Class DataSourceSpecBuilder

const spec = SpreadsheetApp.newDataSourceSpec()
                 .asLooker()
                 .setInstanceUrl('https://looker_instance_url.com')
                 .setModelName('model_name')
                 .setExploreName('explore_name')
                 .build();

const bigQueryDataSourceSpec = SpreadsheetApp.newDataSourceSpec().asBigQuery();
// TODO(developer): Replace with the required dataset, project and table IDs.
bigQueryDataSourceSpec.setDatasetId('my data set id');
bigQueryDataSourceSpec.setProjectId('my project id');
bigQueryDataSourceSpec.setTableId('my table id');

bigQueryDataSourceSpec.build();

const lookerDataSourceSpecBuilder =
    SpreadsheetApp.newDataSourceSpec().asLooker();
const lookerSpec = lookerDataSourceSpecBuilder.setExploreName('my explore name')
                       .setInstanceUrl('my instance url')
                       .setModelName('my model name')
                       .build();

// TODO(developer): Replace the URL with your own.
const ss = SpreadsheetApp.openByUrl(
    'https://docs.google.com/spreadsheets/d/abc123456/edit',
);
const spec = ss.getDataSources()[0].getSpec();

const newSpec = spec.copy();

// TODO(developer): Replace the URL with your own.
const ss = SpreadsheetApp.openByUrl(
    'https://docs.google.com/spreadsheets/d/abc123456/edit',
);
const spec = ss.getDataSources()[0].getSpec();
const parameters = spec.getParameters();

// TODO(developer): Replace the URL with your own.
const ss = SpreadsheetApp.openByUrl(
    'https://docs.google.com/spreadsheets/d/abc123456/edit',
);
const spec = ss.getDataSources()[0].getSpec();
const type = spec.getType();

const specBuilder = SpreadsheetApp.newDataSourceSpec();
specBuilder.removeAllParameters();

const specBuilder = SpreadsheetApp.newDataSourceSpec();
specBuilder.removeParameter('x');

const specBuilder = SpreadsheetApp.newDataSourceSpec().asBigQuery();
specBuilder.setParameterFromCell('x', 'A1');
const bigQuerySpec = specBuilder.build();