From 382c6fe05b14b42465b79709e03574ce13f3e46f Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Victor=20Schr=C3=B6der?= <schrodervictor@gmail.com>
Date: Sun, 14 Jun 2015 22:07:39 +0200
Subject: [PATCH 01/26] Adds basic configuration to ec2.ini to support
 ElastiCache Clusters and Nodes

---
 plugins/inventory/ec2.ini | 12 ++++++++++++
 1 file changed, 12 insertions(+)

diff --git a/plugins/inventory/ec2.ini b/plugins/inventory/ec2.ini
index 6583160f0f..a835b01fe7 100644
--- a/plugins/inventory/ec2.ini
+++ b/plugins/inventory/ec2.ini
@@ -47,6 +47,9 @@ route53 = False
 # To exclude RDS instances from the inventory, uncomment and set to False.
 #rds = False
 
+# To exclude ElastiCache instances from the inventory, uncomment and set to False.
+#elasticache = False
+
 # Additionally, you can specify the list of zones to exclude looking up in
 # 'route53_excluded_zones' as a comma-separated list.
 # route53_excluded_zones = samplezone1.com, samplezone2.com
@@ -59,6 +62,12 @@ all_instances = False
 # 'all_rds_instances' to True return all RDS instances regardless of state.
 all_rds_instances = False
 
+# By default, only ElastiCache clusters and nodes in the 'available' state
+# are returned. Set 'all_elasticache_clusters' and/or 'all_elastic_nodes'
+# to True return all ElastiCache clusters and nodes, regardless of state.
+all_elasticache_clusters = False
+all_elasticache_nodes = False
+
 # API calls to EC2 are slow. For this reason, we cache the results of an API
 # call. Set this to the path you want cache files to be written to. Two files
 # will be written to this directory:
@@ -89,6 +98,9 @@ group_by_tag_none = True
 group_by_route53_names = True
 group_by_rds_engine = True
 group_by_rds_parameter_group = True
+group_by_elasticache_engine = True
+group_by_elasticache_cluster = True
+group_by_elasticache_parameter_group = True
 
 # If you only want to include hosts that match a certain regular expression
 # pattern_include = stage-*

From bc80bd36afbf71b7feab71edc5dfcc5004a0e1fb Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Victor=20Schr=C3=B6der?= <schrodervictor@gmail.com>
Date: Sun, 14 Jun 2015 22:12:03 +0200
Subject: [PATCH 02/26] Adds the necessary logic to ec2.py to load ElastiCache
 related configuration

---
 plugins/inventory/ec2.py | 21 +++++++++++++++++++++
 1 file changed, 21 insertions(+)

diff --git a/plugins/inventory/ec2.py b/plugins/inventory/ec2.py
index 16ac93f5ee..c7fa6bdb15 100755
--- a/plugins/inventory/ec2.py
+++ b/plugins/inventory/ec2.py
@@ -121,6 +121,7 @@ from time import time
 import boto
 from boto import ec2
 from boto import rds
+from boto import elasticache
 from boto import route53
 import six
 
@@ -232,6 +233,11 @@ class Ec2Inventory(object):
         if config.has_option('ec2', 'rds'):
             self.rds_enabled = config.getboolean('ec2', 'rds')
 
+        # Include ElastiCache instances?
+        self.elasticache_enabled = True
+        if config.has_option('ec2', 'elasticache'):
+            self.elasticache_enabled = config.getboolean('ec2', 'elasticache')
+
         # Return all EC2 and RDS instances (if RDS is enabled)
         if config.has_option('ec2', 'all_instances'):
             self.all_instances = config.getboolean('ec2', 'all_instances')
@@ -242,6 +248,18 @@ class Ec2Inventory(object):
         else:
             self.all_rds_instances = False
 
+        # Return all ElastiCache clusters? (if ElastiCache is enabled)
+        if config.has_option('ec2', 'all_elasticache_clusters') and self.elasticache_enabled:
+            self.all_elasticache_clusters = config.getboolean('ec2', 'all_elasticache_clusters')
+        else:
+            self.all_elasticache_clusters = False
+
+        # Return all ElastiCache nodes? (if ElastiCache is enabled)
+        if config.has_option('ec2', 'all_elasticache_nodes') and self.elasticache_enabled:
+            self.all_elasticache_nodes = config.getboolean('ec2', 'all_elasticache_nodes')
+        else:
+            self.all_elasticache_nodes = False
+
         # Cache related
         cache_dir = os.path.expanduser(config.get('ec2', 'cache_path'))
         if not os.path.exists(cache_dir):
@@ -272,6 +290,9 @@ class Ec2Inventory(object):
             'group_by_route53_names',
             'group_by_rds_engine',
             'group_by_rds_parameter_group',
+            'group_by_elasticache_engine',
+            'group_by_elasticache_cluster',
+            'group_by_elasticache_parameter_group',
         ]
         for option in group_by_options:
             if config.has_option('ec2', option):

From 50b320615eee3235b5178637ad8793cefe79c7fa Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Victor=20Schr=C3=B6der?= <schrodervictor@gmail.com>
Date: Sun, 14 Jun 2015 22:13:27 +0200
Subject: [PATCH 03/26] Little improvement in the organization of the
 configuration loader method

---
 plugins/inventory/ec2.py | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/plugins/inventory/ec2.py b/plugins/inventory/ec2.py
index c7fa6bdb15..80afee7444 100755
--- a/plugins/inventory/ec2.py
+++ b/plugins/inventory/ec2.py
@@ -238,11 +238,13 @@ class Ec2Inventory(object):
         if config.has_option('ec2', 'elasticache'):
             self.elasticache_enabled = config.getboolean('ec2', 'elasticache')
 
-        # Return all EC2 and RDS instances (if RDS is enabled)
+        # Return all EC2 instances?
         if config.has_option('ec2', 'all_instances'):
             self.all_instances = config.getboolean('ec2', 'all_instances')
         else:
             self.all_instances = False
+
+        # Return all RDS instances? (if RDS is enabled)
         if config.has_option('ec2', 'all_rds_instances') and self.rds_enabled:
             self.all_rds_instances = config.getboolean('ec2', 'all_rds_instances')
         else:

From 06c6db8e6bfc8d3484720aea8cb902fd971f853c Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Victor=20Schr=C3=B6der?= <schrodervictor@gmail.com>
Date: Sun, 14 Jun 2015 22:21:40 +0200
Subject: [PATCH 04/26] Adds get_elasticache_clusters_by_region method to
 perform the API call to AWS (and sadly finds out that Boto support for
 ElastiCache is very outdated...)

