{"id":1263,"date":"2019-08-19T13:26:03","date_gmt":"2019-08-19T13:26:03","guid":{"rendered":"https:\/\/www.ipcpu.com\/?p=1263"},"modified":"2019-11-20T01:52:07","modified_gmt":"2019-11-20T01:52:07","slug":"http-cache","status":"publish","type":"post","link":"https:\/\/c.ipcpu.com\/2019\/08\/http-cache\/","title":{"rendered":"\u4e00\u56fe\u770b\u61c2HTTP\u7f13\u5b58\u63a7\u5236\/\u6d4f\u89c8\u5668\u7f13\u5b58\u63a7\u5236"},"content":{"rendered":"

\u4e00\u56fe\u770b\u61c2HTTP\u7f13\u5b58\u63a7\u5236\/\u6d4f\u89c8\u5668\u7f13\u5b58\u63a7\u5236.md<\/p>\n

\u4e00\u3001\u5f15\u5165<\/h2>\n

\u4ece\u7f51\u4e0a\u770b\u5230\u4e00\u5f20\u56fe\uff0c\u89c9\u7740\u633a\u4e0d\u9519\u7684\uff0c\u62ff\u6765\u548c\u5927\u5bb6\u5206\u4eab\u3002\u5982\u4e0b\u3002<\/p>\n

\u4f46\u540e\u6765\u53d1\u73b0\uff0c\u8fd9\u5f20\u56fe\u4e00\u5f00\u59cb\u7684\u90e8\u5206\u5b58\u5728\u9519\u8bef\uff0c\u6240\u4ee5\u8fd8\u662f\u6574\u7406\u4e0b\u7f13\u5b58\u63a7\u5236\u7684\u5185\u5bb9\u3002<\/p>\n

\"\"<\/a> <\/p>\n

\u6d4f\u89c8\u5668\u7684\u7f13\u5b58\uff0c\u4e3b\u8981\u5206\u4e3a\u4e24\u79cd\uff1a<\/p>\n

\u5f3a\u7f13\u5b58 200 (from memory cache)\u548c200 (from disk cache)<\/p>\n

\u534f\u5546\u7f13\u5b58 304 (Not Modified)<\/p><\/blockquote>\n

\u4e8c\u3001\u5f3a\u7f13\u5b58<\/h2>\n

\u5982\u679c\u542f\u7528\u4e86\u5f3a\u7f13\u5b58\uff0c\u8bf7\u6c42\u8d44\u6e90\u65f6\u4e0d\u4f1a\u5411\u670d\u52a1\u5668\u53d1\u9001\u8bf7\u6c42\uff0c\u76f4\u63a5\u4ece\u7f13\u5b58\u4e2d\u8bfb\u53d6\u8d44\u6e90\uff0c\u5728chrome\u63a7\u5236\u53f0\u7684network\u4e2d\u770b\u5230\u8bf7\u6c42\u8fd4\u56de\u7684200\u72b6\u6001\u7801\uff0c\u5e76\u5728\u72b6\u6001\u7801\u7684\u540e\u9762\u8ddf\u7740from disk cache \u6216\u8005from memory cache\u5173\u952e\u5b57\u3002\u4e24\u8005\u7684\u5dee\u522b\u5728\u4e8e\u83b7\u53d6\u7f13\u5b58\u7684\u4f4d\u7f6e\u4e0d\u4e00\u6837\u3002<\/p>\n

\u5f3a\u7f13\u5b58\u7684\u63a7\u5236\u5934\u90e8\u662fCache-Control \u548c Expires<\/p>\n

Cache-Control\u662f http1.1 \u65f6\u51fa\u73b0\u7684header\u4fe1\u606f\uff0c\u4e3b\u8981\u662f\u5229\u7528\u8be5\u5b57\u6bb5\u7684max-age\u503c\u6765\u8fdb\u884c\u5224\u65ad\uff0c\u5b83\u662f\u4e00\u4e2a\u76f8\u5bf9\u65f6\u95f4\uff0c\u4f8b\u5982Cache-Control:max-age=3600\uff0c\u4ee3\u8868\u7740\u8d44\u6e90\u7684\u6709\u6548\u671f\u662f3600\u79d2\u3002<\/p>\n

