Node.js querying

A simple query can be performed by passing a CQL query to the client using the executeQuery() function for standard query execution:

// For Stargate OSS: SELECT the data to read from the table
const query = new Query();
const queryString = 'SELECT firstname, lastname FROM test.users;'
// Set the CQL statement using the string defined in the last line
query.setCql(queryString);

// For Stargate OSS: execute the query statement
const response = await promisifiedClient.executeQuery(
  query,
  authenticationMetadata
);

console.log("select executed")

Data definition (DDL) queries are supported in the same manner:

// For Stargate OSS: Create a new keyspace
const createKeyspaceStatement = new Query();
// Set the CQL statement
createKeyspaceStatement.setCql("CREATE KEYSPACE IF NOT EXISTS test WITH REPLICATION = {'class' : 'SimpleStrategy', 'replication_factor' : 1};");

await promisifiedClient.executeQuery(createKeyspaceStatement, authenticationMetadata);

console.log("created keyspace");

// For Stargate OSS: Create a new table
const createTableStatement = new Query();
// Set the CQL statement
createTableStatement.setCql("CREATE TABLE IF NOT EXISTS test.users (firstname text PRIMARY KEY, lastname text);");

await promisifiedClient.executeQuery(
  createTableStatement,
  authenticationMetadata
);

console.log("created table");

Parameterized queries are also supported:

const query = new Query();
query.setCql("select * from system_schema.keyspaces where keyspace_name = ?");

const keyspaceNameValue = new Value();
keyspaceNameValue.setString("system");

const queryValues = new Values();
queryValues.setValuesList([keyspaceNameValue]);

query.setValues(queryValues);

const queryParameters = new QueryParameters();
queryParameters.setTracing(false);
queryParameters.setSkipMetadata(false);

query.setParameters(queryParameters);

const response = await promisifiedClient.executeQuery(query, metadata);

If you would like to use a batch statement, the client also provides an executeBatch() function to execute a batch query:

// For Stargate OSS: INSERT two rows/records
 // Create two queries that will be run in a batch statement
 const insertOne = new BatchQuery();
 const insertTwo = new BatchQuery();

 // Set the CQL statement
 insertOne.setCql(`INSERT INTO test.users (firstname, lastname) VALUES('Jane', 'Doe')`);
 insertTwo.setCql(`INSERT INTO test.users (firstname, lastname) VALUES('Serge', 'Provencio')`);

 // Define the new batch to include the 2 insertions
 const batch = new Batch();
 batch.setQueriesList([insertOne, insertTwo]);

 // For Stargate OSS: execute the batch statement
 const batchResult = await promisifiedClient.executeBatch(
   batch,
   authenticationMetadata
 );
 console.log("inserted data");

Promise support

The Node gRPC implementation uses callbacks by default. If you’d prefer promises, this library provides a utility function to create a promisified version of the Stargate gRPC client. The promise will reject if an error occurs:

import {
  StargateClient,
  promisifyStargateClient,
} from "@stargate-oss/stargate-grpc-node-client";

const stargateClient = new StargateClient(
  "localhost:8090",
  grpc.credentials.createInsecure()
);

const promisifiedClient = promisifyStargateClient(stargateClient);
try {
  const queryResult = await promisifiedClient.executeQuery(
    query,
    metadata,
    callOptions
  );
  const batchResult = await promisifiedClient.executeBatch(
    query,
    metadata,
    callOptions
  );
} catch (e) {
  // something went wrong
}

The metadata and callOptions arguments are both optional.