text: /**
   * Copyright 2017, Google, Inc.
   * Licensed under the Apache License, Version 2.0 (the "License");
   * you may not use this file except in compliance with the License.
   * You may obtain a copy of the License at
   *
   *    http://www.apache.org/licenses/LICENSE-2.0
   *
   * Unless required by applicable law or agreed to in writing, software
   * distributed under the License is distributed on an "AS IS" BASIS,
   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
   * See the License for the specific language governing permissions and
   * limitations under the License.
   */
  
  'use strict';
  
  function updateData (instanceId, databaseId) {
    // [START update_data]
    // Imports the Google Cloud client library
    const Spanner = require('@google-cloud/spanner');
  
    // Instantiates a client
    const spanner = Spanner();
  
    // Uncomment these lines to specify the instance and database to use
    // const instanceId = 'my-instance';
    // const databaseId = 'my-database';
  
    // Gets a reference to a Cloud Spanner instance and database
    const instance = spanner.instance(instanceId);
    const database = instance.database(databaseId);
  
    // Update a row in the Albums table
    // Note: Cloud Spanner interprets Node.js numbers as FLOAT64s, so they
    // must be converted to strings before being inserted as INT64s
    const albumsTable = database.table('Albums');
  
    albumsTable.update([
      { SingerId: '1', AlbumId: '1', MarketingBudget: '100000' },
      { SingerId: '2', AlbumId: '2', MarketingBudget: '500000' }
    ])
    .then(() => {
      console.log('Updated data.');
    });
    // [END update_data]
  }
  
  function insertData (instanceId, databaseId) {
    // [START insert_data]
    // Imports the Google Cloud client library
    const Spanner = require('@google-cloud/spanner');
  
    // Instantiates a client
    const spanner = Spanner();
  
    // Uncomment these lines to specify the instance and database to use
    // const instanceId = 'my-instance';
    // const databaseId = 'my-database';
  
    // Gets a reference to a Spanner instance and database
    const instance = spanner.instance(instanceId);
    const database = instance.database(databaseId);
  
    // Instantiate Spanner table objects
    const singersTable = database.table('Singers');
    const albumsTable = database.table('Albums');
  
    // Inserts rows into the Singers table
    // Note: Cloud Spanner interprets Node.js numbers as FLOAT64s, so
    // they must be converted to strings before being inserted as INT64s
    singersTable.insert([
      { SingerId: '1', FirstName: 'Marc', LastName: 'Richards' },
      { SingerId: '2', FirstName: 'Catalina', LastName: 'Smith' },
      { SingerId: '3', FirstName: 'Alice', LastName: 'Trentor' },
      { SingerId: '4', FirstName: 'Lea', LastName: 'Martin' },
      { SingerId: '5', FirstName: 'David', LastName: 'Lomond' }
    ])
    .then(() => {
      // Inserts rows into the Albums table
      albumsTable.insert([
        { SingerId: '1', AlbumId: '1', AlbumTitle: 'Go, Go, Go' },
        { SingerId: '1', AlbumId: '2', AlbumTitle: 'Total Junk' },
        { SingerId: '2', AlbumId: '1', AlbumTitle: 'Green' },
        { SingerId: '2', AlbumId: '2', AlbumTitle: 'Forever Hold your Peace' },
        { SingerId: '2', AlbumId: '3', AlbumTitle: 'Terrified' }
      ]);
    })
    .then(() => {
      console.log('Inserted data.');
    });
    // [END insert_data]
  }
  
  function queryData (instanceId, databaseId) {
    // [START query_data]
    // Imports the Google Cloud client library
    const Spanner = require('@google-cloud/spanner');
  
    // Instantiates a client
    const spanner = Spanner();
  
    // Uncomment these lines to specify the instance and database to use
    // const instanceId = 'my-instance';
    // const databaseId = 'my-database';
  
    // Gets a reference to a Cloud Spanner instance and database
    const instance = spanner.instance(instanceId);
    const database = instance.database(databaseId);
  
    const query = {
      sql: 'SELECT SingerId, AlbumId, AlbumTitle FROM Albums'
    };
  
    // Queries rows from the Albums table
    database.run(query)
      .then((results) => {
        const rows = results[0];
  
        rows.forEach((row) => {
          const json = row.toJSON();
          console.log(`SingerId: ${json.SingerId.value}, AlbumId: ${json.AlbumId.value}, AlbumTitle: ${json.AlbumTitle}`);
        });
      });
    // [END query_data]
  }
  
  function readData (instanceId, databaseId) {
    // [START read_data]
    // Imports the Google Cloud client library
    const Spanner = require('@google-cloud/spanner');
  
    // Instantiates a client
    const spanner = Spanner();
  
    // Uncomment these lines to specify the instance and database to use
    // const instanceId = 'my-instance';
    // const databaseId = 'my-database';
  
    // Gets a reference to a Cloud Spanner instance and database
    const instance = spanner.instance(instanceId);
    const database = instance.database(databaseId);
  
    // Read rows from the Albums table
    const albumsTable = database.table('Albums');
  
    const query = {
      columns: ['SingerId', 'AlbumId', 'AlbumTitle'],
      keySet: {
        all: true
      }
    };
  
    albumsTable.read(query)
      .then((results) => {
        const rows = results[0];
  
        rows.forEach((row) => {
          const json = row.toJSON();
          console.log(`SingerId: ${json.SingerId.value}, AlbumId: ${json.AlbumId.value}, AlbumTitle: ${json.AlbumTitle}`);
        });
      });
    // [END read_data]
  }
  
  const cli = require(`yargs`)
    .demand(1)
    .command(
      `update <instanceName> <databaseName>`,
      `Modifies existing rows of data in an example Cloud Spanner table.`,
      {},
      (opts) => updateData(opts.instanceName, opts.databaseName)
    )
    .command(
      `query <instanceName> <databaseName>`,
      `Executes a read-only SQL query against an example Cloud Spanner table.`,
      {},
      (opts) => queryData(opts.instanceName, opts.databaseName)
    )
    .command(
      `insert <instanceName> <databaseName>`,
      `Inserts new rows of data into an example Cloud Spanner table.`,
      {},
      (opts) => insertData(opts.instanceName, opts.databaseName)
    )
    .command(
      `read <instanceName> <databaseName>`,
      `Reads data in an example Cloud Spanner table.`,
      {},
      (opts) => readData(opts.instanceName, opts.databaseName)
    )
    .example(`node $0 update "my-instance" "my-database"`)
    .example(`node $0 query "my-instance" "my-database"`)
    .example(`node $0 insert "my-instance" "my-database"`)
    .example(`node $0 read "my-instance" "my-database"`)
    .wrap(120)
    .recommendCommands()
    .epilogue(`For more information, see https://cloud.google.com/spanner/docs`);
  
  if (module === require.main) {
    cli.help().strict().argv; // eslint-disable-line
  }
  