---
 plugins/inventory/ec2.py | 36 ++++++++++++++++++++++++++++++++++++
 1 file changed, 36 insertions(+)

diff --git a/plugins/inventory/ec2.py b/plugins/inventory/ec2.py
index 80afee7444..f64f4a9315 100755
--- a/plugins/inventory/ec2.py
+++ b/plugins/inventory/ec2.py
@@ -357,6 +357,8 @@ class Ec2Inventory(object):
             self.get_instances_by_region(region)
             if self.rds_enabled:
                 self.get_rds_instances_by_region(region)
+            if self.elasticache_enabled:
+                self.get_elasticache_clusters_by_region(region)
 
         self.write_to_cache(self.inventory, self.cache_path_cache)
         self.write_to_cache(self.index, self.cache_path_index)
@@ -417,6 +419,40 @@ class Ec2Inventory(object):
                 error = "Looks like AWS RDS is down:\n%s" % e.message
             self.fail_with_error(error)
 
+    def get_elasticache_clusters_by_region(self, region):
+        ''' Makes an AWS API call to the list of ElastiCache clusters in a
+            particular region.'''
+
+        # ElastiCache boto module doesn't provide a get_all_intances method,
+        # that's why we need to call describe directly (it would be called by
+        # the shorthand method anyway...)
+        try:
+            conn = elasticache.connect_to_region(region)
+            if conn:
+                response = conn.describe_cache_clusters()
+
+        except boto.exception.BotoServerError as e:
+            error = e.reason
+
+            if e.error_code == 'AuthFailure':
+                error = self.get_auth_error_message()
+            if not e.reason == "Forbidden":
+                error = "Looks like AWS RDS is down:\n%s" % e.message
+            self.fail_with_error(error)
+
+        try:
+            # Boto also doesn't provide wrapper classes to CacheClusters or
+            # CacheNodes. Because of that wo can't make use of the get_list
+            # method in the AWSQueryConnection. Let's do the work manually
+            clusters = response['DescribeCacheClustersResponse']['DescribeCacheClustersResult']['CacheClusters']
+
+        except KeyError as e:
+            error = "ElastiCache query to AWS failed (unexpected format)."
+            self.fail_with_error(error)
+
+        for cluster in clusters:
+            self.add_elasticache_cluster(cluster, region)
+
     def get_auth_error_message(self):
         ''' create an informative error message if there is an issue authenticating'''
         errors = ["Authentication error retrieving ec2 inventory."]

From 2cd76cf0e3d160e1e8a7b31a35772ab71bdc75ef Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Victor=20Schr=C3=B6der?= <schrodervictor@gmail.com>
Date: Sun, 14 Jun 2015 22:41:05 +0200
Subject: [PATCH 05/26] Creates add_elasticache_cluster method to digest the
 API answer about ElastiCache clusters

---
 plugins/inventory/ec2.py | 88 ++++++++++++++++++++++++++++++++++++++++
 1 file changed, 88 insertions(+)

diff --git a/plugins/inventory/ec2.py b/plugins/inventory/ec2.py
index f64f4a9315..0f61413451 100755
--- a/plugins/inventory/ec2.py
+++ b/plugins/inventory/ec2.py
@@ -688,6 +688,94 @@ class Ec2Inventory(object):
 
         self.inventory["_meta"]["hostvars"][dest] = self.get_host_info_dict_from_instance(instance)
 
+    def add_elasticache_cluster(self, cluster, region):
+        ''' Adds an ElastiCache cluster to the inventory and index, as long as
+        it's nodes are addressable '''
+
+        # Only want available clusters unless all_elasticache_clusters is True
+        if not self.all_elasticache_clusters and cluster['CacheClusterStatus'] != 'available':
+            return
+
+        # Select the best destination address
+        if 'ConfigurationEndpoint' in cluster and cluster['ConfigurationEndpoint']:
+            # Memcached cluster
+            dest = cluster['ConfigurationEndpoint']['Address']
+        else:
+            # Redis sigle node cluster
+            dest = cluster['CacheNodes'][0]['Endpoint']['Address']
+
+        if not dest:
+            # Skip clusters we cannot address (e.g. private VPC subnet)
+            return
+
+        # Add to index
+        self.index[dest] = [region, cluster['CacheClusterId']]
+
+        # Inventory: Group by instance ID (always a group of 1)
+        if self.group_by_instance_id:
+            self.inventory[cluster['CacheClusterId']] = [dest]
+            if self.nested_groups:
+                self.push_group(self.inventory, 'instances', cluster['CacheClusterId'])
+
+        # Inventory: Group by region
+        if self.group_by_region:
+            self.push(self.inventory, region, dest)
+            if self.nested_groups:
+                self.push_group(self.inventory, 'regions', region)
+
+        # Inventory: Group by availability zone
+        if self.group_by_availability_zone:
+            self.push(self.inventory, cluster['PreferredAvailabilityZone'], dest)
+            if self.nested_groups:
+                if self.group_by_region:
+                    self.push_group(self.inventory, region, cluster['PreferredAvailabilityZone'])
+                self.push_group(self.inventory, 'zones', cluster['PreferredAvailabilityZone'])
+
+        # Inventory: Group by node type
+        if self.group_by_instance_type:
+            type_name = self.to_safe('type_' + cluster['CacheNodeType'])
+            self.push(self.inventory, type_name, dest)
+            if self.nested_groups:
+                self.push_group(self.inventory, 'types', type_name)
+
+        # Inventory: Group by VPC
+        # if self.group_by_vpc_id and instance.subnet_group and instance.subnet_group.vpc_id:
+        #     vpc_id_name = self.to_safe('vpc_id_' + instance.subnet_group.vpc_id)
+        #     self.push(self.inventory, vpc_id_name, dest)
+        #     if self.nested_groups:
+        #         self.push_group(self.inventory, 'vpcs', vpc_id_name)
+
+        # Inventory: Group by security group
+        if self.group_by_security_group:
+            if 'SecurityGroups' in cluster:
+                for security_group in cluster['SecurityGroups']:
+                    key = self.to_safe("security_group_" + security_group['SecurityGroupId'])
+                    self.push(self.inventory, key, dest)
+                    if self.nested_groups:
+                        self.push_group(self.inventory, 'security_groups', key)
+
+        # Inventory: Group by engine
+        if self.group_by_elasticache_engine:
+            self.push(self.inventory, self.to_safe("elasticache_" + cluster['Engine']), dest)
+            if self.nested_groups:
+                self.push_group(self.inventory, 'elasticache_engines', self.to_safe(cluster['Engine']))
+
+        # Inventory: Group by parameter group
+        if self.group_by_elasticache_parameter_group:
+            self.push(self.inventory, self.to_safe("elasticache_parameter_group_" + cluster['CacheParameterGroup']['CacheParameterGroupName']), dest)
+            if self.nested_groups:
+                self.push_group(self.inventory, 'elasticache_parameter_groups', self.to_safe(cluster['CacheParameterGroup']['CacheParameterGroupName']))
+
+        # Inventory: Group by replication group
+        if self.group_by_elasticache_replication_group and 'ReplicationGroupId' in cluster and cluster['ReplicationGroupId']:
+            self.push(self.inventory, self.to_safe("elasticache_replication_group_" + cluster['ReplicationGroupId']), dest)
+            if self.nested_groups:
+                self.push_group(self.inventory, 'elasticache_replication_groups', self.to_safe(cluster['ReplicationGroupId']))
+
+        # Global Tag: all ElastiCache clusters
+        self.push(self.inventory, 'elasticache_clusters', cluster['CacheClusterId'])
+
+        self.inventory["_meta"]["hostvars"][dest] = self.get_host_info_dict_from_instance(cluster)
 
     def get_route53_records(self):
         ''' Get and store the map of resource records to domain names that

From c6f2b08a6010d2309f25c3d82bd97dd3794562f6 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Victor=20Schr=C3=B6der?= <schrodervictor@gmail.com>
Date: Sun, 14 Jun 2015 22:57:03 +0200
Subject: [PATCH 06/26] Creates get_host_info_dict_from_describe_dict helper
 method to translate information from a 'describe' call (we don't have
 instance objects in this case)

---
 plugins/inventory/ec2.py | 41 +++++++++++++++++++++++++++++++++++++++-
 1 file changed, 40 insertions(+), 1 deletion(-)

diff --git a/plugins/inventory/ec2.py b/plugins/inventory/ec2.py
index 0f61413451..b2374cc26f 100755
--- a/plugins/inventory/ec2.py
+++ b/plugins/inventory/ec2.py
@@ -775,7 +775,9 @@ class Ec2Inventory(object):
         # Global Tag: all ElastiCache clusters
         self.push(self.inventory, 'elasticache_clusters', cluster['CacheClusterId'])
 
