有什么原因导致curl命令不能使用变量吗？
这是我的设置 - 我没有使用实际值，因为我无法公开客户端数据并且没有测试环境。
您会注意到我正在使用两个curl命令，是的，我知道它可以组合成一个命令，但我无法使这一工作起作用，所以我将其分成两个单独的命令进行测试。
在这里，我设置了系统上入站文件夹的路径：
[root@acme logs]# act="roadrunner"
[root@acme logs]# content="xml"
[root@acme logs]# inbndfldr='/ftp/'"$act"'/inbound'
[root@acme logs]# destinationFolder="$inbndfldr"/"$content"/
[root@acme logs]# logFolder="$inbndfldr"/logs
在这里，我设置了远程系统上出站文件夹的路径：
[root@acme logs]# targetHost="SFTP://welcometotheroad.net"
[root@acme logs]# THFolderName="OUTBOUND"
[root@acme logs]# THFolder='/'"$THFolderName"
[root@acme logs]# THSftpAddress=$targetHost$THFolder
[root@acme logs]# THDeleteSftpAddress=$targetHost$THFolder'/'
这里我在远程系统上设置身份验证：
[root@acme logs]# username=mrRoadRunner
[root@acme logs]# password=Beep-8eep!
[root@acme logs]# sessionAuthentication="$username":"$password"
这里我设置了文件引用：
[root@acme logs]# fileref="openroad2019.xml"
这里我验证该文件是否存在于远程服务器上：
[root@acme logs]# THFiles=$(curl -sSk -u $sessionAuthentication $THSftpAddress | grep $fileref | awk '{print $9}')
[root@acme logs]# echo $THFiles
[root@acme logs]# openroad2019.xml
我在这里开始我的循环：
[root@acme logs]# for targetFile in $THFiles
> do
> dateTimeStamp=`date +%Y%m%d%H%M%S`
> traceLog="$logFolder"/"$targetFile"trace"$dateTimeStamp".log
> testLog="$logFolder"/test"$dateTimeStamp".log
> deltraceLog="$logFolder"/del"$targetFile"trace"$dateTimeStamp".log
> deltestLog="$logFolder"/deltest"$dateTimeStamp".log
> deleteString='"-rm '"$THFolderName"'/'"$targetFile"'"'
> masterGetStr=`echo curl \-k \-\-trace "$traceLog" \-\-user "$sessionAuthentication" \-O "$THSftpAddress"\/"$targetFile" \-\-ftp\-ssl \&\>\>"$testLog" 2\>\&1`
> masterDeleteStr=`echo curl \-sSk \-\-trace $deltraceLog \-u $sessionAuthentication $THDeleteSftpAddress \-Q$deleteString \&\>\> $deltestLog 2\>\&1`
> echo
> echo \-\-\-\-\-
> echo "$masterGetStr"
> echo \-\-
> echo "$masterDeleteStr"
> echo \-\-\-\-\-
> echo
> curl -k --trace "$traceLog" --user "$sessionAuthentication" -O "$THSftpAddress"/"$targetFile" --ftp-ssl &>> "$testLog" 2>&1
> curl -sSk --trace $deltraceLog -u $sessionAuthentication $THDeleteSftpAddress -Q$deleteString &>> $deltestLog 2>&1
> done
这是输出：
-----
curl -k --trace /ftp/roadrunner/inbound/logs/openroad2019.xmltrace20190628180349.log --user mrRoadRunner:Beep-8eep! -O SFTP://welcometotheroad.net/OUTBOUND/openroad2019.xml --ftp-ssl &>>/ftp/roadrunner/inbound/logs/test20190628180349.log 2>&1
--
curl -sSk --trace /ftp/roadrunner/inbound/logs/delopenroad2019.xmltrace20190628180349.log -u mrRoadRunner:Beep-8eep! SFTP://welcometotheroad.net/OUTBOUND/ -Q"-rm OUTBOUND/openroad2019.xml" &>> /ftp/roadrunner/inbound/logs/deltest20190628180349.log 2>&1
-----
第一个curl命令工作得很好，将文件放在我需要的地方。
第二个curl命令应该删除远程系统上的文件，但它不起作用。我在这里查看相关日志：
::::::::::::::
delopenroad2019.xmltrace20190628180349.log
::::::::::::::
== Info: Trying 0.0.0.0...
== Info: TCP_NODELAY set
== Info: Connected to welcometotheroad.net (0.0.0.0) port 22 (#0)
== Info: SSH MD5 fingerprint: Th3re1$4WarpDr1v3N$+4r$#1P!
== Info: SSH authentication methods available: publickey,password
== Info: Using SSH private key file '/root/.ssh/id_rsa'
== Info: SSH public key authentication failed: Username/PublicKey combination invalid
== Info: Initialized password authentication
== Info: Authentication complete
== Info: Sending quote commands
== Info: Syntax error in SFTP command. Supply parameter(s)!
