Pulumi YAML reference
Pulumi programs can be defined in many languages, and the Pulumi YAML dialect offers an additional language for authoring Pulumi programs.
The Pulumi YAML provider supports programs written in YAML or JSON. In both cases, the programs (.yaml
or .json
files) follow a simple schema, including four top level sections:
Property | Type | Required | Expression | Description |
---|---|---|---|---|
config | config options | No | No | Config specifies the Pulumi config inputs to the deployment. |
resources | map[string]Resource | No | No | Resources declares the Pulumi resources that will be deployed and managed by the program |
variables | map[string]Expression | No | Yes | Variables specifies intermediate values of the program, the values of variables are expressions that can be re-used. |
outputs | map[string]Expression | No | Yes | Outputs specifies the Pulumi stack outputs of the program and how they are computed from the resources is a value of the appropriate type for the template to use if no value is specified. |
In many locations within this schema, values may be expressions which computed a value based on the config
, variables
, or outputs of resources
. These expressions can be provided in two ways:
- If an object is provided as a value, and has a key that has the prefix
fn::
, the object is treated as an expression, and the expression will be resolved to a new value that will be used in place of the object. - Any string value is interpreted as an interpolation, with
${...}
being replaced by evaluating the expression in the...
.
The supported expression forms for each of these is detailed below.
Config
config
is a map of config property keys to either values or structured declarations (see here).
In beta, Pulumi YAML projects used the configuration
key. This will eventually be deprecated; switching from configuration
to config
will not break existing projects.
The value of configuration
is an object whose keys are logical names by which the config input will be referenced in expressions within the program, and whose values are elements of the schema below. Each item in this object represents an independent config input. Either type
or default
is required.
Property | Type | Required | Expression | Description |
---|---|---|---|---|
type | string | No | No | Type is the (required) data type for the parameter. It can be one of: String , Number , List<Number> , or List<String> . |
default | any | No | No | Default is a value of the appropriate type for the template to use if no value is specified. |
secret | bool | No | No | Secret specifies if the config value should be encrypted as a secret. |
Resources
The value of resources
is an object whose keys are logical resource names by which the resource will be referenced in expressions within the program, and whose values which are elements of the schema below. Each item in this object represents a resource which will be managed by the Pulumi program.
Property | Type | Required | Expressions | Description |
---|---|---|---|---|
type | string | Yes | No | Type is the Pulumi type token for this resource. |
defaultProvider | bool | No | No | DefaultProvider specifies if a provider should be used for resources without an explicit one set. Set only on provider resources. |
properties | map[string]Expression | No | Yes | Properties contains the primary resource-specific keys and values to initialize the resource state. |
options | Resource Options | No | No | Options contains all resource options supported by Pulumi. |
get | Resource Getter | No | Yes | A getter function for the resource. Supplying get is mutually exclusive to properties . |
Resource Options
The value of the options
property of a Resource is an object whose keys are resource option names and whose values are elements of the schema below. No resource options are required.
The dependsOn
, parent
, provider
, and providers
values permit expressions which must use interpolation syntax to reference resources by name. For example:
options:
provider: ${myEksProvider}
providers:
aws: ${myAwsProvider}
dependsOn:
- ${otherResource}
parent: ${someParentResource}
Property | Type | Description |
---|---|---|
additionalSecretOutputs | string[] | AdditionalSecretOutputs specifies properties that must be encrypted as secrets |
aliases | string[] | Aliases specifies names that this resource used to have, so that renaming or refactoring doesn’t replace it |
customTimeouts | Custom Timeout | CustomTimeouts overrides the default retry/timeout behavior for resource provisioning |
deleteBeforeReplace | bool | DeleteBeforeReplace overrides the default create-before-delete behavior when replacing |
dependsOn | Expression[] | DependsOn makes this resource explicitly depend on another resource, by name, so that it won’t be created before the dependent finishes being created (and the reverse for destruction). Normally, Pulumi automatically tracks implicit dependencies through inputs/outputs, but this can be used when dependencies aren’t captured purely from input/output edges. |
ignoreChanges | string[] | IgnoreChanges declares that changes to certain properties should be ignored during diffing |
import | string | Import adopts an existing resource from your cloud account under the control of Pulumi |
parent | Expression | Parent specifies a parent for the resource |
protect | bool | Protect prevents accidental deletion of a resource |
provider | Expression | Provider specifies an explicitly configured provider, instead of using the default global provider |
providers | map[string]Expression | Map of providers for a resource and its children. |
version | string | Version specifies a provider plugin version that should be used when operating on a resource |
pluginDownloadURL | string | PluginDownloadURL specifies a provider plugin download URL |
replaceOnChanges | string[] | ReplaceOnChanges specifies if changes to certain properties on a resource should force replacement instead of an in-place update. |
retainOnDelete | bool | RetainOnDelete causes a resource to be preserved in the cloud even when it is deleted from the Pulumi state. |
Resource Getter
Supplying a get
key turns the resource declaration into a Getter Function.
