• 원본 링크

What is Dapr?

• Dapr : Distributed Application Runtime

Sidecar

• Dapr API (HTTP/gRPC)

Dapr Components

• State Stores
• Pubsub Brokers
• Bindings & Triggers
• Secret Stores
• Observability
• Configuration

Resiliency

• State Management
• Application Configuration
• Input Binding
• Service Invocation
• Secret Management
• Publish & Subscribe
• Output Binding

Resiliency Configuration YAML

Resiliency as CRD

• In kubernetes Resiliency is defined as a CRD
• Allows for multiple policies to be defined
• Dapr merges all found policies into singl configuration

Resiliency Policies

• Timeouts:
  • Allows for the cancellation of requets after a given duration
• Regries:
  • Allows for the generic retrying of a request or operation
  • Two supported retry types. constant and exponential
  • Can specify erros which are retryable and permanent
• Circuit Breakers:
  • Allows for broken/breaking systems to be cut-off from requests
  • Helps reduce traffic and requests to allow for recovery time

Resiliency Policies - Retries

• Constant Policieis:
  • maxRetries - The maximum number of attempts to make for a request
  • duration - The time in-between retries
• Exponential Policies:
  • maxRetries - The maximum number of attempts to make for a request
  • initialinterval - The starting time between retries
  • randomizationFactor - Jitter used to offset requests
  • multiplier - Growth rate of the retry interval
  • maxInterval - The maximum duration between retries
  • maxElapsedTime - The maximum time spent over all retries

Resiliency Policies - Circuit Breakers

• maxRequets - The maximum number of requets allowed while the breakers is in the half-open state
• interval - The cyclical period that errors are evaluated in, if not specified the evaluation period is continuous
• timeout - the Time in which the circuit breaker will remain open after breaking
• trip - The criteria that errors are evaluated against to trigger state changes

Resiliency Targets

• Can be defined as Applications, Actors, and Components
• A target maps the policies to be used when calling into a system

개인 생각

• 전반적으로 kubecon 이 자기가 만들거나 사용하고 있는 프로그램을 소개할수 밖에 없는 구조 이긴한데, 이건 좀 그냥 그랬다.
• 그냥 아.. 있나보다 싶은 생각?
• 굳이 공부한 거라고는 Policy 마다 저런 요소들을 고민해야한다 정도?
• 실제로 내가 Dapr 을 쓸께아니라면, 그닥 매력적인 강연은 아닌것 같다.