Class RelationshipsApi

const relationships = [
  {
     externalId: 'some_relationship',
     sourceExternalId: 'some_source_external_id',
     sourceType: 'asset' as const,
     targetExternalId: 'some_target_external_id',
     targetType: 'event' as const
  }
];
const createdRelationships = await client.relationships.create(relationships);

await client.relationships.delete([{externalId: 'abc'}, {externalId: 'def'}]);

const relationships = await client.relationships.list({ filter: { createdTime: { min: new Date('1 jan 2018'), max: new Date('1 jan 2019') }}});

const relationships = await client.relationships.retrieve([{externalId: 'abc'}, {externalId: 'def'}]);