%-*-Mode:erlang;coding:utf-8;tab-width:4;c-basic-offset:4;indent-tabs-mode:()-*- % ex: set ft=erlang fenc=utf-8 sts=4 ts=4 sw=4 et nomod: %%% %%%------------------------------------------------------------------------ %%% @doc %%% ==CloudI RequestInfo Creation and Parsing== %%% RequestInfo is used for request meta-data which is normally %%% key/value pairs that describe the context of the service request %%% (e.g., HTTP header names and values for a HTTP request). The encoding %%% provided below is a basic format for textual key/value data %%% (i.e., neither the key or value should contain a null character, '\0') %%% which is easily parsed in any programming language and is referred to as %%% the 'text_pairs' format. It is valid to have multiple entries for the %%% same key within the RequestInfo data. A key must be of size 1 or greater %%% (`<<>>' will never exist as a key in text_pairs data). %%% %%% The ResponseInfo data is normally service request response meta-data %%% (providing the response equivalent of RequestInfo for a request) %%% and can utilize the same functions below. %%% %%% These module functions provide Erlang serialization of the 'text_pairs' %%% format for use with the cloudi_key_value module. %%% @end %%% %%% BSD LICENSE %%% %%% Copyright (c) 2014-2015, Michael Truog %%% All rights reserved. %%% %%% Redistribution and use in source and binary forms, with or without %%% modification, are permitted provided that the following conditions are met: %%% %%% * Redistributions of source code must retain the above copyright %%% notice, this list of conditions and the following disclaimer. %%% * Redistributions in binary form must reproduce the above copyright %%% notice, this list of conditions and the following disclaimer in %%% the documentation and/or other materials provided with the %%% distribution. %%% * All advertising materials mentioning features or use of this %%% software must display the following acknowledgment: %%% This product includes software developed by Michael Truog %%% * The name of the author may not be used to endorse or promote %%% products derived from this software without specific prior %%% written permission %%% %%% THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND %%% CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, %%% INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES %%% OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE %%% DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR %%% CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, %%% SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, %%% BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR %%% SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS %%% INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, %%% WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING %%% NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE %%% OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH %%% DAMAGE. %%% %%% @author Michael Truog %%% @copyright 2014-2015 Michael Truog %%% @version 1.5.1 {@date} {@time} %%%------------------------------------------------------------------------ -module(cloudi_request_info). -author('mjtruog [at] gmail (dot) com'). %% external interface -export([key_value_new/1, key_value_append/2, key_value_parse/1]). -include("cloudi_core_i_constants.hrl"). %%%------------------------------------------------------------------------ %%% External interface functions %%%------------------------------------------------------------------------ %%------------------------------------------------------------------------- %% @doc %% ===New RequestInfo key/value data.=== %% RequestInfo is meant to contain key/value pairs that is request %% meta-data. Create the binary RequestInfo data with a list of pairs or %% a dict data structure. %% @end %%------------------------------------------------------------------------- -spec key_value_new(RequestInfo :: cloudi_key_value:key_values()) -> Result :: binary(). key_value_new(RequestInfo) -> text_pairs_list_to_binary(cloudi_key_value:to_list(RequestInfo)). %%------------------------------------------------------------------------- %% @doc %% ===Append RequestInfo key/value data.=== %% Use the same binary format. %% @end %%------------------------------------------------------------------------- -spec key_value_append(RequestInfo :: cloudi_key_value:key_values(), Existing :: binary()) -> Result :: binary(). key_value_append(RequestInfo, <<>>) -> key_value_new(RequestInfo); key_value_append(RequestInfo, <> = Existing) when TextPairs /= 0 -> Suffix = key_value_new(RequestInfo), <>. %%------------------------------------------------------------------------- %% @doc %% ===Parse RequestInfo key/value data.=== %% RequestInfo is meant to contain key/value pairs that is request %% meta-data. %% @end %%------------------------------------------------------------------------- -spec key_value_parse(RequestInfo :: binary() | cloudi_key_value:key_values()) -> Result :: dict_proxy(cloudi_key_value:key(), cloudi_key_value:value()). key_value_parse(RequestInfo) when is_binary(RequestInfo) -> text_pairs_binary_to_dict(RequestInfo); key_value_parse(RequestInfo) -> cloudi_key_value:to_dict(RequestInfo). %%%------------------------------------------------------------------------ %%% Private functions %%%------------------------------------------------------------------------ text_pairs_key_to_binary(K) when is_binary(K) -> K; text_pairs_key_to_binary([H | _] = K) when is_integer(H) -> erlang:list_to_binary(K); text_pairs_key_to_binary(K) when is_atom(K) -> erlang:atom_to_binary(K, utf8). text_pairs_value_to_binary(V) when is_binary(V) -> V; text_pairs_value_to_binary(V) when is_list(V) -> erlang:iolist_to_binary(V); text_pairs_value_to_binary(V) when is_atom(V) -> erlang:atom_to_binary(V, utf8); text_pairs_value_to_binary(V) -> cloudi_string:term_to_binary(V). text_pairs_list_to_binary_element([] = L) -> L; text_pairs_list_to_binary_element([{K, V} | L]) -> BinaryK = text_pairs_key_to_binary(K), % a text_pairs key must be of size 1 or greater <> = BinaryK, true = TextPairs /= 0, BinaryV = text_pairs_value_to_binary(V), [[BinaryK, 0, BinaryV, 0] | text_pairs_list_to_binary_element(L)]. text_pairs_list_to_binary(L) -> erlang:iolist_to_binary(text_pairs_list_to_binary_element(L)). text_pairs_binary_to_dict_element([<<>>], Lookup) -> Lookup; text_pairs_binary_to_dict_element([K, V | L], Lookup) -> case dict:find(K, Lookup) of {ok, [_ | _] = ListV} -> NewLookup = dict:store(K, ListV ++ [V], Lookup), text_pairs_binary_to_dict_element(L, NewLookup); {ok, PreviousV} when is_binary(PreviousV) -> NewLookup = dict:store(K, [PreviousV, V], Lookup), text_pairs_binary_to_dict_element(L, NewLookup); error -> text_pairs_binary_to_dict_element(L, dict:store(K, V, Lookup)) end. text_pairs_binary_to_dict(RequestInfo) -> L = binary:split(RequestInfo, <<0>>, [global]), text_pairs_binary_to_dict_element(L, dict:new()).