Support for associating to existing AWS Elastic IP

Signed-off-by: Elliot Murphy <statik@users.noreply.github.com>

requirements.txt

@@ -1 +1 @@
-ansible==2.5.2
+ansible==2.6.11

roles/cloud-ec2/files/stack.yml

@@ -11,6 +11,12 @@ Parameters:
     Type: String
   WireGuardPort:
     Type: String
+  UseThisElasticIP:
+    Type: String
+    Default: ''
+Conditions:
+  AllocateNewEIP: !Equals [!Ref UseThisElasticIP, '']
+  AssociateExistingEIP: !Not [!Equals [!Ref UseThisElasticIP, '']]
 Resources:
   VPC:
     Type: AWS::EC2::VPC
@@ -187,6 +193,7 @@ Resources:
 
   ElasticIP:
     Type: AWS::EC2::EIP
+    Condition: AllocateNewEIP
     Properties:
       Domain: vpc
       InstanceId: !Ref EC2Instance
@@ -194,6 +201,14 @@ Resources:
       - EC2Instance
       - VPCGatewayAttachment
 
+  ElasticIPAssociation:
+    Type: AWS::EC2::EIPAssociation
+    Condition: AssociateExistingEIP
+    Properties:
+      AllocationId: !Ref UseThisElasticIP
+      InstanceId: !Ref EC2Instance
+
+
 Outputs:
   ElasticIP:
-    Value: !Ref ElasticIP
+    Value: !GetAtt [EC2Instance, PublicIp]

roles/cloud-ec2/tasks/cloudformation.yml

@@ -12,6 +12,7 @@
       PublicSSHKeyParameter: "{{ lookup('file', SSH_keys.public) }}"
       ImageIdParameter: "{{ ami_image }}"
       WireGuardPort: "{{ wireguard_port }}"
+      UseThisElasticIP: "{{ use_existing_eip }}"
     tags:
       Environment: Algo
   register: stack

roles/cloud-ec2/tasks/prompts.yml

@@ -53,3 +53,28 @@
         [{{ default_region }}]
     register: _algo_region
   when: region is undefined
+
+- block:
+  - name: Get existing available Elastic IPs
+    ec2_eip_facts:
+    register: raw_eip_addresses
+
+  - set_fact:
+      available_eip_addresses: "{{ raw_eip_addresses.addresses | selectattr('association_id', 'undefined') | list }}"
+
+  - pause:
+      prompt: |
+        Do you want to use a pre-allocated Elastic IP?
+        (leave blank to allocate a new IP)
+          {% for eip in available_eip_addresses %}
+          {{ loop.index }}. {{ eip['public_ip'] }}
+          {% endfor %}
+          ['']
+    register: _use_existing_eip
+
+  - set_fact:
+      use_existing_eip: >-
+        {% if _use_existing_eip.user_input is defined and _algo_region.user_input != "" %}
+        {{ available_eip_addresses[_use_existing_eip.user_input | int -1 ]['allocation_id'] }}
+        {%- else %}{% endif %}
+  when: use_existing_eip is undefined