使用go http client Do方法時，httpResponse和error可以不同時爲零嗎？

在official documentation作爲可見以及幾乎其他地方上網，處理HTTP客戶端錯誤的常見模式是：使用go http client Do方法時，httpResponse和error可以不同時爲零嗎？

req, err := http.NewRequest("GET", "http://example.com", nil) 
req.Header.Add("If-None-Match", `W/"wyzzy"`) 
resp, err := client.Do(req) 
if err != nil { 
    // handle error 
} 
defer resp.Body.Close()

閱讀有關HTTP客戶端的方法的文檔，我無法理解是否可以同時接收resp和err不爲零，好像這是可能的，如果我們考慮的是怎樣寫的溶解氧方法文檔中：

The request Body, if non-nil, will be closed by the underlying Transport, even on errors.

On error, any Response can be ignored. A non-nil Response with a non-nil error only occurs when CheckRedirect fails, and even then the returned Response.Body is already closed.

所以我的問題有以下幾點：

是否有可能在同一時間接收非空resp和err？
如果它是可能的，並且在我的程序我最終接收了很多錯誤，我在//handle error片的代碼return或panic如上所示，從而之後從未到達延遲，是有可能，在長遠來說，我最終會得到太多開放的機構，交通工具無法關閉？

語境附錄：

我遇到的問題是，經過一段時間，程序與標準錯誤夠程以下大印刷崩潰，並按照跟蹤我最後一塊的代碼，這似乎是正常的，除非遇到錯誤，如果遇到錯誤，並有一個響應身體沒有延遲關閉將作出，但由於官方文檔說不擔心它，問題必須在其他地方...

Stderr logs 
    Display timestamps 
net/http.(*persistConn).readLoop(0xc4244e0240) 
    /usr/local/go/src/net/http/transport.go:1474 +0x196 
created by net/http.(*Transport).dialConn 
    /usr/local/go/src/net/http/transport.go:1117 +0xa35 

goroutine 194055 [select, 2 minutes]: 
net/http.(*persistConn).readLoop(0xc42421ec60) 
    /usr/local/go/src/net/http/transport.go:1599 +0x9ec 
created by net/http.(*Transport).dialConn 
    /usr/local/go/src/net/http/transport.go:1117 +0xa35 

goroutine 215944 [IO wait]: 
net.runtime_pollWait(0x7f63736f0628, 0x72, 0x21b) 
    /usr/local/go/src/runtime/netpoll.go:164 +0x59 
net.(*pollDesc).wait(0xc420963568, 0x72, 0xa85c40, 0xa81350) 
    /usr/local/go/src/net/fd_poll_runtime.go:75 +0x38 
net.(*pollDesc).waitRead(0xc420963568, 0xc422289000, 0x1000) 
    /usr/local/go/src/net/fd_poll_runtime.go:80 +0x34 
net.(*netFD).Read(0xc420963500, 0xc422289000, 0x1000, 0x1000, 0x0, 0xa85c40, 0xa81350) 
    /usr/local/go/src/net/fd_unix.go:250 +0x1b7 
net.(*conn).Read(0xc42025bbb8, 0xc422289000, 0x1000, 0x1000, 0x0, 0x0, 0x0) 
    /usr/local/go/src/net/net.go:181 +0x70 
net/http.(*persistConn).Read(0xc4217af8c0, 0xc422289000, 0x1000, 0x1000, 0xc420b33400, 0x8b61a3, 0xc423dd6b80) 
    /usr/local/go/src/net/http/transport.go:1316 +0x14b 
bufio.(*Reader).fill(0xc421af0060) 
    /usr/local/go/src/bufio/bufio.go:97 +0x117 
bufio.(*Reader).Peek(0xc421af0060, 0x1, 0xc421af01e0, 0xc420536c80, 0xc420b17e00, 0x60, 0xc420536c60) 
    /usr/local/go/src/bufio/bufio.go:129 +0x67 
net/http.(*persistConn).readLoop(0xc4217af8c0) 
    /usr/local/go/src/net/http/transport.go:1474 +0x196 
created by net/http.(*Transport).dialConn 
    /usr/local/go/src/net/http/transport.go:1117 +0xa35 

goroutine 199855 [select, 1 minutes]: 
net/http.(*persistConn).writeLoop(0xc421db1320) 
    /usr/local/go/src/net/http/transport.go:1704 +0x43a 
created by net/http.(*Transport).dialConn 
    /usr/local/go/src/net/http/transport.go:1118 +0xa5a 

goroutine 198707 [select, 1 minutes]: 
net/http.(*persistConn).readLoop(0xc4236ea000) 
    /usr/local/go/src/net/http/transport.go:1599 +0x9ec 
created by net/http.(*Transport).dialConn 
    /usr/local/go/src/net/http/transport.go:1117 +0xa35 

