1%% 2%% Licensed to the Apache Software Foundation (ASF) under one 3%% or more contributor license agreements. See the NOTICE file 4%% distributed with this work for additional information 5%% regarding copyright ownership. The ASF licenses this file 6%% to you under the Apache License, Version 2.0 (the 7%% "License"); you may not use this file except in compliance 8%% with the License. You may obtain a copy of the License at 9%% 10%% http://www.apache.org/licenses/LICENSE-2.0 11%% 12%% Unless required by applicable law or agreed to in writing, 13%% software distributed under the License is distributed on an 14%% "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY 15%% KIND, either express or implied. See the License for the 16%% specific language governing permissions and limitations 17%% under the License. 18%% 19 20-module(thrift_http_transport). 21 22-behaviour(thrift_transport). 23 24%% API 25-export([new/2, new/3]). 26 27%% thrift_transport callbacks 28-export([write/2, read/2, flush/1, close/1]). 29 30-record(http_transport, {host, % string() 31 path, % string() 32 read_buffer, % iolist() 33 write_buffer, % iolist() 34 http_options, % see http(3) 35 extra_headers % [{str(), str()}, ...] 36 }). 37-type state() :: #http_transport{}. 38-include("thrift_transport_behaviour.hrl"). 39 40new(Host, Path) -> 41 new(Host, Path, _Options = []). 42 43%%-------------------------------------------------------------------- 44%% Options include: 45%% {http_options, HttpOptions} = See http(3) 46%% {extra_headers, ExtraHeaders} = List of extra HTTP headers 47%%-------------------------------------------------------------------- 48new(Host, Path, Options) -> 49 State1 = #http_transport{host = Host, 50 path = Path, 51 read_buffer = [], 52 write_buffer = [], 53 http_options = [], 54 extra_headers = []}, 55 ApplyOption = 56 fun 57 ({http_options, HttpOpts}, State = #http_transport{}) -> 58 State#http_transport{http_options = HttpOpts}; 59 ({extra_headers, ExtraHeaders}, State = #http_transport{}) -> 60 State#http_transport{extra_headers = ExtraHeaders}; 61 (Other, #http_transport{}) -> 62 {invalid_option, Other}; 63 (_, Error) -> 64 Error 65 end, 66 case lists:foldl(ApplyOption, State1, Options) of 67 State2 = #http_transport{} -> 68 thrift_transport:new(?MODULE, State2); 69 Else -> 70 {error, Else} 71 end. 72 73%% Writes data into the buffer 74write(State = #http_transport{write_buffer = WBuf}, Data) -> 75 {State#http_transport{write_buffer = [WBuf, Data]}, ok}. 76 77%% Flushes the buffer, making a request 78flush(State = #http_transport{host = Host, 79 path = Path, 80 read_buffer = Rbuf, 81 write_buffer = Wbuf, 82 http_options = HttpOptions, 83 extra_headers = ExtraHeaders}) -> 84 case iolist_to_binary(Wbuf) of 85 <<>> -> 86 %% Don't bother flushing empty buffers. 87 {State, ok}; 88 WBinary -> 89 {ok, {{_Version, 200, _ReasonPhrase}, _Headers, Body}} = 90 httpc:request(post, 91 {"http://" ++ Host ++ Path, 92 [{"User-Agent", "Erlang/thrift_http_transport"} | ExtraHeaders], 93 "application/x-thrift", 94 WBinary}, 95 HttpOptions, 96 [{body_format, binary}]), 97 98 State1 = State#http_transport{read_buffer = [Rbuf, Body], 99 write_buffer = []}, 100 {State1, ok} 101 end. 102 103close(State) -> 104 {State, ok}. 105 106read(State = #http_transport{read_buffer = RBuf}, Len) when is_integer(Len) -> 107 %% Pull off Give bytes, return them to the user, leave the rest in the buffer. 108 Give = min(iolist_size(RBuf), Len), 109 case iolist_to_binary(RBuf) of 110 <<Data:Give/binary, RBuf1/binary>> -> 111 Response = {ok, Data}, 112 State1 = State#http_transport{read_buffer=RBuf1}, 113 {State1, Response}; 114 _ -> 115 {State, {error, 'EOF'}} 116 end. 117