(pcl)=

Pulumi Configuration Language (PCL)

Pulumi Configuration Language (PCL) is an internal representation of Pulumi programs which supports all core concepts of the Pulumi programming model in a minimal form. Although not exposed directly to users today, this intermediate representation is used to support a variety of program conversion tasks, from and to various supported Pulumi languages.

Pulumi supports a number of operations pertaining to PCL programs:

• Lexing and parsing, in which PCL source is parsed into an abstract syntax tree (AST).

• Type checking and binding, in which a PCL AST is verified to be well-formed (describing resources, outputs, and so on), associated with ("bound to") a set of Pulumi schema, and type checked and resolved.

• Code generation ("programgen"), in which a PCL program is converted into a program written in a supported target language. Much of this underpins the core of tools such as pulumi convert.

(pcl-program)=

PCL programs

PCL programs are comprised of PCL source files which typically have the suffix .pp. This repository contains a large number of examples -- in particular, a large amount of PCL is used to drive language conformance tests. PCL programs support the following concepts:

(pcl-resource)=

Resources

Resources are defined as blocks of type resource. They correspond to stack resource registrations (see resource registration and for more). A resource block must have exactly two labels -- the first is the resource's name, to be used both as a reference to it elsewhere in the program and as its name in the resulting Pulumi stack (see the sections in this documentation on URNs and resource registration). The resource's body contains a set of attributes, which correspond to the resource's input properties. An optional options block may be used to specify resource options (e.g. provider, protect, ignoreChanges, etc.).

resource "r" "pkg:index:Resource" {
    name = "r"

    options {
        protect = true
    }
}

(pcl-component)=

Components

A component in the context of a PCL program is equivalent to the notion of a "local" component resource in a Pulumi program. Components are defined as blocks of type component. A component block must have two labels. The first is the component's name, to be used both as a reference to it elsewhere in the program and as its name in the resulting Pulumi stack. The second is a path to a directory containing a PCL program (set of .pp files) that defines the component's implementation. The component's body contains a set of attributes, which correspond to the component's input properties. An optional options block may be used to specify component options (e.g. provider, protect, etc.).

component "c" "./c" {
    name = "c"
    value = 42
}

Program generation for components results in e.g. the generation of local component types, such as those extending the ComponentResource class in SDKs exposing that type.

(pcl-output)=

Outputs

Outputs are defined as blocks of type output. They correspond exactly to exported stack outputs, such as pulumi.export in Python or ctx.Export in Go, which correspond to on the stack resource under the hood. Output blocks must have exactly one label, which is the output's name. The output's body must contain a single attribute, value, which is the output's value.

resource "r" "pkg:index:Resource" {
    name = "r"
}

output "o" {
    value = r.name
}

(pcl-config)=

Configuration

Configuration variables define the names and schema of values that are expected to be supplied to a program through Pulumi configuration (e.g. from a Pulumi.<stack>.yaml). They are defined as blocks of type config, with each block taking labels for the variable's name and type. The block's body may be used to specify other aspects of the variable, such as a description and default value. config blocks are typically used to generate program code for referring to Pulumi configuration, e.g. by creating and using a pulumi.Config() object in NodeJS.

config "key" "string" {
  description = "The key to use when encrypting data"
  default     = ""
}

(pcl-invoke)=

invoke

The invoke intrinsic is used to express provider function calls and corresponds to the 's method.

result1 = invoke("pkg:index:Function", { x = 3, y = 4 })

result2 = invoke("pkg:index:Function", { z = 5 }, { parent = p })

(pcl-call)=

call

The call intrinsic is used to express a method invocation on a resource and corresponds to the 's method.

resource "c" "pkg:index:Component" {
    ...
}

result = call(c, "method", { x = 3, y = 4 })

(pcl-builtin-function)=

Built-in functions

PCL offers a number of built-in functions for use in expressions. These are captured by the pulumiBuiltins function in .

:::{toctree} :maxdepth: 1 :titlesonly:

Syntax and type checking </pkg/codegen/hcl2/README> Binding </pkg/codegen/pcl/binding> :::