From Big Band Web App to Serverless Bebop

(presented at JazzCon.Tech 2018: http://jazzcon.tech)

This talk will take a real-world look at what makes serverless so jazzy. Via a case study from Mapbox, we’ll see how to refactor a hard-to-maintain Node Express app into a collection of Lambda functions, and why we'd want to: lower bills, better code, and happier teams.

1. from Big Band Web App to Serverless Bebop @AnjanaVakil JazzCon.Tech 2018
2. Hello! I’m @AnjanaVakil Recurse Center Non-Graduate Mozilla TechSpeaker & Outreachy Alumna Engineering Learning & Development Lead, Mapbox
3. location data platform for developers maps, search, navigation web, iOS, Android, Unity... @AnjanaVakil JazzCon.Tech 2018
4. @AnjanaVakil JazzCon.Tech 2018
5. we use to ◍ get user stats ◍ monitor/test unpacker uploads ◍ ask yoda who’s on call ◍ see who’s out tmrw ◍ pick a random teammate Place your screenshot here @AnjanaVakil JazzCon.Tech 2018
6. user- limits out unpacker yoda stats Express slack i/o auth our slack-commands app node @AnjanaVakil JazzCon.Tech 2018
7. codebase slack-commands/ ├─ readme.md ├─ cloudformation/ #app & cmd config │ └─ slack-commands.template.js ├─ index.js #express app ├─ commands/ │ ├─ out.js │ ├─ stats.js │ └─ ... └─ test/ ├─ index.test.js ├─ out.test.js ├─ stats.test.js └─ ... @AnjanaVakil JazzCon.Tech 2018
8. All commands in a single app: Downsides Security ◍ Permissions? Secrets? ◍ Least privilege Maintenance ◍ Many different teams involved ◍ Ownership? Support? ◍ Code gumbo Cost ◍ Always running ◍ No per-command breakdown @AnjanaVakil JazzCon.Tech 2018
9. enough about computers let’s talk about jazz @AnjanaVakil JazzCon.Tech 2018
10. “ While swing music tended to feature orchestrated big band arrangements, bebop music highlighted improvisation. @AnjanaVakil JazzCon.Tech 2018 wikipedia
11. Big Band Glenn Miller Orchestra, c. 1940
12. Big Band out unpacker status yoda Express slack i/o auth user- limits @AnjanaVakil JazzCon.Tech 2018
13. “ I kept thinking there's bound to be something else. I could hear it sometimes. I couldn't play it.... I found that by using the higher intervals of a chord as a melody line and backing them with appropriately related changes, I could play the thing I'd been hearing. It came alive. - Charlie Parker @AnjanaVakil JazzCon.Tech 2018 wikipedia
14. Bebop Tommy Potter, Charlie Parker, Max Roach, Miles Davis, & Duke Jordan, NYC c. 1945
15. “ As bebop was not intended for dancing, it enabled the musicians to play at faster tempos. Bebop musicians explored advanced harmonies, complex syncopation, altered chords, extended chords, chord substitutions, asymmetrical phrasing, and intricate melodies. @AnjanaVakil JazzCon.Tech 2018 wikipedia
16. Bebop out unpacker status yoda user-limits @AnjanaVakil JazzCon.Tech 2018
17. “there’s bound to be something else” ◍ Assign a single owner/gatekeeper? ◍ Multiple single-command apps? ◍ Separate commands from router app @AnjanaVakil JazzCon.Tech 2018
18. “serverless” functions to the rescue AWS Lambda @AnjanaVakil JazzCon.Tech 2018
19. what do you mean “serverless” Actual Server You own a computer You put code on it You run it constantly (and you pay constantly) You keep it healthy Cloud Server AWS owns a computer (or 2) You put code on it AWS runs it constantly (and you pay constantly) You tell AWS how to keep it healthy “No” Server AWS owns a computer You put code on it AWS runs it when you ask (and you pay only then) AWS keeps it healthy @AnjanaVakil JazzCon.Tech 2018
