![@AlexPshul
Fan Out - Fan In
15
import azure.durable_functions as df
def orchestrator_function(context: df.DurableOrchestrationContext):
# Get a list of N work items to process in parallel.
work_batch = yield context.call_activity("F1", None)
parallel_tasks = [ context.call_activity("F2", b) for b in work_batch
]
outputs = yield context.task_all(parallel_tasks)
# Aggregate all N outputs and send the result to F3.
total = sum(outputs)
yield context.call_activity("F3", total)
main = df.Orchestrator.create(orchestrator_function)](https://image.slidesharecdn.com/stateinstatelessserverlessfunctions-210617092323/85/State-in-stateless-serverless-functions-15-320.jpg)
State in stateless serverless functions
- 1. @AlexPshul State in Stateless Serverless Functions Alex Pshul Embrace the serverless @AlexPshul [email protected] https://pshul.com https://meetup.com/Code-Digest
- 2. @AlexPshul
- 3. @AlexPshul Agenda Serverless Functions - Recap Pros Cons Functions Demo State in Stateless? Durable Functions Durable Entities Another Demo! 3 Agenda
- 4. @AlexPshul About Me 4 Alex Pshul Architect, Microsoft Azure MVP, Consultant, Lecturer & Tech Freak More than 10 years of hands-on experience More than 30 projects Co-organizer of the Code.Digest Meetup https://www.meetup.com/Code-Digest/ Talk to me about:
- 5. @AlexPshul Serverless Functions Pros. and Cons. 5
- 8. @AlexPshul Flexible Run native on cloud Or in a container Rich out-of-the-box solutions suite Http Message Bus Timer Easy to start Easy to deploy 8
- 9. @AlexPshul But… Latency Constant high load Premium functions (Azure) Provisioned Concurrency (AWS) Resource intensive computing Stateful server requests Long running tasks State 9
- 10. @AlexPshul But… Stateful server requests Long running tasks State 10 OR IS IT?
- 12. @AlexPshul State in Stateless Functions Durable Functions 12
- 13. @AlexPshul What is it? Azure Function Extension Supports in a variety of languages C# JavaScript/TypeScript Python F# PowerShell Uses a storage account for persistency Supports various scenarios 13
- 14. @AlexPshul Function Chaining 14 const df = require("durable-functions"); module.exports = df.orchestrator(function*(context) { try { const x = yield context.df.callActivity("F1"); const y = yield context.df.callActivity("F2", x); const z = yield context.df.callActivity("F3", y); return yield context.df.callActivity("F4", z); } catch (error) { // Error handling or compensation goes here. } });
- 15. @AlexPshul Fan Out - Fan In 15 import azure.durable_functions as df def orchestrator_function(context: df.DurableOrchestrationContext): # Get a list of N work items to process in parallel. work_batch = yield context.call_activity("F1", None) parallel_tasks = [ context.call_activity("F2", b) for b in work_batch ] outputs = yield context.task_all(parallel_tasks) # Aggregate all N outputs and send the result to F3. total = sum(outputs) yield context.call_activity("F3", total) main = df.Orchestrator.create(orchestrator_function)
- 16. @AlexPshul Other Scenarios 16 Async HTTP APIs Monitor Human Interaction
- 17. @AlexPshul Durable Entities 17 Allows to store data “in memory” Backed by Durable functions C# JavaScript/TypeScript Python Uses a storage account for persistency Can be accessed from different functions
- 19. @AlexPshul Summary 19 Serverless Easy Scalable Supported by many languages C# JavaScript/TypeScript Python F# (No durable support) PowerShell (No durable support) State in stateless functions with Durable Functions Functions on steroid