goroutine 192577 [select, 2 minutes]: 
net/http.(*persistConn).readLoop(0xc424a8fc20) 
    /usr/local/go/src/net/http/transport.go:1599 +0x9ec 
created by net/http.(*Transport).dialConn 
    /usr/local/go/src/net/http/transport.go:1117 +0xa35 

goroutine 213681 [select]: 
net/http.(*persistConn).writeLoop(0xc42455e6c0) 
    /usr/local/go/src/net/http/transport.go:1704 +0x43a 
created by net/http.(*Transport).dialConn 
    /usr/local/go/src/net/http/transport.go:1118 +0xa5a 

goroutine 190222 [select, 2 minutes]: 
net/http.(*persistConn).writeLoop(0xc4238617a0) 
    /usr/local/go/src/net/http/transport.go:1704 +0x43a 
created by net/http.(*Transport).dialConn 
    /usr/local/go/src/net/http/transport.go:1118 +0xa5a 

goroutine 208970 [select, 1 minutes]: 
net/http.(*persistConn).writeLoop(0xc4234530e0) 
    /usr/local/go/src/net/http/transport.go:1704 +0x43a 
created by net/http.(*Transport).dialConn 
    /usr/local/go/src/net/http/transport.go:1118 +0xa5a 

goroutine 219699 [select]: 
net/http.(*persistConn).writeLoop(0xc42155cb40) 
    /usr/local/go/src/net/http/transport.go:1704 +0x43a 
created by net/http.(*Transport).dialConn 
    /usr/local/go/src/net/http/transport.go:1118 +0xa5a 

goroutine 221664 [select]: 
net/http.setRequestCancel.func3(0x0, 0xc4231af680, 0xc423657000, 0xc4214aeecc, 0xc422f926c0) 
    /usr/local/go/src/net/http/client.go:320 +0x17c 
created by net/http.setRequestCancel 
    /usr/local/go/src/net/http/client.go:330 +0x287 

goroutine 220550 [select]: 
net/http.(*persistConn).readLoop(0xc4218f0c60) 
    /usr/local/go/src/net/http/transport.go:1599 +0x9ec 
created by net/http.(*Transport).dialConn 
    /usr/local/go/src/net/http/transport.go:1117 +0xa35 

goroutine 216169 [IO wait]: 
net.runtime_pollWait(0x7f6373700fb0, 0x72, 0x221) 
    /usr/local/go/src/runtime/netpoll.go:164 +0x59 
net.(*pollDesc).wait(0xc4212fdb18, 0x72, 0xa85c40, 0xa81350) 
    /usr/local/go/src/net/fd_poll_runtime.go:75 +0x38 
net.(*pollDesc).waitRead(0xc4212fdb18, 0xc42393c000, 0x1000) 
    /usr/local/go/src/net/fd_poll_runtime.go:80 +0x34 
net.(*netFD).Read(0xc4212fdab0, 0xc42393c000, 0x1000, 0x1000, 0x0, 0xa85c40, 0xa81350) 
    /usr/local/go/src/net/fd_unix.go:250 +0x1b7 
net.(*conn).Read(0xc42300aa38, 0xc42393c000, 0x1000, 0x1000, 0x0, 0x0, 0x0) 
    /usr/local/go/src/net/net.go:181 +0x70 
net/http.(*persistConn).Read(0xc422102c60, 0xc42393c000, 0x1000, 0x1000, 0xc423d30820, 0xc42002a800, 0xc424422b80) 
    /usr/local/go/src/net/http/transport.go:1316 +0x14b 
bufio.(*Reader).fill(0xc4220598c0) 
    /usr/local/go/src/bufio/bufio.go:97 +0x117 
bufio.(*Reader).Peek(0xc4220598c0, 0x1, 0xc422059a40, 0xc420535c80, 0xc422059700, 0x60, 0xc420535c60) 
    /usr/local/go/src/bufio/bufio.go:129 +0x67 
net/http.(*persistConn).readLoop(0xc422102c60) 
    /usr/local/go/src/net/http/transport.go:1474 +0x196 
created by net/http.(*Transport).dialConn 
    /usr/local/go/src/net/http/transport.go:1117 +0xa35 

goroutine 213706 [select]: 
net/http.(*persistConn).writeLoop(0xc42321d200) 
    /usr/local/go/src/net/http/transport.go:1704 +0x43a 
created by net/http.(*Transport).dialConn 
    /usr/local/go/src/net/http/transport.go:1118 +0xa5a 

goroutine 214335 [select]: 
net/http.(*persistConn).writeLoop(0xc4230d7560) 
    /usr/local/go/src/net/http/transport.go:1704 +0x43a 
created by net/http.(*Transport).dialConn 
    /usr/local/go/src/net/http/transport.go:1118 +0xa5a 

