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
|
// Copyright Epic Games, Inc. All Rights Reserved.
#pragma once
#include <zencore/stats.h>
#include <zenhttp/httpserver.h>
#include "monitoring/httpstats.h"
#include "monitoring/httpstatus.h"
#include <memory>
namespace spdlog {
class logger;
}
namespace zen {
class CasStore;
class CidStore;
class CbObjectView;
class ScrubContext;
class UpstreamCache;
class ZenCacheStore;
enum class CachePolicy : uint32_t;
/**
* Structured cache service. Imposes constraints on keys, supports blobs and
* structured values
*
* Keys are structured as:
*
* {BucketId}/{KeyHash}
*
* Where BucketId is a lower-case alphanumeric string, and KeyHash is a 40-character
* hexadecimal sequence. The hash value may be derived in any number of ways, it's
* up to the application to pick an approach.
*
* Values may be structured or unstructured. Structured values are encoded using Unreal
* Engine's compact binary encoding (see CbObject)
*
* Additionally, attachments may be addressed as:
*
* {BucketId}/{KeyHash}/{PayloadHash}
*
* Where the two initial components are the same as for the main endpoint
*
* The storage strategy is as follows:
*
* - Structured values are stored in a dedicated backing store per bucket
* - Unstructured values and attachments are stored in the CAS pool
*
*/
class HttpStructuredCacheService : public HttpService, public IHttpStatsProvider, public IHttpStatusProvider
{
public:
HttpStructuredCacheService(ZenCacheStore& InCacheStore,
CidStore& InCidStore,
HttpStatsService& StatsService,
HttpStatusService& StatusService,
std::unique_ptr<UpstreamCache> UpstreamCache);
~HttpStructuredCacheService();
virtual const char* BaseUri() const override;
virtual void HandleRequest(zen::HttpServerRequest& Request) override;
void Flush();
void Scrub(ScrubContext& Ctx);
private:
struct CacheRef
{
std::string BucketSegment;
IoHash HashKey;
IoHash PayloadId;
};
struct CacheStats
{
std::atomic_uint64_t HitCount{};
std::atomic_uint64_t UpstreamHitCount{};
std::atomic_uint64_t MissCount{};
};
[[nodiscard]] bool ValidateKeyUri(zen::HttpServerRequest& Request, CacheRef& OutRef);
void HandleCacheRecordRequest(zen::HttpServerRequest& Request, const CacheRef& Ref, CachePolicy Policy);
void HandleGetCacheRecord(zen::HttpServerRequest& Request, const CacheRef& Ref, CachePolicy Policy);
void HandlePutCacheRecord(zen::HttpServerRequest& Request, const CacheRef& Ref, CachePolicy Policy);
void HandleCachePayloadRequest(zen::HttpServerRequest& Request, const CacheRef& Ref, CachePolicy Policy);
void HandleGetCachePayload(zen::HttpServerRequest& Request, const CacheRef& Ref, CachePolicy Policy);
void HandlePutCachePayload(zen::HttpServerRequest& Request, const CacheRef& Ref, CachePolicy Policy);
void HandleRpcRequest(zen::HttpServerRequest& Request);
void HandleRpcGetCacheRecords(zen::HttpServerRequest& Request, CbObjectView BatchRequest);
void HandleRpcGetCachePayloads(zen::HttpServerRequest& Request, CbObjectView BatchRequest);
void HandleCacheBucketRequest(zen::HttpServerRequest& Request, std::string_view Bucket);
virtual void HandleStatsRequest(zen::HttpServerRequest& Request) override;
virtual void HandleStatusRequest(zen::HttpServerRequest& Request) override;
spdlog::logger& Log() { return m_Log; }
spdlog::logger& m_Log;
ZenCacheStore& m_CacheStore;
HttpStatsService& m_StatsService;
HttpStatusService& m_StatusService;
CidStore& m_CidStore;
std::unique_ptr<UpstreamCache> m_UpstreamCache;
uint64_t m_LastScrubTime = 0;
metrics::OperationTiming m_HttpRequests;
metrics::OperationTiming m_UpstreamGetRequestTiming;
CacheStats m_CacheStats;
};
} // namespace zen
|