{"id":3320,"date":"2018-09-03T10:13:37","date_gmt":"2018-09-03T02:13:37","guid":{"rendered":"http:\/\/www.yewen.us\/blog\/?p=3320"},"modified":"2018-09-03T10:13:37","modified_gmt":"2018-09-03T02:13:37","slug":"python-decorator-lib","status":"publish","type":"post","link":"https:\/\/www.yewen.us\/blog\/2018\/09\/python-decorator-lib\/","title":{"rendered":"Python decorator \u5e93"},"content":{"rendered":"<p>\u4e0a\u4e2a\u6708\u5173\u4e8e Python \u7684 Decorator \u5199\u8fc7\u4e00\u7bc7 <a href=\"https:\/\/www.yewen.us\/blog\/2018\/05\/get-args-of-origin-function-in-python-decorator-chain\/\" rel=\"noopener\" target=\"_blank\">Python \u591a\u5c42 decorator \u5185\u83b7\u53d6\u539f\u59cb\u51fd\u6570\u53c2\u6570\u5b57\u5178<\/a>\uff0c\u540e\u6765\u718a\u63d0\u9192\u8fd9\u79cd\u6bd4\u8f83\u901a\u7528\u7684\u4e1c\u897f\u5e94\u8be5\u90fd\u4f1a\u6709\u73b0\u6210\u7684\u5e93\uff0c\u641c\u4e86\u4e0b\u679c\u7136\u6709 \u4e2a\u5e93\u5c31\u53eb <code>Decorator<\/code><\/p>\n<p>\u76f8\u5173\u7684\u9879\u76ee\u5730\u5740\u5728<\/p>\n<ul>\n<li><a href=\"https:\/\/pypi.org\/project\/decorator\/\" rel=\"noopener\" target=\"_blank\">https:\/\/pypi.org\/project\/decorator\/<\/a> PyPi \u4ed3\u5e93<\/li>\n<li><a href=\"https:\/\/github.com\/micheles\/decorator\" rel=\"noopener\" target=\"_blank\">https:\/\/github.com\/micheles\/decorator<\/a> \u9879\u76ee\u4e3b\u9875<\/li>\n<li><a href=\"http:\/\/decorator.readthedocs.io\/en\/latest\/\" rel=\"noopener\" target=\"_blank\">http:\/\/decorator.readthedocs.io\/en\/latest\/<\/a> \u6587\u6863\u5165\u53e3<\/li>\n<\/ul>\n<p>\u770b\u4e86\u4e0b\u6e90\u7801\uff0c\u4ed6\u6bd4\u4e4b\u524d\u6211\u7684\u505a\u6cd5\u66f4\u8fdb\u4e00\u6b65\uff0c\u76f4\u63a5\u628a\u8981\u4fee\u9970\u7684\u539f\u65b9\u6cd5\u7684\u540d\u5b57\u548c\u53c2\u6570\uff0c\u90fd\u626b\u4ee3\u7801\u89e3\u6790\u51fa\u6765\uff0c\u518d\u5230\u4e00\u4e2a\u89e3\u6790\u5668\u7684\u4e34\u65f6\u6587\u4ef6\u91cc\u539f\u6837\u5199\u4e00\u4e2a\u65b0\u7684\u65b9\u6cd5\uff0c\u5e76\u628a\u76f8\u5173\u9700\u8981\u590d\u5236\u7684\u53c2\u6570\u5c5e\u6027\u7b49\u90fd\u76f4\u63a5\u590d\u5236\u7ed9\u8fd9\u4e2a\u65b0\u65b9\u6cd5\uff0c\u8fd9\u4e2a\u65b0\u65b9\u6cd5\u518d\u8c03\u4fee\u9970\u65b9\u6cd5\uff0c\u5c31\u53ef\u4ee5\u66f4\u5b8c\u7f8e\u7684\u5b9e\u73b0\u5bf9\u5916\u754c\u900f\u660e<\/p>\n<p>\u4f8b\u5982\u8fd9\u6837\u7684\u4ee3\u7801<\/p>\n<pre class=\"brush: python; title: ; notranslate\" title=\"\">\r\ndef foo(x, y=2, *args, **kw):\r\n  print(x)\r\n\r\ndef dec(func):\r\n  def wrapper(*args, **kw):\r\n    print(&quot;called %s with %s, %s&quot; % (func.