Is there a way to call SSDT DacServices without a connectionstring - powershell

Question

I have a Source DacPac and a Target DacPac. With powershell I would like to compare both and generate a upgrade script. This per se is simple for all cases with DacServices as long as there is a valid Connection String. However, for my CD pipeline, I do not know the eventual connection string nor do I wish to know. And all I want is for the script to generate the SQL.
I tried this out with sqlpackage.exe by sending args as follows
$args = #(
"/a:Script",
"/sf:$PathToDacpacSource",
"/tf:$PathToDacpacTarget",
"/op:$outputFile",
"/tdn:$TargetDatabaseName"
)
and this works fine. so far I had managed by adding just a dependency to DacServices via [Microsoft.SqlServer.DacFx.x64], but this inability to generate scripts without a connection string has forced me to add the dependency on SQLPackage.exe via [Microsoft.Data.Tools.Msbuild] too
The constructors for DacServices all require a ConnectionString
Has anyone else encountered a similar situation and any solutions?
or Do you exclusively use SQLPackage at the deployment side to overcome this issue?

Answer 1

There is a static version of GenerateDeployScript that does not need a connection string as you don't call the constructor for a static method, it isn't very clear in the msdn documentation but the "S" which looks like it is floating means it is static :)
https://msdn.microsoft.com/en-us/library/microsoft.sqlserver.dac.dacservices.generatedeployscript(v=sql.120).aspx#M:Microsoft.SqlServer.Dac.DacServices.GenerateDeployScript%28Microsoft.SqlServer.Dac.DacPackage,Microsoft.SqlServer.Dac.DacPackage,System.String,Microsoft.SqlServer.Dac.DacDeployOptions%29
` public static string GenerateDeployScript( DacPackage sourcePackage, DacPackage targetPackage, string targetDatabaseName, DacDeployOptions options = null )