Documentation
¶
Overview ¶
Package terrajen implements a Go code generator for terraform.
A Terraform Provider Schemas object is needed to generate code. This can be obtained using the [Terraform CLI]. We have a helper for creating a provider schemas object: github.com/golingon/lingon/pkg/terragen.GenerateProvidersSchema
This package leverages github.com/dave/jennifer for generating Go code.
[Terraform CLI]: https://developer.hashicorp.com/terraform/cli/commands/providers/schema
Example ¶
package main
import (
"bytes"
"fmt"
"log/slog"
"github.com/golingon/lingon/pkg/internal/terrajen"
tfjson "github.com/hashicorp/terraform-json"
"github.com/zclconf/go-cty/cty"
)
var exampleProviderSchemas = tfjson.ProviderSchemas{
Schemas: map[string]*tfjson.ProviderSchema{
"registry.terraform.io/hashicorp/google": {
// Schema for the provider configuration
ConfigSchema: &tfjson.Schema{
Block: &tfjson.SchemaBlock{
Attributes: map[string]*tfjson.SchemaAttribute{
"field": {
AttributeType: cty.String,
Required: true,
},
},
},
},
// Schema for the resource configurations
ResourceSchemas: nil,
// Schema for the data source configurations
DataSourceSchemas: nil,
},
},
}
func main() {
// First you need to obtain a Terraform Provider Schema, which can be done
// using the
// terragen package.
// We will use some dummy data here
ps := exampleProviderSchemas
// Initialise the ProviderGenerator
gen := terrajen.ProviderGenerator{
// Filesystem location where to generate the files. This depends
// entirely on *where* you
// run the generator from
GeneratedPackageLocation: "./gen",
// Name of the provider
ProviderName: "google",
// Source of the provider
ProviderSource: "hashicorp/google",
// Version of the provider
ProviderVersion: "4.58.0",
}
// For each of the provider, resources and data sources in the provider
// schema, generate a
// terrajen.Schema object using our ProviderGenerator
prov := ps.Schemas["registry.terraform.io/hashicorp/google"]
provSchema := gen.SchemaProvider(prov.ConfigSchema.Block)
provFile := terrajen.ProviderFile(provSchema)
// Typically we would save the file, e.g. provFile.Save("provider.go").
// In this case we will write it to a buffer and print to stdout
var pb bytes.Buffer
if err := provFile.Render(&pb); err != nil {
slog.Error("rendering provider file", "error", err)
return
}
fmt.Println(pb.String())
// For each resource and data source (of which we have none), also do the
// same. E.g.
// for name, res := range prov.ResourceSchemas {}
// for name, data := range prov.DataSourceSchemas {}
}
Output: // CODE GENERATED BY github.com/golingon/lingon. DO NOT EDIT. package google import "github.com/golingon/lingon/pkg/terra" var _ terra.Provider = (*Provider)(nil) /* Provider is the provider for hashicorp/google. Documentation: https://registry.terraform.io/providers/hashicorp/google/4.58.0/docs */ type Provider struct { // Field is requred. Field terra.StringValue `hcl:"field,attr" validate:"required"` } // LocalName returns the provider local name for [Provider]. func (p *Provider) LocalName() string { return "google" } // Source returns the provider source for [Provider]. func (p *Provider) Source() string { return "hashicorp/google" } // Version returns the provider version for [Provider]. func (p *Provider) Version() string { return "4.58.0" } // Configuration returns the provider configuration for [Provider]. func (p *Provider) Configuration() interface{} { return p }
Index ¶
Examples ¶
Constants ¶
const HeaderComment = `CODE GENERATED BY github.com/golingon/lingon. DO NOT EDIT.`
Variables ¶
This section is empty.
Functions ¶
func DataSourceFile ¶
DataSourceFile generates a Go file for a Terraform data source configuration based on the given Schema
func ProviderFile ¶
ProviderFile generates a Go file for a Terraform provider configuration based on the given Schema
func ResourceFile ¶
ResourceFile generates a Go file for a Terraform resource configuration based on the given Schema
func SubPkgFile ¶
SubPkgFile generates a Go file for the given schema. The schema should represent a sub-package or be the sub-types of a top-level provider/resource/data source.
For example, the AWS provider has a top-level provider config, with many nested subtypes. SubPkgFile would generate a file containing all the subtypes.
Types ¶
type ProviderGenerator ¶
type ProviderGenerator struct {
// GeneratedPackageLocation is the directory on the filesystem where the
// generated Go files will be created.
// The GoProviderPkgPath path must match the location of the generated files
// so that they can be imported correctly.
// E.g. if we are in a Go module called "my-module" and we generate the
// files in a "gen" directory within the root of "my-module", then
// GoProviderPkgPath is "my-module/gen" and the GeneratedPackageLocation is
// "./gen" assuming we are running from the root of
// "my-module"
GeneratedPackageLocation string
// ProviderName is the local name of the provider.
// E.g. aws
// https://developer.hashicorp.com/terraform/language/providers/requirements#local-names
ProviderName string
// ProviderSource is the source address of the provider.
// E.g. registry.terraform.io/hashicorp/aws
// https://developer.hashicorp.com/terraform/language/providers/requirements#source-addresses
ProviderSource string
// ProviderVersion is the version of thr provider.
// E.g. 4.49.0
ProviderVersion string
}
ProviderGenerator is created for each provider and is used to generate the schema for each resource and data object, and the provider configuration. The schemas are used by the generator to create the Go files and sub packages.
func (*ProviderGenerator) SchemaData ¶
func (a *ProviderGenerator) SchemaData( name string, sb *tfjson.SchemaBlock, ) *Schema
SchemaData creates a schema for the given data object for the provider represented by ProviderGenerator
func (*ProviderGenerator) SchemaProvider ¶
func (a *ProviderGenerator) SchemaProvider(sb *tfjson.SchemaBlock) *Schema
SchemaProvider creates a schema for the provider config block for the provider represented by ProviderGenerator
func (*ProviderGenerator) SchemaResource ¶
func (a *ProviderGenerator) SchemaResource( name string, sb *tfjson.SchemaBlock, ) *Schema
SchemaResource creates a schema for the given resource for the provider represented by ProviderGenerator
type Schema ¶
type Schema struct {
Description string
Deprecated bool
SchemaType SchemaType // resource / provider / data
GoProviderPkgPath string // github.com/golingon/lingon/gen/providers
GeneratedPkgLocation string // gen/providers/aws
ProviderName string // aws
ProviderSource string // hashicorp/aws
ProviderVersion string // 4.49.0
PackageName string // aws_iam_role
Type string // aws_iam_role
// Structs
StructName string // Resource / DataSource / Provider
ArgumentStructName string // Args / DataArgs
AttributesStructName string // iam_role => awsIamRoleAttributes
StateStructName string // iam_role => awsIamRoleState
Receiver string // iam_role => ir
SubPkgName string // iam_role => iamrole
// SubPkgPath is the filepath for the schema entities types (args,
// attributes, state).
SubPkgPath string // aws_iam_role
FilePath string // gen/providers/aws/ xxx
// contains filtered or unexported fields
}
Schema is used to store all the relevant information required for the Go code generator. A schema can represent a resource, a data object or the provider configuration.
func (*Schema) SubPkgQualPath ¶
type SchemaType ¶
type SchemaType string
const ( SchemaTypeProvider SchemaType = "provider" SchemaTypeResource SchemaType = "resource" SchemaTypeDataSource SchemaType = "data" )
Source Files