{"id":207155,"date":"2025-07-08T10:49:27","date_gmt":"2025-07-08T02:49:27","guid":{"rendered":"https:\/\/server.hk\/cnblog\/207155\/"},"modified":"2025-07-08T10:49:27","modified_gmt":"2025-07-08T02:49:27","slug":"%e5%a6%82%e4%bd%95%e5%a4%84%e7%90%86%e5%8d%95%e4%be%8b%e4%bb%85%e4%b8%80%e6%ac%a1%e7%9a%84%e9%94%99%e8%af%af","status":"publish","type":"post","link":"https:\/\/server.hk\/cnblog\/207155\/","title":{"rendered":"\u5982\u4f55\u5904\u7406\u5355\u4f8b\u4ec5\u4e00\u6b21\u7684\u9519\u8bef"},"content":{"rendered":"

<\/b> <\/p>\n

\u5f53\u524d\u4f4d\u7f6e\uff1a ><\/span> ><\/span> ><\/span> ><\/span> \u5982\u4f55\u5904\u7406\u5355\u4f8b\u4ec5\u4e00\u6b21\u7684\u9519\u8bef<\/span><\/p>\n

\u6765\u6e90\uff1astackoverflow<\/span>
\n2024-04-20 14:09:36<\/span>
\n<\/i>0\u6d4f\u89c8<\/span>
\n<\/i>\u6536\u85cf<\/span> <\/p>\n

\u54c8\u55bd\uff01\u4eca\u5929\u5fc3\u8840\u6765\u6f6e\u7ed9\u5927\u5bb6\u5e26\u6765\u4e86\u300a\u5982\u4f55\u5904\u7406\u5355\u4f8b\u4ec5\u4e00\u6b21\u7684\u9519\u8bef\u300b<\/span>\uff0c\u60f3\u5fc5\u5927\u5bb6\u5e94\u8be5\u5bf9Golang<\/span>\u90fd\u4e0d\u964c\u751f\u5427\uff0c\u90a3\u4e48\u9605\u8bfb\u672c\u6587\u5c31\u90fd\u4e0d\u4f1a\u5f88\u56f0\u96be\uff0c\u4ee5\u4e0b\u5185\u5bb9\u4e3b\u8981\u6d89\u53ca\u5230<\/span>\uff0c\u82e5\u662f\u4f60\u6b63\u5728\u5b66\u4e60Golang<\/span>\uff0c\u5343\u4e07\u522b\u9519\u8fc7\u8fd9\u7bc7\u6587\u7ae0~\u5e0c\u671b\u80fd\u5e2e\u52a9\u5230\u4f60\uff01<\/p>\n

\u95ee\u9898\u5185\u5bb9
\n <\/p>\n

\u5982\u4f55\u53ea\u5904\u7406\u4e00\u6b21\u5355\u4f8b\u9519\u8bef\uff1f<\/h1>\n

\u6211\u6709\u4e00\u4e2a\u5355\u4f8b\u670d\u52a1\uff0c\u5b83\u4ec5\u5728\u7b2c\u4e00\u6b21\u8c03\u7528\u65f6\u624d\u4f1a\u751f\u6210\u9519\u8bef\uff0c\u7136\u540e\u8fd4\u56de\u5df2\u521b\u5efa\u7684\u5b9e\u4f8b\u3002<\/p>\n

