title: NodeJS gRPC: "Method handler expected but not provided"
body: <p>I plowed through the docs and haven't found a solution yet. The app is loosely based on the <a href="http://www.grpc.io/docs/quickstart/node.html" rel="nofollow noreferrer">"sayHello"-example</a> from their docs but every time the code runs the warning <code>Method handler for /eventComm.DatabaseRPC/InsertSingleDocument expected but not provided</code> is returned.</p>
  
  <p>My proto file:</p>
  
  <pre class="lang-proto prettyprint-override"><code>service DatabaseRPC {
    rpc InsertSingleDocument (Doc) returns (Doc) {} 
  }
  
  message Doc {
    required string name = 1;
    required int32 id = 2;
  }
  </code></pre>
  
  <p>My gRPC Server:</p>
  
  <pre class="lang-js prettyprint-override"><code>  function InsertSingleDocument (call, callback) {
      callback(null, {
        name: 'Hello ',
        id: 1
      })
    }
    let server = new grpc.Server()
    server.addProtoService(protoDef.DatabaseRPC.service, {
      InsertSingleDocument: InsertSingleDocument
    })
    server.bind('0.0.0.0:50051', grpc.ServerCredentials.createInsecure())
    server.start()
  </code></pre>
  
  <p>What is the problem with this code? Of course I already tried to <a href="https://www.google.de/search?q=nodejs%20grpc%20methodhandler%20expected%20but%20not%20found&amp;oq=nodejs%20grpc%20method%20handler%20expected%20but%20not%20found" rel="nofollow noreferrer">google the error</a> but found no solution</p>