goroutine 221651 [IO wait]: 
net.runtime_pollWait(0x7f63736eff38, 0x72, 0x254) 
    /usr/local/go/src/runtime/netpoll.go:164 +0x59 
net.(*pollDesc).wait(0xc422449b18, 0x72, 0xa85c40, 0xa81350) 
    /usr/local/go/src/net/fd_poll_runtime.go:75 +0x38 
net.(*pollDesc).waitRead(0xc422449b18, 0xc423d93000, 0x1000) 
    /usr/local/go/src/net/fd_poll_runtime.go:80 +0x34 
net.(*netFD).Read(0xc422449ab0, 0xc423d93000, 0x1000, 0x1000, 0x0, 0xa85c40, 0xa81350) 
    /usr/local/go/src/net/fd_unix.go:250 +0x1b7 
net.(*conn).Read(0xc421eb21b8, 0xc423d93000, 0x1000, 0x1000, 0x0, 0x0, 0x0) 
    /usr/local/go/src/net/net.go:181 +0x70 
net/http.(*persistConn).Read(0xc422e5b440, 0xc423d93000, 0x1000, 0x1000, 0x8cc888, 0x0, 0xc42347bb80) 
    /usr/local/go/src/net/http/transport.go:1316 +0x14b 
bufio.(*Reader).fill(0xc422f2c960) 
    /usr/local/go/src/bufio/bufio.go:97 +0x117 
bufio.(*Reader).Peek(0xc422f2c960, 0x1, 0xc422f2d6e0, 0xc420b8ec80, 0xc42180ff00, 0x60, 0xc420b8ec60) 
    /usr/local/go/src/bufio/bufio.go:129 +0x67 
net/http.(*persistConn).readLoop(0xc422e5b440) 
    /usr/local/go/src/net/http/transport.go:1474 +0x196 
created by net/http.(*Transport).dialConn 
    /usr/local/go/src/net/http/transport.go:1117 +0xa35 

goroutine 221670 [IO wait]: 
net.runtime_pollWait(0x7f63736ff7b0, 0x72, 0x259) 
    /usr/local/go/src/runtime/netpoll.go:164 +0x59 
net.(*pollDesc).wait(0xc422449b88, 0x72, 0xa85c40, 0xa81350) 
    /usr/local/go/src/net/fd_poll_runtime.go:75 +0x38 
net.(*pollDesc).waitRead(0xc422449b88, 0xc423f28000, 0x1000) 
    /usr/local/go/src/net/fd_poll_runtime.go:80 +0x34 
net.(*netFD).Read(0xc422449b20, 0xc423f28000, 0x1000, 0x1000, 0x0, 0xa85c40, 0xa81350) 
    /usr/local/go/src/net/fd_unix.go:250 +0x1b7 
net.(*conn).Read(0xc423eac3c8, 0xc423f28000, 0x1000, 0x1000, 0x0, 0x0, 0x0) 
    /usr/local/go/src/net/net.go:181 +0x70 
net/http.(*persistConn).Read(0xc4235930e0, 0xc423f28000, 0x1000, 0x1000, 0xa82dc0, 0xc42000e0b0, 0xc423be7b80) 
    /usr/local/go/src/net/http/transport.go:1316 +0x14b 
bufio.(*Reader).fill(0xc422bb70e0) 
    /usr/local/go/src/bufio/bufio.go:97 +0x117 
bufio.(*Reader).Peek(0xc422bb70e0, 0x1, 0xc422bb7320, 0xc424191480, 0xc4237a4820, 0x0, 0xc422ac9138) 
    /usr/local/go/src/bufio/bufio.go:129 +0x67 
net/http.(*persistConn).readLoop(0xc4235930e0) 
    /usr/local/go/src/net/http/transport.go:1474 +0x196 
created by net/http.(*Transport).dialConn 
    /usr/local/go/src/net/http/transport.go:1117 +0xa35 

goroutine 213543 [select]: 
net/http.(*persistConn).readLoop(0xc424795c20) 
    /usr/local/go/src/net/http/transport.go:1599 +0x9ec 
created by net/http.(*Transport).dialConn 
    /usr/local/go/src/net/http/transport.go:1117 +0xa35 

