Automatic deployment of snapshots to Sonatype by Travis-CI

Snapshots are deployed to the Sonatype Maven repository after every
successful Travis-CI test build, analogous to echo3.

Resolves echo3#12

.travis.yml

@@ -1 +1,15 @@
-language: java
+language: java
+
+# Snapshot deployment to Sonatype Maven repository
+# The password is encrypted using "travis encrypt -r echo3/echo3extras SONATYPE_PASSWORD=password"
+# and only decrypted and set as environment variable by travis-ci if the build runs in the context of
+# the echo3/echo3extras github repository.
+
+env:
+  global:
+  - SONATYPE_USERNAME=bschmid
+  - secure: "WkgVn7wbMe7C1KKAFZrvy2BR2eZZ6Bnv1/BPJFHOI+u172wnFPX5FDyjZQiU9xipocnWfa5MZCCpyKBJrNDnWEVlM75bZG6Xpq+yu3tbZgxyNZ3JLxU6a7m5OJo4XjhBiVbX7b+BmD5qHCO5CTgxZIJbKIz0ToUU+ALLcdVlsS8="
+
+after_success:
+- python resource/travis-ci/addServer.py
+- ant travis.mvn.snapshot

build.xml

@@ -414,8 +414,24 @@
         </artifact:install>
     </target>
 
-    <target name="mvn.snapshot" depends="dist, doc.jars, -mvn.generate.pom, -mvn.inittasks"
+    <!-- Deploy snapshot to Sonatype Maven repository. Called by Travis-CI -->
+    <target name="travis.mvn.snapshot">
+        <property environment="env"/>
+        <condition property="secure_env">
+            <not>
+                <equals arg1="${env.TRAVIS_SECURE_ENV_VARS}" arg2="false"/>
+            </not>
+        </condition>
+        <fail unless="secure_env" message="No secure environment variables available, skipping snapshot deployment" />
+        <antcall target="-mvn.snapshot" />
+    </target>
+
+    <target name="mvn.snapshot" depends="dist, doc.jars, -mvn.snapshot"
             description="Deploy snapshot version to configured Maven snapshot repository">
+    </target>
+
+    <!-- Synthetic Implementation target for code reuse -->
+    <target name="-mvn.snapshot" depends="-mvn.generate.pom, -mvn.inittasks">
         <!-- The artifact:deploy tasks do not repesct settings.xml for proxy/auth, so we use the mvn task -->
         <!-- Deploy Echo API module. -->
         <artifact:mvn>

resource/travis-ci/addServer.py

@@ -0,0 +1,50 @@
+#!/usr/bin/env python
+"""
+    Add sonatype snapshot server and credentials to ~/.m2/settings.xml
+    Username and password are passed in by travis-ci as environment
+    variables.
+"""
+import sys
+import os
+import os.path
+import xml.dom.minidom
+
+if os.environ["TRAVIS_SECURE_ENV_VARS"] == "false":
+  print "no secure env vars available, skipping deployment"
+  sys.exit()
+
+homedir = os.path.expanduser("~")
+
+m2 = xml.dom.minidom.parse(homedir + '/.m2/settings.xml')
+settings = m2.getElementsByTagName("settings")[0]
+
+serversNodes = settings.getElementsByTagName("servers")
+if not serversNodes:
+  serversNode = m2.createElement("servers")
+  settings.appendChild(serversNode)
+else:
+  serversNode = serversNodes[0]
+
+sonatypeServerNode = m2.createElement("server")
+sonatypeServerId = m2.createElement("id")
+sonatypeServerUser = m2.createElement("username")
+sonatypeServerPass = m2.createElement("password")
+
+idNode = m2.createTextNode("sonatype-nexus-snapshots")
+userNode = m2.createTextNode(os.environ["SONATYPE_USERNAME"])
+passNode = m2.createTextNode(os.environ["SONATYPE_PASSWORD"])
+
+sonatypeServerId.appendChild(idNode)
+sonatypeServerUser.appendChild(userNode)
+sonatypeServerPass.appendChild(passNode)
+
+sonatypeServerNode.appendChild(sonatypeServerId)
+sonatypeServerNode.appendChild(sonatypeServerUser)
+sonatypeServerNode.appendChild(sonatypeServerPass)
+
+serversNode.appendChild(sonatypeServerNode)
+
+m2Str = m2.toxml()
+f = open(homedir + '/.m2/settings.xml', 'w')
+f.write(m2Str + '\n')
+f.close()