The Sidecar Concept

In this configuration, PvRForecast and SAP-RFC are deployed as Sidecars to PvTaskManager.

Key Characteristics of Your Sidecar Implementation

• Shared Network Stack

By using network_mode: "container:pv_task_manager", the sidecars do not have their own IP addresses.
They share the localhost of the Task Manager.

• Simplified Communication

The Task Manager calls the service using http://localhost:PORT, rather than an external DNS name.

1. R Forecast service via http://localhost:8000
2. SAP-RFC service via http://localhost:9090

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1. Implementation in Azure Kubernetes Service (AKS)

In Kubernetes, the sidecar pattern is native. You group these containers into a single Pod.

All containers within a Pod share:

• the same network namespace (localhost)
• the same storage volumes

AKS Deployment Manifest (YAML)

apiVersion: apps/v1
kind: Deployment
metadata:
  name: pv-task-manager-pod
spec:
  replicas: 1
  selector:
    matchLabels:
      app: task-manager
  template:
    metadata:
      labels:
        app: task-manager
    spec:
      containers:
      # 1. Main Container
      - name: pv-task-manager
        image: planvisage.azurecr.io/pvtaskmanagerscheduler:latest
        env:
        - name: R_FRCST_URL
          value: "http://localhost:8000"
        ports:
        - containerPort: 8081

      # 2. Sidecar: R Forecast
      - name: pv-r-forecast
        image: planvisage.azurecr.io/pvrforecast:latest

      # 3. Sidecar: SAP RFC
      - name: sap-rfc
        image: planvisage.azurecr.io/pv-sap-rfc-api:latest

---

2. Implementation in AWS ECS (Fargate / EC2)

In AWS ECS, the equivalent of a Kubernetes Pod is a Task Definition.

To replicate the Docker Compose Sidecar pattern, you define multiple containers within a single Task.

When using the awsvpc network mode (standard for Fargate), containers in the same task communicate via localhost.

ECS Task Definition (JSON Snippet)

{
  "containerDefinitions": [
    {
      "name": "PvTaskManager",
      "image": "planvisage.azurecr.io/pvtaskmanagerscheduler:latest",
      "portMappings": [
        { "containerPort": 8081, "hostPort": 8081 }
      ],
      "environment": [
        { "name": "R_FRCST_URL", "value": "http://localhost:8000" }
      ]
    },
    {
      "name": "PvRForecast",
      "image": "planvisage.azurecr.io/pvrforecast:latest",
      "dependsOn": [
        { "containerName": "PvTaskManager", "condition": "START" }
      ]
    },
    {
      "name": "SAP-RFC",
      "image": "planvisage.azurecr.io/pv-sap-rfc-api:latest",
      "dependsOn": [
        { "containerName": "PvTaskManager", "condition": "START" }
      ]
    }
  ]
}

---

3. Implementation Using Docker Compose

name: 'planvisage-scm'

services:

  PvWebApplication:
    image: planvisage.azurecr.io/pvwebapp:latest
    hostname: PV-WebApplication
    ports:
      - "8081:8080"
    environment:
      - TZ=Asia/Kolkata
      - LICENSE_KEY=v3vh-t8m2-y1x3-s8t9
      - LICENSE_NAME=planvisage-demo
      - LICENSE_EMAIL=shiyas.m@planvisage.com
      - DB_CONNECTSTR=Data Source=host.docker.internal;Initial Catalog=SUDC_PV;User ID=sa;Password=sa123;TrustServerCertificate=True;
      - TASK_MNGR_URL=http://PvTaskManager:8080
    volumes:
      - ./PvWebApp/log/:/app/wwwroot/log/
      - ./PvWebApp/xml/:/app/wwwroot/xml/
    networks:
      - pv-network

  PvTaskManager:
    image: planvisage.azurecr.io/pvtaskmanagerscheduler:latest
    container_name: pv_task_manager
    ports:
      - "8082:8081"
      - "8083:8000"
      - "8084:9090"
    environment:
      - TZ=Asia/Kolkata
      - DB_CONNECTSTR=Data Source=host.docker.internal;Initial Catalog=SUDC_PV;User ID=sa;Password=sa123;TrustServerCertificate=True;
      - R_FRCST_URL=http://localhost:8000
    volumes:
      - ./PvWebAppTaskMngr/log/:/app/wwwroot/log/
      - ./PvWebAppTaskMngr/xml/:/app/wwwroot/xml/
    networks:
      - pv-network

  PvRForecast:
    image: planvisage.azurecr.io/pvrforecast:latest
    network_mode: "container:pv_task_manager"
    environment:
      - TZ=Asia/Kolkata
    depends_on:
      - PvTaskManager

  SAP-RFC:
    image: planvisage.azurecr.io/pv-sap-rfc-api:latest
    network_mode: "container:pv_task_manager"
    environment:
      - TZ=Asia/Kolkata
    depends_on:
      - PvTaskManager

networks:
  pv-network:
    driver: bridge

---

Summary

Platform	Equivalent Concept	Communication
Docker Compose	Sidecar via network_mode: container	localhost
Kubernetes (AKS)	Multiple containers in a Pod	localhost
AWS ECS	Multiple containers in a Task Definition	localhost

The core idea is the same across platforms:

Containers share the same network namespace, allowing them to communicate using localhost instead of external service DNS.