Expires\u662fhttp1.0\u7684\u89c4\u8303\uff0c\u5b83\u7684\u503c\u662f\u4e00\u4e2a\u7edd\u5bf9\u65f6\u95f4\u7684GMT\u683c\u5f0f\u7684\u65f6\u95f4\u5b57\u7b26\u4e32\u3002\u6bd4\u5982 \uff1aexpires:Fri, 14 Apr 2017 10:47:02 GMT\u3002\u8fd9\u4e2a\u65f6\u95f4\u4ee3\u8868\u8fd9\u8fd9\u4e2a\u8d44\u6e90\u7684\u5931\u6548\u65f6\u95f4\uff0c\u53ea\u8981\u53d1\u9001\u8bf7\u6c42\u65f6\u95f4\u662f\u5728Expires\u4e4b\u524d\uff0c\u90a3\u4e48\u672c\u5730\u7f13\u5b58\u59cb\u7ec8\u6709\u6548\uff0c\u5219\u5728\u7f13\u5b58\u4e2d\u8bfb\u53d6\u6570\u636e\u3002<\/p>\n

\u5982\u679c\u540c\u65f6\u51fa\u73b0Cache-Control:max-age\u548cExpires\uff0c\u90a3\u4e48max-age\u4f18\u5148\u7ea7\u66f4\u9ad8\u3002<\/strong><\/p>\n

\u4e09\u3001\u534f\u5546\u7f13\u5b58<\/h2>\n

\u534f\u5546\u7f13\u5b58\u5c31\u662f\u7531\u670d\u52a1\u5668\u6765\u786e\u5b9a\u7f13\u5b58\u8d44\u6e90\u662f\u5426\u53ef\u7528\uff0c\u6240\u4ee5\u5ba2\u6237\u7aef\u4e0e\u670d\u52a1\u5668\u7aef\u8981\u901a\u8fc7\u67d0\u79cd\u6807\u8bc6\u6765\u8fdb\u884c\u901a\u4fe1\uff0c\u4ece\u800c\u8ba9\u670d\u52a1\u5668\u5224\u65ad\u8bf7\u6c42\u8d44\u6e90\u662f\u5426\u53ef\u4ee5\u7f13\u5b58\u8bbf\u95ee\uff0c\u8fd9\u4e3b\u8981\u6d89\u53ca\u5230\u4e0b\u9762\u4e24\u7ec4header\u5b57\u6bb5\u3002\u8fd9\u4e24\u7ec4\u642d\u6863\u90fd\u662f\u6210\u5bf9\u51fa\u73b0\u7684\uff0c\u5373\u7b2c\u4e00\u6b21\u8bf7\u6c42\u7684\u54cd\u5e94\u5934\u5e26\u4e0a\u67d0\u4e2a\u5b57\u6bb5\uff08Last-Modified\u6216\u8005Etag\uff09\uff0c\u5219\u540e\u7eed\u8bf7\u6c42\u5219\u4f1a\u5e26\u4e0a\u5bf9\u5e94\u7684\u8bf7\u6c42\u5b57\u6bb5\uff08If-Modified-Since\u6216\u8005If-None-Match\uff09\uff0c\u82e5\u54cd\u5e94\u5934\u6ca1\u6709Last-Modified\u6216\u8005Etag\u5b57\u6bb5\uff0c\u5219\u8bf7\u6c42\u5934\u4e5f\u4e0d\u4f1a\u6709\u5bf9\u5e94\u7684\u5b57\u6bb5\u3002<\/p>\n

\u901a\u8fc7\u8fd9\u4e24\u7ec4\u53c2\u6570\uff0c\u5982\u679c\u7b26\u5408\uff0c\u90a3\u4e48\u670d\u52a1\u5668\u5c31\u4f1a\u8fd4\u56de304\u72b6\u6001\u7801\u5e76\u5e26\u4e0a\u65b0\u7684response header\u901a\u77e5\u6d4f\u89c8\u5668\u4ece\u7f13\u5b58\u4e2d\u8bfb\u53d6\u8d44\u6e90\u3002<\/p>\n

3.1 ETag\/If-None-Match<\/h4>\n

\u4e0eLast-Modify\/If-Modify-Since\u4e0d\u540c\u7684\u662f\uff0cEtag\/If-None-Match\u8fd4\u56de\u7684\u662f\u4e00\u4e2a\u6821\u9a8c\u7801\uff08Apache\u4e2d\uff0cETag\u7684\u503c\uff0c\u9ed8\u8ba4\u662f\u5bf9\u6587\u4ef6\u7684\u7d22\u5f15\u8282\uff08INode\uff09\uff0c\u5927\u5c0f\uff08Size\uff09\u548c\u6700\u540e\u4fee\u6539\u65f6\u95f4\uff08MTime\uff09\u8fdb\u884cHash\u540e\u5f97\u5230\u7684\uff09\u3002ETag\u53ef\u4ee5\u4fdd\u8bc1\u6bcf\u4e00\u4e2a\u8d44\u6e90\u662f\u552f\u4e00\u7684\uff0c\u8d44\u6e90\u53d8\u5316\u90fd\u4f1a\u5bfc\u81f4ETag\u53d8\u5316\u3002\u670d\u52a1\u5668\u6839\u636e\u6d4f\u89c8\u5668\u4e0a\u9001\u7684If-None-Match\u503c\u6765\u5224\u65ad\u662f\u5426\u547d\u4e2d\u7f13\u5b58\u3002
\n\u4e0eLast-Modified\u4e0d\u4e00\u6837\u7684\u662f\uff0c\u5f53\u670d\u52a1\u5668\u8fd4\u56de304 Not Modified\u7684\u54cd\u5e94\u65f6\uff0c\u7531\u4e8eETag\u91cd\u65b0\u751f\u6210\u8fc7\uff0cresponse header\u4e2d\u8fd8\u4f1a\u628a\u8fd9\u4e2aETag\u8fd4\u56de\uff0c\u5373\u4f7f\u8fd9\u4e2aETag\u8ddf\u4e4b\u524d\u7684\u6ca1\u6709\u53d8\u5316\u3002<\/p>\n

