1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
|
/**
* @file llhttpretrypolicy.h
* @brief Header for a retry policy class intended for use with http responders.
*
* $LicenseInfo:firstyear=2013&license=viewerlgpl$
* Second Life Viewer Source Code
* Copyright (C) 2013, Linden Research, Inc.
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation;
* version 2.1 of the License only.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*
* Linden Research, Inc., 945 Battery Street, San Francisco, CA 94111 USA
* $/LicenseInfo$
*/
#include "llviewerprecompiledheaders.h"
#include "llhttpretrypolicy.h"
LLAdaptiveRetryPolicy::LLAdaptiveRetryPolicy(F32 min_delay, F32 max_delay, F32 backoff_factor, U32 max_retries):
mMinDelay(min_delay),
mMaxDelay(max_delay),
mBackoffFactor(backoff_factor),
mMaxRetries(max_retries),
mDelay(min_delay),
mRetryCount(0),
mShouldRetry(true)
{
}
bool LLAdaptiveRetryPolicy::getRetryAfter(const LLSD& headers, F32& retry_header_time)
{
return (headers.has(HTTP_IN_HEADER_RETRY_AFTER)
&& getSecondsUntilRetryAfter(headers[HTTP_IN_HEADER_RETRY_AFTER].asStringRef(), retry_header_time));
}
bool LLAdaptiveRetryPolicy::getRetryAfter(const LLCore::HttpHeaders *headers, F32& retry_header_time)
{
if (headers)
{
const std::string *retry_value = headers->find(HTTP_IN_HEADER_RETRY_AFTER.c_str());
if (retry_value &&
getSecondsUntilRetryAfter(*retry_value, retry_header_time))
{
return true;
}
}
return false;
}
void LLAdaptiveRetryPolicy::onFailure(S32 status, const LLSD& headers)
{
F32 retry_header_time;
bool has_retry_header_time = getRetryAfter(headers,retry_header_time);
onFailureCommon(status, has_retry_header_time, retry_header_time);
}
void LLAdaptiveRetryPolicy::onFailure(const LLCore::HttpResponse *response)
{
F32 retry_header_time;
const LLCore::HttpHeaders *headers = response->getHeaders();
bool has_retry_header_time = getRetryAfter(headers,retry_header_time);
onFailureCommon(response->getStatus().mType, has_retry_header_time, retry_header_time);
}
void LLAdaptiveRetryPolicy::onFailureCommon(S32 status, bool has_retry_header_time, F32 retry_header_time)
{
if (!mShouldRetry)
{
llinfos << "keep on failing" << llendl;
return;
}
if (mRetryCount > 0)
{
mDelay = llclamp(mDelay*mBackoffFactor,mMinDelay,mMaxDelay);
}
// Honor server Retry-After header.
// Status 503 may ask us to wait for a certain amount of time before retrying.
F32 wait_time = mDelay;
if (has_retry_header_time)
{
wait_time = retry_header_time;
}
if (mRetryCount>=mMaxRetries)
{
llinfos << "Too many retries " << mRetryCount << ", will not retry" << llendl;
mShouldRetry = false;
}
if (!isHttpServerErrorStatus(status))
{
llinfos << "Non-server error " << status << ", will not retry" << llendl;
mShouldRetry = false;
}
if (mShouldRetry)
{
llinfos << "Retry count " << mRetryCount << " should retry after " << wait_time << llendl;
mRetryTimer.reset();
mRetryTimer.setTimerExpirySec(wait_time);
}
mRetryCount++;
}
bool LLAdaptiveRetryPolicy::shouldRetry(F32& seconds_to_wait) const
{
if (mRetryCount == 0)
{
// Called shouldRetry before any failure.
seconds_to_wait = F32_MAX;
return false;
}
seconds_to_wait = mShouldRetry ? mRetryTimer.getRemainingTimeF32() : F32_MAX;
return mShouldRetry;
}
|
