Flow Platform

Flow is RWS WM's development and deployment platform.

Purpose and Goals

The Flow Platform intends to streamline development and operational workflows.

It aims to:

• Provide a robust, simple and scalable environment for building, testing, and deploying applications.
• Provide standard solutions for common operational problems. Said problems include, but are not limited to:
  • Continuous Integration and Deployment
  • Secrets Management
  • Policy Management
  • Observability: monitoring, logging and tracing
  • Certificate and trust management
  • Identity and Access Management (not implemented yet)
  • Alerting (not implemented yet)
  • Self-service PostgreSQL (not implemented yet)
  • API management (not implemented yet)
• Make the deployment and operation of our applications consistent, using a reduced number of technology stacks, so TABers can easily switch between applications.
• Enable multitenancy and separation of concerns.

Target Users

There are two main groups of target users

• Suppliers. They are concerned with the development and testing of the applications. They value ease of use, quick turnaround and independance.
• TABers. They value stabiliity, consistency and predictability.

Core Components

The platform consists of the following core components:

• ArgoCD for the continuous delivery of applications
• Cert Manager for managing certificates
• CNPG operator for deploying and operating PostgresQL databases
• External Secrets Operator for managing secrets. Backed by HashiCorp Vault
• Kube-Fledged to manage a cache of container images on all workers
• Kyverno for managing policies
• NFS Provisioner for providing **read-write many" persistent volumes
• SMB CSI Driver - SMB volume driver
• Observability stack based on Grafana, Prometheus, Loki and Tempo
• Stakater Reloader for reloading of application when their config changes
• Trust Manager for managing trust bundles

Flow Platform deployment pipeline

graph TD
  Node1[Gitlab-CI PRE stage]
  Node1 --> Node2[deploy eso on wm-tooling]
  Node1 --> Node3[deploy trustmanager on wm-tooling]
  Node1 --> Node4[render Flow manifests]
  Node1 --> Node5[render test manifests]
  Node5 --> Node101[Gitlab-CI tooling stage]
  Node4 --> Node101
  Node3 --> Node101
  Node2 --> Node101
  Node101 --> Node102[bootstap]
  Node101 --> Node103[deploy wm-infra external secrets on tooling cluster]
  Node101 --> Node104[deploy Argo CD on tooling cluster]
  Node102 --> Node201[Gitlab-CI cluster stage]
  Node103 --> Node201
  Node104 --> Node201


  Node201 --> Node202[Child pipeline for cluster 'X']
  Node202 --> Node203[Deploy Argo CD agent on cluster 'X']
  Node203 --> Node204[Deploy Flow apps for cluster 'X' to tooling Argo CD]
  Node204 --> Node205[Deploy external secrets to cluster 'X']

  Node201 --> Node302[Child pipeline for cluster 'enabling-test']
  Node302 --> Node303[Deploy Argo CD agent on cluster 'enabling-test']
  Node303 --> Node304[Deploy Flow apps for cluster 'enabling-test' to tooling Argo CD]
  Node304 --> Node305[Deploy Flow tests for cluster 'enabling-test' to tooling Argo CD]
  Node305 --> Node306[Deploy external secrets to cluster 'enabling-test']