constellation/cli/internal/terraform/terraform.go
2022-09-30 16:50:52 +02:00

174 lines
4.3 KiB
Go

/*
Copyright (c) Edgeless Systems GmbH
SPDX-License-Identifier: AGPL-3.0-only
*/
package terraform
import (
"context"
"errors"
"github.com/edgelesssys/constellation/v2/internal/cloud/cloudprovider"
"github.com/edgelesssys/constellation/v2/internal/file"
"github.com/edgelesssys/constellation/v2/internal/state"
"github.com/hashicorp/go-version"
install "github.com/hashicorp/hc-install"
"github.com/hashicorp/hc-install/fs"
"github.com/hashicorp/hc-install/product"
"github.com/hashicorp/hc-install/releases"
"github.com/hashicorp/hc-install/src"
"github.com/hashicorp/terraform-exec/tfexec"
tfjson "github.com/hashicorp/terraform-json"
"github.com/spf13/afero"
)
const (
tfVersion = ">= 1.2.0"
terraformVarsFile = "terraform.tfvars"
)
// Client manages interaction with Terraform.
type Client struct {
tf tfInterface
provider cloudprovider.Provider
file file.Handler
state state.ConstellationState
remove func()
}
// New sets up a new Client for Terraform.
func New(ctx context.Context, provider cloudprovider.Provider) (*Client, error) {
tf, remove, err := GetExecutable(ctx, ".")
if err != nil {
return nil, err
}
file := file.NewHandler(afero.NewOsFs())
return &Client{
tf: tf,
provider: provider,
remove: remove,
file: file,
}, nil
}
// CreateCluster creates a Constellation cluster using Terraform.
func (c *Client) CreateCluster(ctx context.Context, name string, vars Variables) error {
if err := prepareWorkspace(c.file, c.provider); err != nil {
return err
}
if err := c.tf.Init(ctx); err != nil {
return err
}
if err := c.file.Write(terraformVarsFile, []byte(vars.String())); err != nil {
return err
}
if err := c.tf.Apply(ctx); err != nil {
return err
}
tfState, err := c.tf.Show(ctx)
if err != nil {
return err
}
ipOutput, ok := tfState.Values.Outputs["ip"]
if !ok {
return errors.New("no IP output found")
}
ip, ok := ipOutput.Value.(string)
if !ok {
return errors.New("invalid type in IP output: not a string")
}
c.state = state.ConstellationState{
CloudProvider: c.provider.String(),
LoadBalancerIP: ip,
}
return nil
}
// DestroyInstances destroys a Constellation cluster using Terraform.
func (c *Client) DestroyCluster(ctx context.Context) error {
return c.tf.Destroy(ctx)
}
// RemoveInstaller removes the Terraform installer, if it was downloaded for this command.
func (c *Client) RemoveInstaller() {
c.remove()
}
// CleanUpWorkspace removes terraform files from the current directory.
func (c *Client) CleanUpWorkspace() error {
if err := cleanUpWorkspace(c.file, c.provider); err != nil {
return err
}
if err := ignoreFileNotFoundErr(c.file.Remove("terraform.tfvars")); err != nil {
return err
}
if err := ignoreFileNotFoundErr(c.file.Remove("terraform.tfstate")); err != nil {
return err
}
if err := ignoreFileNotFoundErr(c.file.Remove("terraform.tfstate.backup")); err != nil {
return err
}
if err := ignoreFileNotFoundErr(c.file.Remove(".terraform.lock.hcl")); err != nil {
return err
}
if err := ignoreFileNotFoundErr(c.file.RemoveAll(".terraform")); err != nil {
return err
}
return nil
}
// GetState returns the state of the cluster.
func (c *Client) GetState() state.ConstellationState {
return c.state
}
// GetExecutable returns a Terraform executable either from the local filesystem,
// or downloads the latest version fulfilling the version constraint.
func GetExecutable(ctx context.Context, workingDir string) (terraform *tfexec.Terraform, remove func(), err error) {
inst := install.NewInstaller()
version, err := version.NewConstraint(tfVersion)
if err != nil {
return nil, nil, err
}
downloadVersion := &releases.LatestVersion{
Product: product.Terraform,
Constraints: version,
}
localVersion := &fs.Version{
Product: product.Terraform,
Constraints: version,
}
execPath, err := inst.Ensure(ctx, []src.Source{localVersion, downloadVersion})
if err != nil {
return nil, nil, err
}
tf, err := tfexec.NewTerraform(workingDir, execPath)
return tf, func() { _ = inst.Remove(context.Background()) }, err
}
type tfInterface interface {
Apply(context.Context, ...tfexec.ApplyOption) error
Destroy(context.Context, ...tfexec.DestroyOption) error
Init(context.Context, ...tfexec.InitOption) error
Show(context.Context, ...tfexec.ShowOption) (*tfjson.State, error)
}