Custom Operator Troubleshooting Tips

Custom-Operator-Troubleshooting-Tips

My operator won't upload

Problem: After compiling the operator successfully, the progress bar "zips by" in the blink of an eye at the upload dialog and the JAR never appears in the list of uploaded JARs.

Cause: While the operator did compile successfully, it is not able to successfully reference the Signature class from the plugins.xml file. 

Solution: Verify that the complete classpath of the Signature class is included in the  plugins.xml file. If the name of your Signature class is MySignature and the name of your package is com.mycompany.plugins, then it should look like this:

<?xml version="1.0" encoding="UTF-8"?>
<alpine-plugins>
 <plugin>
   <signature-class>com.mycompany.plugins.MySignature</signature-class>
 </plugin>
</alpine-plugins>

IntelliJ won't build my samples/operators

Problem: IntelliJ displays errors and does not show option for Maven build commands.

Cause: You need to install the Scala and Maven plugins for IntelliJ. 

Solution: Open Preferences in IntelliJ, and ensure that 'Maven Integration' and 'Scala' are checked. If they are not, search for them from this dialog and install them.

"nodename nor servname provided, or not known" errors when building samples (failing tests)

Problem: When trying to build the custom operator samples, all the tests fail with the error "nodename nor servname provided, or not known".

Cause: There is a bug in some versions of JDK 7 on OSX where it does not know how to associate the computer's hostname with the localhost IP (127.0.0.1).

Solution: Add the following line to /etc/hosts (you must have administrator privileges to edit this file):

127.0.0.1 myhostnamehere

echo $HOSTNAME