20. ◍ Only concern: Input -> Output ◍ No state maintained between calls ◍ Can be side-effecting, though (e.g. API call, database write) ◍ Limited resources & exec time (5m) what do you mean “function” @AnjanaVakil JazzCon.Tech 2018
21. Lose the server if it’s... ◍ small ◍ short-lived ◍ self-contained ◍ needed occasionally to lambda or not to lambda Keep the server if it’s... ◍ heavy ◍ long-running ◍ interdependent ◍ needed constantly @AnjanaVakil JazzCon.Tech 2018
22. HTTP API endpoint AWS load balancer EC2s on ECS JS JS JS old architecture @AnjanaVakil JazzCon.Tech 2018
23. HTTP API endpoint router new architecture stats out unpacker yoda @AnjanaVakil JazzCon.Tech 2018
24. old codebase slack-commands/ ├─ readme.md ├─ cloudformation/ #app & cmd config │ └─ slack-commands.template.js ├─ index.js #express app code ├─ commands/ #cmd code │ ├─ out.js │ ├─ stats.js │ └─ ... └─ test/ #app & cmd tests ├─ index.test.js ├─ out.test.js ├─ stats.test.js └─ ... @AnjanaVakil JazzCon.Tech 2018
25. new codebase slack-commands/ ├─ readme.md ├─ cloudformation/ #app config │ └─ slack-commands.template.js ├─ index.js #express app code ├─ commander.js #invoke lambdas └─ test/ ├─ commander.test.js └─ index.test.js slack-command-{cmd}/ ├ readme.md ├ cloudformation/ #cmd config │ └ slack-command-{cmd}.template.js ├ index.js #cmd code └ test/ └ index.test.js @AnjanaVakil JazzCon.Tech 2018
26. what does a function look like? @AnjanaVakil JazzCon.Tech 2018
27. Place your screenshot here user stats commmand @AnjanaVakil JazzCon.Tech 2018
28. module.exports.command = (event, context, callback) => { const { ApiCoreUrl, MapboxToken } = process.env; const user = event.args[0]; const from = new Date(event.args[1] || (+new Date - 864e5*30)); // 30d const to = new Date(event.args[2] || (+new Date)); if (isNaN(from)||isNaN(to)) return callback(new Error('invalid date')); const requrl = getStatsUrl(user, from, to, ApiCoreUrl, MapboxToken); request(requrl, (err, res, body) => { if (err||res.statusCode !== 200) return callback(err||res.statusCode); try { const data = JSON.parse(body); } catch(err) { return callback(err); } return callback(null, formatStatsMessage(user, data)); }); } @AnjanaVakil JazzCon.Tech 2018
29. module.exports.command = (event, context, callback) => { const { ApiCoreUrl, MapboxToken } = process.env; const user = event.args[0]; const from = new Date(event.args[1] || (+new Date - 864e5*30)); // 30d const to = new Date(event.args[2] || (+new Date)); if (isNaN(from)||isNaN(to)) return callback(new Error('invalid date')); const requrl = getStatsUrl(user, from, to, ApiCoreUrl, MapboxToken); request(requrl, (err, res, body) => { if (err||res.statusCode !== 200) return callback(err||res.statusCode); try { const data = JSON.parse(body); } catch(err) { return callback(err); } return callback(null, formatStatsMessage(user, data)); }); } handler function (we tell Lambda its name) @AnjanaVakil JazzCon.Tech 2018
