troposfera: biblioteca para crear descripciones de AWS CloudFormation
La biblioteca de troposfera permite una creación más sencilla de AWS CloudFormation JSON escribiendo código Python para describir los recursos de AWS. troposphere también incluye soporte básico para recursos OpenStack a través de Heat.
Para facilitar la detección temprana de errores de CloudFormation o JSON, la biblioteca tiene verificación de propiedades y tipos integrada en las clases.
La troposfera se puede instalar utilizando el sistema de distribución pip para Python emitiendo:
$ pip install troposphere
Para instalar troposfera con awacs (dependencia suave recomendada):
$ pip install troposphere[policy]
Alternativamente, puedes usar setup.py para instalar clonando este repositorio y emitiendo:
$ python setup.py install # you may need sudo depending on your python installation
Un ejemplo sencillo para crear una instancia se vería así:
> >> from troposphere import Ref , Template
> >> import troposphere . ec2 as ec2
> >> t = Template ()
> >> instance = ec2 . Instance ( "myinstance" )
> >> instance . ImageId = "ami-951945d0"
> >> instance . InstanceType = "t1.micro"
> >> t . add_resource ( instance )
< troposphere . ec2 . Instance object at 0x101bf3390 >
> >> print ( t . to_json ())
{
"Resources" : {
"myinstance" : {
"Properties" : {
"ImageId" : "ami-951945d0" ,
"InstanceType" : "t1.micro"
},
"Type" : "AWS::EC2::Instance"
}
}
}
> >> print ( t . to_yaml ())
Resources :
myinstance :
Properties :
ImageId : ami - 951945 d0
InstanceType : t1 . micro
Type : AWS :: EC2 :: Instance
Alternativamente, se pueden usar parámetros en lugar de propiedades:
> >> instance = ec2 . Instance ( "myinstance" , ImageId = "ami-951945d0" , InstanceType = "t1.micro" )
> >> t . add_resource ( instance )
< troposphere . ec2 . Instance object at 0x101bf3550 >
Y add_resource()
devuelve el objeto para que sea fácil de usar con Ref()
:
> >> instance = t . add_resource ( ec2 . Instance ( "myinstance" , ImageId = "ami-951945d0" , InstanceType = "t1.micro" ))
> >> Ref ( instance )
< troposphere . Ref object at 0x101bf3490 >
Se está configurando una propiedad incorrecta en el recurso de AWS:
> >> import troposphere . ec2 as ec2
> >> ec2 . Instance ( "ec2instance" , image = "i-XXXX" )
Traceback ( most recent call last ):
...
AttributeError : AWS :: EC2 :: Instance object does not support attribute image
Tipo incorrecto de propiedad de recurso de AWS:
> >> ec2 . Instance ( "ec2instance" , ImageId = 1 )
Traceback ( most recent call last ):
...
TypeError : ImageId is < type 'int' > , expected < type 'basestring' >
Falta la propiedad requerida para el recurso de AWS:
> >> from troposphere import Template
> >> import troposphere . ec2 as ec2
> >> t = Template ()
> >> t . add_resource ( ec2 . Subnet ( "ec2subnet" , VpcId = "vpcid" ))
< troposphere . ec2 . Subnet object at 0x100830ed0 >
> >> print ( t . to_json ())
Traceback ( most recent call last ):
...
ValueError : Resource CidrBlock required in type AWS :: EC2 :: Subnet ( title : ec2subnet )
# Converted from EC2InstanceSample.template located at:
# http://aws.amazon.com/cloudformation/aws-cloudformation-templates/
from troposphere import Base64 , FindInMap , GetAtt
from troposphere import Parameter , Output , Ref , Template
import troposphere . ec2 as ec2
template = Template ()
keyname_param = template . add_parameter ( Parameter (
"KeyName" ,
Description = "Name of an existing EC2 KeyPair to enable SSH "
"access to the instance" ,
Type = "String" ,
))
template . add_mapping ( 'RegionMap' , {
"us-east-1" : { "AMI" : "ami-7f418316" },
"us-west-1" : { "AMI" : "ami-951945d0" },
"us-west-2" : { "AMI" : "ami-16fd7026" },
"eu-west-1" : { "AMI" : "ami-24506250" },
"sa-east-1" : { "AMI" : "ami-3e3be423" },
"ap-southeast-1" : { "AMI" : "ami-74dda626" },
"ap-northeast-1" : { "AMI" : "ami-dcfa4edd" }
})
ec2_instance = template . add_resource ( ec2 . Instance (
"Ec2Instance" ,
ImageId = FindInMap ( "RegionMap" , Ref ( "AWS::Region" ), "AMI" ),
InstanceType = "t1.micro" ,
KeyName = Ref ( keyname_param ),
SecurityGroups = [ "default" ],
UserData = Base64 ( "80" )
))
template . add_output ([
Output (
"InstanceId" ,
Description = "InstanceId of the newly created EC2 instance" ,
Value = Ref ( ec2_instance ),
),
Output (
"AZ" ,
Description = "Availability Zone of the newly created EC2 instance" ,
Value = GetAtt ( ec2_instance , "AvailabilityZone" ),
),
Output (
"PublicIP" ,
Description = "Public IP address of the newly created EC2 instance" ,
Value = GetAtt ( ec2_instance , "PublicIp" ),
),
Output (
"PrivateIP" ,
Description = "Private IP address of the newly created EC2 instance" ,
Value = GetAtt ( ec2_instance , "PrivateIp" ),
),
Output (
"PublicDNS" ,
Description = "Public DNSName of the newly created EC2 instance" ,
Value = GetAtt ( ec2_instance , "PublicDnsName" ),
),
Output (
"PrivateDNS" ,
Description = "Private DNSName of the newly created EC2 instance" ,
Value = GetAtt ( ec2_instance , "PrivateDnsName" ),
),
])
print ( template . to_json ())
Contamos con un grupo de Google, cloudtools-dev, donde puede hacer preguntas e interactuar con la comunidad de la troposfera. ¡Los problemas y las solicitudes de extracción siempre son bienvenidos!
troposfera tiene la licencia BSD de 2 cláusulas. Consulte LICENCIA para ver el texto completo de la licencia de la troposfera.