flagger/docs/README.md

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Flagger	name content keywords gitops kubernetes flagger istio linkerd appmesh name content twitter:card summary_large_image name content twitter:title Flagger name content twitter:description Progressive delivery Kubernetes operator (Canary, A/B Testing and Blue/Green deployments) name content twitter:image:src https://flagger.app/flagger-overview.png	true	Flagger	Progressive Delivery Operator for Kubernetes	Get Started →	https://docs.flagger.app	title details Safer Releases Reduce the risk of introducing a new software version in production by gradually shifting traffic to the new version while measuring metrics like HTTP/gRPC request success rate and latency. title details Flexible Traffic Routing Shift and route traffic between app versions using a service mesh like Istio, Linkerd or AWS App Mesh. If you're not using a service mesh then an ingress controller like NGINX or Gloo can also be used. title details Extensible Validation Besides the builtin metrics checks, the application analysis can be extended with custom Prometheus metrics and webhooks for running acceptance tests, load tests, or any other custom validation.	Apache License 2.0 | Copyright © 2019 Weaveworks

Progressive Delivery

Flagger was designed to give developers confidence in automating production releases with progressive delivery techniques.

::: tip Canary release

A benefit of using canary releases is the ability to do capacity testing of the new version in a production environment with a safe rollback strategy if issues are found. By slowly ramping up the load, you can monitor and capture metrics about how the new version impacts the production environment.

Martin Fowler :::

Flagger can run automated application analysis, testing, promotion and rollback for the following deployment strategies:

• Canary (progressive traffic shifting)
  • Istio, Linkerd, App Mesh, NGINX, Gloo
• A/B Testing (HTTP headers and cookies traffic routing)
  • Istio, NGINX
• Blue/Green (traffic switching)
  • Kubernetes CNI

Flagger can be configures to send notifications to a Slack or Microsoft Teams channel. It will post messages when a deployment has been initialised, when a new revision has been detected and if the canary analysis failed or succeeded.

GitOps

You can build fully automated GitOps pipelines for canary deployments with Flagger and FluxCD (CNCF sandbox project).

::: tip GitOps

GitOps is a way to do Kubernetes cluster management and application delivery. It works by using Git as a single source of truth for declarative infrastructure and applications. With Git at the center of your delivery pipelines, developers can make pull requests to accelerate and simplify application deployments and operations tasks to Kubernetes.

Weaveworks :::

GitOps tutorials:

• Progressive Delivery for Istio with Flagger and Flux
• Progressive Delivery for Linkerd with Flagger and Flux

Getting Help

If you have any questions about Flagger and progressive delivery:

• Read the Flagger docs.
• Invite yourself to the Weave community slack and join the #flagger channel.
• Join the Weave User Group and get invited to online talks, hands-on training and meetups in your area.
• File an issue.

Your feedback is always welcome!