30. module.exports.command = (event, context, callback) => { const { ApiCoreUrl, MapboxToken } = process.env; const user = event.args[0]; const from = new Date(event.args[1] || (+new Date - 864e5*30)); // 30d const to = new Date(event.args[2] || (+new Date)); if (isNaN(from)||isNaN(to)) return callback(new Error('invalid date')); const requrl = getStatsUrl(user, from, to, ApiCoreUrl, MapboxToken); request(requrl, (err, res, body) => { if (err||res.statusCode !== 200) return callback(err||res.statusCode); try { const data = JSON.parse(body); } catch(err) { return callback(err); } return callback(null, formatStatsMessage(user, data)); }); } execution environment we can configure @AnjanaVakil JazzCon.Tech 2018
31. module.exports.command = (event, context, callback) => { const { ApiCoreUrl, MapboxToken } = process.env; const user = event.args[0]; const from = new Date(event.args[1] || (+new Date - 864e5*30)); // 30d const to = new Date(event.args[2] || (+new Date)); if (isNaN(from)||isNaN(to)) return callback(new Error('invalid date')); const requrl = getStatsUrl(user, from, to, ApiCoreUrl, MapboxToken); request(requrl, (err, res, body) => { if (err||res.statusCode !== 200) return callback(err||res.statusCode); try { const data = JSON.parse(body); } catch(err) { return callback(err); } return callback(null, formatStatsMessage(user, data)); }); } input { args: [ “vakila”, “1/1”, “3/22”] } @AnjanaVakil JazzCon.Tech 2018
32. module.exports.command = (event, context, callback) => { const { ApiCoreUrl, MapboxToken } = process.env; const user = event.args[0]; const from = new Date(event.args[1] || (+new Date - 864e5*30)); // 30d const to = new Date(event.args[2] || (+new Date)); if (isNaN(from)||isNaN(to)) return callback(new Error('invalid date')); const requrl = getStatsUrl(user, from, to, ApiCoreUrl, MapboxToken); request(requrl, (err, res, body) => { if (err||res.statusCode !== 200) return callback(err||res.statusCode); try { const data = JSON.parse(body); } catch(err) { return callback(err); } return callback(null, formatStatsMessage(user, data)); }); } aws runtime info (e.g. time remaining - ignored here) @AnjanaVakil JazzCon.Tech 2018
33. module.exports.command = (event, context, callback) => { const { ApiCoreUrl, MapboxToken } = process.env; const user = event.args[0]; const from = new Date(event.args[1] || (+new Date - 864e5*30)); // 30d const to = new Date(event.args[2] || (+new Date)); if (isNaN(from)||isNaN(to)) return callback(new Error('invalid date')); const requrl = getStatsUrl(user, from, to, ApiCoreUrl, MapboxToken); request(requrl, (err, res, body) => { if (err||res.statusCode !== 200) return callback(err||res.statusCode); try { const data = JSON.parse(body); } catch(err) { return callback(err); } return callback(null, formatStatsMessage(user, data)); }); } “ok, I’m done” function (AWS passes this when executing) error data @AnjanaVakil JazzCon.Tech 2018
34. we wrote a function! yay @AnjanaVakil JazzCon.Tech 2018
35. do we get it up there? how @AnjanaVakil JazzCon.Tech 2018
36. Cloud::Formation templates ◍ JSON template - “just code” ◍ define your AWS stack components ◍ upload -> AWS builds your stack @AnjanaVakil JazzCon.Tech 2018
37. Cloud::Formation templates { "AWSTemplateFormatVersion": "2010-09-09", "Description": "slack-command-stats", "Parameters": { "ApiCoreUrl": {...}, "MapboxToken": {...} "Resources": { "Command": { "Type": "AWS::Lambda::Function", "Properties": {...} }, "CommandRole": { "Type": "AWS::IAM::Role", "Properties": {...} } }, "Outputs": { ... } } @AnjanaVakil JazzCon.Tech 2018
