Powershell FTP script -

i'm using script in loop download number of files server , works pretty good.

$sourceuri = "ftp://ftp.secureftp-test.com/hamlet.zip" $targetpath = "c:\hamlet.zip" $username = "test" $password = "test"  # create ftpwebrequest object handle connection ftp server $ftprequest = [system.net.ftpwebrequest]::create($sourceuri)  # set request's network credentials authenticated connection $ftprequest.credentials = new-object system.net.networkcredential($username,$password)  $ftprequest.method = [system.net.webrequestmethods+ftp]::downloadfile $ftprequest.usebinary = $true $ftprequest.keepalive = $false  # send ftp request server $ftpresponse = $ftprequest.getresponse()  # download stream server response $responsestream = $ftpresponse.getresponsestream()  # create target file on local system , download buffer $targetfile = new-object io.filestream ($targetpath,[io.filemode]::create) [byte[]]$readbuffer = new-object byte[] 1024  # loop through download stream , send data target file do{     $readlength = $responsestream.read($readbuffer,0,1024)     $targetfile.write($readbuffer,0,$readlength) } while ($readlength -ne 0)  $targetfile.close() 

but target file not there , script starts flushing command prompt errors. kinda anoying debug, of files missing. there way, turn of script there missing file , skip to next one?

here error:

exception calling "getresponse" "0" argument(s): "the remote server returned n error: (550) file unavailable (e.g., file not found, no access)." @ d:\powershell\ipo_preveri_cmd_all\ftp.ps1:37 char:5 +     $ftpresponse = $ftprequest.getresponse() +     ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~     + categoryinfo          : notspecified: (:) [], methodinvocationexception     + fullyqualifiederrorid : webexception  cannot call method on null-valued expression. @ d:\powershell\ipo_preveri_cmd_all\ftp.ps1:40 char:5 +     $responsestream = $ftpresponse.getresponsestream() +     ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~     + categoryinfo          : invalidoperation: (:) [], runtimeexception     + fullyqualifiederrorid : invokemethodonnull 

the last 6 lines repeated...

sounds asking simple try-catch. don't know of error handling [system.net.ftpwebrequest] has offer generic approach place start.

$savederroractionpreference = $erroractionpreference $erroractionpreference = "stop"   try{     # send ftp request server     $ftpresponse = $ftprequest.getresponse()      # download stream server response     $responsestream = $ftpresponse.getresponsestream()      # create target file on local system , download buffer     $targetfile = new-object io.filestream ($targetpath,[io.filemode]::create)     [byte[]]$readbuffer = new-object byte[] 1024      # loop through download stream , send data target file     do{         $readlength = $responsestream.read($readbuffer,0,1024)         $targetfile.write($readbuffer,0,$readlength)     }     while ($readlength -ne 0)      $targetfile.close() } catch {     # notify user error occured.      write-warning "unable download '$sourceuri' because: $($_.exception)" }  $erroractionpreference = $savederroractionpreference  

so if any terminating error occurs in try block processing stopped , catch block executed. looks of errors not terminating need to temporarily change stop ensure try block functions properly.

then in catch block take simplest approach , write out file path failed while providing message associated error. using above example should like:

unable download 'ftp://ftp.secureftp-test.com/hamlet.zip' because: remote server returned error: (550) file unavailable (e.g., file not found, no access).

this should stop on first error. ceasing processing avoid null expression errors.