From 908468edb6e9151d1607972c325f5e9dd22b6681 Mon Sep 17 00:00:00 2001
From: Matthew Gladney <matthew.gladney@divvycloud.com>
Date: Fri, 24 Apr 2020 14:15:22 -0400
Subject: [PATCH] Support OptInStatus for EC2 describe_region calls

---
 moto/ec2/models.py                              | 17 +++++++++++++----
 .../responses/availability_zones_and_regions.py |  1 +
 .../test_availability_zones_and_regions.py      |  7 +++++++
 3 files changed, 21 insertions(+), 4 deletions(-)

diff --git a/moto/ec2/models.py b/moto/ec2/models.py
index 332c8f030..7a9351209 100644
--- a/moto/ec2/models.py
+++ b/moto/ec2/models.py
@@ -1490,9 +1490,10 @@ class AmiBackend(object):
 
 
 class Region(object):
-    def __init__(self, name, endpoint):
+    def __init__(self, name, endpoint, opt_in_status):
         self.name = name
         self.endpoint = endpoint
+        self.opt_in_status = opt_in_status
 
 
 class Zone(object):
@@ -1503,13 +1504,21 @@ class Zone(object):
 
 
 class RegionsAndZonesBackend(object):
+    regions_not_enabled_by_default = [
+        'ap-east-1',
+        'me-south-1'
+    ]
+
     regions = []
     for region in Session().get_available_regions("ec2"):
-        regions.append(Region(region, "ec2.{}.amazonaws.com".format(region)))
+        if region in regions_not_enabled_by_default:
+            regions.append(Region(region, "ec2.{}.amazonaws.com".format(region), "not-opted-in"))
+        else:
+            regions.append(Region(region, "ec2.{}.amazonaws.com".format(region), "opt-in-not-required"))
     for region in Session().get_available_regions("ec2", partition_name="aws-us-gov"):
-        regions.append(Region(region, "ec2.{}.amazonaws.com".format(region)))
+        regions.append(Region(region, "ec2.{}.amazonaws.com".format(region), "opt-in-not-required"))
     for region in Session().get_available_regions("ec2", partition_name="aws-cn"):
-        regions.append(Region(region, "ec2.{}.amazonaws.com.cn".format(region)))
+        regions.append(Region(region, "ec2.{}.amazonaws.com.cn".format(region), "opt-in-not-required"))
 
     zones = {
         "af-south-1": [
diff --git a/moto/ec2/responses/availability_zones_and_regions.py b/moto/ec2/responses/availability_zones_and_regions.py
index 28cc3a495..61d4eb1ae 100644
--- a/moto/ec2/responses/availability_zones_and_regions.py
+++ b/moto/ec2/responses/availability_zones_and_regions.py
@@ -22,6 +22,7 @@ DESCRIBE_REGIONS_RESPONSE = """<DescribeRegionsResponse xmlns="http://ec2.amazon
           <item>
              <regionName>{{ region.name }}</regionName>
              <regionEndpoint>{{ region.endpoint }}</regionEndpoint>
+             <optInStatus>{{ region.opt_in_status }}</optInStatus>
           </item>
       {% endfor %}
    </regionInfo>
diff --git a/tests/test_ec2/test_availability_zones_and_regions.py b/tests/test_ec2/test_availability_zones_and_regions.py
index bec9459e8..92fb2b657 100644
--- a/tests/test_ec2/test_availability_zones_and_regions.py
+++ b/tests/test_ec2/test_availability_zones_and_regions.py
@@ -40,6 +40,13 @@ def test_boto3_describe_regions():
     resp = ec2.describe_regions(RegionNames=[test_region])
     resp["Regions"].should.have.length_of(1)
     resp["Regions"][0].should.have.key("RegionName").which.should.equal(test_region)
+    resp["Regions"][0].should.have.key("OptInStatus").which.should.equal("opt-in-not-required")
+
+    test_region = "ap-east-1"
+    resp = ec2.describe_regions(RegionNames=[test_region])
+    resp["Regions"].should.have.length_of(1)
+    resp["Regions"][0].should.have.key("RegionName").which.should.equal(test_region)
+    resp["Regions"][0].should.have.key("OptInStatus").which.should.equal("not-opted-in")
 
 
 @mock_ec2