38. Cloud::Formation templates { "AWSTemplateFormatVersion": "2010-09-09", "Description": "slack-command-stats", "Parameters": { "ApiCoreUrl": {...}, "MapboxToken": {...} "Resources": { "Command": { "Type": "AWS::Lambda::Function", "Properties": {...} }, "CommandRole": { "Type": "AWS::IAM::Role", "Properties": {...} } }, "Outputs": { ... } } stack input params @AnjanaVakil JazzCon.Tech 2018
39. Cloud::Formation templates { "AWSTemplateFormatVersion": "2010-09-09", "Description": "slack-command-stats", "Parameters": { "ApiCoreUrl": {...}, "MapboxToken": {...} "Resources": { "Command": { "Type": "AWS::Lambda::Function", "Properties": {...} }, "CommandRole": { "Type": "AWS::IAM::Role", "Properties": {...} } }, "Outputs": { ... } } aws permissions for function @AnjanaVakil JazzCon.Tech 2018
40. Cloud::Formation templates { "AWSTemplateFormatVersion": "2010-09-09", "Description": "slack-command-stats", "Parameters": { "ApiCoreUrl": {...}, "MapboxToken": {...} "Resources": { "Command": { "Type": "AWS::Lambda::Function", "Properties": {...} }, "CommandRole": { "Type": "AWS::IAM::Role", "Properties": {...} } }, "Outputs": { ... } } actual lambda function the good stuff @AnjanaVakil JazzCon.Tech 2018
41. Cloud::Formation templates "Command": { "Type": "AWS::Lambda::Function", "Properties": { "FunctionName": "slack-command-stats-production", "Code": { "S3Bucket": {...}, "S3Key": {...} }, "Handler": "index.command", "Environment": { "Variables": { "ApiCoreUrl": { "Ref": "ApiCoreUrl" }, "MapboxToken": { "Ref": "MapboxToken" } } }, "Role": { "Fn::GetAtt": ["CommandRole","Arn"] }, "Runtime": "nodejs4.3", "MemorySize": 128, "Timeout": 60, "Tags": [ { "Key": "Team", "Value": "EngOps"} ] } } @AnjanaVakil JazzCon.Tech 2018
42. Cloud::Formation templates "Command": { "Type": "AWS::Lambda::Function", "Properties": { "FunctionName": "slack-command-stats-production", "Code": { "S3Bucket": {...}, "S3Key": {...} }, "Handler": "index.command", "Environment": { "Variables": { "ApiCoreUrl": { "Ref": "ApiCoreUrl" }, "MapboxToken": { "Ref": "MapboxToken" } } }, "Role": { "Fn::GetAtt": ["CommandRole","Arn"] }, "Runtime": "nodejs4.3", "MemorySize": 128, "Timeout": 60, "Tags": [ { "Key": "Team", "Value": "EngOps"} ] } } @AnjanaVakil JazzCon.Tech 2018 function name helps find it later
43. Cloud::Formation templates "Command": { "Type": "AWS::Lambda::Function", "Properties": { "FunctionName": "slack-command-stats-production", "Code": { "S3Bucket": {...}, "S3Key": {...} }, "Handler": "index.command", "Environment": { "Variables": { "ApiCoreUrl": { "Ref": "ApiCoreUrl" }, "MapboxToken": { "Ref": "MapboxToken" } } }, "Role": { "Fn::GetAtt": ["CommandRole","Arn"] }, "Runtime": "nodejs4.3", "MemorySize": 128, "Timeout": 60, "Tags": [ { "Key": "Team", "Value": "EngOps"} ] } } @AnjanaVakil JazzCon.Tech 2018 code to run the good stuff
44. Cloud::Formation templates "Command": { "Type": "AWS::Lambda::Function", "Properties": { "FunctionName": "slack-command-stats-production", "Code": { "S3Bucket": {...}, "S3Key": {...} }, "Handler": "index.command", "Environment": { "Variables": { "ApiCoreUrl": { "Ref": "ApiCoreUrl" }, "MapboxToken": { "Ref": "MapboxToken" } } }, "Role": { "Fn::GetAtt": ["CommandRole","Arn"] }, "Runtime": "nodejs4.3", "MemorySize": 128, "Timeout": 60, "Tags": [ { "Key": "Team", "Value": "EngOps"} ] } } @AnjanaVakil JazzCon.Tech 2018 execution environment can pass in params
