{"id":207020,"date":"2025-07-08T09:34:28","date_gmt":"2025-07-08T01:34:28","guid":{"rendered":"https:\/\/server.hk\/cnblog\/207020\/"},"modified":"2025-07-08T09:34:28","modified_gmt":"2025-07-08T01:34:28","slug":"func-init-%e4%b8%8e-func-main-%e7%94%a8%e4%ba%8e%e5%88%9d%e5%a7%8b%e5%8c%96-aws-lambda-%e5%a4%84%e7%90%86%e7%a8%8b%e5%ba%8f%e4%b8%ad%e7%9a%84%e5%85%a8%e5%b1%80%e7%8a%b6%e6%80%81","status":"publish","type":"post","link":"https:\/\/server.hk\/cnblog\/207020\/","title":{"rendered":"func init() \u4e0e func main() \u7528\u4e8e\u521d\u59cb\u5316 AWS Lambda \u5904\u7406\u7a0b\u5e8f\u4e2d\u7684\u5168\u5c40\u72b6\u6001"},"content":{"rendered":"

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

\u5f53\u524d\u4f4d\u7f6e\uff1a ><\/span> ><\/span> ><\/span> ><\/span> func init() \u4e0e func main() \u7528\u4e8e\u521d\u59cb\u5316 AWS Lambda \u5904\u7406\u7a0b\u5e8f\u4e2d\u7684\u5168\u5c40\u72b6\u6001<\/span><\/p>\n

\u6765\u6e90\uff1astackoverflow<\/span>
\n2024-04-19 15:33:33<\/span>
\n<\/i>0\u6d4f\u89c8<\/span>
\n<\/i>\u6536\u85cf<\/span> <\/p>\n

\u76ee\u524d\u4e0a\u5df2\u7ecf\u6709\u5f88\u591a\u5173\u4e8eGolang<\/span>\u7684\u6587\u7ae0\u4e86\uff0c\u81ea\u5df1\u5728\u521d\u6b21\u9605\u8bfb\u8fd9\u4e9b\u6587\u7ae0\u4e2d\uff0c\u4e5f\u89c1\u8bc6\u5230\u4e86\u5f88\u591a\u5b66\u4e60\u601d\u8def\uff1b\u90a3\u4e48\u672c\u6587\u300afunc init() \u4e0e func main() \u7528\u4e8e\u521d\u59cb\u5316 AWS Lambda \u5904\u7406\u7a0b\u5e8f\u4e2d\u7684\u5168\u5c40\u72b6\u6001\u300b<\/span>\uff0c\u4e5f\u5e0c\u671b\u80fd\u5e2e\u52a9\u5230\u5927\u5bb6\uff0c\u5982\u679c\u9605\u8bfb\u5b8c\u540e\u771f\u7684\u5bf9\u4f60\u5b66\u4e60Golang<\/span>\u6709\u5e2e\u52a9\uff0c\u6b22\u8fce\u52a8\u52a8\u624b\u6307\uff0c\u8bc4\u8bba\u7559\u8a00\u5e76\u5206\u4eab~<\/p>\n

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

\u67e5\u770b\u5b98\u65b9 go \u4e2d\u7684 aws lambda \u51fd\u6570\u5904\u7406\u7a0b\u5e8f<\/strong> \u6587\u6863\u4e2d\u7684\u4f7f\u7528\u5168\u5c40\u72b6\u6001<\/strong>\u90e8\u5206 https:\/\/docs.aws.amazon.com\/lambda\/latest\/dg\/golang-handler.html<\/p>\n

\u5efa\u8bae\u5728 func init()<\/code> \u4e2d\u521d\u59cb\u5316\u6240\u6709\u5168\u5c40\u72b6\u6001 \u5373\u6211\u4eec\u60f3\u8981\u5728\u591a\u4e2a lambda \u8c03\u7528\u4e4b\u95f4\u5171\u4eab\u7684\u4efb\u4f55\u5305\u7ea7\u522b\u53d8\u91cf\u90fd\u4f4d\u4e8e\u6b64\u5904\u3002<\/p>\n

\u6211\u7684\u7406\u89e3\u662f\uff0c\u6bcf\u6b21 lambda \u5bb9\u5668\u542f\u52a8\uff08\u5373\u51b7\u542f\u52a8\uff09\u65f6\u90fd\u4f1a\u5b8c\u6210\u4e00\u6b21\u521d\u59cb\u5316\u3002<\/p>\n

\u6211\u7684\u95ee\u9898\u662f\uff0c\u662f\u5426\u53ef\u4ee5\u4f7f\u7528 func main()<\/code> \u800c\u4e0d\u662f func init()<\/code> \u6765\u6267\u884c\u76f8\u540c\u7684\u64cd\u4f5c\u3002<\/p>\n

\u4f7f\u7528 func init()<\/code> \u57fa\u672c\u4e0a\u4f7f\u6211\u7684\u5904\u7406\u7a0b\u5e8f\u51fd\u6570 (func lambdahandler<\/code>) \u7531\u4e8e func init()<\/code> \u8fd0\u884c\u7684\u526f\u4f5c\u7528\u800c\u65e0\u6cd5\u8fdb\u884c\u5355\u5143\u6d4b\u8bd5\u3002<\/p>\n

\u5c06 func init()<\/code> \u4ee3\u7801\u79fb\u81f3 func main()<\/code> \u4f3c\u4e4e\u53ef\u4ee5\u8f7b\u677e\u89e3\u51b3\u6b64\u95ee\u9898\u3002<\/p>\n

