AWS: Cloud Formation: Is it possible to use multiple "DependsOn"? - json

Question

Given i have this example template:
{
"AWSTemplateFormatVersion" : "2010-09-09",
"Mappings" : {
"RegionMap" : {
"us-west-1" : { "AMI" : "ami-655a0a20" },
...
}
},
"Resources" : {
"Ec2Instance" : {
"Type" : "AWS::EC2::Instance",
"Properties" : {
...
},
"DependsOn" : "myDB"
},
"myDB" : {
"Type" : "AWS::RDS::DBInstance",
"Properties" : {
...
}
},
"myDB2" : {
"Type" : "AWS::RDS::DBInstance",
"Properties" : {
...
}
}
}
}
Is it possible to specify multiple DependsOn in any way?
Would be great to have somethink like:
"DependsOn" : ["myDB", "myDB2"]
Whats the normal way?

Answer 1

Yes,
The DependsOn attribute can take a single string or list of strings.
http://docs.aws.amazon.com/AWSCloudFormation/latest/UserGuide/aws-attribute-dependson.html
Syntax:
"DependsOn" : [ String, ... ]

Answer 2

This answer comes up first in Google, so I will include how to do multiple dependson attributes in YAML, which I found in this answer.
AnotherProductionResource:
Type: AWS::CloudFormation::Stack
Condition: ISProduction
DependsOn:
- AResource
- MyProductionResource
Properties:
[...]

Answer 3

Yes,
"DependsOn" can take multiple strings. I have listed an example below:
"DependsOn": [ "S3BucketAppElbLogs", "ElbLogAppBucketPolicy" ]

Answer 4

{
"Description": "Create a variable number of EC2 instance resources.",
"Parameters": {
"InstanceCount": {
"Description": "Number of EC2 instances (must be between 1 and 5).",
"Type": "Number",
"Default": 1,
"MinValue": 1,
"MaxValue": 5,
"ConstraintDescription": "Must be a number between 1 and 5."
},
"ImageId": {
"Description": "Image ID to launch EC2 instances.",
"Type": "AWS::EC2::Image::Id",
"Default": "ami-31c9924e"
},
"InstanceType": {
"Description": "Instance type to launch EC2 instances.",
"Type": "String",
"Default": "m3.medium",
"AllowedValues": [
"m3.medium",
"m3.large",
"m3.xlarge",
"m3.2xlarge"
]
}
},
"Conditions": {
"Launch1" : {"Fn::Equals" : [{"Ref" : "InstanceCount"}, "1"]},
"Launch2" : {"Fn::Equals" : [{"Ref" : "InstanceCount"}, "2"]}
},
"Resources": {
"Instance2": {
"Condition": "Launch2",
"Type": "AWS::EC2::Instance",
"Properties": {
"ImageId": {
"Ref": "ImageId"
},
"InstanceType": {
"Ref": "InstanceType"
}
},
"DependsOn": "Instance1"
},
"Instance1": {
"Condition": "Launch1",
"Type": "AWS::EC2::Instance",
"Properties": {
"ImageId": {
"Ref": "ImageId"
},
"InstanceType": {
"Ref": "InstanceType"
}
}
}
}
}