-        self.inventory["_meta"]["hostvars"][dest] = self.get_host_info_dict_from_instance(cluster)
+        host_info = self.get_host_info_dict_from_describe_dict(cluster)
+
+        self.inventory["_meta"]["hostvars"][dest] = host_info
 
     def get_route53_records(self):
         ''' Get and store the map of resource records to domain names that
@@ -870,6 +872,43 @@ class Ec2Inventory(object):
 
         return instance_vars
 
+    def get_host_info_dict_from_describe_dict(self, describe_dict):
+        ''' Parses the dictionary returned by the API call into a flat list
+            of parameters. This method should be used only when 'describe' is
+            used directly because Boto doesn't provide specific classes. '''
+
+        host_info = {}
+        for key in describe_dict:
+            value = describe_dict[key]
+            key = self.to_safe('ec2_' + key)
+
+            # Handle complex types
+            if key == 'ec2_ConfigurationEndpoint' and value:
+                host_info['ec2_configuration_endpoint_address'] = value['Address']
+                host_info['ec2_configuration_endpoint_port'] = value['Port']
+            if key == 'ec2_Endpoint' and value:
+                host_info['ec2_endpoint_address'] = value['Address']
+                host_info['ec2_endpoint_port'] = value['Port']
+            elif key == 'ec2_CacheParameterGroup':
+                host_info['ec2_cache_parameter_group_name'] = value['CacheParameterGroupName']
+                host_info['ec2_cache_parameter_apply_status'] = value['ParameterApplyStatus']
+            elif key == 'ec2_SecurityGroups':
+                sg_ids = []
+                for sg in value:
+                    sg_ids.append(sg['SecurityGroupId'])
+                host_info["ec2_security_group_ids"] = ','.join([str(i) for i in sg_ids])
+            elif type(value) in [int, bool]:
+                host_info[key] = value
+            elif isinstance(value, six.string_types):
+                host_info[key] = value.strip()
+            elif type(value) == type(None):
+                host_info[key] = ''
+
+            else:
+                pass
+
+        return host_info
+
     def get_host_info(self):
         ''' Get variables about a specific host '''
 

From dbb0304ceab81d1364e9fa9609cf994925abf745 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Victor=20Schr=C3=B6der?= <schrodervictor@gmail.com>
Date: Sun, 14 Jun 2015 23:01:13 +0200
Subject: [PATCH 07/26] Adds uncammelize helper method to put the labels in the
 expected output format

---
 plugins/inventory/ec2.py | 13 ++++++++-----
 1 file changed, 8 insertions(+), 5 deletions(-)

diff --git a/plugins/inventory/ec2.py b/plugins/inventory/ec2.py
index b2374cc26f..0352a5e4f4 100755
--- a/plugins/inventory/ec2.py
+++ b/plugins/inventory/ec2.py
@@ -880,19 +880,19 @@ class Ec2Inventory(object):
         host_info = {}
         for key in describe_dict:
             value = describe_dict[key]
-            key = self.to_safe('ec2_' + key)
+            key = self.to_safe('ec2_' + self.uncammelize(key))
 
             # Handle complex types
-            if key == 'ec2_ConfigurationEndpoint' and value:
+            if key == 'ec2_configuration_endpoint' and value:
                 host_info['ec2_configuration_endpoint_address'] = value['Address']
                 host_info['ec2_configuration_endpoint_port'] = value['Port']
-            if key == 'ec2_Endpoint' and value:
+            if key == 'ec2_endpoint' and value:
                 host_info['ec2_endpoint_address'] = value['Address']
                 host_info['ec2_endpoint_port'] = value['Port']
-            elif key == 'ec2_CacheParameterGroup':
+            elif key == 'ec2_cache_parameter_group':
                 host_info['ec2_cache_parameter_group_name'] = value['CacheParameterGroupName']
                 host_info['ec2_cache_parameter_apply_status'] = value['ParameterApplyStatus']
-            elif key == 'ec2_SecurityGroups':
+            elif key == 'ec2_security_groups':
                 sg_ids = []
                 for sg in value:
                     sg_ids.append(sg['SecurityGroupId'])
@@ -972,6 +972,9 @@ class Ec2Inventory(object):
         cache.write(json_data)
         cache.close()
 
+    def uncammelize(self, key):
+        temp = re.sub('(.)([A-Z][a-z]+)', r'\1_\2', key)
+        return re.sub('([a-z0-9])([A-Z])', r'\1_\2', temp).lower()
 
     def to_safe(self, word):
         ''' Converts 'bad' characters in a string to underscores so they can be

From 98a5531966ec4693ddb3f72f50498b7bd611434e Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Victor=20Schr=C3=B6der?= <schrodervictor@gmail.com>
Date: Sun, 14 Jun 2015 23:03:15 +0200
Subject: [PATCH 08/26] Makes the API requests to return nodes' information too

---
 plugins/inventory/ec2.py | 8 +++++---
 1 file changed, 5 insertions(+), 3 deletions(-)

diff --git a/plugins/inventory/ec2.py b/plugins/inventory/ec2.py
index 0352a5e4f4..165e97099d 100755
--- a/plugins/inventory/ec2.py
+++ b/plugins/inventory/ec2.py
@@ -420,8 +420,8 @@ class Ec2Inventory(object):
             self.fail_with_error(error)
 
     def get_elasticache_clusters_by_region(self, region):
-        ''' Makes an AWS API call to the list of ElastiCache clusters in a
-            particular region.'''
+        ''' Makes an AWS API call to the list of ElastiCache clusters (with
+        nodes' info) in a particular region.'''
 
         # ElastiCache boto module doesn't provide a get_all_intances method,
         # that's why we need to call describe directly (it would be called by
@@ -429,7 +429,9 @@ class Ec2Inventory(object):
         try:
             conn = elasticache.connect_to_region(region)
             if conn:
-                response = conn.describe_cache_clusters()
+                # show_cache_node_info = True
+                # because we also want nodes' information
+                response = conn.describe_cache_clusters(None, None, None, True)
 
         except boto.exception.BotoServerError as e:
             error = e.reason

From 2a242a0e1bb72dcbb226a5ef073103a5008f1c48 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Victor=20Schr=C3=B6der?= <schrodervictor@gmail.com>
Date: Sun, 14 Jun 2015 23:08:10 +0200
Subject: [PATCH 09/26] Creates add_elasticache_node method in ec2.py

---
 plugins/inventory/ec2.py | 99 ++++++++++++++++++++++++++++++++++++++++
 1 file changed, 99 insertions(+)

diff --git a/plugins/inventory/ec2.py b/plugins/inventory/ec2.py
index 165e97099d..cec994798c 100755
--- a/plugins/inventory/ec2.py
+++ b/plugins/inventory/ec2.py
@@ -781,6 +781,105 @@ class Ec2Inventory(object):
 
