Google Cloud Platform for Architects

Cloud functions triggered by GCS object notifications

Similarly, Cloud Functions can also be triggered by changes in Cloud Storage buckets:

1. Write the Cloud Function and save it as index.js:

/** * Background Cloud Function to be triggered by Cloud Storage.. */exports.helloGCS = function (event, callback) { const file = event.data; if (file.resourceState === 'not_exists') { console.log(`File ${file.name} deleted.`); } else if (file.metageneration === '1') { // metageneration attribute is updated on metadata changes. // on create value is 1 console.log(`File ${file.name} uploaded.`); } else 

{ console.log(`File ${file.name} metadata updated.`); } callback();};

2. Deploy the Cloud Function:

gcloud beta functions deploy helloGCS --trigger-bucket ...