%-*-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 %%% %%% MIT License %%% %%% Copyright (c) 2014-2017 Michael Truog %%% %%% Permission is hereby granted, free of charge, to any person obtaining a %%% copy of this software and associated documentation files (the "Software"), %%% to deal in the Software without restriction, including without limitation %%% the rights to use, copy, modify, merge, publish, distribute, sublicense, %%% and/or sell copies of the Software, and to permit persons to whom the %%% Software is furnished to do so, subject to the following conditions: %%% %%% The above copyright notice and this permission notice shall be included in %%% all copies or substantial portions of the Software. %%% %%% THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR %%% IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, %%% FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE %%% AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER %%% LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING %%% FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER %%% DEALINGS IN THE SOFTWARE. %%% %%% @author Michael Truog %%% @copyright 2014-2017 Michael Truog %%% @version 1.7.1 {@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 any supported %% 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 :: #{cloudi_key_value:key() := cloudi_key_value:value()}. key_value_parse(RequestInfo) when is_binary(RequestInfo) -> text_pairs_binary_to_map(RequestInfo); key_value_parse(RequestInfo) -> cloudi_key_value:to_map(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_map_element([<<>>], Lookup) -> Lookup; text_pairs_binary_to_map_element([K, V | L], Lookup) -> case maps:find(K, Lookup) of {ok, [_ | _] = ListV} -> NewLookup = maps:put(K, ListV ++ [V], Lookup), text_pairs_binary_to_map_element(L, NewLookup); {ok, PreviousV} when is_binary(PreviousV) -> NewLookup = maps:put(K, [PreviousV, V], Lookup), text_pairs_binary_to_map_element(L, NewLookup); error -> text_pairs_binary_to_map_element(L, maps:put(K, V, Lookup)) end. text_pairs_binary_to_map(RequestInfo) -> L = binary:split(RequestInfo, <<0>>, [global]), text_pairs_binary_to_map_element(L, #{}).