Property | Type | Required | Description |
---|---|---|---|
id | string | Yes | The ID of the resource to import |
state | map[string]Expression | No | Known properties (input & output) of the resource. This assists the provider in figuring out the correct resource. |
Custom Timeout
The optional customTimeouts
property of a resource is an object of the following schema:
Property | Type | Required | Expression | Description |
---|---|---|---|---|
create | string | No | No | Create is the custom timeout for create operations. |
delete | string | No | No | Delete is the custom timeout for delete operations. |
update | string | No | No | Update is the custom timeout for update operations. |
Providers and provider versions
There are at least two reasons to explicitly define providers in YAML, or explicitly set their versions while creating resources.
- Using explicit versions enables pinning the dependencies used, a technique used to improve build reliability.
- Using explicit providers enables controlling the options for providers used by each resource, as described in Unlock Programmatic Control by Disabling Default Providers.
If a specific provider version is necessary, we prefer the approaches in the order described here.
Default provider
Declaring a default provider simplifies configuring a provider version across all resources for that provider.
To configure the default provider instance for all resources for that provider’s name, use the resources
section to declare a provider resource.
For the type
property, prefix the name of the provider with pulumi:providers
, for example, pulumi:providers:aws
. Setting the defaultProvider
property to true
, defined at the same level as type
, configures this as a default provider.
resources:
aws-provider:
type: pulumi:providers:aws
defaultProvider: true
options:
version: 6.45.0
my-bucket:
type: aws:s3:Bucket
In this example the my-bucket
resource, and any other AWS resources, uses the default AWS provider version 6.45.0.
Only one provider of a given type
can be declared as the default provider.
Explicit provider
To declare an explicit provider instance for specific resources, declare a provider resource in the resources
section. For the type
property, prefix the name of the provider with pulumi:providers
.
resources:
provider:
type: pulumi:providers:azure
options:
version: 5.1.0
The provider instance can than be used as described in section Resource Options by setting the provider
option:
resources:
provider:
type: pulumi:providers:azure
options:
version: 5.1.0
rg:
type: azure:core:ResourceGroup
properties:
location: WestEurope
options:
provider: ${provider}
Explicit providers take precedence over default providers.
Resource version
To declare a resource with a specific provider version use the version
option as described in Resource Options:
resources:
something:
type: aws:s3:Bucket
properties:
...
options:
version: 5.6.0
Third party providers
Third party providers may require a pluginDownloadURL
option for Pulumi to acquire the provider plugin. The publisher of that provider should provide this URL, following our guide for Authoring & Publishing.
All of the above examples setting a version
with a default provider, explicit provider, or on individual resources may be combined with the pluginDownloadURL
option to use a third party provider.
This declares one of Pulumi’s own providers as a default provider, setting an explicit pluginDownloadURL
.
resources:
aws-provider:
type: pulumi:providers:aws
defaultProvider: true
options:
version: 6.45.0
pluginDownloadURL: github://api.github.com/pulumi
my-bucket:
type: aws:s3:Bucket
Outputs and Stack References
The value of outputs
is an object whose keys are the logical names of the outputs that are available from outside the Pulumi stack (via pulumi stack output
), and whose values are potentially computed expressions that resolve to the values of the desired outputs.
outputs:
outputName: ${resource.id}
Stack references can be used to access the outputs of one stack from within another stack. A stack reference requires the fully qualified name of the stack as an argument in the format of <organization>/<project>/<stack>
.
resources:
reference:
type: pulumi:pulumi:StackReference
properties:
name: org/project/stack
outputs:
secondOutputName: ${reference.outputs["outputName"]}
The above output will have the value of the outputName
output from the stack org/project/stack
.
Expressions
Expressions can be used in several contexts:
- the properties of
properties
ofresources
- the properties of
options
ofresources
that take references to other resources:parent
,dependsOn
,provider
, andproviders
- the values of
variables
andoutputs
- some or all values provided to built-in functions, as specified below
Generally speaking, most values permit an expression and exceptions will be documented as not permitting an expression, as above.
