A presentation at Apache EU Roadshow in in Berlin, Germany by Lorna Jane Mitchell
Serverless Microservices Are The New Black Lorna Mitchell, IBM
Serverless FaaS: Functions as a Service write a function (many languages supported) deploy it to the cloud (Lambda, Cloud Functions, etc) only pay while the function is running (charged per GBsec) your platform scales on demand @lornajane
When To Go Serverless To create a small, scalable application (focussed API, microservices) For occasional server needs (contact form on static site) To provide compute power (processing quantities of data) To move heavy lifting off web platform (classic example: PDF generation) @lornajane
FaaS + HTTP = Microservices! @lornajane
Microservices Microservices are: small and modular loosely coupled independently developed and deployed great for building components decentralised ... they are basically small HTTP APIs @lornajane
Microservice Design Points I prefer RESTful-ish APIs Status codes are important Headers are for metadata URLs and verbs together define what happens All endpoints are stateless SSL is required @lornajane
Lorna's Plans Service Keep a list of my travel plans, with locations and dates. Use a serverless platform (IBM Cloud Functions) and PostgreSQL GET /plans list all plans GET /plans/42 show one plan POST /plans create a new plan DELETE /plans/42 delete a plan @lornajane
Lorna's Plans Service @lornajane
Creating the Microservices @lornajane
Creating the Microservices @lornajane
Writing Serverless Functions Small, self-contained units of functionality Run on-demand in response to an event Incoming parameters can include event information parameters set at deploy time connection info for other services @lornajane
Make Plans: the Code 1 const
pgp
=
require ( 'pg-promise' )(); 2 function
main ( params )
{ 3
var
postgres_url
=
params [ '__bx_creds' ][ 'compose-for-postgresql' ][ 'uri' ]; 4
var
base_url
=
params [ '__ow_headers' ][ 'x-forwarded-url' ]; 5
return
new
Promise ( function ( resolve ,
reject )
{ 6
db
=
pgp ( postgres_url ,
[]); 7 8
db . one ( "INSERT INTO plans (location, travel_date) VALUES 9 ($1, $2) RETURNING plan_id" , 10
[ location ,
travel_date ]) 11
. then ( function ( data )
{ 12
var
redirect_to
=
base_url
"/"
data . plan_id ; 13
resolve ({ headers :
{ "Location" :
redirect_to }, 14
statusCode :
303 }) 15
}) @lornajane
Prepare to Deploy: package In OpenWhisk, there are "packages". These let us: group actions together add parameters to a package that will be available to all actions From the deployment script, the line to create plans-api : ibmcloud wsk package update plans-api @lornajane
Prepare to Deploy: services The function needs to connect to the database. We can bind the database to the package to achieve this: ibmcloud wsk service bind compose-for-postgresql plans-api @lornajane
Prepare to Deploy: libraries To include extra libraries, we can: create package.json and run npm install zip up index.js and node_modules into a zip file deploy the zip file, and include runtime instructions cd write-plan zip -rq write-plan.zip index.js node_modules @lornajane
Make Plans: Deploy
We're ready! Push the action to the cloud:
ibmcloud wsk action update --kind nodejs:8 --web raw
plans-api/write-plan write-plan.zip
@lornajane
Make Plans: API Gateway
To have this action repsond to our HTTP request, set up the API
Gateway:
create the API
set up the path, verb and action to link together
ibmcloud wsk api create /plans GET plans-api/get-plans
--response-type http
@lornajane
Creating the Microservices @lornajane
Calling The Endpoint
Quick example with cURL (other clients available):
$ curl -L -H "Content-Type: application/json"
https://service.eu.apiconnect.ibmcloud.com/.../plans
-d '{"location": "Turin", "travel_date": "2018-04-11"}'
{
"plans": [{
"plan_id": 3,
"travel_date": "2018-04-11T00:00:00.000Z",
"location": "Turin"
}]
}
@lornajane
Microservices: Security @lornajane
Security In web console: https://console.bluemix.net/openwhisk/apimanagement @lornajane
Security In web console: https://console.bluemix.net/openwhisk/apimanagement @lornajane
Project Structure Many possible approaches, this is mine: . ├── deploy.sh ├── get-plans │ ├── index.js │ ├── node_modules │ ├── package-lock.json │ └── package.json └── write-plan ├── index.js ├── node_modules ├── package-lock.json └── package.json @lornajane
Deployment Using https://travis-ci.com/ deploy with a script script downloads ibmcloud tool and cloud-functions plugin set an API key as an environment variable then run commands (see deploy.sh in GitHub project) @lornajane
Serverless Microservices @lornajane
Serverless Ideal for working with many small parts Apache OpenWhisk paired with API Gateway: perfect candidate for microservices @lornajane
Microservices Service Oriented Architecture is alive and well microservices expose endpoints they share reusable components specific components guard access to services/datastores each component can be separately developed, tested and deployed @lornajane
Resources Code: https://github.com/lornajane/plans-microservice Apache OpenWhisk: http://openwhisk.apache.org IBM Cloud Functions: https://www.ibm.com/cloud/functions My blog: https://lornajane.net @lornajane
Microservices are a great way to build modern, event-driven applications. Come to this session and find out how serverless technology can serve as a solid basis of a microservice. With scalability baked in and a shallow learning curve for developers, these modern platforms are an excellent fit for all your API needs including microservices. Come and learn how to adapt your existing knowledge to build excellent microservices from Serverless platforms such as Apache OpenWhisk and allied technologies like API Gateway. This session is recommended for developers of all levels.
