Hi all, Currently, if a required option is missing for a Beam pipeline, the error message is like
> > Exception in thread "main" java.lang.IllegalArgumentException: Missing > required value for [public abstract java.lang.String > org.apache.beam.examples.WordCount$WordCountOptions.getOutput(), "Path of > the file to write to"]. This is quite long but doesn't give any hint to users about the required option. Instead, I'm thinking about something like Exception in thread "main" java.lang.IllegalArgumentException: Missing > required option [--output, "Path of the file to write to"]. It can be achieved by adding a method that *returns the option from a method* to ProxyInvocationHandler <https://github.com/apache/beam/blob/master/sdks/java/core/src/main/java/org/apache/beam/sdk/options/ProxyInvocationHandler.java> class. public String getOption(Method method) { return gettersToPropertyNames.get(method.getName()); } This may look general for ProxyInvocationHandler but you get the idea. WDYT? Thanks, Manu