In these contexts, any JSON/YAML value may be provided. If that value is a string, it is interpolated. If that value is an object, and the object has a key with a prefix of fn::
, it is evaluated as an expression.
Interpolation
In expression locations, strings are evaluated as interpolations and any nested ${...}
expressions within the string value are replaced by the value of the expression ...
. The syntax of expressions within interpolations permits property access only.
To use ${}
in a string literal, escape $
with $$
like so:
variables:
plainString: $${value}
A string like Hello, ${foo}
will convert the expression foo
to a string.
If a string contains only an ${...}
expression, it’s considered a substitution.
Property Access
Within an expression denoted by ${...}
property access is permitted according to the forms below. Config, variables, and resource keys all exist in a single namespace, and in the examples, root
or equivalent must be the name of one of these items, and it must be valid to access the foo
property of that item if it’s a map or object, or if it’s an array, the index must be valid.
${root}
${root.foo}
${root["foo"]}
${root.bar.quux}
${root["bar"].quux}
${root["bar"]["quux"]}
${root[0]}
${root[100]}
${root[0].foo}
${root[0][1].foo}
${root.foo.items[0].bar[1]}
${root["key with \"escaped\" quotes"]}
${root["key with a ."]}
${["root key with \"escaped\" quotes"].foo}
${["root key with a ."][100]}
We have not discussed types until now, but implicitly every expression has a type, such as number, string, map, array, or even resource. When interpolated, these values must become strings, otherwise they are substituted in. Additionally:
- maps must have string keys and expression values
- arrays have non-negative integer indices and expression values
- property access on a Resource retrieves outputs
Substitution
Expressions denoted by ${...}
are only converted to strings when interpolated into a string with surrounding text. If a resource property takes a list or a map for example, that can be provided by a variable whose value can be substituted in. In the example below, the httpPort
variable is used to reduce repetition in the two Kubernetes Service resources.
name: kubernetes-port-example
variables:
httpPort:
protocol: TCP
port: 80
targetPort: 8000
resources:
serviceOne:
type: kubernetes:core/v1:Service
properties:
spec:
selector:
app: "MyApp"
ports:
- ${httpPort}
serviceTwo:
type: kubernetes:core/v1:Service
properties:
spec:
selector:
app: "OtherApp"
ports:
- ${httpPort}
The last two lines are equivalent as if the variable were substituted for its value:
ports:
- protocol: TCP
port: 80
targetPort: 8000
Built-in Functions
In any expression location, an object containing a single key beginning with fn::
calls a built-in function.
fn::toBase64
Converts a UTF-8 string into a Base64 encoded string using the standard encoding.
variables:
greeting:
fn::toBase64: "Hello, world!"
The expression ${greeting}
will return SGVsbG8sIHdvcmxkIQ==
fn::fromBase64
Converts a Base64 encoded string into a UTF-8 string. This will fail if the result is not a valid UTF-8 string
variables:
greeting:
fn::fromBase64: SGVsbG8sIFdvcmxkIQ==
The expression ${greeting}
will return Hello, World!
fn::toJSON
Converts a value into its JSON representation.
variables:
item:
fn::toJSON:
key1: value1
key2: 123
The expression ${item}
will return a JSON value { "key1": "value1", "key2": 123 }
.
fn::invoke
Calls a function from a package and returns either the whole object or a single field if given the return
property. This can be any of the functions in the registry providers as well as functions found in the pulumi-std package that includes math functions such as sum
and abs
, logic functions such as anytrue
, and string functions such as split
.
The schema is:
Property | Type | Required | Expression | Description |
---|---|---|---|---|
function | string | Yes | No | Name of a function to call. |
arguments | map[string]Expression | Yes | Yes | Arguments to pass to the expression, each key is a named argument. |
options | Invoke Options | No | No | Options for the provider calling the function. |
return | string | No | No | Return the value of the field with this name. |
Example calling the getAmi function in the AWS provider package:
variables:
AmazonLinuxAmi:
fn::invoke:
function: aws:getAmi
arguments:
filters:
- name: name
values: ["amzn-ami-hvm-*-x86_64-ebs"]
owners: ["137112412989"]
mostRecent: true
options:
version: 5.9.0
return: id
The expression ${AmazonLinuxAmi}
will return the AMI ID returned from the aws:getAmi
function.
Example calling the sum
function in the pulumi-std
provider package to subtract 255 from ${route53Weight}
:
variables:
route53Weight: 400
modifiedWeight:
fn::invoke:
function: std:sum
arguments:
input:
- ${route53Weight}
- -255
return: result
The expression ${modifiedWeight}
will return 145
in this case.
