Executing command doesn't result in script exception - powershell

Question

We have a powershell script that deploys a database script. However, if the database script fails, the output doesn't throw exceptions to the powershell script.
Below is an example of the .ps1 file:
function Publish-DatabaseProject
{
sqlcmd -S . -b -v DatabaseName=Integration -q "alter table xx add test Varchar(10)"
}
function Add-Timestamp {
process {
if ($_.GetType() -eq [string]) {
"[$(Get-Date -Format o)] $_"
} else {
$_
}
}
}
function Write-LogFile {
[CmdletBinding()]
param(
[Parameter(Mandatory=$true)] [string] $Path,
[Parameter(Mandatory=$true, ValueFromPipeline=$true)] [object[]] $InputObject
)
begin {
$root = Split-Path -Path $Path -Parent
if ($root -and !(Test-Path -Path $root)) { New-Item -Path $root -Type Directory
| Out-Null }
}
process {
$InputObject |
Add-Timestamp |
Tee-Object -File $Path -Append
}
}
Publish-DatabaseProject -ErrorVariable DeployError 2>&1 |
Write-LogFile -Path "C:\output.log"
if ($DeployError -and $DeployError.Count -ne 0)
{
Write-Output "Failed"
} else
{
Write-Output "Succeeded"
}
The query in question is executing against a non-existent table. The text output shows:
[2015-12-11T14:42:45.1973944+00:00] Msg 4902, Level 16, State 1, Server ABDN-DEV-PC1, Line 1
[2015-12-11T14:42:45.2053944+00:00] Cannot find the object "xx" because it does not exist or you do not have permission
s.
Succeeded
I am expecting the last line to read: Failed.
If you run the sqlcmd line on its own, and follow it up with $LastExitCode, it does spit out a non-zero exit code.
> sqlcmd -S . -b -v DatabaseName=Integration -q "alter table xx add test Varchar(10)"
Msg 4902, Level 16, State 1, Server ABDN-DEV-PC1, Line 1
Cannot find the object "xx" because it does not exist or you do not have permissions.
> $LastExitCode
1
For various reasons, we cannot use Invoke-SqlCmd, and need to stick with SQLCMD.exe.
How can we make exceptions from within SQLCMD bubble out correctly to the calling script?

Answer 1

Your -ErrorVariable DeployError statement would only get triggered if the Publish-DatabaseProject cmdlet itself fails to execute. As that function is mostly a wrapper around sqlcmd.exe, there isn't any intelligence to bubble up this error. We can wrap it though by using the $LastExitCode automatic variable.
function Publish-DatabaseProject
{
sqlcmd -S . -b -v DatabaseName=Integration -q "alter table xx add test Varchar(10)"
if ($LastExitCode -ne 0)
{
Write-error $LastExitCode
throw $LastExitCode
}
}
Now, PowerShell will catch this error from the .exe, and you can use -ErrorVariable.
Update
So, since you want to keep running and not abandon ship when enountering an error, we need to wrap your Publish-DataBaseProject function with a try{}catch{} block, to catch the error we're generating, without stopping execution.
try {Publish-DatabaseProject -ErrorAction STOP -ErrorVariable DeployError 2>&1 |
Write-LogFile -Path "C:\output.log" }
catch{
Write-Output "Current job $($_), failed"
Write-Output "Exception $($Error.ExceptionID)"
}
Now we're properly generating an exception from a CMD, bubbling it up through our Function, and handling it as if it were a normal function, all using Native PowerShell. I believe this is what you were seeking to do. If not, post a gist of the whole script and I'll help you in a more targeted fashion.