feat: dont register instance when metadata service give us bad results (#188)

Author: TheOutdoorProgrammer

.spacelift/config.yml

@@ -1,5 +1,5 @@
 version: 2
-module_version: 5.4.1
+module_version: 5.4.2
 
 tests:
   - name: AMD64-based workerpool

user_data/saas.tftpl

@@ -65,12 +65,26 @@ spacelift () {(
   echo "Making the Spacelift launcher executable" >> /var/log/spacelift/info.log
   chmod 755 /usr/bin/spacelift-launcher 2>>/var/log/spacelift/error.log
 
+  validate_metadata() {
+    local value="$1"
+    local name="$2"
+    if [[ -z "$value" ]] || [[ "$value" == "null" ]] || [[ "$value" == "None" ]]; then
+      echo "ERROR: $name is null or empty. EC2 metadata service returned invalid data." >> /var/log/spacelift/error.log
+      return 1
+    fi
+    return 0
+  }
+
   echo "Retrieving EC2 instance id and AMI id" >> /var/log/spacelift/info.log
   export SPACELIFT_METADATA_instance_id=$(ec2-metadata --instance-id | cut -d ' ' -f2)
+  validate_metadata "$SPACELIFT_METADATA_instance_id" "instance_id" || return 1
+
   export SPACELIFT_METADATA_ami_id=$(ec2-metadata --ami-id | cut -d ' ' -f2)
+  validate_metadata "$SPACELIFT_METADATA_ami_id" "ami_id" || return 1
 
   echo "Retrieving EC2 ASG ID" >> /var/log/spacelift/info.log
   export SPACELIFT_METADATA_asg_id=$(aws autoscaling --region=${region} describe-auto-scaling-instances --instance-ids $SPACELIFT_METADATA_instance_id | jq -r '.AutoScalingInstances[0].AutoScalingGroupName')
+  validate_metadata "$SPACELIFT_METADATA_asg_id" "asg_id" || return 1
 
   echo "Starting the Spacelift binary" >> /var/log/spacelift/info.log
   /usr/bin/spacelift-launcher 1>>/var/log/spacelift/info.log 2>>/var/log/spacelift/error.log

user_data/selfhosted.tftpl

@@ -77,11 +77,25 @@ create_spacelift_launcher_script () {(
 #!/bin/bash
 join_strings () { local d="$1"; echo -n "$2"; shift 2 && printf '%s' "$${!@/#/$d}"; }
 
+validate_metadata() {
+  local value="\$1"
+  local name="\$2"
+  if [[ -z "\$value" ]] || [[ "\$value" == "null" ]] || [[ "\$value" == "None" ]]; then
+    echo "ERROR: \$name is null or empty. EC2 metadata service returned invalid data." >> /var/log/spacelift/error.log
+    exit 1
+  fi
+}
+
 echo "Retrieving EC2 instance ID and ami ID" >> /var/log/spacelift/info.log
 export SPACELIFT_METADATA_instance_id=\$(ec2-metadata --instance-id | cut -d ' ' -f2)
+validate_metadata "\$SPACELIFT_METADATA_instance_id" "instance_id"
+
 export SPACELIFT_METADATA_ami_id=\$(ec2-metadata --ami-id | cut -d ' ' -f2)
+validate_metadata "\$SPACELIFT_METADATA_ami_id" "ami_id"
+
 echo "Retrieving EC2 ASG ID" >> /var/log/spacelift/info.log
 export SPACELIFT_METADATA_asg_id=\$(aws autoscaling --region=${region} describe-auto-scaling-instances --instance-ids \$SPACELIFT_METADATA_instance_id | jq -r '.AutoScalingInstances[0].AutoScalingGroupName')
+validate_metadata "\$SPACELIFT_METADATA_asg_id" "asg_id"
 if [[ "${http_proxy_config}" != "" || "${https_proxy_config}" != "" || "${no_proxy_config}" != "" ]]; then
   whitelisted_vars=()
   echo "Configuring HTTP proxy information" >> /var/log/spacelift/info.log