More and more applications are being developed as cloud-native, distributed, Microservices-based applications due to a simple reason. Microservice architecture offers an overwhelming set of benefits: better scalability, reliability, loose service coupling, and service-independent deployments. As usual, these benefits come with a price tag, e.g., concurrency issues, failure handling, retry policies, state management, and distributed tracing. This price tag leaves you less time to develop and focus on your business logic. The Distributed Application Runtime (Dapr) is an open-source project by Microsoft attempting to tackle these issues once and for all. It is a portable, event-driven runtime for building distributed applications across cloud and edge. Unlike other abstractions, Dapr is language-agnostic and can run on any platform, cloud vendor, or even on-prem. In this session, we'll introduce Dapr and demonstrate how we can use it to build a distributed, cloud-native, microservices application using various programming languages and frameworks, that can run virtually anywhere.

1. Dapr: The Glue to Your Microservices
Moaid Hathot
Software Consultant
moaidh@codevalue.net
@MoaidHathot
https://moaid.codes
http://codevalue.net
https://meetup.com/Code-Digest

2. Microservices
More and more applications are being developed
as distributed applications
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3. Microservices
 Modularity
 Loose service coupling
 Service-independent deployments
 Better scalability
 Better reliability
 Multiple stacks
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4. Microservices – price tag
 Concurrency issues
 Failure handling
 Retry policies
 State management
 Distributed tracing
 Deployment
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5. Microservices – price tag
Less time to develop business logic
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6. Microservices – price tag
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7. About Moaid Hathot
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Moaid Hathot
 Software Consultant & Code Jedi
 Software Craftsmanship advocate
 Clean Coder
 Co-Founder of Code.Digest();
 OzCode Evangelist

8. Microservices – solutions
 Serverless architecture
 Azure Functions & AWS Lambada
 Stateless, event-driven microservices
 Virtual Actor model
 Object-oriented microservices
 E.g Microsoft Orleans
 The cloud takes care of
 Activating, retries, scaling, failure handling
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9. Microservices – solution issues
 Coupled to Stack
 Coupled to cloud providers
 A single application depends on multiple SDKs
 FaaS and Actor integration can be complicated
 FaaS runtimes can be heavy
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10. Dapr
Distributed Application Runtime
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11. Dapr
 Portable, Event-driven runtime for building microservices
 Open Source
 https://github.com/dapr/dapr
 6.8K Github stars
 117 contributors
 28+ new components since launch
 Alpha phase
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12. Dapr
 Supports any platform
 Services knows only HTTP/gRPC
 Can decide to use dedicated SDKs
 Services are not aware of the actual technologies
 Services are not aware of other services
 Everything is configurable via yaml file
 E.g you can switch from Cosmos DB to DynamoDB
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13. Dapr
 Sidecar architecture
 Dapr is isolated via Process or Container from your app
 Two hosting modes
 Self hosting
 Kubernetes
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14. Dapr – self hosting
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15. Dapr – self hosting
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16. Dapr – self hosting
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HTTP/gRPC