goroutine 220529 [select]: 
net/http.(*persistConn).roundTrip(0xc4215fd680, 0xc4212c5c80, 0x0, 0x0, 0x0) 
    /usr/local/go/src/net/http/transport.go:1898 +0x974 
net/http.(*Transport).RoundTrip(0xc420847b30, 0xc421248800, 0xc420847b30, 0xed15b2cf4, 0x16cd81f7) 
    /usr/local/go/src/net/http/transport.go:391 +0x74c 
net/http.send(0xc421248700, 0xa84080, 0xc420847b30, 0xed15b2cf4, 0x16cd81f7, 0xab7060, 0x0, 0x8, 0xc4213a2a80, 0x40f258) 
    /usr/local/go/src/net/http/client.go:249 +0x162 
net/http.(*Client).send(0xc42075ed20, 0xc421248700, 0xed15b2cf4, 0x16cd81f7, 0xab7060, 0xc4213a2a80, 0x0, 0x1, 0x4084fe) 
    /usr/local/go/src/net/http/client.go:173 +0x108 
net/http.(*Client).Do(0xc42075ed20, 0xc421248700, 0xa, 0x8b359b, 0x5) 
    /usr/local/go/src/net/http/client.go:595 +0x254 
github.com/myCompanyName/gojsonrpc.(*Client).sendJsonRequest(0xc42078c6e0, 0xc4215fd320, 0xbb, 0x11a, 0x0, 0x0, 0x0, 0x0, 0x0) 
    /home/ubuntu/go/src/github.com/myCompanyName/gojsonrpc/client.go:45 +0x2f2 
github.com/myCompanyName/gojsonrpc.(*Client).Run(0xc42078c6e0, 0x8be6b2, 0x1d, 0x838780, 0xc420789ce0, 0x7fb2e0, 0xc4212c5b40, 0x1, 0xe) 
    /home/ubuntu/go/src/github.com/myCompanyName/gojsonrpc/client.go:72 +0x219 
github.com/myCompanyName/app/connectors/vendor.(*Connector).ReadStatus(0xc42078aa30, 0xc4212c5a60, 0xd, 0xc4212c5a6e, 0x7, 0xc4212c59c0, 0x1d, 0x0, 0x0, 0x0, ...) 
    /home/ubuntu/go/src/github.com/myCompanyName/app/connectors/vendor/tickets.go:52 +0x386 
github.com/myCompanyName/app/obscuredPkgName/connabslayer.(*ConnAbsLayer).ReadMetrics(0xc42075ac40, 0xc4212c5a60, 0x15, 0xc4212c59c0, 0x1d, 0xc42121eb30, 0xf) 
    /home/ubuntu/go/src/github.com/myCompanyName/app/obscuredPkgName/connabslayer/connector_abstraction_layer.go:145 +0xdc 
github.com/myCompanyName/app/obscuredPkgName/updater/plugins.(*UpdaterPlugin).SyncPluggedData(0xc42078c820, 0xc4208b9ef0, 0x28, 0xf) 
    /home/ubuntu/go/src/github.com/myCompanyName/app/obscuredPkgName/updater/plugins/vendor_plugin.go:69 +0x1e1 
github.com/myCompanyName/app/obscuredPkgName/updater.(*Updater).syncData.func1(0xc420763a00, 0xc4208b9ef0, 0x28, 0xc4201824f0, 0xf) 
    /home/ubuntu/go/src/github.com/myCompanyName/app/obscuredPkgName/updater/updater.go:127 +0xf6 
created by github.com/myCompanyName/app/obscuredPkgName/updater.(*Updater).syncData 
    /home/ubuntu/go/src/github.com/myCompanyName/app/obscuredPkgName/updater/updater.go:131 +0x17b 

// AND SO ON

解決方案：

問題出在其他地方，在下面的評論中可以看到，但這個問題可能對其他人詢問相同的問題很有用。

來源

2017-09-26 dev_mush

相關/可能的重複[如果調用http.Get（url）時發生錯誤，我們是否需要關閉響應對象？]（https://stackoverflow.com/questions/32818472/do-we-need-to- close-the-response-object-if-an-error-calling-while-calling-http-ge/32819910＃32819910） – icza

1.是的，正如文檔所述。但是，如果錯誤！=零，你可以忽略身體。 2.否，請參閱您引用的文檔。 – Volker

這只是堆棧跟蹤的一部分，你實際得到了什麼錯誤？你使用什麼版本的Go？堆棧跟蹤看起來不像最近發佈的版本。 – JimB

是的，在一種情況下，它們都可以是非零，顯然。從the source，我們看到：

 if err != nil { 
      // Special case for Go 1 compatibility: return both the response 
      // and an error if the CheckRedirect function failed. 
      // See https://golang.org/issue/3795 
      // The resp.Body has already been closed. 
      ue := uerr(err) 
      ue.(*url.Error).URL = loc 
      return resp, ue 
     }

每隔回報或者返回的響應和零犯錯，或無響應和非零誤差。
因此，對於上述問題：

是
不能發生的，其中兩個主體和錯誤是不爲零的唯一情況，身體已經關閉

來源

2017-09-26 10:59:46 Flimzy

因此，在這種情況下，無論如何，身體被關閉，這意味着我的問題不能與未被延期關閉的身體相關... –

使用go http client Do方法時，httpResponse和error可以不同時爲零嗎？

回答

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