Invoke Options
The value of the options
property of an fn::invoke is an object with the following properties.
The parent
and provider
values permit expressions which must use interpolation syntax to reference resources by name. For example:
options:
provider: ${myEksProvider}
parent: ${someParentResource}
Property | Type | Description |
---|---|---|
parent | Expression | Parent specifies a parent for the resource |
provider | Expression | Provider specifies an explicitly configured provider, instead of using the default global provider |
version | string | Version specifies a provider plugin version that should be used when operating on a resource |
pluginDownloadURL | string | Version specifies a URL that should be used when to download the provider plugin |
fn::join
Joins strings together separated by a delimiter. Arguments are passed as a list, with the first item being the delimiter, and the second item a list of expressions to concatenate.
variables:
banana:
fn::join:
- 'NaN'
- - Ba
- a
The expression ${banana}
will have the value "BaNaNa"
.
fn::split
Splits a string on a delimiter. Arguments are passed as a list, with the first item being the delimiter, and the second item the string to split.
variables:
fruits:
fn::split:
- ", "
- "apple, orange, banana"
The expression ${fruits}
will be a list containing the values ["apple", "orange", "banana"]
.
fn::select
Selects one of several options given an index. Arguments are passed as a list, with the first item being the index, 0-based, and the second item a list of expressions to select from.
variables:
policyVersion:
fn::select:
- 1
- - v1
- v1.1
- v2.0
The expression ${policyVersion}
will have the value v1.1
.
fn::*Asset
and fn::*Archive
Assets and Archives are intrinsic types to Pulumi, like strings and numbers, and some resources may take these as inputs or return them as outputs. The built-ins create each kind of asset or archive. Each takes all take a single string value.
Built-In | Argument Type | Description |
---|---|---|
fn::fileAsset | string | The contents of the asset are read from a file on disk. |
fn::stringAsset | string | The contents of the asset are read from a string in memory. |
fn::remoteAsset | string | The contents of the asset are read from an http, https or file URI. |
fn::fileArchive | string | The contents of the archive are read from either a folder on disk or a file on disk in one of the supported formats: .tar, .tgz, .tar.gz, .zip or .jar. |
fn::remoteArchive | string | The contents of the asset are read from an http, https or file URI, which must produce an archive of one of the same supported types as FileArchive. |
fn::assetArchive | map | The contents of the archive are read from a map of either Asset or Archive objects, one file or folder respectively per entry in the map. |
variables:
aFile:
fn::fileAsset: ./file.txt
aString:
fn::stringAsset: Hello, world!
aRemoteAsset:
fn::remoteAsset: http://worldclockapi.com/api/json/est/now
aFileArchive:
fn::fileArchive: ./file.zip
aRemoteArchive:
fn::remoteArchive: http://example.com/file.zip
anAssetArchive:
fn::assetArchive:
file:
fn::stringAsset: Hello, world!
folder:
fn::fileArchive: ./folder
fn::secret
Constructs a Secret from an existing value.
variables:
secret:
fn::secret:
fn::invoke:
function: my:pkg:GetSecretValue
fn::readFile
Reads a file from disk and returns the contents as a string, must be utf-8. This function has special rules for its behavior.
variables:
someText:
fn::readFile: ./README.md
Any subpath of the Pulumi project directory is allowed, whether it is absolute, relative, constant, or an expression:
fn::readFile: ./README.md
, a relative subpathfn::readFile: ${pulumi.cwd}/example.txt
, an absolute subpathfn::readFile: /opt/project-dir/example.json
, an absolute subpath if the program is in /opt/project-dir
Absolute paths to any location are allowed if they are constants:
fn::readFile: /etc/lsb-release
fn::readFile: /usr/share/nginx/html
fn::readFile: /var/run/secrets/kubernetes.io/serviceaccount/token
Relative paths that escape the project directory and absolute paths that are non-constant are forbidden to prevent path traversals.
fn::readFile: ../../etc/shadow
, a relative path that escapes the projectfn::readFile: ${pulumi.cwd}/../../.ssh/id_rsa.pub
, an expression that returns an absolute path that escapes the project
Built-in variables
Built-in variables accessible within any Pulumi YAML program.
pulumi
The built-in pulumi
variable contains three properties, which can be useful for retrieving information
about your current workspace.
variables:
cwd: ${pulumi.cwd}
project: ${pulumi.project}
stack: ${pulumi.stack}
${pulumi.cwd}
retrieves the current working directory${pulumi.project}
retrieves the current project${pulumi.stack}
retrieves the current stack
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