Enhancement/describe network acls (#3003)

* update describe_network_acls and create unit test

* add fail test case

* adjustment after feedback

* fix result test

IMPLEMENTATION_COVERAGE.md

@@ -2738,7 +2738,7 @@
 - [ ] describe_local_gateways
 - [ ] describe_moving_addresses
 - [ ] describe_nat_gateways
-- [ ] describe_network_acls
+- [X] describe_network_acls
 - [ ] describe_network_interface_attribute
 - [ ] describe_network_interface_permissions
 - [X] describe_network_interfaces

moto/ec2/models.py

@@ -4750,23 +4750,7 @@ class NetworkAclBackend(object):
             )
 
     def get_all_network_acls(self, network_acl_ids=None, filters=None):
-        network_acls = self.network_acls.values()
+        self.describe_network_acls(network_acl_ids, filters)
-
-        if network_acl_ids:
-            network_acls = [
-                network_acl
-                for network_acl in network_acls
-                if network_acl.id in network_acl_ids
-            ]
-            if len(network_acls) != len(network_acl_ids):
-                invalid_id = list(
-                    set(network_acl_ids).difference(
-                        set([network_acl.id for network_acl in network_acls])
-                    )
-                )[0]
-                raise InvalidRouteTableIdError(invalid_id)
-
-        return generic_filter(filters, network_acls)
 
     def delete_network_acl(self, network_acl_id):
         deleted = self.network_acls.pop(network_acl_id, None)
@@ -4886,6 +4870,25 @@ class NetworkAclBackend(object):
             self, association_id, subnet_id, acl.id
         )
 
+    def describe_network_acls(self, network_acl_ids=None, filters=None):
+        network_acls = self.network_acls.values()
+
+        if network_acl_ids:
+            network_acls = [
+                network_acl
+                for network_acl in network_acls
+                if network_acl.id in network_acl_ids
+            ]
+            if len(network_acls) != len(network_acl_ids):
+                invalid_id = list(
+                    set(network_acl_ids).difference(
+                        set([network_acl.id for network_acl in network_acls])
+                    )
+                )[0]
+                raise InvalidRouteTableIdError(invalid_id)
+
+        return generic_filter(filters, network_acls)
+
 
 class NetworkAclAssociation(object):
     def __init__(self, ec2_backend, new_association_id, subnet_id, network_acl_id):

moto/ec2/responses/network_acls.py

@@ -83,7 +83,7 @@ class NetworkACLs(BaseResponse):
     def describe_network_acls(self):
         network_acl_ids = self._get_multi_param("NetworkAclId")
         filters = filters_from_querystring(self.querystring)
-        network_acls = self.ec2_backend.get_all_network_acls(network_acl_ids, filters)
+        network_acls = self.ec2_backend.describe_network_acls(network_acl_ids, filters)
         template = self.response_template(DESCRIBE_NETWORK_ACL_RESPONSE)
         return template.render(network_acls=network_acls)
 

tests/test_ec2/test_network_acls.py

@@ -275,3 +275,32 @@ def test_duplicate_network_acl_entry():
             rule_number
         )
     )
+
+
+@mock_ec2
+def test_describe_network_acls():
+    conn = boto3.client("ec2", region_name="us-west-2")
+
+    vpc = conn.create_vpc(CidrBlock="10.0.0.0/16")
+    vpc_id = vpc["Vpc"]["VpcId"]
+
+    network_acl = conn.create_network_acl(VpcId=vpc_id)
+
+    network_acl_id = network_acl["NetworkAcl"]["NetworkAclId"]
+
+    resp = conn.describe_network_acls(NetworkAclIds=[network_acl_id])
+    result = resp["NetworkAcls"]
+
+    result.should.have.length_of(1)
+    result[0]["NetworkAclId"].should.equal(network_acl_id)
+
+    resp2 = conn.describe_network_acls()["NetworkAcls"]
+    resp2.should.have.length_of(3)
+
+    with assert_raises(ClientError) as ex:
+        conn.describe_network_acls(NetworkAclIds=["1"])
+
+    str(ex.exception).should.equal(
+        "An error occurred (InvalidRouteTableID.NotFound) when calling the "
+        "DescribeNetworkAcls operation: The routeTable ID '1' does not exist"
+    )