3.2 Last-Modify\/If-Modify-Since<\/h4>\n

\u6d4f\u89c8\u5668\u7b2c\u4e00\u6b21\u8bf7\u6c42\u4e00\u4e2a\u8d44\u6e90\u7684\u65f6\u5019\uff0c\u670d\u52a1\u5668\u8fd4\u56de\u7684header\u4e2d\u4f1a\u52a0\u4e0aLast-Modify\uff0cLast-modify\u662f\u4e00\u4e2a\u65f6\u95f4\u6807\u8bc6\u8be5\u8d44\u6e90\u7684\u6700\u540e\u4fee\u6539\u65f6\u95f4\uff0c\u4f8b\u5982Last-Modify: Thu,31 Dec 2037 23:59:59 GMT\u3002
\n\u5f53\u6d4f\u89c8\u5668\u518d\u6b21\u8bf7\u6c42\u8be5\u8d44\u6e90\u65f6\uff0crequest\u7684\u8bf7\u6c42\u5934\u4e2d\u4f1a\u5305\u542bIf-Modify-Since\uff0c\u8be5\u503c\u4e3a\u7f13\u5b58\u4e4b\u524d\u8fd4\u56de\u7684Last-Modify\u3002\u670d\u52a1\u5668\u6536\u5230If-Modify-Since\u540e\uff0c\u6839\u636e\u8d44\u6e90\u7684\u6700\u540e\u4fee\u6539\u65f6\u95f4\u5224\u65ad\u662f\u5426\u547d\u4e2d\u7f13\u5b58\u3002
\n\u5982\u679c\u547d\u4e2d\u7f13\u5b58\uff0c\u5219\u8fd4\u56de304\uff0c\u5e76\u4e14\u4e0d\u4f1a\u8fd4\u56de\u8d44\u6e90\u5185\u5bb9\uff0c\u5e76\u4e14\u4e0d\u4f1a\u8fd4\u56deLast-Modify\u3002<\/p>\n

Last-Modified\u4e0eETag\u662f\u53ef\u4ee5\u4e00\u8d77\u4f7f\u7528\u7684\uff0c\u670d\u52a1\u5668\u4f1a\u4f18\u5148\u9a8c\u8bc1ETag\uff0c\u4e00\u81f4\u7684\u60c5\u51b5\u4e0b\uff0c\u624d\u4f1a\u7ee7\u7eed\u6bd4\u5bf9Last-Modified\uff0c\u6700\u540e\u624d\u51b3\u5b9a\u662f\u5426\u8fd4\u56de304\u3002<\/strong><\/p>\n

\u56db\u3001\u5e38\u89c1\u95ee\u9898<\/h2>\n

4.1 \u4e3a\u4ec0\u4e48\u8981\u6709Etag\uff1f<\/h4>\n

\u4f60\u53ef\u80fd\u4f1a\u89c9\u5f97\u4f7f\u7528Last-Modified\u5df2\u7ecf\u8db3\u4ee5\u8ba9\u6d4f\u89c8\u5668\u77e5\u9053\u672c\u5730\u7684\u7f13\u5b58\u526f\u672c\u662f\u5426\u8db3\u591f\u65b0\uff0c\u4e3a\u4ec0\u4e48\u8fd8\u9700\u8981Etag\u5462\uff1fHTTP1.1\u4e2dEtag\u7684\u51fa\u73b0\u4e3b\u8981\u662f\u4e3a\u4e86\u89e3\u51b3\u51e0\u4e2aLast-Modified\u6bd4\u8f83\u96be\u89e3\u51b3\u7684\u95ee\u9898\uff1a<\/p>\n

