Build A Serverless Data Pipeline Lorna Mitchell, IBM
A presentation at CloudConf.IT in April 2018 in Turin, Metropolitan City of Turin, Italy by Lorna Jane Mitchell
Build A Serverless Data Pipeline Lorna Mitchell, IBM
Stackoverflow Dashboard @lornajane
Pipeline To Shift Data Bringing data from StackOverflow into the dashboard my advocate team uses @lornajane
What is Serverless? Backend functions, deployed to the cloud, scaling on demand. Pay as you go. @lornajane
The Serverless Revolution FaaS: Functions as a Service Developer focus: • the outputs • the inputs • the logic in between Charges are usually per GBsec @lornajane
Why Go Serverless? • Costs nothing when idle • Small application, simple architecture • Bursty usage since it runs from a cron • No real-time requirement • Easily within free tier @lornajane
An Aside About Databases @lornajane
Document Databases Store collections of schemaless documents, in JSON @lornajane
Apache CouchDB Cluster of Unreliable Commodity Hardware • Modern, robust, scalable document database • HTTP API • JSON data format • Best replication on the planet (probably) @lornajane
OfflineFirst Applications This app is OfflineFirst: • Client side JS • Client side copy of DB using PouchDB • Background sync to serverside CouchDB @lornajane
Writing Serverless Functions @lornajane
Serverless Platforms • Amazon Lambda • IBM Cloud Functions (aka OpenWhisk) • Twilio Functions • Azure Functions • Google Cloud Functions • … and more every week @lornajane
Hello World in JS All the platforms are slightly different, this is for OpenWhisk exports.main = function(args) { return({“message”: “Hello, World!”}); }; Function must return an object or a Promise @lornajane
OpenWhisk Vocabulary • trigger an event, such as an incoming HTTP request • rule map a trigger to an action • action a function, optionally with parameters • package collect actions and parameters together • sequence more than one action in a row • cold start time to run a fresh action @lornajane
Working With Actions Deploy code: zip hello.zip index.js bx wsk action update —kind nodejs:6 demo/hello1 hello.zip Then run it: bx wsk action invoke —blocking demo/hello1 @lornajane
Web-Enabled Actions Deploy code: zip hello.zip index.js bx wsk action update —kind nodejs:6 —web true demo/hello1 hello. Then curl it: curl https://openwhisk.ng.bluemix.net/api/v1/web/…/hello1.json @lornajane
Build the Data Pipeline @lornajane
Designing for Serverless • Independent functions • single purpose • testable • distributable @lornajane
Start with Security Need an API key or user creds for bx wsk tool Web actions: we know how to secure HTTP connections, so do it! • Auth standards e.g. JWT • Security in transmission: use HTTPS @lornajane
Logging Considerations • Standard, configurable logging setup • Use a trace_id to link requests between services • Aggregate logs to a central place, ensure search functionality • Collect metrics (invocations, execution time, error rates) • display metrics on a dashboard • have appropriate, configurable alerting @lornajane
Pipeline Actions Sequence socron • collector makes an API call, passes on data • invoker fires many actions: one for each item Sequence qhandler • storer inserts or updates the record • notifier sends a webhook to slack or a bot @lornajane
Pipeline Actions @lornajane
Serverless And Data @lornajane
Resources • Cloud Functions: https://console.bluemix.net/openwhisk/ • Code https://github.com/ibm-watson-data-lab/soingest • My blog: https://lornajane.net/ • OpenWhisk: https://openwhisk.org/ • CouchDB: https://couchdb.apache.org/ • Offline First: https://offlinefirst.org/ @lornajane
