Merge pull request #2324 from acsbendi/elbv2-stopped-instance-target

ELBv2 DescribeTargetHealth returns correct response for stopped instance

moto/elbv2/models.py

@@ -35,12 +35,13 @@ from .exceptions import (
 
 class FakeHealthStatus(BaseModel):
 
-    def __init__(self, instance_id, port, health_port, status, reason=None):
+    def __init__(self, instance_id, port, health_port, status, reason=None, description=None):
         self.instance_id = instance_id
         self.port = port
         self.health_port = health_port
         self.status = status
         self.reason = reason
+        self.description = description
 
 
 class FakeTargetGroup(BaseModel):
@@ -69,7 +70,7 @@ class FakeTargetGroup(BaseModel):
         self.protocol = protocol
         self.port = port
         self.healthcheck_protocol = healthcheck_protocol or 'HTTP'
-        self.healthcheck_port = healthcheck_port or 'traffic-port'
+        self.healthcheck_port = healthcheck_port or str(self.port)
         self.healthcheck_path = healthcheck_path or '/'
         self.healthcheck_interval_seconds = healthcheck_interval_seconds or 30
         self.healthcheck_timeout_seconds = healthcheck_timeout_seconds or 5
@@ -112,10 +113,14 @@ class FakeTargetGroup(BaseModel):
             raise TooManyTagsError()
         self.tags[key] = value
 
-    def health_for(self, target):
+    def health_for(self, target, ec2_backend):
         t = self.targets.get(target['id'])
         if t is None:
             raise InvalidTargetError()
+        if t['id'].startswith("i-"):  # EC2 instance ID
+            instance = ec2_backend.get_instance_by_id(t['id'])
+            if instance.state == "stopped":
+                return FakeHealthStatus(t['id'], t['port'], self.healthcheck_port, 'unused', 'Target.InvalidState', 'Target is in the stopped state')
         return FakeHealthStatus(t['id'], t['port'], self.healthcheck_port, 'healthy')
 
     @classmethod
@@ -712,7 +717,7 @@ class ELBv2Backend(BaseBackend):
 
         if not targets:
             targets = target_group.targets.values()
-        return [target_group.health_for(target) for target in targets]
+        return [target_group.health_for(target, self.ec2_backend) for target in targets]
 
     def set_rule_priorities(self, rule_priorities):
         # validate

moto/elbv2/responses.py

@@ -1208,6 +1208,12 @@ DESCRIBE_TARGET_HEALTH_TEMPLATE = """<DescribeTargetHealthResponse xmlns="http:/
         <HealthCheckPort>{{ target_health.health_port }}</HealthCheckPort>
         <TargetHealth>
           <State>{{ target_health.status }}</State>
+          {% if target_health.reason %}
+            <Reason>{{ target_health.reason }}</Reason>
+          {% endif %}
+          {% if target_health.description %}
+            <Description>{{ target_health.description }}</Description>
+          {% endif %}
         </TargetHealth>
         <Target>
           <Port>{{ target_health.port }}</Port>

tests/test_elbv2/test_elbv2.py

@@ -667,6 +667,91 @@ def test_register_targets():
     response.get('TargetHealthDescriptions').should.have.length_of(1)
 
 
+@mock_ec2
+@mock_elbv2
+def test_stopped_instance_target():
+    target_group_port = 8080
+
+    conn = boto3.client('elbv2', region_name='us-east-1')
+    ec2 = boto3.resource('ec2', region_name='us-east-1')
+
+    security_group = ec2.create_security_group(
+        GroupName='a-security-group', Description='First One')
+    vpc = ec2.create_vpc(CidrBlock='172.28.7.0/24', InstanceTenancy='default')
+    subnet1 = ec2.create_subnet(
+        VpcId=vpc.id,
+        CidrBlock='172.28.7.192/26',
+        AvailabilityZone='us-east-1a')
+    subnet2 = ec2.create_subnet(
+        VpcId=vpc.id,
+        CidrBlock='172.28.7.0/26',
+        AvailabilityZone='us-east-1b')
+
+    conn.create_load_balancer(
+        Name='my-lb',
+        Subnets=[subnet1.id, subnet2.id],
+        SecurityGroups=[security_group.id],
+        Scheme='internal',
+        Tags=[{'Key': 'key_name', 'Value': 'a_value'}])
+
+    response = conn.create_target_group(
+        Name='a-target',
+        Protocol='HTTP',
+        Port=target_group_port,
+        VpcId=vpc.id,
+        HealthCheckProtocol='HTTP',
+        HealthCheckPath='/',
+        HealthCheckIntervalSeconds=5,
+        HealthCheckTimeoutSeconds=5,
+        HealthyThresholdCount=5,
+        UnhealthyThresholdCount=2,
+        Matcher={'HttpCode': '200'})
+    target_group = response.get('TargetGroups')[0]
+
+    # No targets registered yet
+    response = conn.describe_target_health(
+        TargetGroupArn=target_group.get('TargetGroupArn'))
+    response.get('TargetHealthDescriptions').should.have.length_of(0)
+
+    response = ec2.create_instances(
+        ImageId='ami-1234abcd', MinCount=1, MaxCount=1)
+    instance = response[0]
+
+    target_dict = {
+        'Id': instance.id,
+        'Port': 500
+    }
+
+    response = conn.register_targets(
+        TargetGroupArn=target_group.get('TargetGroupArn'),
+        Targets=[target_dict])
+
+    response = conn.describe_target_health(
+        TargetGroupArn=target_group.get('TargetGroupArn'))
+    response.get('TargetHealthDescriptions').should.have.length_of(1)
+    target_health_description = response.get('TargetHealthDescriptions')[0]
+
+    target_health_description['Target'].should.equal(target_dict)
+    target_health_description['HealthCheckPort'].should.equal(str(target_group_port))
+    target_health_description['TargetHealth'].should.equal({
+        'State': 'healthy'
+    })
+
+    instance.stop()
+
+    response = conn.describe_target_health(
+        TargetGroupArn=target_group.get('TargetGroupArn'))
+    response.get('TargetHealthDescriptions').should.have.length_of(1)
+    target_health_description = response.get('TargetHealthDescriptions')[0]
+    target_health_description['Target'].should.equal(target_dict)
+    target_health_description['HealthCheckPort'].should.equal(str(target_group_port))
+    target_health_description['TargetHealth'].should.equal({
+        'State': 'unused',
+        'Reason': 'Target.InvalidState',
+        'Description': 'Target is in the stopped state'
+    })
+
+
 @mock_ec2
 @mock_elbv2
 def test_target_group_attributes():