Aws-cli: Syntax for template parameters with cloudformation create-stack is inscruitable

[nonspecialist]

Given a simple template:

{
    "AWSTemplateFormatVersion":"2010-09-09",
    "Description":"Example template",
    "Parameters":{
        "ExampleParameter":{
            "Type":"Number"
        }
    },
    "Resources":{
        "ExampleVolume":{ 
            "Type":"AWS::EC2::Volume",
            "Properties":{
                "AvailabilityZone":"us-east-1a",
                "Size":"10",
                "Tags": [ 
                    { "FirstTag" : { "Ref" : "ExampleParameter" } }
                ]
    }
}

then the syntax for providing a value for ExampleParameter on the command line is ... well, I can't work it out.

I'm using the following:

aws cloudformation create-stack --stack-name test-stack --template-body "<template>" --parameters file:parameters-file

and the contents of parameters-file as being any of:

["ExampleParameter":1234]
["ExampleParameter":"1234"]
{ ["ExampleParameter":"1234"] }
[{"Parameter":{"ParameterKey":"ExampleParameter","ParameterValue":"1234"}}]
{ "Parameters": [ "ExampleParameter":{"ParameterKey":"ExampleParameter","ParameterValue":"1234"}]}

and a bunch of other, more wacky manglings, but I just cannot get it to work.

Edit: many of the bad inputs get response from botocore like:

Expecting , delimiter: line 1 column 19 (char 19)

and those inputs that do get parsed get a response from AWS like:

{
"ErrorResponse": {
    "RequestId": "d0fc4af5-7a55-11e2-afd2-23222bc4e432", 
    "Error": {
        "Message": "Template requires parameter: ExampleParameter", 
        "Code": "ValidationError", 
        "Type": "Sender"
    }
}
}

Some examples or advice would be welcome ...

[nonspecialist]

Further information: running with --debug shows me that even though parameters are getting parsed in the forms which work, none of them are being sent in the POST.

(I also notice that I left out two closing braces in the template ... sorry for the transcription error)

snippets from --debug:

...
2013-02-19 16:41:30,558 - botocore.parameters - DEBUG - name: Parameters
2013-02-19 16:41:30,558 - botocore.parameters - DEBUG - label: 
...
send: 'POST / HTTP/1.1\r\nHost: cloudformation.us-east-1.amazonaws.com\r\nAccept-Encoding: identity\r\nContent-Length: 529\r\nContent-Type: application/x-www-form-urlencoded\r\nAuthorization: AWS4-HMAC-SHA256 Credential=xxxxxxxxxxxxx/20130219/us-east-1/cloudformation/aws4_request, SignedHeaders=host;user-agent;x-amz-date, Signature=xxxxxxxx\r\nX-Amz-Date: 20130219T054130Z\r\nUser-Agent: aws-cli/0.5.3 Python/2.7.3 Linux/3.7.6-102.fc17.x86_64\r\n\r\nStackName=example&Action=CreateStack&Version=2010-05-15&TemplateBody=%7B%22AWSTemplateFormatVersion%22%3A%222010-09-09%22%2C%22Description%22%3A%22Example+template%22%2C%22Parameters%22%3A%7B%22ExampleParameter%22%3A%7B%22Type%22%3A%22Number%22%7D%7D%2C%22Resources%22%3A%7B%22ExampleVolume%22%3A%7B%22Properties%22%3A%7B%22AvailabilityZone%22%3A%22us-east-1a%22%2C%22Size%22%3A%2210%22%2C%22Tags%22%3A%5B%7B%22FirstTag%22%3A%7B%22Ref%22%3A%22ExampleParameter%22%7D%7D%5D%7D%2C%22Type%22%3A%22AWS%3A%3AEC2%3A%3AVolume%22%7D%7D%7D'
reply: 'HTTP/1.1 400 Bad Request\r\n'

[nonspecialist]

Okay, I figured it out ... I hope this issue (and comment) helps others.

The correct syntax is:

[{"parameter_key":"ExampleParameter","parameter_value":"1234"}]

If you need to supply multiple parameters, the syntax is:

[ {"parameter_key":"Param1","parameter_value":"1234"},{"parameter_key":"Param2","parameter_value":"1234"} ]

This did my head in for a while.

[garnaat]

Thanks for your diligence 8^) We acknowledge that the actual format of complex parameters is currently difficult to decipher. We are working on a couple of ways to improve this. I'll update this ticket when this work has been completed.

[tomstockton]

What's the correct syntax for passing the parameters on the command line rather than as a 'file:'?

[nonspecialist]

Hi Tom,

The syntax for command-line use is the same; using a file: prefix just makes it pull the contents from a file instead of from stdin. Of course, this may present some interesting challenges with quoting, shell metacharacters, and so on but for the most part it's straightforward.

Example:

$ aws cloudformation create-stack --stack-name my-test-stack \
    --template-body file:my-template.json \
    --parameters '[{"parameter_key":"KeyName","parameter_value":"my-ssh-keyname"}]'

[tomstockton]

Thanks for that, I was trying to wrap the JSON list in single quoted braces. Didn't think to just single quote the list.

I'm having more fun now!

[sebsto]

What is the new syntax these days ?
I just tried the syntax described by @nonspecialist above but it seems it does not work anymore

I am using

$ aws --version
aws-cli/0.16.0 Python/2.7.2 Darwin/12.4.0
$ pip list | grep boto
boto (2.11.0)
botocore (0.16.0)

I tested this format

[{"parameter_key":"name", "parameter_value":"test"}]

And received

Invalid value ('parameter_key') for param element of list:Parameters of type list

[adrianmeca]

I just run into the same issue, now the format seems to be [{"ParameterKey":"name", "ParameterValue":"test"}]

For the single quote I believe that with a single note on the official documentation or the help command will do: "Note: for the json sintax single quote the json string" it would save lots of headaches

[onetom]

Why is it necessary to specify a hash of ParameterKey and ParameterValue instead of creating the hash directly?
{ "name": "value", "instance": "i-03fa8d" }
is a lot more readable than
[ {"ParameterKey": "name", "ParameterValue": "test"}, {"ParameterKey": "instance", "ParameterValue": "i-03fa8d"} ]

[onetom]

I see it's possible to have some abbreviation, like:

--parameters ParameterKey=Vpc,ParameterValue=vpc-1f616a7d ParameterKey=SubnetA,ParameterValue=subnet-44e1e926 ParameterKey=SubnetB,ParameterValue=subnet-36d8f342

but that's still pretty ugly compared to

--parameters Vpc=vpc-1f616a7d, SubnetA=subnet-44e1e926, SubnetB=subnet-36d8f342

and it's especially annoying, since u have to specify these again when u r doing an aws cloudformation update-stack ...

[garnaat]

See #484. This is being actively worked and we hope to have an improved UI available for map-like values in the future.

[pputnik]

hi All,
Any improvement here since 2013? Any way to use '--parameters file:///...' instead of list of parameters?
Thank you.

[gnaresh19]

Any update on the above request to use '--parameters file:///...' instead of list of parameters ?

Thanks!