1// Copyright (c) 2011 The Chromium Authors. All rights reserved.
2// Use of this source code is governed by a BSD-style license that can be
3// found in the LICENSE file.
4
5// ProxyScriptFetcher is an async interface for fetching a proxy auto config
6// script. It is specific to fetching a PAC script; enforces timeout, max-size,
7// status code.
8
9#ifndef NET_PROXY_PROXY_SCRIPT_FETCHER_H_
10#define NET_PROXY_PROXY_SCRIPT_FETCHER_H_
11
12#include "base/strings/string16.h"
13#include "net/base/completion_callback.h"
14#include "net/base/net_export.h"
15
16class GURL;
17
18namespace net {
19
20class URLRequestContext;
21
22// Interface for downloading a PAC script. Implementations can enforce
23// timeouts, maximum size constraints, content encoding, etc..
24class NET_EXPORT_PRIVATE ProxyScriptFetcher {
25 public:
26  // Destruction should cancel any outstanding requests.
27  virtual ~ProxyScriptFetcher() {}
28
29  // Downloads the given PAC URL, and invokes |callback| on completion.
30  // Returns OK on success, otherwise the error code. If the return code is
31  // ERR_IO_PENDING, then the request completes asynchronously, and |callback|
32  // will be invoked later with the final error code.
33  // After synchronous or asynchronous completion with a result code of OK,
34  // |*utf16_text| is filled with the response. On failure, the result text is
35  // an empty string, and the result code is a network error. Some special
36  // network errors that may occur are:
37  //
38  //    ERR_TIMED_OUT         -- the fetch took too long to complete.
39  //    ERR_FILE_TOO_BIG      -- the response's body was too large.
40  //    ERR_PAC_STATUS_NOT_OK -- non-200 HTTP status code.
41  //    ERR_NOT_IMPLEMENTED   -- the response required authentication.
42  //
43  // If the request is cancelled (either using the "Cancel()" method or by
44  // deleting |this|), then no callback is invoked.
45  //
46  // Only one fetch is allowed to be outstanding at a time.
47  virtual int Fetch(const GURL& url, base::string16* utf16_text,
48                    const net::CompletionCallback& callback) = 0;
49
50  // Aborts the in-progress fetch (if any).
51  virtual void Cancel() = 0;
52
53  // Returns the request context that this fetcher uses to issue downloads,
54  // or NULL.
55  virtual URLRequestContext* GetRequestContext() const = 0;
56};
57
58}  // namespace net
59
60#endif  // NET_PROXY_PROXY_SCRIPT_FETCHER_H_
61