17. Dapr – Kubernetes
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HTTP/gRPC

18. Dapr – Kubernetes
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HTTP/gRPC
Container
Container

19. Dapr – Kubernetes
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HTTP/gRPC
Container
Container
Pod

20. Dapr
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21. Dapr – building blocks
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22. Dapr – building blocks
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23. Dapr – building blocks
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24. Dapr – building blocks
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25. Dapr – building blocks
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26. Dapr – building blocks
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27. Dapr – building blocks
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28. Dapr – building blocks
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29. Dapr – Service Invocation
 Every service has an id (name)
 Calling services has to know that id
 HTTP or gRPC
 Takes care of
 Discoverability
 Reliability
 Retries
 Failure handling
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30. Dapr – Service Invocation
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31. Dapr – Service Invocation
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32. Dapr – Service Invocation
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33. Dapr – Service Invocation
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34. Dapr – Service Invocation
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35. Dapr – Service Invocation
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36. Dapr – Service Invocation
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37. Demo
 Run Dapr
 Service Invocation
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38. Dapr – State Management
 The actual store is not known to services
 Support for many platforms, including:
 Redis
 AWS DynamoDB
 Azure Cosmos DB
 MongoDB
 Cassandra
 SQL Server
 More…
 Easy to implement new state store
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39. Dapr – State Management
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40. Dapr – State Management
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41. Dapr – State Management
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42. Dapr – State Management
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43. Dapr – State Management
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44. Dapr – State Management
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45. Dapr - Secrets
 Provides an API for retrieving secrets
 Supports
 Azure KeyVault
 AWS Secret Manager
 GCP Cloud KMS
 GCP Secret Manager
 Kubernetes
 Hashicorp Vault
 More…
 Easy to implement new secret stores
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46. Dapr – Secrets
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47. Demo
 State Management
 Redis
 CosmosDB
 Secret Store
 Azure KeyVault
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48. Dapr – Pub/Sub
 Publish/subscribe pattern
 Used for decoupling services
 Producer send messages to a topic
 Consumers receives messages from a topic
 Dapr APIs provides at-least-once guarantees
 Supports multiple brokers
 Kafka
 RabbitMQ
 Redis Streams
 Azure Event Hubs
 More…
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49. Dapr – Pub/Sub
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50. Dapr – Pub/Sub
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51. Dapr – Pub/Sub
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52. Dapr – Pub/Sub
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53. Dapr – Pub/Sub
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54. Demo
 Pub/Sub
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55. Dapr – Resource Bindings
 Input/Output with cloud resources
 Similar in concepts to Azure Function’s Binding
 Trigger your service or invoke external systems
 Takes care of connections, polling, queuing, etc…
 Benefits
 Focus on Business logic
 Your code is free from SDKs and libraries
 Auto handling for retries & failure recovery
 Switch bindings at run time
 Deploy to different environments without code changes
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56. Dapr – Resource Bindings
 Inputs (partial list)
 Kafka
 RabbitMQ
 AWS Kinesis
 AWS SQS
 GCP Cloud Pub/Sub
 Azure EventHubs
 Azure SignalR Service
 Azure Service Bus Queues
 More…
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57. Dapr – Resource Bindings
 Outputs (partial list)
 Kafka
 RabbitMQ
 AWS Kinesis
 AWS DynamoDB
 GCP Cloud Pub/Sub
 GCP Storage Bucket
 Azure EventHubs
 Azure SignalR Service
 More…
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58. Dapr – Resource Bindings
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59. Dapr – Resource Bindings
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60. Dapr – Resource Bindings
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Cosmos DB
DynamoDB
Event Hubs

61. Demo
 Bindings
 SignalR Binding
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62. Dapr – Observability
 Monitor the Dapr system services
 Including interaction and behaviors
 Integrates with OpenTelemetry
 Supports
 Azure Monitor
 Azure ApplicationInsights
 Elastic Search
 Zipkin
 More…
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63. Dapr – Observability
 Metrics
 Latency, traffic failures, error rate, CPU usage, etc…
 Logs
 Traces, errors, etc…
 Each trace contains hostname, component name and id, more…
 Distributed Tracing
 Debugging and monitoring distributed flows
 W3C tracing
 Health
 Determine health via HTTP endpoint
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64. Dapr - Dashboard
 Web-based UI for Dapr
 View information, logs, etc…
 Support both locally and Kubernetes sidecars
 Can stop running sidecars (Self hosted)
 View sidecars logs
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65. Dapr - Dashboard
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More Info

66. Demo
 Observability
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67. Dapr – Virtual Actors
 The Actor Model
 Self-contained unit of code (actor)
 Actors interacts using via messages
 The runtime manages how, when and where each actor runs
 Dapr implements the Virtual Actors Model
 Takes care of
 Lifetime
 Retries
 Failover
 Concurrency
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68. summary
 Microservices has many benefits
 But also challenges
 Dapr
 Runtime for building microservices
 Any platform, any stack, any environment
 Takes care of a lot of the challenges
 Open Source
 Community
 Demo repo:
 https://github.com/MoaidHathot/Architecture-next-2020-dapr
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69. Q
A
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70. Moaid Hathot
Software Consultant
moaidh@codevalue.net
@MoaidHathot
https://moaid.codes
http://codevalue.net
https://meetup.com/Code-Digest