"Entity is not api accessible" when using the Metadata API

Question

I'm attempting to use the Metadata API to add a custom button to my contact layout:

https://github.com/financialforcedev/apex-mdapi/

I'm following the example written here: https://andyinthecloud.com/2014/04/24/apex-metadata-api-and-spring14-keys-to-the-kingdom/

To begin, I copied the MetadataService.cls and MetadataServiceTest.cls into my force.com developer instance. Then, I attempted to run through the example by first creating a webLink MetadataService, however when I get to the last line it gets stuck:

MetadataService.WebLink webLink = new MetadataService.WebLink();
webLink.fullName = 'Test__c.googleButton';
webLink.availability = 'online';
webLink.displayType = 'button';
webLink.encodingKey = 'UTF-8';
webLink.hasMenubar = false;
webLink.hasScrollbars = true;
webLink.hasToolbar = false;
webLink.height = 600;
webLink.isResizable = true;
webLink.linkType = 'url';
webLink.masterLabel = 'google';
webLink.openType = 'newWindow';
webLink.position = 'none';
webLink.protected_x = false;
webLink.showsLocation = false;
webLink.showsStatus = false;
webLink.url = 'http://www.google.com';
webLink.width = 600;
service.createMetadata(new List<MetadataService.Metadata> { webLink })[0];

I am getting the error "Entity is not api accessible". This is my first time using the Metadata API and I'm not really sure how to troubleshoot this. Any suggestions?

Answer 1

You get that error because you haven't instantiated service to anything. You could reproduce the error with this simple snippet as your entire execution:

service.doSomething();

You need to create a new MetadataPort to call the createMetadata method.

MetadataService.MetadataPort service = new MetadataService.MetadataPort();
List<MetadataService.Metadata> elements = List<MetadataService.Metadata> { webLink };
MetadataService.SaveResult result = service.createMetadata(elements)[0];

I found this class by simply searching the MetadatService class for createMetadata(.