__name__, args, kw))\r\n    return func(*args, **kw)\r\n  return wrapper\r\n\r\nfoo = dec(foo)\r\n<\/pre>\n<p>\u5728\u7ecf\u8fc7\u4e86 <code>@decorator<\/code> \u540e\u4f1a\u53d8\u6210<\/p>\n<pre class=\"brush: python; title: ; notranslate\" title=\"\">\r\n_func = foo\r\n_caller = wrapper\r\n\r\nfoo = def foo(x, y=2, *args, **kw):\r\n  return _caller(_func)(x, y, *args, **kw)\r\n<\/pre>\n<p>\u53ea\u6709\u4e00\u4e9b\u6d89\u53ca\u5230 func_code \u5185\u5b58\u5730\u5740\u7684\u5730\u65b9\u624d\u53ef\u4ee5\u53d1\u73b0\u4e0d\u4e00\u6837<\/p>\n<p>\u679c\u7136\u8fd8\u662f\u6709\u5e93\u7528\u5e93\uff0c\u7edd\u5927\u90e8\u5206\u60c5\u51b5\u4eba\u5bb6\u8fd8\u662f\u5b9e\u73b0\u5f97\u66f4\u597d\uff0c\u5c31\u662f\u539f\u7406\u80fd\u4e0d\u80fd\u770b\u61c2\u4e86\u3002\u81ea\u5df1\u6298\u817e\u7684\u597d\u5904\u662f\u6b63\u5411\u63a8\u8fc7\u53bb\uff0c\u5751\u548c\u539f\u7406\u90fd\u6bd4\u8f83\u4e86\u89e3\uff0c\u800c\u53cd\u5411\u770b\u522b\u4eba\u7684\u4ee3\u7801\uff0c\u6709\u5f88\u591a\u5947\u5999\u7684\u5730\u65b9\u5148\u60f3\u660e\u767d\u4e3a\u4ec0\u4e48\u8981\u8003\u8651\u8fd9\u4e2a\u60c5\u51b5\uff0c\u4ee5\u53ca\u8fd9\u4e2a\u60c5\u51b5\u4e3a\u4ec0\u4e48\u8981\u8fd9\u6837\u5904\u7406\uff0c\u90fd\u9700\u8981\u82b1\u5f88\u4e45<\/p>\n<p>\u6700\u540e\u5c0f\u5410\u69fd\u4e00\u4e0b\uff0c\u5728 decorator \u5e93\u91cc\uff0c\u5982\u679c\u662f py3\uff0c<code>replace('return', 'return await')<\/code> \u771f\u7684\u6ca1\u95ee\u9898\uff1f\u5982\u679c\u6709\u4eba\u9017\u6bd4\u5199\u4e86\u4e2a <code>returnVal = xxx<\/code> \u4e0d\u5c31\u5d29\u4e86<\/p>\n","protected":false},"excerpt":{"rendered":"<p>\u4e0a\u4e2a\u6708\u5173\u4e8e Python \u7684 Decorator \u5199\u8fc7\u4e00\u7bc7 Python \u591a\u5c42 decorator \u5185\u83b7\u53d6\u539f\u59cb [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"jetpack_post_was_ever_published":false,"_jetpack_newsletter_access":"","_jetpack_dont_email_post_to_subs":false,"_jetpack_newsletter_tier_id":0,"_jetpack_memberships_contains_paywalled_content":false,"_jetpack_memberships_contains_paid_content":false,"footnotes":""},"categories":[7],"tags":[665,127],"class_list":["post-3320","post","type-post","status-publish","format-standard","hentry","category-tech-notes","tag-decorator","tag-python"],"jetpack_featured_media_url":"","jetpack_sharing_enabled":true,"jetpack_shortlink":"https:\/\/wp.me\/p4aR5e-Ry","_links":{"self":[{"href":"https:\/\/www.yewen.us\/blog\/wp-json\/wp\/v2\/posts\/3320","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.yewen.us\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.yewen.us\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.yewen.us\/blog\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.yewen.us\/blog\/wp-json\/wp\/v2\/comments?post=3320"}],"version-history":[{"count":4,"href":"https:\/\/www.yewen.us\/blog\/wp-json\/wp\/v2\/posts\/3320\/revisions"}],"predecessor-version":[{"id":3389,"href":"https:\/\/www.yewen.us\/blog\/wp-json\/wp\/v2\/posts\/3320\/revisions\/3389"}],"wp:attachment":[{"href":"https:\/\/www.yewen.us\/blog\/wp-json\/wp\/v2\/media?parent=3320"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.yewen.us\/blog\/wp-json\/wp\/v2\/categories?post=3320"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.yewen.us\/blog\/wp-json\/wp\/v2\/tags?post=3320"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}