         self.inventory["_meta"]["hostvars"][dest] = host_info
 
+        # Add the nodes
+        for node in cluster['CacheNodes']:
+            self.add_elasticache_node(node, cluster, region)
+
+    def add_elasticache_node(self, node, cluster, region):
+        ''' Adds an ElastiCache node to the inventory and index, as long as
+        it is addressable '''
+
+        # Only want available nodes unless all_elasticache_nodes is True
+        if not self.all_elasticache_nodes and node['CacheNodeStatus'] != 'available':
+            return
+
+        # Select the best destination address
+        dest = node['Endpoint']['Address']
+
+        if not dest:
+            # Skip nodes we cannot address (e.g. private VPC subnet)
+            return
+
+        node_id = self.to_safe(cluster['CacheClusterId'] + '_' + node['CacheNodeId'])
+
+        # Add to index
+        self.index[dest] = [region, node_id]
+
+        # Inventory: Group by node ID (always a group of 1)
+        if self.group_by_instance_id:
+            self.inventory[node_id] = [dest]
+            if self.nested_groups:
+                self.push_group(self.inventory, 'instances', node_id)
+
+        # Inventory: Group by region
+        if self.group_by_region:
+            self.push(self.inventory, region, dest)
+            if self.nested_groups:
+                self.push_group(self.inventory, 'regions', region)
+
+        # Inventory: Group by availability zone
+        if self.group_by_availability_zone:
+            self.push(self.inventory, cluster['PreferredAvailabilityZone'], dest)
+            if self.nested_groups:
+                if self.group_by_region:
+                    self.push_group(self.inventory, region, cluster['PreferredAvailabilityZone'])
+                self.push_group(self.inventory, 'zones', cluster['PreferredAvailabilityZone'])
+
+        # Inventory: Group by node type
+        if self.group_by_instance_type:
+            type_name = self.to_safe('type_' + cluster['CacheNodeType'])
+            self.push(self.inventory, type_name, dest)
+            if self.nested_groups:
+                self.push_group(self.inventory, 'types', type_name)
+
+        # Inventory: Group by VPC
+        # if self.group_by_vpc_id and instance.subnet_group and instance.subnet_group.vpc_id:
+        #     vpc_id_name = self.to_safe('vpc_id_' + instance.subnet_group.vpc_id)
+        #     self.push(self.inventory, vpc_id_name, dest)
+        #     if self.nested_groups:
+        #         self.push_group(self.inventory, 'vpcs', vpc_id_name)
+
+        # Inventory: Group by security group
+        if self.group_by_security_group:
+            if 'SecurityGroups' in cluster:
+                for security_group in cluster['SecurityGroups']:
+                    key = self.to_safe("security_group_" + security_group['SecurityGroupId'])
+                    self.push(self.inventory, key, dest)
+                    if self.nested_groups:
+                        self.push_group(self.inventory, 'security_groups', key)
+
+        # Inventory: Group by engine
+        if self.group_by_elasticache_engine:
+            self.push(self.inventory, self.to_safe("elasticache_" + cluster['Engine']), dest)
+            if self.nested_groups:
+                self.push_group(self.inventory, 'elasticache_engines', self.to_safe("elasticache_" + cluster['Engine']))
+
+        # Inventory: Group by parameter group
+        # if self.group_by_elasticache_parameter_group:
+        #     self.push(self.inventory, self.to_safe("elasticache_parameter_group_" + cluster['CacheParameterGroup']['CacheParameterGroupName']), dest)
+        #     if self.nested_groups:
+        #         self.push_group(self.inventory, 'elasticache_parameter_groups', self.to_safe("elasticache_parameter_group_" + cluster['CacheParameterGroup']['CacheParameterGroupName']))
+
+        # Inventory: Group by replication group
+        # if self.group_by_elasticache_replication_group and 'ReplicationGroupId' in cluster and cluster['ReplicationGroupId']:
+        #     self.push(self.inventory, self.to_safe("elasticache_replication_group_" + cluster['ReplicationGroupId']), dest)
+        #     if self.nested_groups:
+        #         self.push_group(self.inventory, 'elasticache_replication_groups', self.to_safe("elasticache_" + cluster['ReplicationGroupId']))
+
+        # Inventory: Group by ElastiCache Cluster
+        if self.group_by_elasticache_cluster:
+            self.push(self.inventory, self.to_safe("elasticache_cluster_" + cluster['CacheClusterId']), dest)
+
+        # Global Tag: all ElastiCache nodes
+        self.push(self.inventory, 'elasticache_nodes', dest)
+
+        host_info = self.get_host_info_dict_from_describe_dict(node)
+
+        if dest in self.inventory["_meta"]["hostvars"]:
+            self.inventory["_meta"]["hostvars"][dest].update(host_info)
+        else:
+            self.inventory["_meta"]["hostvars"][dest] = host_info
+
     def get_route53_records(self):
         ''' Get and store the map of resource records to domain names that
         point to them. '''

From e64daba8e72deee8b97d06ed2a3076ed32a607ed Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Victor=20Schr=C3=B6der?= <schrodervictor@gmail.com>
Date: Sun, 14 Jun 2015 23:10:33 +0200
Subject: [PATCH 10/26] Adds a flag (is_redis) to prevent duplicity of
 information about Redis single node clusters

---
 plugins/inventory/ec2.py | 14 +++++++++-----
 1 file changed, 9 insertions(+), 5 deletions(-)

diff --git a/plugins/inventory/ec2.py b/plugins/inventory/ec2.py
index cec994798c..3dddbc65b2 100755
--- a/plugins/inventory/ec2.py
+++ b/plugins/inventory/ec2.py
@@ -702,9 +702,13 @@ class Ec2Inventory(object):
         if 'ConfigurationEndpoint' in cluster and cluster['ConfigurationEndpoint']:
             # Memcached cluster
             dest = cluster['ConfigurationEndpoint']['Address']
+            is_redis = False
         else:
             # Redis sigle node cluster
+            # Because all Redis clusters are single nodes, we'll merge the
+            # info from the cluster with info about the node
             dest = cluster['CacheNodes'][0]['Endpoint']['Address']
+            is_redis = True
 
         if not dest:
             # Skip clusters we cannot address (e.g. private VPC subnet)
@@ -720,13 +724,13 @@ class Ec2Inventory(object):
                 self.push_group(self.inventory, 'instances', cluster['CacheClusterId'])
 
         # Inventory: Group by region
-        if self.group_by_region:
+        if self.group_by_region and not is_redis:
             self.push(self.inventory, region, dest)
             if self.nested_groups:
                 self.push_group(self.inventory, 'regions', region)
 
         # Inventory: Group by availability zone
-        if self.group_by_availability_zone:
+        if self.group_by_availability_zone and not is_redis:
             self.push(self.inventory, cluster['PreferredAvailabilityZone'], dest)
             if self.nested_groups:
                 if self.group_by_region:
@@ -734,7 +738,7 @@ class Ec2Inventory(object):
                 self.push_group(self.inventory, 'zones', cluster['PreferredAvailabilityZone'])
 
         # Inventory: Group by node type
-        if self.group_by_instance_type:
+        if self.group_by_instance_type and not is_redis:
             type_name = self.to_safe('type_' + cluster['CacheNodeType'])
             self.push(self.inventory, type_name, dest)
             if self.nested_groups:
@@ -748,7 +752,7 @@ class Ec2Inventory(object):
         #         self.push_group(self.inventory, 'vpcs', vpc_id_name)
 
         # Inventory: Group by security group
-        if self.group_by_security_group:
+        if self.group_by_security_group and not is_redis:
             if 'SecurityGroups' in cluster:
                 for security_group in cluster['SecurityGroups']:
                     key = self.to_safe("security_group_" + security_group['SecurityGroupId'])
@@ -757,7 +761,7 @@ class Ec2Inventory(object):
                         self.push_group(self.inventory, 'security_groups', key)
 
         # Inventory: Group by engine
-        if self.group_by_elasticache_engine:
+        if self.group_by_elasticache_engine and not is_redis:
             self.push(self.inventory, self.to_safe("elasticache_" + cluster['Engine']), dest)
             if self.nested_groups:
                 self.push_group(self.inventory, 'elasticache_engines', self.to_safe(cluster['Engine']))

From 22020ac3cdf7586273ec362771227f616185b07c Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Victor=20Schr=C3=B6der?= <schrodervictor@gmail.com>
Date: Sun, 14 Jun 2015 23:12:52 +0200
Subject: [PATCH 11/26] Adds the necessary config entries to ec2.ini, to
 support ElastiCache replication groups

