Merge pull request #123 from dgraph-io/rajas/add_example

Add dropOp mutation to example

Author: vmrajas

examples/simple/README.md

@@ -73,6 +73,24 @@ Number of people named "Alice": 1
   dob: '1980-02-01T17:30:00Z',
   friend: [ { name: 'Bob', age: 24 }, { name: 'Charlie', age: 29 } ],
   school: [ { name: 'Crown Public School' } ] }
+Number of people named "Alice": 0
+Created person named "Alice" with uid = 0x19
+
+All created nodes (map from blank node names to uids):
+alice => 0x19
+dg.3973478125.10 => 0x16
+dg.3973478125.11 => 0x17
+dg.3973478125.12 => 0x18
+
+Number of people named "Alice": 1
+{ uid: '0x19',
+  name: 'Alice',
+  age: 26,
+  married: true,
+  loc: { type: 'Point', coordinates: [ 1.1, 2 ] },
+  dob: '1980-02-01T17:30:00Z',
+  friend: [ { name: 'Bob', age: 24 }, { name: 'Charlie', age: 29 } ],
+  school: [ { name: 'Crown Public School' } ] }
 
 DONE!
 ```

examples/simple/index.js

@@ -3,21 +3,28 @@ const grpc = require("grpc");
 
 // Create a client stub.
 function newClientStub() {
-    return new dgraph.DgraphClientStub("localhost:9080", grpc.credentials.createInsecure());
+    return new dgraph.DgraphClientStub("localhost:9080");
 }
 
 // Create a client.
 function newClient(clientStub) {
     return new dgraph.DgraphClient(clientStub);
 }
 
-// Drop All - discard all data and start from a clean slate.
+// Drop All - discard all data, schema and start from a clean slate.
 async function dropAll(dgraphClient) {
     const op = new dgraph.Operation();
     op.setDropAll(true);
     await dgraphClient.alter(op);
 }
 
+// Drop All Data, but keep the schema.
+async function dropData(dgraphClient) {
+    const op = new dgraph.Operation();
+    op.setDropOp(dgraph.Operation.DropOp.DATA);
+    await dgraphClient.alter(op);
+}
+
 // Set schema.
 async function setSchema(dgraphClient) {
     const schema = `
@@ -125,6 +132,10 @@ async function main() {
     await setSchema(dgraphClient);
     await createData(dgraphClient);
     await queryData(dgraphClient);
+    await dropData(dgraphClient);
+    await queryData(dgraphClient);
+    await createData(dgraphClient);
+    await queryData(dgraphClient);
 
     // Close the client stub.
     dgraphClientStub.close();