Enable session affinity to handle load accross multiple replicas

Author: chaudhariniraj

infra/avm/main.bicep

@@ -1236,6 +1236,7 @@ module containerApp './modules/compute/container-app.bicep' = {
 module containerAppMcp './modules/compute/container-app.bicep' = {
   name: take('module.container-app-mcp.${solutionName}', 64)
   params: {
+    enableSessionAffinity : enableScalability? true: false
     name: 'ca-mcp-${solutionSuffix}'
     location: location
     tags: tags

infra/avm/main.json

@@ -6,7 +6,7 @@
     "_generator": {
       "name": "bicep",
       "version": "0.44.1.10279",
-      "templateHash": "8714866940320286579"
+      "templateHash": "3428880183705727582"
     },
     "name": "Multi-Agent Custom Automation Engine - AVM",
     "description": "AVM orchestrator for the Multi-Agent Custom Automation Engine accelerator. Deploys the same logical resources and preserves the same outputs as infra\\main.bicep using local AVM wrapper modules."
@@ -51004,7 +51004,7 @@
             "_generator": {
               "name": "bicep",
               "version": "0.44.1.10279",
-              "templateHash": "9906697545075116207"
+              "templateHash": "5778435438637774225"
             }
           },
           "parameters": {
@@ -51142,6 +51142,13 @@
               "metadata": {
                 "description": "Enable Azure telemetry collection."
               }
+            },
+            "enableSessionAffinity": {
+              "type": "bool",
+              "defaultValue": false,
+              "metadata": {
+                "description": "Enable sticky session affinity."
+              }
             }
           },
           "resources": {
@@ -51173,6 +51180,7 @@
                   "containers": {
                     "value": "[parameters('containers')]"
                   },
+                  "stickySessionsAffinity": "[if(parameters('enableSessionAffinity'), createObject('value', 'sticky'), createObject('value', 'none'))]",
                   "ingressExternal": "[if(parameters('disableIngress'), createObject('value', false()), createObject('value', parameters('ingressExternal')))]",
                   "ingressTargetPort": {
                     "value": "[parameters('ingressTargetPort')]"
@@ -52788,6 +52796,7 @@
         },
         "mode": "Incremental",
         "parameters": {
+          "enableSessionAffinity": "[if(parameters('enableScalability'), createObject('value', true()), createObject('value', false()))]",
           "name": {
             "value": "[format('ca-mcp-{0}', variables('solutionSuffix'))]"
           },
@@ -52920,7 +52929,7 @@
             "_generator": {
               "name": "bicep",
               "version": "0.44.1.10279",
-              "templateHash": "9906697545075116207"
+              "templateHash": "5778435438637774225"
             }
           },
           "parameters": {
@@ -53058,6 +53067,13 @@
               "metadata": {
                 "description": "Enable Azure telemetry collection."
               }
+            },
+            "enableSessionAffinity": {
+              "type": "bool",
+              "defaultValue": false,
+              "metadata": {
+                "description": "Enable sticky session affinity."
+              }
             }
           },
           "resources": {
@@ -53089,6 +53105,7 @@
                   "containers": {
                     "value": "[parameters('containers')]"
                   },
+                  "stickySessionsAffinity": "[if(parameters('enableSessionAffinity'), createObject('value', 'sticky'), createObject('value', 'none'))]",
                   "ingressExternal": "[if(parameters('disableIngress'), createObject('value', false()), createObject('value', parameters('ingressExternal')))]",
                   "ingressTargetPort": {
                     "value": "[parameters('ingressTargetPort')]"

infra/avm/modules/compute/container-app.bicep

@@ -62,6 +62,9 @@ param workloadProfileName string?
 @description('Enable Azure telemetry collection.')
 param enableTelemetry bool = true
 
+@description('Enable sticky session affinity.')
+param enableSessionAffinity bool = false
+
 // ============================================================================
 // Container App (AVM)
 // ============================================================================
@@ -74,6 +77,7 @@ module containerApp 'br/public:avm/res/app/container-app:0.22.1' = {
     enableTelemetry: enableTelemetry
     environmentResourceId: environmentResourceId
     containers: containers
+    stickySessionsAffinity: enableSessionAffinity? 'sticky': 'none'
     ingressExternal: disableIngress ? false : ingressExternal
     ingressTargetPort: ingressTargetPort
     ingressTransport: ingressTransport