== Info: Connection #0 to host welcometotheroad.net left intact
== Info: getaddrinfo(3) failed for OUTBOUND:80
== Info: Couldn't resolve host 'OUTBOUND'
== Info: Closing connection 1
::::::::::::::
deltest20190628180349.log
::::::::::::::
curl: (21) Syntax error in SFTP command. Supply parameter(s)!
curl: (6) Couldn't resolve host 'OUTBOUND'
::::::::::::::
test20190628180349.log
::::::::::::::
% Total % Received % Xferd Average Speed Time Time Time Current
Dload Upload Total Spent Left Speed
100 4290 100 4290 0 0 3248 0 0:00:01 0:00:01 --:--:-- 3252
100 4290 100 4290 0 0 3247 0 0:00:01 0:00:01 --:--:-- 3247
[root@acme logs]#
然而，当我手动输入命令时 - 它会起作用并从远程系统中删除该文件。
curl -sSk --trace /ftp/roadrunner/inbound/logs/delopenroad2019.xmltrace20190628180349.log -u mrRoadRunner:Beep-8eep! SFTP://welcometotheroad.net/OUTBOUND/ -Q"-rm OUTBOUND/openroad2019.xml" &>> /ftp/roadrunner/inbound/logs/deltest20190628180349.log 2>&1
[root@rh1 logs]# more *20190628180546*.log
::::::::::::::
openroad2019.xmltrace20190628180546.log
::::::::::::::
Info: Trying 0.0.0.0...
== Info: TCP_NODELAY set
== Info: Connected to welcometotheroad.net (0.0.0.0) port 22 (#0)
== Info: SSH MD5 fingerprint: Th3re1$4WarpDr1v3N$+4r$#1P!
== Info: SSH authentication methods available: publickey,password
== Info: Using SSH private key file '/root/.ssh/id_rsa'
== Info: SSH public key authentication failed: Username/PublicKey combination invalid
== Info: Initialized password authentication
== Info: Authentication complete
<= Recv data, 2000 bytes (0x7d0)
0000: ef bb bf 3c 3f 78 6d 6c 20 76 65 72 73 69 6f 6e ...<?xml version
...
... (details removed)
...
0110: 6e 73 74 72 75 63 74 69 6f 6e 73 48 65 61 64 65 nstructionsHeade
0120: 72 3e r>
== Info: Connection #0 to host welcometotheroad.net left intact
::::::::::::::
del_openroad2019.xmltrace20190628180546.log
::::::::::::::
== Info: Trying 0.0.0.0...
== Info: TCP_NODELAY set
== Info: Connected to welcometotheroad.net (0.0.0.0) port 22 (#0)
== Info: SSH MD5 fingerprint: Th3re1$4WarpDr1v3N$+4r$#1P!
== Info: SSH authentication methods available: publickey,password
== Info: Using SSH private key file '/root/.ssh/id_rsa'
== Info: SSH public key authentication failed: Username/PublicKey combination invalid
== Info: Initialized password authentication
== Info: Authentication complete
=> Send data, 55 bytes (0x37)
0000: 64 72 77 78 72 2d 78 2d 2d 2d 20 32 20 66 74 70 drwxr-x--- 2 ftp
0010: 61 64 6d 69 6e 20 66 74 70 61 64 6d 69 6e 20 20 admin ftpadmin
...
... (details removed)
...
0050: 30 30 2d 32 36 37 36 39 36 37 33 5f 44 49 5f 4c 00-26769673_DI_L
0060: 45 30 2e 58 4d 4c 0a E0.XML.
== Info: Sending quote commands
== Info: Connection #0 to host welcometotheroad.net left intact
::::::::::::::
delopenroad2019.xmltrace20190628180546.log
::::::::::::::
== Info: Trying 0.0.0.0...
== Info: TCP_NODELAY set
== Info: Connected to welcometotheroad.net (0.0.0.0) port 22 (#0)
== Info: SSH MD5 fingerprint: Th3re1$4WarpDr1v3N$+4r$#1P!
== Info: SSH authentication methods available: publickey,password
== Info: Using SSH private key file '/root/.ssh/id_rsa'
== Info: SSH public key authentication failed: Username/PublicKey combination invalid
== Info: Initialized password authentication
== Info: Authentication complete
== Info: Sending quote commands
== Info: Syntax error in SFTP command. Supply parameter(s)!
== Info: Connection #0 to host welcometotheroad.net left intact
== Info: getaddrinfo(3) failed for OUTBOUND:80
== Info: Couldn't resolve host 'OUTBOUND'
== Info: Closing connection 1
::::::::::::::
del_test20190628180546.log
::::::::::::::
drwxr-x--- 2 ftpadmin ftpadmin 0 Jun 28 23:38 .
drwxr-x--- 2 ftpadmin ftpadmin 0 Apr 26 2019 ..