---
 plugins/inventory/ec2.ini | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/plugins/inventory/ec2.ini b/plugins/inventory/ec2.ini
index a835b01fe7..b6818e876c 100644
--- a/plugins/inventory/ec2.ini
+++ b/plugins/inventory/ec2.ini
@@ -65,6 +65,7 @@ all_rds_instances = False
 # By default, only ElastiCache clusters and nodes in the 'available' state
 # are returned. Set 'all_elasticache_clusters' and/or 'all_elastic_nodes'
 # to True return all ElastiCache clusters and nodes, regardless of state.
+all_elasticache_replication_groups = False
 all_elasticache_clusters = False
 all_elasticache_nodes = False
 
@@ -101,6 +102,7 @@ group_by_rds_parameter_group = True
 group_by_elasticache_engine = True
 group_by_elasticache_cluster = True
 group_by_elasticache_parameter_group = True
+group_by_elasticache_replication_group = True
 
 # If you only want to include hosts that match a certain regular expression
 # pattern_include = stage-*

From 40ce0727470cf820999dc1591d76e964e57bbdd1 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Victor=20Schr=C3=B6der?= <schrodervictor@gmail.com>
Date: Sun, 14 Jun 2015 23:14:00 +0200
Subject: [PATCH 12/26] Adds the logic to process the new config entries about
 ElastiCache replication groups

---
 plugins/inventory/ec2.py | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/plugins/inventory/ec2.py b/plugins/inventory/ec2.py
index 3dddbc65b2..5004a704d9 100755
--- a/plugins/inventory/ec2.py
+++ b/plugins/inventory/ec2.py
@@ -250,6 +250,12 @@ class Ec2Inventory(object):
         else:
             self.all_rds_instances = False
 
+        # Return all ElastiCache replication groups? (if ElastiCache is enabled)
+        if config.has_option('ec2', 'all_elasticache_replication_groups') and self.elasticache_enabled:
+            self.all_elasticache_replication_groups = config.getboolean('ec2', 'all_elasticache_replication_groups')
+        else:
+            self.all_elasticache_replication_groups = False
+
         # Return all ElastiCache clusters? (if ElastiCache is enabled)
         if config.has_option('ec2', 'all_elasticache_clusters') and self.elasticache_enabled:
             self.all_elasticache_clusters = config.getboolean('ec2', 'all_elasticache_clusters')
@@ -295,6 +301,7 @@ class Ec2Inventory(object):
             'group_by_elasticache_engine',
             'group_by_elasticache_cluster',
             'group_by_elasticache_parameter_group',
+            'group_by_elasticache_replication_group',
         ]
         for option in group_by_options:
             if config.has_option('ec2', option):

From c18f6cae11960735e9be6db0984c35df002abf9f Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Victor=20Schr=C3=B6der?= <schrodervictor@gmail.com>
Date: Sun, 14 Jun 2015 23:15:33 +0200
Subject: [PATCH 13/26] Creates get_elasticache_replication_groups_by_region
 method to handle the API call

---
 plugins/inventory/ec2.py | 35 +++++++++++++++++++++++++++++++++++
 1 file changed, 35 insertions(+)

diff --git a/plugins/inventory/ec2.py b/plugins/inventory/ec2.py
index 5004a704d9..5f80c47675 100755
--- a/plugins/inventory/ec2.py
+++ b/plugins/inventory/ec2.py
@@ -366,6 +366,7 @@ class Ec2Inventory(object):
                 self.get_rds_instances_by_region(region)
             if self.elasticache_enabled:
                 self.get_elasticache_clusters_by_region(region)
+                self.get_elasticache_replication_groups_by_region(region)
 
         self.write_to_cache(self.inventory, self.cache_path_cache)
         self.write_to_cache(self.index, self.cache_path_index)
@@ -462,6 +463,40 @@ class Ec2Inventory(object):
         for cluster in clusters:
             self.add_elasticache_cluster(cluster, region)
 
+    def get_elasticache_replication_groups_by_region(self, region):
+        ''' Makes an AWS API call to the list of ElastiCache replication groups
+        in a particular region.'''
+
+        # ElastiCache boto module doesn't provide a get_all_intances method,
+        # that's why we need to call describe directly (it would be called by
+        # the shorthand method anyway...)
+        try:
+            conn = elasticache.connect_to_region(region)
+            if conn:
+                response = conn.describe_replication_groups()
+
+        except boto.exception.BotoServerError as e:
+            error = e.reason
+
+            if e.error_code == 'AuthFailure':
+                error = self.get_auth_error_message()
+            if not e.reason == "Forbidden":
+                error = "Looks like AWS RDS is down:\n%s" % e.message
+            self.fail_with_error(error)
+
+        try:
+            # Boto also doesn't provide wrapper classes to ReplicationGroups
+            # Because of that wo can't make use of the get_list method in the
+            # AWSQueryConnection. Let's do the work manually
+            replication_groups = response['DescribeReplicationGroupsResponse']['DescribeReplicationGroupsResult']['ReplicationGroups']
+
+        except KeyError as e:
+            error = "ElastiCache query to AWS failed (unexpected format)."
+            self.fail_with_error(error)
+
+        for replication_group in replication_groups:
+            self.add_elasticache_replication_group(replication_group, region)
+
     def get_auth_error_message(self):
         ''' create an informative error message if there is an issue authenticating'''
         errors = ["Authentication error retrieving ec2 inventory."]

From 069ee116995bdab33302287fcf5bce9034c7d893 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Victor=20Schr=C3=B6der?= <schrodervictor@gmail.com>
Date: Sun, 14 Jun 2015 23:18:21 +0200
Subject: [PATCH 14/26] Creates add_elasticache_replication_group method in
 ec2.py dynamic inventory script

---
 plugins/inventory/ec2.py | 52 ++++++++++++++++++++++++++++++++++++++++
 1 file changed, 52 insertions(+)

diff --git a/plugins/inventory/ec2.py b/plugins/inventory/ec2.py
index 5f80c47675..078e07b97b 100755
--- a/plugins/inventory/ec2.py
+++ b/plugins/inventory/ec2.py
@@ -926,6 +926,58 @@ class Ec2Inventory(object):
         else:
             self.inventory["_meta"]["hostvars"][dest] = host_info
 
+    def add_elasticache_replication_group(self, replication_group, region):
+        ''' Adds an ElastiCache replication group to the inventory and index '''
+
+        # Only want available clusters unless all_elasticache_replication_groups is True
+        if not self.all_elasticache_replication_groups and replication_group['Status'] != 'available':
+            return
+
+        # Select the best destination address (PrimaryEndpoint)
+        dest = replication_group['NodeGroups'][0]['PrimaryEndpoint']['Address']
+
+        if not dest:
+            # Skip clusters we cannot address (e.g. private VPC subnet)
+            return
+
+        # Add to index
+        self.index[dest] = [region, replication_group['ReplicationGroupId']]
+
+        # Inventory: Group by ID (always a group of 1)
+        if self.group_by_instance_id:
+            self.inventory[replication_group['ReplicationGroupId']] = [dest]
+            if self.nested_groups:
+                self.push_group(self.inventory, 'instances', replication_group['ReplicationGroupId'])
+
+        # Inventory: Group by region
+        if self.group_by_region:
+            self.push(self.inventory, region, dest)
+            if self.nested_groups:
+                self.push_group(self.inventory, 'regions', region)
+
+        # Inventory: Group by availability zone (doesn't apply to replication groups)
+
+        # Inventory: Group by node type (doesn't apply to replication groups)
+
+        # Inventory: Group by VPC (information not available in the current
+        # AWS API version for replication groups
+
+        # Inventory: Group by security group (doesn't apply to replication groups)
+        # Check this value in cluster level
+
+        # Inventory: Group by engine (replication groups are always Redis)
+        if self.group_by_elasticache_engine:
+            self.push(self.inventory, 'elasticache_redis', dest)
+            if self.nested_groups:
+                self.push_group(self.inventory, 'elasticache_engines', 'redis')
+
+        # Global Tag: all ElastiCache clusters
+        self.push(self.inventory, 'elasticache_replication_groups', replication_group['ReplicationGroupId'])
+
+        host_info = self.get_host_info_dict_from_describe_dict(replication_group)
+
+        self.inventory["_meta"]["hostvars"][dest] = host_info
+
     def get_route53_records(self):
         ''' Get and store the map of resource records to domain names that
         point to them. '''

