Implement ec2.register_image() (#3177)

* implement register_image

* format code

moto/ec2/models.py

@@ -1516,6 +1516,19 @@ class AmiBackend(object):
 
         return True
 
+    def register_image(self, name=None, description=None):
+        ami_id = random_ami_id()
+        ami = Ami(
+            self,
+            ami_id,
+            instance=None,
+            source_ami=None,
+            name=name,
+            description=description,
+        )
+        self.amis[ami_id] = ami
+        return ami
+
     def remove_launch_permission(self, ami_id, user_ids=None, group=None):
         ami = self.describe_images(ami_ids=[ami_id])[0]
         self.validate_permission_targets(user_ids=user_ids, group=group)

moto/ec2/responses/amis.py

@@ -73,8 +73,12 @@ class AmisResponse(BaseResponse):
             return MODIFY_IMAGE_ATTRIBUTE_RESPONSE
 
     def register_image(self):
+        name = self.querystring.get("Name")[0]
+        description = self._get_param("Description", if_none="")
         if self.is_not_dryrun("RegisterImage"):
-            raise NotImplementedError("AMIs.register_image is not yet implemented")
+            image = self.ec2_backend.register_image(name, description)
+            template = self.response_template(REGISTER_IMAGE_RESPONSE)
+            return template.render(image=image)
 
     def reset_image_attribute(self):
         if self.is_not_dryrun("ResetImageAttribute"):
@@ -190,3 +194,8 @@ MODIFY_IMAGE_ATTRIBUTE_RESPONSE = """
    <return>true</return>
 </ModifyImageAttributeResponse>
 """
+
+REGISTER_IMAGE_RESPONSE = """<RegisterImageResponse xmlns="http://ec2.amazonaws.com/doc/2013-10-15/">
+   <requestId>59dbff89-35bd-4eac-99ed-be587EXAMPLE</requestId>
+   <imageId>{{ image.id }}</imageId>
+</RegisterImageResponse>"""