TCAP Usage via REST Request

Hello,

Here is a problem I encountered using TCAP 2.4.0 on Teamcity v 2017.1.4

I'm creating a "command line" type build step using the REST web services of Teamcity.
I set the artifactory parameters by adding the following properties to the REST request :

• org.jfrog.artifactory.selectedDeployableServer.deployerUsername
• secure:org.jfrog.artifactory.selectedDeployableServer.deployerPassword
• org.jfrog.artifactory.selectedDeployableServer.envVarsExcludePatterns
• org.jfrog.artifactory.selectedDeployableServer.downloadSpecSource
• org.jfrog.artifactory.selectedDeployableServer.overrideDefaultDeployerCredentials
• org.jfrog.artifactory.selectedDeployableServer.publishBuildInfo
• org.jfrog.artifactory.selectedDeployableServer.uploadSpec
• org.jfrog.artifactory.selectedDeployableServer.urlId
• org.jfrog.artifactory.selectedDeployableServer.useSpecs

The "org.jfrog.artifactory.selectedDeployableServer.uploadSpec" parameter is set to "true". So I want to download and upload by
Specs. In the GUI, it is not necessary to specify the target repository in this case.
When I create the step via the Teamcity REST Api, the build can't be started with the following error :
"Missing or invalid build configuration parameters: org.jfrog.artifactory.selectedDeployableServer.targetRepo: Please select a target repository."

Creating the same step using the GUI is OK and the build starts.

It seems that the "org.jfrog.artifactory.selectedDeployableServer.targetRepo" is automatically added to the step parameters when the step is created using the GUI.
(verified with a REST GET Request on that step)
For a REST usage, I have to add it to my request, althought I want a "Specs" upload/download.

As you already guessed the problem is that the parameters provided in both cases (REST vs GUI) are not the same.