Successfully reported this slideshow.
We use your LinkedIn profile and activity data to personalize ads and to show you more relevant ads. You can change your ad preferences anytime.

AWS Lambda from the trenches (Serverless London)

507 views

Published on

AWS Lambda has changed the way we deploy and run software, but this new serverless paradigm has created new challenges to old problems - how do you test a cloud-hosted function locally? How do you monitor them? What about logging and config management? And how do we start migrating from existing architectures?

In this talk Yan will discuss solutions to these challenges by drawing from real-world experience running Lambda in production and migrating from an existing monolithic architecture.

Published in: Technology
  • Be the first to comment

AWS Lambda from the trenches (Serverless London)

  1. 1. from the TRENCHESTRENCHES what you should know before you go to production AWS LAMBDAAWS LAMBDA
  2. 2. hi,I’mYanCui
  3. 3. hi,I’mYanCui AWS user since 2009
  4. 4. apr, 2016
  5. 5. hidden complexities and dependencies low utilisation to leave room for traffic spikes EC2 scaling is slow, so scale earlier lots of cost for unused resources up to 30 mins for deployment deployment required downtime
  6. 6. - Dan North “lead time to someone saying thank you is the only reputation metric that matters.”
  7. 7. “what would good look like for us?”
  8. 8. be small be fast have zero downtime have no lock-step DEPLOYMENTS SHOULD...
  9. 9. FEATURES SHOULD... be deployable independently be loosely-coupled
  10. 10. WE WANT TO... minimise cost for unused resources minimise ops effort reduce tech mess deliver visible improvements faster
  11. 11. nov, 2016
  12. 12. 170 Lambda functions in prod 1.2 GB deployment packages in prod 95% cost saving vs EC2 15x no. of prod releases per month
  13. 13. time is a good fit
  14. 14. 1st function in prod! time is a good fit
  15. 15. ? time is a good fit 1st function in prod!
  16. 16. Practices ToolsPrinciples what is good? how to make it good? with what?
  17. 17. Principles outlast Tools
  18. 18. ALERTING CI / CD TESTING LOGGING MONITORING
  19. 19. 170 functions WOOF! ? ? time is a good fit 1st function in prod!
  20. 20. SECURITY DISTRIBUTED TRACING CONFIG MANAGEMENT
  21. 21. evolving the PLATFORM
  22. 22. rebuilt search
  23. 23. Legacy Monolith Amazon Kinesis Amazon Lambda Amazon CloudSearch
  24. 24. Legacy Monolith Amazon Kinesis Amazon Lambda Amazon CloudSearchAmazon API Gateway Amazon Lambda
  25. 25. new analytics pipeline
  26. 26. Legacy Monolith Amazon Kinesis Amazon Lambda Google BigQuery
  27. 27. Legacy Monolith Amazon Kinesis Amazon Lambda Google BigQuery 1 developer, 2 days design production (his 1st serverless project)
  28. 28. Legacy Monolith Amazon Kinesis Amazon Lambda Google BigQuery “nothing ever got done this fast at Skype!” - Chris Twamley
  29. 29. - Dan North “lead time to someone saying thank you is the only reputation metric that matters.”
  30. 30. Rebuilt with Lambda
  31. 31. Rebuilt with Lambda
  32. 32. BigQuery
  33. 33. BigQuery
  34. 34. grapheneDB BigQuery
  35. 35. grapheneDB BigQuery
  36. 36. grapheneDB BigQuery
  37. 37. getting PRODUCTION READY
  38. 38. CHOOSE A FRAMEWORK DEPLOYMENT
  39. 39. http://serverless.com
  40. 40. https://github.com/awslabs/serverless-application-model
  41. 41. http://apex.run
  42. 42. https://apex.github.io/up
  43. 43. https://github.com/claudiajs/claudia
  44. 44. https://github.com/Miserlou/Zappa
  45. 45. http://gosparta.io/
  46. 46. TESTING
  47. 47. amzn.to/29Lxuzu