From f25ad9dc51db9d906174dd7c0e7c1a8905845952 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Victor=20Schr=C3=B6der?= <schrodervictor@gmail.com>
Date: Sun, 14 Jun 2015 23:21:33 +0200
Subject: [PATCH 15/26] Adds the appropriate key checks for ElastiCache
 replication groups in get_dict_from_describe_dict method

---
 plugins/inventory/ec2.py | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/plugins/inventory/ec2.py b/plugins/inventory/ec2.py
index 078e07b97b..9aec945472 100755
--- a/plugins/inventory/ec2.py
+++ b/plugins/inventory/ec2.py
@@ -1088,6 +1088,11 @@ class Ec2Inventory(object):
             if key == 'ec2_endpoint' and value:
                 host_info['ec2_endpoint_address'] = value['Address']
                 host_info['ec2_endpoint_port'] = value['Port']
+            if key == 'ec2_node_groups' and value:
+                host_info['ec2_endpoint_address'] = value[0]['PrimaryEndpoint']['Address']
+                host_info['ec2_endpoint_port'] = value[0]['PrimaryEndpoint']['Port']
+            if key == 'ec2_member_clusters' and value:
+                host_info['ec2_member_clusters'] = ','.join([str(i) for i in value])
             elif key == 'ec2_cache_parameter_group':
                 host_info['ec2_cache_parameter_group_name'] = value['CacheParameterGroupName']
                 host_info['ec2_cache_parameter_apply_status'] = value['ParameterApplyStatus']

From ffd74049da595a2d12b081a9b4c4e039a233da8b Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Victor=20Schr=C3=B6der?= <schrodervictor@gmail.com>
Date: Sun, 14 Jun 2015 23:24:51 +0200
Subject: [PATCH 16/26] Comments about the naming pattern in the script, that
 certainly deserves future refactoring

---
 plugins/inventory/ec2.py | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/plugins/inventory/ec2.py b/plugins/inventory/ec2.py
index 9aec945472..4b205c0d95 100755
--- a/plugins/inventory/ec2.py
+++ b/plugins/inventory/ec2.py
@@ -1076,6 +1076,11 @@ class Ec2Inventory(object):
             of parameters. This method should be used only when 'describe' is
             used directly because Boto doesn't provide specific classes. '''
 
+        # I really don't agree with prefixing everything with 'ec2'
+        # because EC2, RDS and ElastiCache are different services.
+        # I'm just following the pattern used until now to not break any
+        # compatibility.
+
         host_info = {}
         for key in describe_dict:
             value = describe_dict[key]

From 43f9a653d0c6edf0a6c69587ef76f094e7fa1e90 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Victor=20Schr=C3=B6der?= <schrodervictor@gmail.com>
Date: Sun, 14 Jun 2015 23:27:16 +0200
Subject: [PATCH 17/26] Process CacheNodeIdsToReboot complex type for cache
 clusters

---
 plugins/inventory/ec2.py | 1 +
 1 file changed, 1 insertion(+)

diff --git a/plugins/inventory/ec2.py b/plugins/inventory/ec2.py
index 4b205c0d95..4bdde428ce 100755
--- a/plugins/inventory/ec2.py
+++ b/plugins/inventory/ec2.py
@@ -1099,6 +1099,7 @@ class Ec2Inventory(object):
             if key == 'ec2_member_clusters' and value:
                 host_info['ec2_member_clusters'] = ','.join([str(i) for i in value])
             elif key == 'ec2_cache_parameter_group':
+                host_info["ec2_cache_node_ids_to_reboot"] = ','.join([str(i) for i in value['CacheNodeIdsToReboot']])
                 host_info['ec2_cache_parameter_group_name'] = value['CacheParameterGroupName']
                 host_info['ec2_cache_parameter_apply_status'] = value['ParameterApplyStatus']
             elif key == 'ec2_security_groups':

From e692a18a2990505b37aede4c6e814141ec110e34 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Victor=20Schr=C3=B6der?= <schrodervictor@gmail.com>
Date: Sun, 14 Jun 2015 23:29:05 +0200
Subject: [PATCH 18/26] Process information about primary clusters for
 ElastiCache replication groups

---
 plugins/inventory/ec2.py | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/plugins/inventory/ec2.py b/plugins/inventory/ec2.py
index 4bdde428ce..dddcf587af 100755
--- a/plugins/inventory/ec2.py
+++ b/plugins/inventory/ec2.py
@@ -1096,6 +1096,11 @@ class Ec2Inventory(object):
             if key == 'ec2_node_groups' and value:
                 host_info['ec2_endpoint_address'] = value[0]['PrimaryEndpoint']['Address']
                 host_info['ec2_endpoint_port'] = value[0]['PrimaryEndpoint']['Port']
+                for node in value[0]['NodeGroupMembers']:
+                    if node['CurrentRole'] == 'primary':
+                        host_info['ec2_primary_cluster_address'] = node['ReadEndpoint']['Address']
+                        host_info['ec2_primary_cluster_port'] = node['ReadEndpoint']['Port']
+                        host_info['ec2_primary_cluster_id'] = node['CacheClusterId']
             if key == 'ec2_member_clusters' and value:
                 host_info['ec2_member_clusters'] = ','.join([str(i) for i in value])
             elif key == 'ec2_cache_parameter_group':

From 41b034a5d2d2178e93ae5667a65028ad48307367 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Victor=20Schr=C3=B6der?= <schrodervictor@gmail.com>
Date: Sun, 14 Jun 2015 23:29:55 +0200
Subject: [PATCH 19/26] Process information about replica clusters for
 ElastiCache replication groups

---
 plugins/inventory/ec2.py | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/plugins/inventory/ec2.py b/plugins/inventory/ec2.py
index dddcf587af..76fc83497d 100755
--- a/plugins/inventory/ec2.py
+++ b/plugins/inventory/ec2.py
@@ -1096,11 +1096,17 @@ class Ec2Inventory(object):
             if key == 'ec2_node_groups' and value:
                 host_info['ec2_endpoint_address'] = value[0]['PrimaryEndpoint']['Address']
                 host_info['ec2_endpoint_port'] = value[0]['PrimaryEndpoint']['Port']
+                replica_count = 0
                 for node in value[0]['NodeGroupMembers']:
                     if node['CurrentRole'] == 'primary':
                         host_info['ec2_primary_cluster_address'] = node['ReadEndpoint']['Address']
                         host_info['ec2_primary_cluster_port'] = node['ReadEndpoint']['Port']
                         host_info['ec2_primary_cluster_id'] = node['CacheClusterId']
+                    elif node['CurrentRole'] == 'replica':
+                        host_info['ec2_replica_cluster_address_'+ str(replica_count)] = node['ReadEndpoint']['Address']
+                        host_info['ec2_replica_cluster_port_'+ str(replica_count)] = node['ReadEndpoint']['Port']
+                        host_info['ec2_replica_cluster_id_'+ str(replica_count)] = node['CacheClusterId']
+                        replica_count += 1
             if key == 'ec2_member_clusters' and value:
                 host_info['ec2_member_clusters'] = ','.join([str(i) for i in value])
             elif key == 'ec2_cache_parameter_group':