45. Cloud::Formation templates "Command": { "Type": "AWS::Lambda::Function", "Properties": { "FunctionName": "slack-command-stats-production", "Code": { "S3Bucket": {...}, "S3Key": {...} }, "Handler": "index.command", "Environment": { "Variables": { "ApiCoreUrl": { "Ref": "ApiCoreUrl" }, "MapboxToken": { "Ref": "MapboxToken" } } }, "Role": { "Fn::GetAtt": ["CommandRole","Arn"] }, "Runtime": "nodejs4.3", "MemorySize": 128, "Timeout": 60, "Tags": [ { "Key": "Team", "Value": "EngOps"} ] } } @AnjanaVakil JazzCon.Tech 2018 permissions from earlier
46. Cloud::Formation templates "Command": { "Type": "AWS::Lambda::Function", "Properties": { "FunctionName": "slack-command-stats-production", "Code": { "S3Bucket": {...}, "S3Key": {...} }, "Handler": "index.command", "Environment": { "Variables": { "ApiCoreUrl": { "Ref": "ApiCoreUrl" }, "MapboxToken": { "Ref": "MapboxToken" } } }, "Role": { "Fn::GetAtt": ["CommandRole","Arn"] }, "Runtime": "nodejs4.3", "MemorySize": 128, "Timeout": 60, "Tags": [ { "Key": "Team", "Value": "EngOps"} ] } } @AnjanaVakil JazzCon.Tech 2018 what to run it on totally not a server
47. Cloud::Formation templates "Command": { "Type": "AWS::Lambda::Function", "Properties": { "FunctionName": "slack-command-stats-production", "Code": { "S3Bucket": {...}, "S3Key": {...} }, "Handler": "index.command", "Environment": { "Variables": { "ApiCoreUrl": { "Ref": "ApiCoreUrl" }, "MapboxToken": { "Ref": "MapboxToken" } } }, "Role": { "Fn::GetAtt": ["CommandRole","Arn"] }, "Runtime": "nodejs4.3", "MemorySize": 128, "Timeout": 60, "Tags": [ { "Key": "Team", "Value": "EngOps"} ] } } @AnjanaVakil JazzCon.Tech 2018 arbitrary tags e.g. who owns this?
48. Mapbox open-source AWS helpers github.com/mapbox/ Command-line tools lambda-cfn create & deploy Node Lambda functions cfn-config configure/start/update CFN stacks JS libraries cloudfriend easily assemble CFN templates in JS decrypt-kms-env use secret environment vars @AnjanaVakil JazzCon.Tech 2018
49. we deployed a function! yay @AnjanaVakil JazzCon.Tech 2018
50. do we call it? how @AnjanaVakil JazzCon.Tech 2018
51. testing in the AWS console (manually) @AnjanaVakil JazzCon.Tech 2018
52. in Node with AWS SDK const AWS = require('aws-sdk'); const runCommand = (req, res, next) => { const [commandName, ...args] = = req.slackText; const params = { FunctionName: `slack-command-${commandName}-production`, // our convention Payload: JSON.stringify({ args: args }), // the `event` Lambda receives }; const lambda = new AWS.Lambda({ region: 'us-east-1' }); lambda.invoke(params).promise() .catch((err) => err.message) // pass on error message as response data .then((data) => res.json(formatForSlack(data))); }; @AnjanaVakil JazzCon.Tech 2018
53. why did we do all that? @AnjanaVakil JazzCon.Tech 2018
54. Before (single app) ◍ Many secrets in one stack ◍ Updating your code updates whole stack ◍ No fine-grained cost analysis Refactoring to Lambda: Benefits After (multiple Lambdas) ◍ Each stack only knows its own secrets ◍ Updating your code leaves others untouched ◍ Each stack/fn can be tagged & cost-monitored @AnjanaVakil JazzCon.Tech 2018
55. HTTP API endpoint router next steps stats out unpacker yoda @AnjanaVakil JazzCon.Tech 2018
56. HTTP API endpoint next steps stats out unpacker yoda @AnjanaVakil JazzCon.Tech 2018 router
57. Merci! @AnjanaVakil anjana@mapbox.com ✌ Team Mapbox Young Hahn, Emily McAfee, Kelly Young, Jake Pruitt, Andrew Evans JazzCon.Tech Organizers Images from Wikimedia Template by SlidesCarnival.com