pastebin scraping api

local http = require'socket.http'

local char_to_hex = function(c)
    return string.format("%%%02X", string.byte(c))
end

local function urlencode(url)
    if url == nil then
        return
  end
    url = url:gsub("\n", "\r\n")
    url = url:gsub("([^%w ])", char_to_hex)
    url = url:gsub(" ", "+")
    return url
end

local hex_to_char = function(x)
  return string.char(tonumber(x, 16))
end

local urldecode = function(url)
    if url == nil then
        return false
    end
    url = url:gsub("+", " ")
    url = url:gsub("%%(%x%x)", hex_to_char)
    return url
end

local function topost(t)
    local res = {}
    for k, v in pairs(t) do
        res[#res + 1] = k .. '=' .. v
    end
    return table.concat(res, '&')
end


local paste = {}
paste.url = 'http://pastebin.com/api/'


function paste:init(user, pass, dev)
    self.pastekeys  = {}
    self.pastenames = {}
    self.pastelist  = {}

    self.user    = user
    self.pass    = pass
    self.dev     = dev
    self.tupdate = 0

    local session, err = self:login(user, pass, dev)
    if not session then return nil, err end
    self.session = session

    return self
end

setmetatable(paste, {__call = paste.init})

function paste:login(user, pass, dev)
    local data, err, code = http.request(
        self.url .. 'api_login.php',
        topost{
            api_dev_key       = self.dev,
            api_user_name     = self.user,
            api_user_password = self.pass
        }
    )

    if not data then return nil, err end
    if data:lower():find('^bad') then
    return nil, data
    end
    return data
end

function paste:list(limit)
    self.pastekeys  = {}
    self.pastenames = {}
    self.pastelist  = {}
    limit = limit or 1000

    local data, err, code = http.request(
        self.url .. 'api_post.php',
        topost{
            api_dev_key       = self.dev,
            api_user_key      = self.session,
            api_results_limit = limit,
            api_option        = 'list'
        }
    )


    if not data then return nil, err end
    if data:lower():find('^bad') then
        return nil, data
    end

    if data:lower():find('^no pastes found') then
        return nil, data
    end

    local list = {}
    for info in data:gmatch('<paste>(.-)</paste>') do
        local o = {}
        for k, v in info:gmatch('<(.-)>(.-)</.->') do
        if k == 'paste_url' then v = v:gsub('^https', 'http') end
            o[k] = v
        end
        self.pastekeys[o.paste_key]         = o
        self.pastenames[o.paste_title]      = o
        self.pastelist[#self.pastelist + 1] = o
        list[#list + 1] = o
    end

    return list
end

function paste:remove(obj)
    if type(obj) ~= 'table' then
        return nil, 'table paste expected, got ' .. type(obj)
    end

    for i, v in pairs(self.pastelist) do
        if v == obj then
            table.remove(self.pastelist, i)
            break
        end
    end

    self.pastekeys[obj.paste_key]    = nil
    self.pastenames[obj.paste_title] = nil
end

function paste:get(p)
    self:update()

    local paste, err = self:__get(p)
    if not paste then return nil, err end

    local data, err, code = http.request(
        self.url .. 'api_raw.php',
        topost{
            api_dev_key       = self.dev,
            api_user_key      = self.session,
            api_paste_key     = paste.paste_key,
            api_option        = 'show_paste',
        }
    )

    if not data then return nil, err end

    if data:sub(1, 5):lower():find('^bad') then
        return nil, data
    end

    return data
end

function paste:__get(p)
    p = self.pastekeys[p] or self.pastenames[p] or self.pastelist[p]
    if not p then
        return nil, 'no paste ' .. tostring(p) .. ' found'
    end
    return p
end

function paste:update()
    if os.time() - self.tupdate > 60 then
        local list, err = self:list()
        if not list then return nil, err end
        self.tupdate = os.time()
    end
    return true
end

function paste:delete(pastekey)
    if not self.paste then
        local list, err = self:list()
        if not list then return nil, err end
        self.paste = list
    end

    local paste, err = self:__get(pastekey)

    if not paste then return nil, err end

    print(self.url .. 'api_post.php', self.dev, paste.paste_key)
    local data, err, code = http.request(
        self.url .. 'api_post.php',
        topost{
            api_dev_key       = self.dev,
            api_user_key      = self.session,
            api_paste_key     = paste.paste_key,
            api_option        = 'delete',
        }
    )

    if not data then return nil, err end
    if data:lower():find('^bad') then
        return nil, data
    end

    return data
end

function paste:deleteByName(name)
    if not self.paste then
    local list, err = self:list()
    if not list then return nil, err end
    self.paste = list
    end

    local paste = self.paste[name]
    if not paste then return nil, 'Paste ' .. tostring(name) .. ' not exists' end

    print(self.url .. 'api_post.php', self.dev, paste.paste_key)
    local data, err, code = http.request(
        self.url .. 'api_post.php',
        topost{
            api_dev_key       = self.dev,
            api_user_key      = self.session,
            api_paste_key     = paste.paste_key,
            api_option        = 'delete',
        }
    )

    if not data then return nil, err end
    if data:lower():find('^bad') then
        return nil, data
    end

    return data
end

function paste:create(name, text, priv, lang, expire)
    if not name then return nil, 'name expected' end
    if not text then return nil, 'text expected' end
    local private;
    private = (priv == 'private'  or priv == 2) and 2
    private = (priv == 'unlisted' or priv == 1) and 1
    private = private or 0

    lang   = lang   or ''
    expire = expire or 'N'

    local data, err, code = http.request(
        self.url .. 'api_post.php',
        topost{
            api_dev_key           = self.dev,
            api_user_key          = self.session,
            api_paste_private     = private,
            api_paste_name        = urlencode(name),
            api_paste_expire_date = expire,
            api_paste_code        = urlencode(text),
            api_paste_format      = lang:lower():gsub('[^%w]', ''),
            api_option            = 'paste'
        }
    )

    self:list()
    if not data then return nil, err end
    if data:lower():find('^bad') then
        return nil, data
    end

    return data
end

if not ... then
    -- this is pastebin account for testing
    local login     = 'tpastebin'
    local password  = 'Qwerty!@#'
    local userkey   = '6de6c9893865973c05158d7436c2e62c'
    local pastename = 'test api paste'
    local pastecode = '{yoyo = \'123\'}'

    print('KEY:',    paste:init(login, password, userkey))
    print('CREATE:', paste:create(pastename, pastecode, 1, 'lua'))
    print('GET:',    paste:get(pastename))
    print('DELETE:', paste:delete(pastename))
    print('LIST:',   paste:list())
end

return paste