\u4f7f\u7528 func main()<\/code> \u4e0e func init()<\/code> \u662f\u5426\u6709\u4efb\u4f55\u526f\u4f5c\u7528<\/p>\n

\u4ee3\u7801\u793a\u4f8b<\/p>\n

\u4f7f\u7528 func init()<\/strong><\/p>\n

package main\n \nimport (\n        \"log\"\n        \"github.com\/aws\/aws-lambda-go\/lambda\"\n        \"github.com\/aws\/aws-sdk-go\/aws\/session\"\n        \"github.com\/aws\/aws-sdk-go\/service\/s3\"\n        \"github.com\/aws\/aws-sdk-go\/aws\"\n)\n \nvar invokecount = 0\nvar myobjects []*s3.object\nfunc init() {\n        svc := s3.new(session.new())\n        input := &s3.listobjectsv2input{\n                bucket: aws.string(\"examplebucket\"),\n        }\n        result, _ := svc.listobjectsv2(input)\n        myobjects = result.contents\n}\n \nfunc lambdahandler() (int, error) {\n        invokecount = invokecount + 1\n        log.print(myobjects)\n        return invokecount, nil\n}\n \nfunc main() {\n        lambda.start(lambdahandler)\n}<\/pre>\n
\u5bf9\u6bd4<\/strong><\/p>\n
\u4f7f\u7528 func main()<\/strong><\/p>\n
package main\n \nimport (\n        \"log\"\n        \"github.com\/aws\/aws-lambda-go\/lambda\"\n        \"github.com\/aws\/aws-sdk-go\/aws\/session\"\n        \"github.com\/aws\/aws-sdk-go\/service\/s3\"\n        \"github.com\/aws\/aws-sdk-go\/aws\"\n)\n \nvar invokeCount = 0\nvar myObjects []*s3.Object\n \nfunc LambdaHandler() (int, error) {\n        invokeCount = invokeCount + 1\n        log.Print(myObjects)\n        return invokeCount, nil\n}\n \nfunc main() {\n        svc := s3.New(session.New())\n        input := &s3.ListObjectsV2Input{\n                Bucket: aws.String(\"examplebucket\"),\n        }\n        result, _ := svc.ListObjectsV2(input)\n        myObjects = result.Contents\n\n        lambda.Start(LambdaHandler)\n}<\/pre>\n
 <\/p>\n
\u6b63\u786e\u7b54\u6848<\/h2>\n
 <\/p>\n
\u6211\u4f1a\u63d0\u51fa\u4ee5\u4e0b\u5efa\u8bae\uff08\u6211\u4eec\u5728\u5f88\u591a go lambda \u4e2d\u90fd\u6210\u529f\u4f7f\u7528\u4e86\u5b83\uff09\u3002<\/p>\n
ma\u200b\u200bin.go<\/strong><\/p>\n
[...]\n\nfunc (h *handler) handlerequest(ctx context.context) error {\n    input := h.s3client.listobjectsv2input{\n        bucket: aws.string(\"examplebucket\"),\n    }\n\n    [...]\n}\n\ntype handler struct {\n    s3client s3iface.s3api\n}\n\n\/\/ main is called only once, when the lambda is initialised (started for the first time). code in this function should\n\/\/ primarily be used to create service clients, read environments variables, read configuration from disk etc.\nfunc main() {\n    h := handler{\n        s3client: s3.new(session.new()),\n    }\n\n    lambda.start(h.handlerequest)\n}\n<\/pre>\n
ma\u200b\u200bin_test.go<\/strong><\/p>\n
type ListObjectsV2Mock struct {\n    s3iface.S3API\n\n    output *s3.ListObjectsV2Output\n}\n\nfunc TestHandleRequest(t *testing.T) {\n    h := handler{\n        s3Client: &ListObjectsV2Mock{\n            output: &s3.ListObjectsV2Output{...},\n        },\n    }\n\n    err := h.HandleRequest(context.TODO())\n    if err != nil {\n        t.Fatalf(\"unexpected error: %v\", err)\n    }\n}\n<\/pre>\n
\u663e\u7136\uff0c\u7f3a\u5c11\u5f88\u591a\u4ee3\u7801\uff08\u5bfc\u5165\u3001\u9519\u8bef\u5904\u7406\u7b49\uff09\uff0c\u4f46\u8fd9\u5c31\u662f\u8981\u70b9\u3002<\/p>\n
\u7406\u8bba\u8981\u638c\u63e1\uff0c\u5b9e\u64cd\u4e0d\u80fd\u843d\uff01\u4ee5\u4e0a\u5173\u4e8e\u300afunc init() \u4e0e func main() \u7528\u4e8e\u521d\u59cb\u5316 AWS Lambda \u5904\u7406\u7a0b\u5e8f\u4e2d\u7684\u5168\u5c40\u72b6\u6001\u300b\u7684\u8be6\u7ec6\u4ecb\u7ecd\uff0c\u5927\u5bb6\u90fd\u638c\u63e1\u4e86\u5427\uff01\u5982\u679c\u60f3\u8981\u7ee7\u7eed\u63d0\u5347\u81ea\u5df1\u7684\u80fd\u529b\uff0c\u90a3\u4e48\u5c31\u6765\u5173\u6ce8\u516c\u4f17\u53f7\u5427\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-207020","post","type-post","status-publish","format-standard","hentry","category-4925"],"_links":{"self":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/207020","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=207020"}],"version-history":[{"count":0,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/207020\/revisions"}],"wp:attachment":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/media?parent=207020"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/categories?post=207020"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/tags?post=207020"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}