  48. 48. Level of Testing 1.Unit do our objects do the right thing? are they easy to work with?
  49. 49. Level of Testing 1.Unit 2.Integration does our code work against code we can’t change?
  50. 50. handler
  51. 51. handler test by invoking the handler
  52. 52. Level of Testing 1.Unit 2.Integration 3.Acceptance does the whole system work?
  53. 53. Level of Testing unit integration acceptance feedback confidence
  54. 54. “…We find that tests that mock external libraries often need to be complex to get the code into the right state for the functionality we need to exercise. The mess in such tests is telling us that the design isn’t right but, instead of fixing the problem by improving the code, we have to carry the extra complexity in both code and test…” Don’t Mock Types You Can’t Change
  55. 55. “…The second risk is that we have to be sure that the behaviour we stub or mock matches what the external library will actually do… Even if we get it right once, we have to make sure that the tests remain valid when we upgrade the libraries…” Don’t Mock Types You Can’t Change
  56. 56. Don’t Mock Types You Can’t Change Services
  57. 57. Paul Johnston The serverless approach to testing is different and may actually be easier. http://bit.ly/2t5viwK
  58. 58. LambdaAPI Gateway DynamoDB
  59. 59. LambdaAPI Gateway DynamoDB Unit Tests
  60. 60. LambdaAPI Gateway DynamoDB Unit Tests Mock/Stub
  61. 61. is our request correct? is the request mapping set up correctly?is the API resources configured correctly? are we assuming the correct schema? LambdaAPI Gateway DynamoDB is Lambda proxy configured correctly? is IAM policy set up correctly? is the table created? what unit tests will not tell you…
  62. 62. most Lambda functions are simple have single purpose, the risk of shipping broken software has largely shifted to how they integrate with external services observation
  63. 63. But it slows down my feedback loop… IT’S NOT ABOUT YOU!
  64. 64. IT’S CHINA. NOT SCHINA.
  65. 65. me Your users shouldn’t be the ones to pay the price for your faster feedback loop. Optimise for working software. Test your software end-to-end.
  66. 66. “…Wherever possible, an acceptance test should exercise the system end-to- end without directly calling its internal code. An end-to-end test interacts with the system only from the outside: through its interface…” Testing End-to-End
  67. 67. Legacy Monolith Amazon Kinesis Amazon Lambda Amazon CloudSearchAmazon API Gateway Amazon Lambda
  68. 68. Legacy Monolith Amazon Kinesis Amazon Lambda Amazon CloudSearchAmazon API Gateway Amazon Lambda Test Input
  69. 69. Legacy Monolith Amazon Kinesis Amazon Lambda Amazon CloudSearchAmazon API Gateway Amazon Lambda Test Input Validate
  70. 70. integration tests exercise system’s Integration with its external dependencies
  71. 71. acceptance tests exercise system End-to-End from the outside
  72. 72. integration tests differ from acceptance tests only in HOW the Lambda functions are invoked observation
  73. 73. CI + CD PIPELINE
  74. 74. “the earlier you consider CI + CD, the more time you save in the long run” - me
  75. 75. “…We prefer to have the end-to-end tests exercise both the system and the process by which it’s built and deployed… This sounds like a lot of effort (it is), but has to be done anyway repeatedly during the software’s lifetime…” Testing End-to-End
  76. 76. “deployment scripts that only live on the CI box is a disaster waiting to happen” - me
  77. 77. Jenkins build config deploys and tests unit + integration tests deploy acceptance tests
