feat: OB-37376 merge cf stacks for push and pull by adding poller rol…

…e to stack

apps/stack/template.yaml

@@ -37,6 +37,11 @@ Metadata:
           default: CloudWatch Metrics
         Parameters:
           - MetricStreamFilterUri
+      - Label:
+          default: Cloudwatch Metrics Poller
+        Parameters:
+          - ObserveAwsAccountId
+          - DatastreamIds
       - Label:
           default: Forwarder Options
         Parameters:
@@ -150,6 +155,18 @@ Parameters:
     Description: >-
       The token used to retrieve metric configuration.
     Default: ''
+  ObserveAwsAccountId:
+    Type: String
+    Description: Observe AWS Account ID which will be allowed to assume role.
+    AllowedPattern: '\d*'
+    Default: ''
+  DatastreamIds:
+    Type: CommaDelimitedList
+    Description: Datastream IDs where data will be ingested to.
+      This ensures Observe cannot assume this role outside
+      of this context.
+    AllowedPattern: \d*
+    Default: ''
   SourceBucketNames:
     Type: CommaDelimitedList
     Description: >-
@@ -214,7 +231,10 @@ Conditions:
     - !Equals
       - !Ref DatasourceID
       - ""
-
+  EnableMetricsPoller: !Not
+    - !Equals
+      - !Ref ObserveAwsAccountId
+      - ""
 Resources:
   Topic:
     Type: "AWS::SNS::Topic"
@@ -378,6 +398,22 @@ Resources:
           - UseStackName
           - !Sub "${AWS::StackName}-MetricStream"
           - !Sub "${NameOverride}-MetricStream"
+  MetricsPoller:
+    Type: AWS::Serverless::Application
+    Condition: EnableMetricsPoller
+    Properties:
+      Location: ../externalrole/template.yaml
+      NotificationARNs:
+        - !Ref Topic
+      Parameters:
+        ObserveAwsAccountId: !Ref ObserveAwsAccountId
+        AllowedActions: >-
+          cloudwatch:GetMetricData,cloudwatch:ListMetrics,tag:GetResources
+        DatastreamIds: !Join [",", !Ref DatastreamIds]
+        NameOverride: !If
+          - UseStackName
+          - !Sub "${AWS::StackName}-MetricsPoller"
+          - !Sub "${NameOverride}-MetricsPoller"
 Outputs:
   BucketName:
     Description: >-