From 77a2ad0e8cc5b6d09a39d21a926060df1976edb3 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Victor=20Schr=C3=B6der?= <schrodervictor@gmail.com>
Date: Sun, 14 Jun 2015 23:32:10 +0200
Subject: [PATCH 20/26] Improves code organization in
 get_dict_from_describe_dict method

---
 plugins/inventory/ec2.py | 22 ++++++++++++++++++++++
 1 file changed, 22 insertions(+)

diff --git a/plugins/inventory/ec2.py b/plugins/inventory/ec2.py
index 76fc83497d..9cb7219f66 100755
--- a/plugins/inventory/ec2.py
+++ b/plugins/inventory/ec2.py
@@ -1087,12 +1087,18 @@ class Ec2Inventory(object):
             key = self.to_safe('ec2_' + self.uncammelize(key))
 
             # Handle complex types
+
+            # Target: Memcached Cache Clusters
             if key == 'ec2_configuration_endpoint' and value:
                 host_info['ec2_configuration_endpoint_address'] = value['Address']
                 host_info['ec2_configuration_endpoint_port'] = value['Port']
+
+            # Target: Cache Nodes and Redis Cache Clusters (single node)
             if key == 'ec2_endpoint' and value:
                 host_info['ec2_endpoint_address'] = value['Address']
                 host_info['ec2_endpoint_port'] = value['Port']
+
+            # Target: Redis Replication Groups
             if key == 'ec2_node_groups' and value:
                 host_info['ec2_endpoint_address'] = value[0]['PrimaryEndpoint']['Address']
                 host_info['ec2_endpoint_port'] = value[0]['PrimaryEndpoint']['Port']
@@ -1107,25 +1113,41 @@ class Ec2Inventory(object):
                         host_info['ec2_replica_cluster_port_'+ str(replica_count)] = node['ReadEndpoint']['Port']
                         host_info['ec2_replica_cluster_id_'+ str(replica_count)] = node['CacheClusterId']
                         replica_count += 1
+
+            # Target: Redis Replication Groups
             if key == 'ec2_member_clusters' and value:
                 host_info['ec2_member_clusters'] = ','.join([str(i) for i in value])
+
+            # Target: All Cache Clusters
             elif key == 'ec2_cache_parameter_group':
                 host_info["ec2_cache_node_ids_to_reboot"] = ','.join([str(i) for i in value['CacheNodeIdsToReboot']])
                 host_info['ec2_cache_parameter_group_name'] = value['CacheParameterGroupName']
                 host_info['ec2_cache_parameter_apply_status'] = value['ParameterApplyStatus']
+
+            # Target: Almost everything
             elif key == 'ec2_security_groups':
                 sg_ids = []
                 for sg in value:
                     sg_ids.append(sg['SecurityGroupId'])
                 host_info["ec2_security_group_ids"] = ','.join([str(i) for i in sg_ids])
+
+            # Target: Everything
+            # Preserve booleans and integers
             elif type(value) in [int, bool]:
                 host_info[key] = value
+
+            # Target: Everything
+            # Sanitize string values
             elif isinstance(value, six.string_types):
                 host_info[key] = value.strip()
+
+            # Target: Everything
+            # Replace None by an empty string
             elif type(value) == type(None):
                 host_info[key] = ''
 
             else:
+                # Remove non-processed complex types
                 pass
 
         return host_info

From e8c3e3d64520f12d3afb224f6fc5e2723535873c Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Victor=20Schr=C3=B6der?= <schrodervictor@gmail.com>
Date: Sun, 14 Jun 2015 23:38:09 +0200
Subject: [PATCH 21/26] Cleans some unnecessary white spaces in ec2.py dynamic
 inventory plugin

---
 plugins/inventory/ec2.py | 6 ++----
 1 file changed, 2 insertions(+), 4 deletions(-)

diff --git a/plugins/inventory/ec2.py b/plugins/inventory/ec2.py
index 9cb7219f66..2c6066fc6a 100755
--- a/plugins/inventory/ec2.py
+++ b/plugins/inventory/ec2.py
@@ -420,7 +420,7 @@ class Ec2Inventory(object):
                     self.add_rds_instance(instance, region)
         except boto.exception.BotoServerError as e:
             error = e.reason
-            
+
             if e.error_code == 'AuthFailure':
                 error = self.get_auth_error_message()
             if not e.reason == "Forbidden":
@@ -513,7 +513,7 @@ class Ec2Inventory(object):
             errors.append(" - No Boto config found at any expected location '%s'" % ', '.join(boto_paths))
 
         return '\n'.join(errors)
-        
+
     def fail_with_error(self, err_msg):
         '''log an error to std err for ansible-playbook to consume and exit'''
         sys.stderr.write(err_msg)
@@ -1025,7 +1025,6 @@ class Ec2Inventory(object):
 
         return list(name_list)
 
-
     def get_host_info_dict_from_instance(self, instance):
         instance_vars = {}
         for key in vars(instance):
@@ -1225,7 +1224,6 @@ class Ec2Inventory(object):
 
         return re.sub("[^A-Za-z0-9\_]", "_", word)
 
-
     def json_format_dict(self, data, pretty=False):
         ''' Converts a dict to a JSON object and dumps it as a formatted
         string '''

From f2d22c1373fe80b19a18a0e91eec7e892a4788da Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Victor=20Schr=C3=B6der?= <schrodervictor@gmail.com>
Date: Mon, 15 Jun 2015 10:02:54 +0200
Subject: [PATCH 22/26] Fixes error messages to mention ElastiCache

---
 plugins/inventory/ec2.py | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/plugins/inventory/ec2.py b/plugins/inventory/ec2.py
index 2c6066fc6a..3f0b950986 100755
--- a/plugins/inventory/ec2.py
+++ b/plugins/inventory/ec2.py
@@ -447,7 +447,7 @@ class Ec2Inventory(object):
             if e.error_code == 'AuthFailure':
                 error = self.get_auth_error_message()
             if not e.reason == "Forbidden":
-                error = "Looks like AWS RDS is down:\n%s" % e.message
+                error = "Looks like AWS ElastiCache is down:\n%s" % e.message
             self.fail_with_error(error)
 
         try:
@@ -481,7 +481,7 @@ class Ec2Inventory(object):
             if e.error_code == 'AuthFailure':
                 error = self.get_auth_error_message()
             if not e.reason == "Forbidden":
-                error = "Looks like AWS RDS is down:\n%s" % e.message
+                error = "Looks like AWS ElastiCache [Replication Groups] is down:\n%s" % e.message
             self.fail_with_error(error)
 
         try:
@@ -491,7 +491,7 @@ class Ec2Inventory(object):
             replication_groups = response['DescribeReplicationGroupsResponse']['DescribeReplicationGroupsResult']['ReplicationGroups']
 
         except KeyError as e:
-            error = "ElastiCache query to AWS failed (unexpected format)."
+            error = "ElastiCache [Replication Groups] query to AWS failed (unexpected format)."
             self.fail_with_error(error)
 
         for replication_group in replication_groups:

From 2acfbce64de08a623598443547e090e7ca987e3a Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Victor=20Schr=C3=B6der?= <schrodervictor@gmail.com>
Date: Mon, 15 Jun 2015 11:35:25 +0200
Subject: [PATCH 23/26] Removes unnecessary commented code and replaces with
 useful information

---
 plugins/inventory/ec2.py | 28 ++++++----------------------
 1 file changed, 6 insertions(+), 22 deletions(-)

diff --git a/plugins/inventory/ec2.py b/plugins/inventory/ec2.py
index 3f0b950986..e07efac4c0 100755
--- a/plugins/inventory/ec2.py
+++ b/plugins/inventory/ec2.py
@@ -786,12 +786,8 @@ class Ec2Inventory(object):
             if self.nested_groups:
                 self.push_group(self.inventory, 'types', type_name)
 