  78. 78. if [ "$1" = "deploy" ] && [ $# -eq 4 ]; then STAGE=$2 REGION=$3 PROFILE=$4 npm install AWS_PROFILE=$PROFILE 'node_modules/.bin/sls' deploy -s $STAGE -r $REGION elif [ "$1" = "int-test" ] && [ $# -eq 4 ]; then STAGE=$2 REGION=$3 PROFILE=$4 npm install AWS_PROFILE=$PROFILE npm run int-$STAGE elif [ "$1" = "acceptance-test" ] && [ $# -eq 4 ]; then STAGE=$2 REGION=$3 PROFILE=$4 npm install AWS_PROFILE=$PROFILE npm run acceptance-$STAGE else usage exit 1 fi
  79. 79. build.sh allows repeatable builds on both local & CI
  80. 80. Auto Auto Manual
  81. 81. LOGGING
  82. 82. 2016-07-12T12:24:37.571Z 994f18f9-482b-11e6-8668-53e4eab441ae GOT is off air, what do I do now?
  83. 83. 2016-07-12T12:24:37.571Z 994f18f9-482b-11e6-8668-53e4eab441ae GOT is off air, what do I do now? UTC Timestamp API Gateway Request Id your log message
  84. 84. function name date function version
  85. 85. LOG OVERLOAD
  86. 86. CENTRALISE LOGS
  87. 87. CENTRALISE LOGS MAKE THEM EASILY SEARCHABLE
  88. 88. + + the elk stack
  89. 89. CloudWatch Logs
  90. 90. CloudWatch Logs AWS Lambda ELK stack
  91. 91. CloudWatch Events
  92. 92. http://bit.ly/2f3zxQG
  93. 93. DISTRIBUTED TRACING
  94. 94. “my followers didn’t receive my new post!” - a user
  95. 95. where could the problem be?
  96. 96. correlation IDs* * eg. request-id, user-id, yubl-id, etc.
  97. 97. ROLL YOUR OWN CLIENTS
  98. 98. kinesis client http client sns client
  99. 99. http://bit.ly/2k93hAj
  100. 100. ROLL YOUR OWN CLIENTS X-RAY
  101. 101. Amazon X-Ray
  102. 102. Amazon X-Ray
  103. 103. traces do not span over API Gateway
  104. 104. http://bit.ly/2s9yxmA
  105. 105. MONITORING + ALERTING
  106. 106. “where do I install monitoring agents?”
  107. 107. you can’t
  108. 108. • invocation Count • error Count • latency • throttling • granular to the minute • support custom metrics
  109. 109. • same metrics as CW • better dashboard • support custom metrics https://www.datadoghq.com/blog/monitoring-lambda-functions-datadog/
  110. 110. “how do I batch up and send logs in the background?”
  111. 111. you can’t (kinda)
  112. 112. console.log(“hydrating yubls from db…”); console.log(“fetching user info from user-api”); console.log(“MONITORING|1489795335|27.4|latency|user-api-latency”); console.log(“MONITORING|1489795335|8|count|yubls-served”); timestamp metric value metric type metric namemetrics logs
  113. 113. CloudWatch Logs AWS Lambda ELK stack logs metrics CloudWatch
  114. 114. http://bit.ly/2gGredx
  115. 115. DASHBOARDS
  116. 116. DASHBOARDS SET ALARMS
  117. 117. DASHBOARDS SET ALARMS TRACK APP-LEVEL METRICS
  118. 118. Not Only CloudWatch
  119. 119. “you really don't want your monitoring system to fail at the same time as the system it monitors” - me
  120. 120. CONFIG MANAGEMENT
  121. 121. easily and quickly propagate config changes
  122. 122. CENTRALISED CONFIG SERVICE
  123. 123. config service goes here
  124. 124. SSM Parameter Store
  125. 125. sensitive data should be encrypted in-flight, and at rest (credentials, connection string, etc.)
  126. 126. role-based access
  127. 127. SSM Parameter Store HTTPS role-based access encrypted in-flight
  128. 128. SSM Parameter Store encrypt role-based access
  129. 129. SSM Parameter Store encrypted at-rest
  130. 130. HTTPS role-based access SSM Parameter Store encrypted in-flight
  131. 131. CENTRALISED CONFIG SERVICE CLIENT LIBRARY
  132. 132. fetch & cache at Cold Start
  133. 133. invalidate at interval + signal
  134. 134. http://bit.ly/2yLUjwd
  135. 135. PRO TIPS
  136. 136. max 75 GB total deployment package size* * limit is per AWS region
