Migrate nixops-aws to python3

This does a 1-way migration to python3, and fully resolves #29.

Aside from the `release.nix`, there are no manual changes in this PR. It was
generated with:

    2to3 -n -w nixopsaws/**/*.py -x dict -x print
    black .

We have already fixed the `print` function in a previous PR, as well as all of
the dictionary iterators. `2to3` is not particularly smart about this and will
add a `list()` cast just about everywhere otherwise.

nixopsaws/resources/__init__.py

@@ -1,4 +1,3 @@
-from __future__ import absolute_import
 from . import aws_vpn_connection
 from . import aws_vpn_connection_route
 from . import aws_vpn_gateway

nixopsaws/resources/ebs_volume.py

@@ -2,7 +2,7 @@
 
 # Automatic provisioning of AWS EBS volumes.
 
-from __future__ import absolute_import
+
 import boto.ec2
 import nixops.util
 import nixopsaws.ec2_utils

nixopsaws/resources/ec2_placement_group.py

@@ -110,7 +110,7 @@ def create(self, defn, check, allow_reboot, allow_recreate):
  self.state = self.UP
  self.placement_group_strategy = grp.strategy
  except boto.exception.EC2ResponseError as e:
- if e.error_code == u"InvalidGroup.NotFound":
+ if e.error_code == "InvalidGroup.NotFound":
  self.state = self.Missing
  else:
  raise
@@ -129,7 +129,7 @@ def create(self, defn, check, allow_reboot, allow_recreate):
  except boto.exception.EC2ResponseError as e:
  if (
  self.state != self.UNKNOWN
- or e.error_code != u"InvalidGroup.Duplicate"
+ or e.error_code != "InvalidGroup.Duplicate"
  ):
  raise
 
@@ -146,7 +146,7 @@ def after_activation(self, defn):
  try:
  conn.delete_placement_group(group["name"])
  except boto.exception.EC2ResponseError as e:
- if e.error_code != u"InvalidGroup.NotFound":
+ if e.error_code != "InvalidGroup.NotFound":
  raise
  self.old_placement_groups = []
 

nixopsaws/resources/ec2_rds_dbinstance.py

@@ -184,7 +184,7 @@ def _try_fetch_dbinstance(self, instance_id):
  try:
  dbinstance = self._conn.get_all_dbinstances(instance_id=instance_id)[0]
  except boto.exception.BotoServerError as bse:
- if bse.error_code == u"DBInstanceNotFound":
+ if bse.error_code == "DBInstanceNotFound":
  dbinstance = None
  else:
  raise
@@ -275,7 +275,7 @@ def _to_boto_kwargs(self, attrs):
 
  def _compare_instance_id(self, instance_id):
  # take care when comparing instance ids, as aws lowercases and converts to unicode
- return unicode(self.rds_dbinstance_id).lower() == unicode(instance_id).lower()
+ return str(self.rds_dbinstance_id).lower() == str(instance_id).lower()
 
  def fetch_security_group_resources(self, config):
  security_groups = []

nixopsaws/resources/ec2_security_group.py

@@ -194,7 +194,7 @@ def retry_notfound(f):
  rules.append(new_rule)
  self.security_group_rules = rules
  except boto.exception.EC2ResponseError as e:
- if e.error_code == u"InvalidGroup.NotFound":
+ if e.error_code == "InvalidGroup.NotFound":
  self.state = self.MISSING
  else:
  raise
@@ -228,7 +228,7 @@ def retry_notfound(f):
  except boto.exception.EC2ResponseError as e:
  if (
  self.state != self.UNKNOWN
- or e.error_code != u"InvalidGroup.Duplicate"
+ or e.error_code != "InvalidGroup.Duplicate"
  ):
  raise
  self.state = self.STARTING # ugh
@@ -284,7 +284,7 @@ def retry_notfound(f):
  )
  )
  except boto.exception.EC2ResponseError as e:
- if e.error_code != u"InvalidPermission.Duplicate":
+ if e.error_code != "InvalidPermission.Duplicate":
  raise
 
  if old_rules:
@@ -345,7 +345,7 @@ def after_activation(self, defn):
  try:
  conn.delete_security_group(group["name"])
  except boto.exception.EC2ResponseError as e:
- if e.error_code != u"InvalidGroup.NotFound":
+ if e.error_code != "InvalidGroup.NotFound":
  raise
  self.old_security_groups = []
 
@@ -365,7 +365,7 @@ def destroy(self, wipe=False):
  error_codes=["DependencyViolation"],
  )
  except boto.exception.EC2ResponseError as e:
- if e.error_code != u"InvalidGroup.NotFound":
+ if e.error_code != "InvalidGroup.NotFound":
  raise
 
  self.state = self.MISSING

nixopsaws/resources/elastic_file_system.py

@@ -2,7 +2,7 @@
 
 # AWS Elastic File Systems.
 
-from __future__ import absolute_import
+
 import uuid
 import boto3
 import botocore

nixopsaws/resources/elastic_file_system_mount_target.py

@@ -2,7 +2,7 @@
 
 # AWS Elastic File System mount targets.
 
-from __future__ import absolute_import
+
 import boto3
 import botocore
 import nixops.util

release.nix

@@ -15,7 +15,7 @@ rec {
  build = pkgs.lib.genAttrs [ "x86_64-linux" "i686-linux" "x86_64-darwin" ] (system:
  with import nixpkgs { inherit system; };
 
- python2Packages.buildPythonApplication rec {
+ python3Packages.buildPythonApplication rec {
  pname = "nixops-aws";
  inherit version;
  namePrefix = "";
@@ -26,8 +26,8 @@ rec {
  substituteAllInPlace setup.py
  '';
 
- buildInputs = with python2Packages; [ nose coverage ];
- propagatedBuildInputs = with python2Packages; [ boto boto3 ];
+ buildInputs = with python3Packages; [ nose coverage ];
+ propagatedBuildInputs = with python3Packages; [ boto boto3 ];
 
  # For "nix-build --run-env".
  shellHook = ''