WSO2 G-Reg REST APIs - Import Schema

I have been looking through the REST API documentation for both the Registry and the Governance APIs and I haven't been able to figure out how import a schema via either REST API. Is this possible?

I can create a REST Service with the governance API but the same process with a schema results in a NullPointerException

TID: [-1234] [] [2016-05-26 16:16:22,436] ERROR {org.wso2.carbon.governance.rest.api.internal.GovernanceExceptionHandler} -  Exception during service invocation  {org.wso2.carbon.governance.rest.api.internal.GovernanceExceptionHandler}
        org.wso2.carbon.governance.api.exception.GovernanceException: Error occurred while adding the resource.
        at org.wso2.carbon.governance.rest.api.Asset.importResourceWithRegistry(Asset.java:531)
        at org.wso2.carbon.governance.rest.api.Asset.createGovernanceAsset(Asset.java:469)
        at org.wso2.carbon.governance.rest.api.Asset.createAsset(Asset.java:158)
        at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
        at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)
        at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
        at java.lang.reflect.Method.invoke(Method.java:606)
        at org.apache.cxf.service.invoker.AbstractInvoker.performInvocation(AbstractInvoker.java:188)
        at org.apache.cxf.service.invoker.AbstractInvoker.invoke(AbstractInvoker.java:104)
        at org.apache.cxf.jaxrs.JAXRSInvoker.invoke(JAXRSInvoker.java:204)
        at org.apache.cxf.jaxrs.JAXRSInvoker.invoke(JAXRSInvoker.java:101)
        at org.apache.cxf.interceptor.ServiceInvokerInterceptor$1.run(ServiceInvokerInterceptor.java:58)
        at org.apache.cxf.interceptor.ServiceInvokerInterceptor.handleMessage(ServiceInvokerInterceptor.java:94)
        at org.apache.cxf.phase.PhaseInterceptorChain.doIntercept(PhaseInterceptorChain.java:272)
        at org.apache.cxf.transport.ChainInitiationObserver.onMessage(ChainInitiationObserver.java:121)
        at org.apache.cxf.transport.http.AbstractHTTPDestination.invoke(AbstractHTTPDestination.java:249)
        at org.apache.cxf.transport.servlet.ServletController.invokeDestination(ServletController.java:248)
        at org.apache.cxf.transport.servlet.ServletController.invoke(ServletController.java:222)
        at org.apache.cxf.transport.servlet.ServletController.invoke(ServletController.java:153)
        at org.apache.cxf.transport.servlet.CXFNonSpringServlet.invoke(CXFNonSpringServlet.java:171)
        at org.apache.cxf.transport.servlet.AbstractHTTPServlet.handleRequest(AbstractHTTPServlet.java:289)
        at org.apache.cxf.transport.servlet.AbstractHTTPServlet.doPost(AbstractHTTPServlet.java:209)
        at javax.servlet.http.HttpServlet.service(HttpServlet.java:646)
        at org.apache.cxf.transport.servlet.AbstractHTTPServlet.service(AbstractHTTPServlet.java:265)
        at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:303)
        at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:208)
        at org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52)
        at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:241)
        at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:208)
        at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:220)
        at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:122)
        at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:613)
        at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:170)
        at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:103)
        at org.wso2.carbon.tomcat.ext.valves.CompositeValve.continueInvocation(CompositeValve.java:99)
        at org.wso2.carbon.tomcat.ext.valves.CarbonTomcatValve$1.invoke(CarbonTomcatValve.java:47)
        at org.wso2.carbon.webapp.mgt.TenantLazyLoaderValve.invoke(TenantLazyLoaderValve.java:57)
        at org.wso2.carbon.tomcat.ext.valves.TomcatValveContainer.invokeValves(TomcatValveContainer.java:47)
        at org.wso2.carbon.tomcat.ext.valves.CompositeValve.invoke(CompositeValve.java:62)
        at org.wso2.carbon.tomcat.ext.valves.CarbonStuckThreadDetectionValve.invoke(CarbonStuckThreadDetectionValve.java:159)
        at org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:950)
        at org.wso2.carbon.tomcat.ext.valves.CarbonContextCreatorValve.invoke(CarbonContextCreatorValve.java:57)
        at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:116)
        at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:421)
        at org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:1074)
        at org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:611)
        at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1739)
        at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.run(NioEndpoint.java:1698)
        at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1145)
        at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615)
        at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61)
        at java.lang.Thread.run(Thread.java:745)
        Caused by: java.lang.NullPointerException
        at org.wso2.carbon.registry.resource.services.utils.GetTextContentUtil.getByteContent(GetTextContentUtil.java:83)

I assume that this is needing some schema file, either specified by a URL or provided as a file. Is this something that I can import via the REST API?

Solution

There are 3 ways to add resources(content type rxts such as wsdl, wadl, xsd and policy) to G-Reg

1. Using registry REST API

2. Using publisher API (G-Reg 5.0.0 or above)

Create Schema:(Upload file)

Request

URL:https://<host>:<port>/publisher/assets/schema/apis/schemas?type=schema

Method: POST
Header:Cookie: JSESSIONID=<SESSION-ID>

Payload:(form data)
schema : schema
schema_file : <schema file name>.xsd
filename : <schema file name>.xsd
schema_file_name : <schema file name>.xsd
file_version : <version>
addNewSchemaFileAssetButton : Create

File Upload:

Upload the schema file. Give the field entry as ‘schema_file’

Response should be:

Status: 200 OK

To upload a zip file just change the schema_file,filename and schema_file_name values with zip file name.(I didn't test this but should work according to the source code.)

3. Using Governance API - only for hosted content type resources. (G-Reg 5.2.0 or above)

What is the version your using? Hope these details will help you!