Crossplane Composition SaaS Architecture

Crossplane SaaS Architecture

Crossplane Composition SaaS Cloud Native Control Plane Kubernetes XRD Provider Self-Service Platform Multi-Cloud GitOps Reconciliation Tenant Infrastructure

XRD และ Composition

# === Crossplane XRD & Composition ===

# CompositeResourceDefinition (XRD)
# apiVersion: apiextensions.crossplane.io/v1
# kind: CompositeResourceDefinition
# metadata:
#   name: xdatabases.platform.example.com
# spec:
#   group: platform.example.com
#   names:
#     kind: XDatabase
#     plural: xdatabases
#   claimNames:
#     kind: Database
#     plural: databases
#   versions:
#     - name: v1alpha1
#       served: true
#       referenceable: true
#       schema:
#         openAPIV3Schema:
#           type: object
#           properties:
#             spec:
#               type: object
#               properties:
#                 engine:
#                   type: string
#                   enum: [postgres, mysql]
#                 size:
#                   type: string
#                   enum: [small, medium, large]
#                 region:
#                   type: string
#                   default: ap-southeast-1

# Composition — What gets created
# apiVersion: apiextensions.crossplane.io/v1
# kind: Composition
# metadata:
#   name: database-aws
# spec:
#   compositeTypeRef:
#     apiVersion: platform.example.com/v1alpha1
#     kind: XDatabase
#   resources:
#     - name: vpc
#       base:
#         apiVersion: ec2.aws.upbound.io/v1beta1
#         kind: VPC
#         spec:
#           forProvider:
#             cidrBlock: 10.0.0.0/16
#             enableDnsSupport: true
#     - name: subnet-a
#       base:
#         apiVersion: ec2.aws.upbound.io/v1beta1
#         kind: Subnet
#         spec:
#           forProvider:
#             cidrBlock: 10.0.1.0/24
#     - name: rds
#       base:
#         apiVersion: rds.aws.upbound.io/v1beta1
#         kind: Instance
#         spec:
#           forProvider:
#             engine: postgres
#             instanceClass: db.t3.medium
#             allocatedStorage: 20

from dataclasses import dataclass
from typing import List

@dataclass
class CompositionResource:
    name: str
    kind: str
    provider: str
    status: str

resources_per_tenant = [
    CompositionResource("VPC", "ec2.VPC", "AWS", "Ready"),
    CompositionResource("Subnet x2", "ec2.Subnet", "AWS", "Ready"),
    CompositionResource("Security Group", "ec2.SecurityGroup", "AWS", "Ready"),
    CompositionResource("RDS PostgreSQL", "rds.Instance", "AWS", "Ready"),
    CompositionResource("ElastiCache Redis", "elasticache.Cluster", "AWS", "Ready"),
    CompositionResource("S3 Bucket", "s3.Bucket", "AWS", "Ready"),
]

print("=== Resources per Tenant (Composition) ===")
for r in resources_per_tenant:
    print(f"  [{r.status}] {r.name} ({r.kind}) — {r.provider}")

Self-Service Platform

# === Developer Self-Service ===

# Developer creates a simple Claim
# apiVersion: platform.example.com/v1alpha1
# kind: Database
# metadata:
#   name: tenant-acme-db
#   namespace: tenant-acme
# spec:
#   engine: postgres
#   size: medium
#   region: ap-southeast-1

# kubectl apply -f database-claim.yaml
# kubectl get databases -n tenant-acme
# kubectl describe database tenant-acme-db -n tenant-acme

# SaaS Tenant Onboarding Script
# #!/bin/bash
# TENANT=$1
# kubectl create namespace tenant-$TENANT
# cat <

# === Multi-Cloud & GitOps ===

# ArgoCD + Crossplane GitOps
# Git Repo Structure:
# infrastructure/
# ├── base/
# │   ├── xrd-database.yaml
# │   ├── composition-aws.yaml
# │   └── composition-gcp.yaml
# ├── tenants/
# │   ├── acme-corp/
# │   │   ├── database.yaml
# │   │   └── cache.yaml
# │   └── startup-xyz/
# │       ├── database.yaml
# │       └── cache.yaml
# └── providers/
#     ├── provider-aws.yaml
#     └── provider-gcp.yaml

# ArgoCD Application
# apiVersion: argoproj.io/v1alpha1
# kind: Application
# metadata:
#   name: crossplane-tenants
# spec:
#   source:
#     repoURL: https://github.com/org/infrastructure
#     path: tenants
#   destination:
#     server: https://kubernetes.default.svc
#   syncPolicy:
#     automated:
#       prune: true
#       selfHeal: true

platform_metrics = {
    "Total Tenants": "45 active + 12 trial",
    "Cloud Resources": "270 managed resources",
    "Drift Detected (30d)": "3 (auto-corrected)",
    "Avg Provisioning Time": "4.5 minutes",
    "Failed Provisions (30d)": "1 (quota limit)",
    "Multi-region": "3 regions (AP, US, EU)",
    "Monthly Cloud Cost": "$8,500",
    "Total MRR": "52,960 บาท",
}

print("Platform Engineering Dashboard:")
for k, v in platform_metrics.items():
    print(f"  {k}: {v}")

# Composition Selection by Region
compositions = {
    "ap-southeast-1": "composition-aws-ap",
    "us-east-1": "composition-aws-us",
    "eu-west-1": "composition-aws-eu",
    "asia-east1": "composition-gcp-asia",
}

print(f"\n\nComposition by Region:")
for region, comp in compositions.items():
    print(f"  [{region}]: {comp}")