\u670d\u52a1\u5982\u4e0b\u6240\u793a\uff1a<\/p>\n

package data\n\nimport (\n    \"sync\"\n\n    \"gorm.io\/driver\/postgres\"\n    \"gorm.io\/gorm\"\n)\n\nvar (\n    databasesingleton *gorm.db\n    once              sync.once\n)\n\nfunc newdatabase() (*gorm.db, error) {\n    once.do(func() {\n        \/\/ ...\n        databasesingleton, err = gorm.open(postgres.open(connectionstring), config)\n        if err != nil {\n            return nil, err\n        }\n    })\n    return databasesingleton, nil\n}\n<\/pre>\n
\u95ee\u9898\u662f\u591a\u4e2a\u670d\u52a1\u4f7f\u7528 databasesingleton<\/code> \u4ee5\u4e0a\u5904\u7406\u9519\u8bef\uff0c\u8be5\u9519\u8bef\u53ea\u80fd\u53d1\u751f\u4e00\u6b21\u3002<\/p>\n
\u4f7f\u7528 databasesingleton<\/code> \u7684\u670d\u52a1\u5982\u4e0b\u6240\u793a\uff1a<\/p>\n
func NewServiceOne() (ServiceOne, error) {\n   database, err := NewDatabase()\n   \/\/ want omit this error handling\n   if err != nil {\n       return nil, err\n   }\n   return &serviceOne{database}, nil\n}\nfunc NewServiceTwo() (ServiceTwo, error) {\n   database, err := NewDatabase()\n   \/\/ want omit this error handling\n   if err != nil {\n       return nil, err\n   }\n   return &serviceTwo{database}, nil\n}\nfunc NewServiceThree() (ServiceThree, error) {\n   database, err := NewDatabase()\n   \/\/ want omit this error handling\n   if err != nil {\n       return nil, err\n   }\n   return &serviceThree{database}, nil\n}\n<\/pre>\n
\u662f\u5426\u6709\u4efb\u4f55\u65b9\u6cd5\u53ef\u4ee5\u7701\u7565\u6b64\u9519\u8bef\u5904\u7406\uff0c\u56e0\u4e3a err<\/code> \u53ea\u80fd\u751f\u6210\u4e00\u6b21\uff1f<\/h2>\n
 <\/p>\n
\u6b63\u786e\u7b54\u6848<\/h2>\n
 <\/p>\n
\u5982\u679c\u53d1\u751f\u9519\u8bef\uff08\u4ec5\u4e00\u6b21\uff09\uff0c\u60a8\u7684 databasesingleton<\/code> \u5c06\u4e0d\u4f1a\u88ab\u8bbe\u7f6e\u3002\u5728\u6240\u6709\u60c5\u51b5\u4e0b\u60a8\u90fd\u5e94\u8be5\u8fd4\u56de\u9519\u8bef\u3002<\/p>\n
\u5c3d\u7ba1\u8fd9\u4e0d\u662f\u60a8\u53ef\u4ee5\u505a\u7684\u4efb\u4f55\u4e8b\u60c5\uff08\u56e0\u4e3a\u7531\u4e8e\u4f7f\u7528\u4e86 sync.once<\/code>\uff0c\u521d\u59cb\u5316 databasesingleton<\/code> \u7684\u5c1d\u8bd5\u4e0d\u4f1a\u91cd\u590d\uff09\uff0c\u60a8\u4e5f\u53ef\u4ee5\u505c\u6b62\u8be5\u5e94\u7528\u7a0b\u5e8f\u3002<\/p>\n
\u4e8b\u5b9e\u4e0a\uff0c\u63a8\u8fdf\u6b64\u521d\u59cb\u5316\u662f\u6ca1\u6709\u610f\u4e49\u7684\uff0c\u60a8\u53ef\u4ee5\u5728\u5305\u521d\u59cb\u5316\u671f\u95f4\u6267\u884c\u6b64\u64cd\u4f5c\uff0c\u5982\u679c\u5931\u8d25\u5219\u7ec8\u6b62\u3002\u5982\u679c\u6210\u529f\uff0c\u60a8\u53ef\u4ee5\u4f7f\u7528databasesingleton<\/code>\uff0c\u800c\u65e0\u9700\u68c0\u67e5\u521d\u59cb\u5316\u9519\u8bef\u3002<\/p>\n
\u6240\u4ee5\u53ea\u9700\u8fd9\u6837\u505a\uff1a<\/p>\n
var databasesingleton *gorm.db\n\nfunc init() {\n    var err error\n    databasesingleton, err = gorm.open(postgres.open(connectionstring), config)\n    if err != nil {\n        log.fatalf(\"failed to connect to db: %v\", err)\n    }\n}<\/pre>\n
newserviceone()<\/code> \u53ef\u80fd\u5982\u4e0b\u6240\u793a\uff1a<\/p>\n
func NewServiceOne() ServiceOne {\n   return &serviceOne{databaseSingleton}\n}<\/pre>\n
\u672c\u7bc7\u5173\u4e8e\u300a\u5982\u4f55\u5904\u7406\u5355\u4f8b\u4ec5\u4e00\u6b21\u7684\u9519\u8bef\u300b\u7684\u4ecb\u7ecd\u5c31\u5230\u6b64\u7ed3\u675f\u5566\uff0c\u4f46\u662f\u5b66\u65e0\u6b62\u5883\uff0c\u60f3\u8981\u4e86\u89e3\u5b66\u4e60\u66f4\u591a\u5173\u4e8eGolang\u7684\u76f8\u5173\u77e5\u8bc6\uff0c\u8bf7\u5173\u6ce8\u516c\u4f17\u53f7\uff01<\/p>\n","protected":false},"excerpt":{"rendered":"
\u5f53\u524d\u4f4d\u7f6e\uff1a > > ...<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[4925],"tags":[],"class_list":["post-207155","post","type-post","status-publish","format-standard","hentry","category-4925"],"_links":{"self":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/207155","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/comments?post=207155"}],"version-history":[{"count":0,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/207155\/revisions"}],"wp:attachment":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/media?parent=207155"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/categories?post=207155"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/tags?post=207155"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}