Add support of multiple credentials for ssh-agent-credentials wrapper

ssh-agent-credentials wrapper supports multiple credentials like
ssh-agent plugin v1.5
(https://wiki.jenkins-ci.org/display/JENKINS/SSH+Agent+Plugin)
via 'users' parameter. 'user' parameter is retained for backward
compatibility.

Change-Id: I8a21dd0e7cba210818ffe30bbc5c7e73b56211cb
Signed-off-by: Igor Gnatenko <ignatenko@mirantis.com>

jenkins_jobs/modules/wrappers.py

@@ -1154,23 +1154,66 @@ def ssh_agent_credentials(parser, xml_parent, data):
 
     Requires the Jenkins :jenkins-wiki:`SSH-Agent Plugin <SSH+Agent+Plugin>`.
 
-    :arg str user: The user id of the jenkins user credentials (required)
+    :arg list users: A list of Jenkins users credential IDs (required)
+    :arg str user: The user id of the jenkins user credentials (deprecated)
 
     Example:
 
+    .. literalinclude::
+            /../../tests/wrappers/fixtures/ssh-agent-credentials002.yaml
+
+
+    if both **users** and **user** parameters specified, **users** will be
+        prefered, **user** will be ignored.
+
+    Example:
+
+    .. literalinclude::
+            /../../tests/wrappers/fixtures/ssh-agent-credentials003.yaml
+
+    The **users** with one value in list equals to the **user**. In this
+    case old style XML will be generated. Use this format if you use
+    SSH-Agent plugin < 1.5.
+
+    Example:
+
+    .. literalinclude::
+            /../../tests/wrappers/fixtures/ssh-agent-credentials004.yaml
+
+    equals to:
+
     .. literalinclude::
             /../../tests/wrappers/fixtures/ssh-agent-credentials001.yaml
 
     """
 
+    logger = logging.getLogger(__name__)
+
     entry_xml = XML.SubElement(
         xml_parent,
         'com.cloudbees.jenkins.plugins.sshagent.SSHAgentBuildWrapper')
+    xml_key = 'user'
 
-    try:
-        XML.SubElement(entry_xml, 'user').text = data['user']
-    except KeyError:
-        raise JenkinsJobsException("Missing 'user' for ssh-agent-credentials")
+    user_list = list()
+    if 'users' in data:
+        user_list += data['users']
+        if len(user_list) > 1:
+            entry_xml = XML.SubElement(entry_xml, 'credentialIds')
+            xml_key = 'string'
+        if 'user' in data:
+            logger.warn("Both 'users' and 'user' parameters specified for "
+                        "ssh-agent-credentials. 'users' is used, 'user' is "
+                        "ignored.")
+    elif 'user' in data:
+        logger.warn("The 'user' param has been deprecated, "
+                    "use the 'users' param instead.")
+        user_list.append(data['user'])
+    else:
+        raise JenkinsJobsException("Missing 'user' or 'users' parameter "
+                                   "for ssh-agent-credentials")
+
+    for user in user_list:
+        XML.SubElement(entry_xml, xml_key).text = user
 
 
 def credentials_binding(parser, xml_parent, data):

tests/wrappers/fixtures/ssh-agent-credentials002.xml

@@ -0,0 +1,12 @@
+<?xml version="1.0" encoding="utf-8"?>
+<project>
+  <buildWrappers>
+    <com.cloudbees.jenkins.plugins.sshagent.SSHAgentBuildWrapper>
+      <credentialIds>
+        <string>44747833-247a-407a-a98f-a5a2d785111c</string>
+        <string>f1c0f777-7ac6-43fd-b5c7-68b420aa1392</string>
+        <string>dd647a01-be21-402b-bfc5-a4e89be7d0c4</string>
+      </credentialIds>
+    </com.cloudbees.jenkins.plugins.sshagent.SSHAgentBuildWrapper>
+  </buildWrappers>
+</project>

tests/wrappers/fixtures/ssh-agent-credentials002.yaml

@@ -0,0 +1,6 @@
+wrappers:
+  - ssh-agent-credentials:
+        users:
+            - '44747833-247a-407a-a98f-a5a2d785111c'
+            - 'f1c0f777-7ac6-43fd-b5c7-68b420aa1392'
+            - 'dd647a01-be21-402b-bfc5-a4e89be7d0c4'

tests/wrappers/fixtures/ssh-agent-credentials003.xml

@@ -0,0 +1,11 @@
+<?xml version="1.0" encoding="utf-8"?>
+<project>
+  <buildWrappers>
+    <com.cloudbees.jenkins.plugins.sshagent.SSHAgentBuildWrapper>
+      <credentialIds>
+        <string>44747833-247a-407a-a98f-a5a2d785111c</string>
+        <string>dd647a01-be21-402b-bfc5-a4e89be7d0c4</string>
+      </credentialIds>
+    </com.cloudbees.jenkins.plugins.sshagent.SSHAgentBuildWrapper>
+  </buildWrappers>
+</project>

tests/wrappers/fixtures/ssh-agent-credentials003.yaml

@@ -0,0 +1,6 @@
+wrappers:
+    - ssh-agent-credentials:
+        user: '49d20745-9889-4c02-b286-fc6fb89c36bd'
+        users:
+            - '44747833-247a-407a-a98f-a5a2d785111c'
+            - 'dd647a01-be21-402b-bfc5-a4e89be7d0c4'

tests/wrappers/fixtures/ssh-agent-credentials004.xml

@@ -0,0 +1,8 @@
+<?xml version="1.0" encoding="utf-8"?>
+<project>
+  <buildWrappers>
+    <com.cloudbees.jenkins.plugins.sshagent.SSHAgentBuildWrapper>
+      <user>49d20745-9889-4c02-b286-fc6fb89c36bd</user>
+    </com.cloudbees.jenkins.plugins.sshagent.SSHAgentBuildWrapper>
+  </buildWrappers>
+</project>

tests/wrappers/fixtures/ssh-agent-credentials004.yaml

@@ -0,0 +1,4 @@
+wrappers:
+  - ssh-agent-credentials:
+      users:
+          - '49d20745-9889-4c02-b286-fc6fb89c36bd'