How can I create a JSON webservice to store and retrieve data from a simple properties file? - web-services

Question

How can I create a Java or Javascript JSON webservice to retrieve data from a simple properties file? My intention is to uses this as a global property storage for a Jenkins instance that runs many Unit tests. The master property file also needs to be capable of being manually edited and stored in source control.
I am just wondering what method people would recommend that would be the easiest for a junior level programmer like me. I need read capability at miniumum but, and if its not too hard, write capability also. Therefore, that means it is not required to be REST.
If something like this already exists in Java or Groovy, a link to that resource would be appreciated. I am a SoapUI expert but I am unsure if a mock service could do this sort of thing.
I found something like this in Ruby but I could not get it to work as I am not a Ruby programmer at all.

Answer 1

There are a multitude of Java REST frameworks, but I'm most familiar with Jersey so here's a Groovy script that gives a simple read capability to a properties file.
#Grapes([
#Grab(group='org.glassfish.jersey.containers', module='jersey-container-grizzly2-http', version='2.0'),
#Grab(group='org.glassfish.jersey.core', module='jersey-server', version='2.0'),
#Grab(group='org.glassfish.jersey.media', module='jersey-media-json-jackson', version='2.0')
])
import org.glassfish.jersey.grizzly2.httpserver.GrizzlyHttpServerFactory
import org.glassfish.jersey.jackson.JacksonFeature
import javax.ws.rs.GET
import javax.ws.rs.Path
import javax.ws.rs.Produces
#Path("properties")
class PropertiesResource {
#GET
#Produces("application/json")
Properties get() {
new File("test.properties").withReader { Reader reader ->
Properties p = new Properties()
p.load(reader)
return p
}
}
}
def rc = new org.glassfish.jersey.server.ResourceConfig(PropertiesResource, JacksonFeature);
GrizzlyHttpServerFactory.createHttpServer('http://localhost:8080/'.toURI(), rc).start()
System.console().readLine("Press any key to exit...")
Unfortunately, since Jersey uses the 3.1 version of the asm library, there are conflicts with Groovy's 4.0 version of asm unless you run the script using the groovy-all embeddable jar (it won't work by just calling groovy on the command-line and passing the script). I also had to supply an Apache Ivy dependency. (Hopefully the Groovy team will resolve these in the next release--the asm one in particular has caused me grief in the past.) So you can call it like this (supply the full paths to the classpath jars):
java -cp ivy-2.2.0.jar:groovy-all-2.1.6.jar groovy.lang.GroovyShell restProperties.groovy
All you have to do is create a properties file named test.properties, then copy the above script into a file named restProperties.groovy, then run via the above command line. Then you can run the following in Unix to try it out.
curl http://localhost:8080/properties
And it will return a JSON map of your properties file.