-rwxr-x--- 1 ftpadmin ftpadmin 7780 Jun 27 14:36 NextFile20190620172738.XML
-rwxr-x--- 1 ftpadmin ftpadmin 2440 Jun 27 14:36 NextFile20190620172740.XML
-rwxr-x--- 1 ftpadmin ftpadmin 7980 Jun 27 14:36 NextFile20190624111531.XML
-rwxr-x--- 1 ftpadmin ftpadmin 2441 Jun 27 14:36 NextFile20190624111533.XML
-rwxr-x--- 1 ftpadmin ftpadmin 7858 Jun 27 14:36 NextFile20190626165728.XML
-rwxr-x--- 1 ftpadmin ftpadmin 2500 Jun 27 14:36 NextFile20190626165729.XML
-rwxr-x--- 1 ftpadmin ftpadmin 15424 Jun 27 14:36 NextFile20190627091426.XML
-rwxr-x--- 1 ftpadmin ftpadmin 4104 Jun 27 14:37 NextFile20190627091427.XML
-rwxr-x--- 1 ftpadmin ftpadmin 10417 Jun 27 14:37 NextFile20190627092525.XML
-rwxr-x--- 1 ftpadmin ftpadmin 3071 Jun 27 14:37 NextFile20190627092527.XML
-rwxr-x--- 1 ftpadmin ftpadmin 15594 Jun 27 14:37 NextFile20190627093345.XML
-rwxr-x--- 1 ftpadmin ftpadmin 4279 Jun 27 14:37 NextFile20190627093347.XML
-rwxr-x--- 1 ftpadmin ftpadmin 17237 Jun 27 14:37 NextFile20190627094528.XML
-rwxr-x--- 1 ftpadmin ftpadmin 4290 Jun 27 14:37 NextFile20190627094530.XML
-rwxr-x--- 1 ftpadmin ftpadmin 15608 Jun 27 14:37 NextFile20190627100222.XML
-rwxr-x--- 1 ftpadmin ftpadmin 4288 Jun 27 14:37 NextFile20190627100224.XML
-rwxr-x--- 1 ftpadmin ftpadmin 2455 Jun 27 14:37 NextFile20190627102026.XML
-rwxr-x--- 1 ftpadmin ftpadmin 7858 Jun 27 15:18 NextFile20190627111647.XML
-rwxr-x--- 1 ftpadmin ftpadmin 2500 Jun 27 15:18 NextFile20190627111648.XML
-rwxr-x--- 1 ftpadmin ftpadmin 7858 Jun 27 18:56 NextFile20190627145327.XML
-rwxr-x--- 1 ftpadmin ftpadmin 2500 Jun 27 18:56 NextFile20190627145328.XML
-rwxr-x--- 1 ftpadmin ftpadmin 12797 Jun 27 20:08 NextFile20190627160344.XML
-rwxr-x--- 1 ftpadmin ftpadmin 3609 Jun 27 20:08 NextFile20190627160345.XML
我的问题是“为什么它不能在循环中工作？”
答案1
不要（尝试）在变量中添加引号。
Shell 命令解析以明确的、固定的顺序进行，并且变量替换（正式的参数扩展）完成（好吧！）后处理命令行引用。当你这样做时
deleteString='"-rm '"$THFolderName"'/'"$targetFile"'"'
...
curl ... -Q$deleteString ...
它将值放入"-rm OUTBOUND/openroad2019.xml"变量中，当该值被替换时，它会在空格（或一般的 IFS）处分割并传递二卷曲的参数（除了其他参数）如下：
...
-Q"-rm
OUTBOUND/openroad2019.xml"
...
其中第一个会使远程服务器感到困惑并产生错误
Syntax error in SFTP command. Supply parameter(s)!
第二个被curl视为第二个要访问的URL，导致它正确地抱怨 OUTBOUND 不是有效的主机名。
相反，将空格引用到变量值中，然后用双引号引起来代换保留该空间，但不要添加任何类型的引号在价值：
deleteString="-rm $THFolderName/$targetfile"
...
curl ... -Q"$deleteString" ...
# or if you prefer
curl ... "-Q$deleteString" ...
# (-Q are not special to shell so it doesn't matter if they're quoted)
# or more simply drop the extra variable and just
curl ... -Q"-rm $THFolderName/$targetfile" ...
和它与 for 循环没有任何关系仅与变量有关。
仅供参考，您的复杂而笨重的echo命令显然试图“重建”shell 的功能，但实际上并没有这样做，并且可能通过误导您来浪费您的时间。如果您想知道 shell 如何扩展并执行命令，请设置选项x和它会告诉你。对于特定命令（或此处两个），请执行set -x之前和set +x之后的操作。对于脚本，您只需运行即可调试整个脚本，sh -x script args...无需编辑。