ยปTerraform Concepts
Schemas specify the fields that a provider, resource or data source configuration can have.
The fields defined within the schema are either attributes or blocks.
Attributes and blocks within Terraform configuration have different syntax, either using, or omitting an equals sign in their definition, respectively.
Providers, resources and data sources have their own type-specific schema, which use type-specific attributes and blocks.
The following examples use a resource but the same schema attribute and block types are also defined with the schema for providers and data sources. The examples focus on type-related information, the Optional field is included just to provide working examples but refer to Schema for information about the other fields that can be defined within attributes and blocks.
Attributes
Attributes are used to set values.
| Attribute Type | Description |
|---|---|
| BoolAttribute | Boolean values (i.e., true/false) |
| Float64Attribute | 64 bit floating point number values |
| Int64Attribute | 64 bit integer number values |
| NumberAttribute | Generic number with up to 512 bits of floating point or integer precision |
| StringAttribute | String values |
| ListAttribute | List with a single element type (e.g., types.StringType) |
| MapAttribute | Map with a single element type (e.g., types.Int64Type) |
| SetAttribute | Set with a single element type (e.g., types.BoolType) |
| ObjectAttribute | Object with only type information for underlying attributes |
| ListNestedAttribute | List containing nested objects where the object attributes can be fully defined |
| MapNestedAttribute | Map containing nested objects where the object attributes can be fully defined |
| SetNestedAttribute | Set containing nested objects where the object attributes can be fully defined |
| SingleNestedAttribute | Single object where the object attributes can be fully defined |
Refer to Attributes - Terraform Configuration and Schema for examples of Terraform configuration and schema that illustrate the usage of the various types of schema attributes.
Blocks
The Terraform language uses a block as a container for other attributes and blocks. Terraform implements many top level blocks, such as provider and resource, while providers can implement nested blocks in their schema to enable practitioners to configure data.
Use nested attributes for new schema implementations. Block support is mainly for migrating prior SDK-based providers.
The available nesting modes are:
- List: Ordered collection of objects
- Set: Unordered collection of objects
- Single: One object
Refer to Blocks - Terraform Configuration for examples of Terraform configuration and schema that illustrate the usage of nested blocks.