-        # Inventory: Group by VPC
-        # if self.group_by_vpc_id and instance.subnet_group and instance.subnet_group.vpc_id:
-        #     vpc_id_name = self.to_safe('vpc_id_' + instance.subnet_group.vpc_id)
-        #     self.push(self.inventory, vpc_id_name, dest)
-        #     if self.nested_groups:
-        #         self.push_group(self.inventory, 'vpcs', vpc_id_name)
+        # Inventory: Group by VPC (information not available in the current
+        # AWS API version for ElastiCache)
 
         # Inventory: Group by security group
         if self.group_by_security_group and not is_redis:
@@ -878,12 +874,8 @@ class Ec2Inventory(object):
             if self.nested_groups:
                 self.push_group(self.inventory, 'types', type_name)
 
-        # Inventory: Group by VPC
-        # if self.group_by_vpc_id and instance.subnet_group and instance.subnet_group.vpc_id:
-        #     vpc_id_name = self.to_safe('vpc_id_' + instance.subnet_group.vpc_id)
-        #     self.push(self.inventory, vpc_id_name, dest)
-        #     if self.nested_groups:
-        #         self.push_group(self.inventory, 'vpcs', vpc_id_name)
+        # Inventory: Group by VPC (information not available in the current
+        # AWS API version for ElastiCache)
 
         # Inventory: Group by security group
         if self.group_by_security_group:
@@ -900,17 +892,9 @@ class Ec2Inventory(object):
             if self.nested_groups:
                 self.push_group(self.inventory, 'elasticache_engines', self.to_safe("elasticache_" + cluster['Engine']))
 
-        # Inventory: Group by parameter group
-        # if self.group_by_elasticache_parameter_group:
-        #     self.push(self.inventory, self.to_safe("elasticache_parameter_group_" + cluster['CacheParameterGroup']['CacheParameterGroupName']), dest)
-        #     if self.nested_groups:
-        #         self.push_group(self.inventory, 'elasticache_parameter_groups', self.to_safe("elasticache_parameter_group_" + cluster['CacheParameterGroup']['CacheParameterGroupName']))
+        # Inventory: Group by parameter group (done at cluster level)
 
-        # Inventory: Group by replication group
-        # if self.group_by_elasticache_replication_group and 'ReplicationGroupId' in cluster and cluster['ReplicationGroupId']:
-        #     self.push(self.inventory, self.to_safe("elasticache_replication_group_" + cluster['ReplicationGroupId']), dest)
-        #     if self.nested_groups:
-        #         self.push_group(self.inventory, 'elasticache_replication_groups', self.to_safe("elasticache_" + cluster['ReplicationGroupId']))
+        # Inventory: Group by replication group (done at cluster level)
 
         # Inventory: Group by ElastiCache Cluster
         if self.group_by_elasticache_cluster:

From d164c9c7a0f0c2c2c2db6edf3092b41f0beccaa7 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Victor=20Schr=C3=B6der?= <schrodervictor@gmail.com>
Date: Mon, 15 Jun 2015 11:36:33 +0200
Subject: [PATCH 24/26] Adds explanation about all_elasticache_nodes and
 all_elastic_clusters settings

---
 plugins/inventory/ec2.ini | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/plugins/inventory/ec2.ini b/plugins/inventory/ec2.ini
index b6818e876c..c21e512c0d 100644
--- a/plugins/inventory/ec2.ini
+++ b/plugins/inventory/ec2.ini
@@ -65,6 +65,11 @@ all_rds_instances = False
 # By default, only ElastiCache clusters and nodes in the 'available' state
 # are returned. Set 'all_elasticache_clusters' and/or 'all_elastic_nodes'
 # to True return all ElastiCache clusters and nodes, regardless of state.
+#
+# Note that all_elasticache_nodes only applies to listed clusters. That means
+# if you set all_elastic_clusters to false, no node will be return from
+# unavailable clusters, regardless of the state and to what you set for
+# all_elasticache_nodes.
 all_elasticache_replication_groups = False
 all_elasticache_clusters = False
 all_elasticache_nodes = False

From d88a42570e459d962c33ceb92466f64075fdc808 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Victor=20Schr=C3=B6der?= <schrodervictor@gmail.com>
Date: Mon, 29 Jun 2015 21:56:36 +0200
Subject: [PATCH 25/26] Adds a check for 'not None' values when iterating
 ElastiCache SecurityGroups keys

---
 plugins/inventory/ec2.py | 12 ++++++++++--
 1 file changed, 10 insertions(+), 2 deletions(-)

diff --git a/plugins/inventory/ec2.py b/plugins/inventory/ec2.py
index e07efac4c0..081990cd8f 100755
--- a/plugins/inventory/ec2.py
+++ b/plugins/inventory/ec2.py
@@ -791,7 +791,11 @@ class Ec2Inventory(object):
 
         # Inventory: Group by security group
         if self.group_by_security_group and not is_redis:
-            if 'SecurityGroups' in cluster:
+
+            # Check for the existance of the 'SecurityGroups' key and also if
+            # this key has some value. When the cluster is not placed in a SG
+            # the query can return None here and cause an error.
+            if 'SecurityGroups' in cluster and cluster['SecurityGroups'] is not None:
                 for security_group in cluster['SecurityGroups']:
                     key = self.to_safe("security_group_" + security_group['SecurityGroupId'])
                     self.push(self.inventory, key, dest)
@@ -879,7 +883,11 @@ class Ec2Inventory(object):
 
         # Inventory: Group by security group
         if self.group_by_security_group:
-            if 'SecurityGroups' in cluster:
+
+            # Check for the existance of the 'SecurityGroups' key and also if
+            # this key has some value. When the cluster is not placed in a SG
+            # the query can return None here and cause an error.
+            if 'SecurityGroups' in cluster and cluster['SecurityGroups'] is not None:
                 for security_group in cluster['SecurityGroups']:
                     key = self.to_safe("security_group_" + security_group['SecurityGroupId'])
                     self.push(self.inventory, key, dest)

From df77d087a52cd7ab004ef1d1b9be6606f1962f3a Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Victor=20Schr=C3=B6der?= <schrodervictor@gmail.com>
Date: Mon, 29 Jun 2015 23:28:55 +0200
Subject: [PATCH 26/26] Adds the check for 'not None' also when building
 host_info dict for ElastiCache clusters, nodes and replication groups

---
 plugins/inventory/ec2.py | 12 ++++++++----
 1 file changed, 8 insertions(+), 4 deletions(-)

diff --git a/plugins/inventory/ec2.py b/plugins/inventory/ec2.py
index 081990cd8f..864a64f5ed 100755
--- a/plugins/inventory/ec2.py
+++ b/plugins/inventory/ec2.py
@@ -1117,10 +1117,14 @@ class Ec2Inventory(object):
 
             # Target: Almost everything
             elif key == 'ec2_security_groups':
-                sg_ids = []
-                for sg in value:
-                    sg_ids.append(sg['SecurityGroupId'])
-                host_info["ec2_security_group_ids"] = ','.join([str(i) for i in sg_ids])
+
+                # Skip if SecurityGroups is None
+                # (it is possible to have the key defined but no value in it).
+                if value is not None:
+                    sg_ids = []
+                    for sg in value:
+                        sg_ids.append(sg['SecurityGroupId'])
+                    host_info["ec2_security_group_ids"] = ','.join([str(i) for i in sg_ids])
 
             # Target: Everything
             # Preserve booleans and integers