\u4e00\u4e9b\u6587\u4ef6\u4e5f\u8bb8\u4f1a\u5468\u671f\u6027\u7684\u66f4\u6539\uff0c\u4f46\u662f\u4ed6\u7684\u5185\u5bb9\u5e76\u4e0d\u6539\u53d8(\u4ec5\u4ec5\u6539\u53d8\u7684\u4fee\u6539\u65f6\u95f4)\uff0c\u8fd9\u4e2a\u65f6\u5019\u6211\u4eec\u5e76\u4e0d\u5e0c\u671b\u5ba2\u6237\u7aef\u8ba4\u4e3a\u8fd9\u4e2a\u6587\u4ef6\u88ab\u4fee\u6539\u4e86\uff0c\u800c\u91cd\u65b0GET\uff1b
\n\u67d0\u4e9b\u6587\u4ef6\u4fee\u6539\u975e\u5e38\u9891\u7e41\uff0c\u6bd4\u5982\u5728\u79d2\u4ee5\u4e0b\u7684\u65f6\u95f4\u5185\u8fdb\u884c\u4fee\u6539\uff0c(\u6bd4\u65b9\u8bf41s\u5185\u4fee\u6539\u4e86N\u6b21)\uff0cIf-Modified-Since\u80fd\u68c0\u67e5\u5230\u7684\u7c92\u5ea6\u662fs\u7ea7\u7684\uff0c\u8fd9\u79cd\u4fee\u6539\u65e0\u6cd5\u5224\u65ad(\u6216\u8005\u8bf4UNIX\u8bb0\u5f55MTIME\u53ea\u80fd\u7cbe\u786e\u5230\u79d2)\uff1b
\n\u67d0\u4e9b\u670d\u52a1\u5668\u4e0d\u80fd\u7cbe\u786e\u7684\u5f97\u5230\u6587\u4ef6\u7684\u6700\u540e\u4fee\u6539\u65f6\u95f4\u3002<\/p><\/blockquote>\n

4.2 \u5982\u679c\u4ec0\u4e48\u7f13\u5b58\u7b56\u7565\u90fd\u6ca1\u8bbe\u7f6e\uff0c\u90a3\u4e48\u6d4f\u89c8\u5668\u4f1a\u600e\u4e48\u5904\u7406\uff1f<\/h4>\n

\u5982\u679c\u4ec0\u4e48\u7f13\u5b58\u7b56\u7565\u90fd\u6ca1\u8bbe\u7f6e\uff0c\u6ca1\u6709Cache-Control\u4e5f\u6ca1\u6709Expires\uff0c\u5bf9\u4e8e\u8fd9\u79cd\u60c5\u51b5\uff0c\u6d4f\u89c8\u5668\u4f1a\u91c7\u7528\u4e00\u4e2a\u542f\u53d1\u5f0f\u7684\u7b97\u6cd5(LM-Factor)\uff0c\u901a\u5e38\u4f1a\u53d6\u54cd\u5e94\u5934\u4e2d\u7684 Date \u51cf\u53bb Last-Modified \u503c\u7684 10% \uff08\u4e0d\u540c\u7684\u6d4f\u89c8\u5668\u53ef\u80fd\u4e0d\u4e00\u6837\uff09\u4f5c\u4e3a\u7f13\u5b58\u65f6\u95f4\u3002<\/p>\n

\u4e94\u3001\u603b\u7ed3\u6210\u4e00\u5f20\u6b63\u786e\u7684\u56fe\u7247<\/h2>\n

\"\"<\/a><\/p>\n

\u53c2\u8003\u8d44\u6599<\/h2>\n

https:\/\/kebingzao.com\/2018\/07\/05\/browser-cache\/<\/a>
\nhttps:\/\/segmentfault.com\/a\/1190000005704489<\/a>
\nhttps:\/\/srtian96.gitee.io\/blog\/2018\/08\/16\/%E6%B5%85%E8%B0%88HTTP%E7%BC%93%E5%AD%98\/<\/a><\/p>\n

 <\/p>\n

<\/div>\n
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<\/div>\n<\/div>\n
\n
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<\/div>\n
<\/div>\n
<\/div>\n<\/div>\n

 <\/p>\n

\u6765\u81ea\u4e3a\u77e5\u7b14\u8bb0(Wiz)<\/a><\/div>\n

\u8f6c\u8f7d\u8bf7\u6ce8\u660e\uff1aIPCPU-\u7f51\u7edc\u4e4b\u8def<\/a> » \u4e00\u56fe\u770b\u61c2HTTP\u7f13\u5b58\u63a7\u5236\/\u6d4f\u89c8\u5668\u7f13\u5b58\u63a7\u5236<\/a><\/p>","protected":false},"excerpt":{"rendered":"

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