function (raw)
  local parsed = rfc4180splitter (raw)

  if not parsed then
    info "Cannot parse CSV file."
  end

  return parsed
end

-----------------------------------------------------------------------
--- latex writer
-----------------------------------------------------------------------

--- we consider the longest row only when making a spec

local colspec = {
  center   = "c",
  left     = "l",
  right    = "r",
  default  = "l",
}

local make_tablespec = function (rows, options)

  local align   = options.center and "center"
               or options.left   and "left"
               or options.right  and "right"
               or "default"

  local longest = 0

  for i = 1, #rows do
    local len = #rows [i]
    if len > longest then
      longest = len
    end
  end

  return longest, stringrep (colspec [align], longest)
end

local make_row = function (row, n)
  local acc = { }
  local i   = 1

  while i <= n do
    local cell = row [i]
    if cell then
      acc [#acc + 1] = cell
    else
      acc [#acc + 1] = "" -- fill up empty cells
    end
    i = i + 1
  end

  return tableconcat (acc, "  &  ") .. [[  \\]]
end

local starttable  = [[\begin {tabular} {%s}]]
local stoptable   = [[\end {tabular}]]

local tabular_of = function (data, options)
  local acc             = { }
  local nrows           = #data
  local ncols, tspec    = make_tablespec (data, options)

  acc [#acc + 1] = stringformat (starttable, tspec)

  for i = 1, nrows do
    acc [#acc + 1] = make_row (data [i], nrows)
  end

  acc [#acc + 1] = stoptable

  if texsprint then
    if options.dump then
      texiowrite_nl (tableconcat (acc, "\n"))
    end
    texsprint (unpack (acc))
  else
    texiowrite_nl (tableconcat (acc, "\n"))
  end

  return true
end

-----------------------------------------------------------------------
---                         option handler
-----------------------------------------------------------------------

local commasplitter = lpeg.splitat ","

local handle_options = function (raw)
  if raw == "" then
    return { }
  end

  local options = { lpegmatch (commasplitter, raw) }
  return tabletohash (options)
end

-----------------------------------------------------------------------
---                          main handler
-----------------------------------------------------------------------

local urihandler = function (rawoptions, uri)

  local options = handle_options (rawoptions)
  local curi    = rewrite_spreadsheet_uri (uri)

  if not curi then
    return false
  end

  local resolved, raw = get_raw_doc (curi, options.force)

  if not resolved then
    return false
  end

  local data = extract_data (raw)

  if not data then
    return false
  end

  return tabular_of (data, options)
end

packagedata.spreadsheet.urihandler = urihandler

--- test:
--- urihandler [[https://docs.google.com/spreadsheet/ccc?key=0Amykmqr4Of-MdEVIUUcyYld3WTJhZnJHRkgwSF9CaUE&usp=sharing]]

if not texsprint then --- running as script
  if arg [1] then
    return urihandler ("", arg [1])
  end
end