  137. 137. Janitor Monkey
  138. 138. Janitor Lambda http://bit.ly/2xzVu4a
  139. 139. disable versionFunctions in
  140. 140. install Serverless framework as dev dependency at project level dev dependencies are excluded since 1.16.0
  141. 141. http://bit.ly/2vzBqhC
  142. 142. http://amzn.to/2vtUkDU
  143. 143. UNDERSTAND COLDSTARTS
  144. 144. Amazon X-Ray 1st invocation 2nd invocation cold start
  145. 145. source: http://bit.ly/2oBEbw2
  146. 146. EMBRACE NODE.JS & PYTHON
  147. 147. http://bit.ly/2rtCCBz
  148. 148. C# http://bit.ly/2rtCCBz
  149. 149. Java http://bit.ly/2rtCCBz
  150. 150. NodeJs, Python http://bit.ly/2rtCCBz
  151. 151. what about type safety?
  152. 152. complexity ceiling of a Node.js app complexity
  153. 153. complexity ceiling of a Node.js app complexity referential transparency immutability as default type inference option types union types …
  154. 154. for managing complexity complexity ceiling of a Node.js app complexity referential transparency immutability as default type inference option types union types …
  155. 155. complexity ceiling of a Node.js app complexity complexity ceiling of a Node.js Lambda function
  156. 156. if you can limit the complexity of your solution, maybe you won’t need the tools for managing that complexity. me
  157. 157. AVOID HARD ASSUMPTIONS ABOUT FUNCTION LIFETIME
  158. 158. USE STATE FOR OPTIMISATION
  159. 159. AVOID COLDSTARTS
  160. 160. CloudWatch Event AWS Lambda
  161. 161. CloudWatch Event AWS Lambda ping ping ping ping
  162. 162. CloudWatch Event AWS Lambda ping ping ping ping
  163. 163. CloudWatch Event AWS Lambda ping ping ping ping HEALTH CHECKS?
  164. 164. max 5 mins execution time
  165. 165. USE RECURSION FOR LONG RUNNING TASKS
  166. 166. CONSIDER PARTIAL FAILURES
  167. 167. “AWS Lambda polls your stream and invokes your Lambda function. Therefore, if a Lambda function fails, AWS Lambda attempts to process the erring batch of records until the time the data expires…” http://docs.aws.amazon.com/lambda/latest/dg/retries-on-errors.html
  168. 168. should function fail on partial/any failures?
  169. 169. SNS Kinesis SQS after 3 attempts share processing logic events are processed in chronological order failed events are retried out of sequence
  170. 170. PROCESS SQS WITH RECURSIVE FUNCTIONS
  171. 171. http://bit.ly/2npomX6
  172. 172. AVOID HOT KINESS STREAMS
  173. 173. “Each shard can support up to 5 transactions per second for reads, up to a maximum total data read rate of 2 MB per second.” http://docs.aws.amazon.com/streams/latest/dev/service-sizes-and-limits.html
  174. 174. “If your stream has 100 active shards, there will be 100 Lambda functions running concurrently. Then, each Lambda function processes events on a shard in the order that they arrive.” http://docs.aws.amazon.com/lambda/latest/dg/concurrent-executions.html
  175. 175. when no. of processors goes up…
  176. 176. ReadProvisionedThroughputExceeded can have too many Kinesis read operations…
  177. 177. ReadRecords.IteratorAge unpredictable spikes in read ‘latency’…
  178. 178. can kinda workaround…
  179. 179. http://bit.ly/2uv5LsH
  180. 180. clever, but costly
  181. 181. for subsystems that don’t have to be realtime, or are task- based (ie. order doesn’t matter), consider other triggers such as S3 or SNS.me
  182. 182. @theburningmonk theburningmonk.com github.com/theburningmonk
  183. 183. @theburningmonk theburningmonk.com github.com/theburningmonk http://bit.ly/2yQZj1H all my blog posts on Lambda
  184. 184. sign up here: http://bit.ly/2xIO23O

×