tflint: Add Runner.Config()

Author: wata727

helper/runner.go

@@ -1,10 +1,13 @@
 package helper
 
 import (
+	"fmt"
+
 	"github.com/hashicorp/go-version"
 	"github.com/hashicorp/hcl/v2"
 	"github.com/hashicorp/hcl/v2/gohcl"
 	"github.com/terraform-linters/tflint-plugin-sdk/terraform"
+	"github.com/terraform-linters/tflint-plugin-sdk/terraform/configs"
 	"github.com/terraform-linters/tflint-plugin-sdk/tflint"
 	"github.com/zclconf/go-cty/cty/gocty"
 )
@@ -203,6 +206,74 @@ func (r *Runner) Backend() (*terraform.Backend, error) {
 	return nil, nil
 }
 
+// Config returns the Terraform configuration
+func (r *Runner) Config() (*configs.Config, error) {
+	config := &configs.Config{
+		Module: &configs.Module{},
+	}
+
+	for _, file := range r.Files {
+		content, diags := file.Body.Content(configFileSchema)
+		if diags.HasErrors() {
+			return nil, diags
+		}
+
+		for _, block := range content.Blocks {
+			switch block.Type {
+			case "terraform":
+				content, diags := block.Body.Content(terraformBlockSchema)
+				if diags.HasErrors() {
+					return nil, diags
+				}
+
+				for _, block := range content.Blocks {
+					switch block.Type {
+					case "backend":
+						config.Module.Backend = &terraform.Backend{
+							Type:      block.Labels[0],
+							TypeRange: block.LabelRanges[0],
+							Config:    block.Body,
+							DeclRange: block.DefRange,
+						}
+					case "required_providers":
+						// TODO
+					case "provider_meta":
+						// TODO
+					default:
+						continue
+					}
+				}
+			case "provider":
+				// TODO
+			case "variable":
+				// TODO
+			case "locals":
+				// TODO
+			case "output":
+				// TODO
+			case "module":
+				call, diags := simpleDecodeModuleCallBlock(block)
+				if diags.HasErrors() {
+					return nil, diags
+				}
+				config.Module.ModuleCalls[call.Name] = call
+			case "resource":
+				resource, diags := simpleDecodeResouceBlock(block)
+				if diags.HasErrors() {
+					return nil, diags
+				}
+				config.Module.ManagedResources[fmt.Sprintf("%s.%s", resource.Type, resource.Name)] = resource
+			case "data":
+				// TODO
+			default:
+				continue
+			}
+		}
+	}
+
+	return nil, nil
+}
+
 // EvaluateExpr returns a value of the passed expression.
 // Note that there is no evaluation, no type conversion, etc.
 func (r *Runner) EvaluateExpr(expr hcl.Expression, ret interface{}) error {
@@ -505,3 +576,65 @@ func decodeProviderConfigRef(expr hcl.Expression) (*terraform.ProviderConfigRef,
 
 	return ref, nil
 }
+
+// configFileSchema is the schema for the top-level of a config file.
+// @see https://github.com/hashicorp/terraform/blob/v0.13.2/configs/parser_config.go#L197-L239
+var configFileSchema = &hcl.BodySchema{
+	Blocks: []hcl.BlockHeaderSchema{
+		{
+			Type: "terraform",
+		},
+		{
+			Type: "required_providers",
+		},
+		{
+			Type:       "provider",
+			LabelNames: []string{"name"},
+		},
+		{
+			Type:       "variable",
+			LabelNames: []string{"name"},
+		},
+		{
+			Type: "locals",
+		},
+		{
+			Type:       "output",
+			LabelNames: []string{"name"},
+		},
+		{
+			Type:       "module",
+			LabelNames: []string{"name"},
+		},
+		{
+			Type:       "resource",
+			LabelNames: []string{"type", "name"},
+		},
+		{
+			Type:       "data",
+			LabelNames: []string{"type", "name"},
+		},
+	},
+}
+
+// terraformBlockSchema is the schema for a top-level "terraform" block in a configuration file.
+// @see https://github.com/hashicorp/terraform/blob/v0.13.2/configs/parser_config.go#L241-L261
+var terraformBlockSchema = &hcl.BodySchema{
+	Attributes: []hcl.AttributeSchema{
+		{Name: "required_version"},
+		{Name: "experiments"},
+	},
+	Blocks: []hcl.BlockHeaderSchema{
+		{
+			Type:       "backend",
+			LabelNames: []string{"type"},
+		},
+		{
+			Type: "required_providers",
+		},
+		{
+			Type:       "provider_meta",
+			LabelNames: []string{"provider"},
+		},
+	},
+}

tflint/client/client.go

@@ -9,6 +9,7 @@ import (
 
 	hcl "github.com/hashicorp/hcl/v2"
 	"github.com/terraform-linters/tflint-plugin-sdk/terraform"
+	"github.com/terraform-linters/tflint-plugin-sdk/terraform/configs"
 	"github.com/terraform-linters/tflint-plugin-sdk/tflint"
 	"github.com/zclconf/go-cty/cty/gocty"
 )
@@ -150,6 +151,26 @@ func (c *Client) Backend() (*terraform.Backend, error) {
 	return backend, nil
 }
 
+// Config calls the server-side Config method and returns the Terraform configuration.
+func (c *Client) Config() (*configs.Config, error) {
+	log.Print("[DEBUG] Accessing to Config")
+
+	var response ConfigResponse
+	if err := c.rpcClient.Call("Plugin.Config", ConfigRequest{}, &response); err != nil {
+		return nil, err
+	}
+	if response.Err != nil {
+		return nil, response.Err
+	}
+
+	config, diags := decodeConfig(response.Config)
+	if diags.HasErrors() {
+		return nil, diags
+	}
+
+	return config, nil
+}
+
 // EvaluateExpr calls the server-side EvalExpr method and reflects the response
 // in the passed argument.
 func (c *Client) EvaluateExpr(expr hcl.Expression, ret interface{}) error {

tflint/client/rpc.go

@@ -58,6 +58,15 @@ type ResourcesResponse struct {
 	Err       error
 }
 
+// ConfigRequest is a request to the server-side Config method.
+type ConfigRequest struct{}
+
+// ConfigResponse is a response to the server-side Config method.
+type ConfigResponse struct {
+	Config *Config
+	Err    error
+}
+
 // EvalExprRequest is a request to the server-side EvalExpr method.
 type EvalExprRequest struct {
 	Expr      []byte

tflint/interface.go

@@ -3,6 +3,7 @@ package tflint
 import (
 	"github.com/hashicorp/hcl/v2"
 	"github.com/terraform-linters/tflint-plugin-sdk/terraform"
+	"github.com/terraform-linters/tflint-plugin-sdk/terraform/configs"
 )
 
 // Runner acts as a client for each plugin to query the host process about the Terraform configurations.
@@ -26,6 +27,10 @@ type Runner interface {
 	// Backend returns the backend configuration, if any.
 	Backend() (*terraform.Backend, error)
 
+	// Config returns the Terraform configuration.
+	// This object contains almost all accessible data structures from plugins.
+	Config() (*configs.Config, error)
+
 	// EvaluateExpr evaluates the passed expression and reflects the result in ret.
 	// Since this function returns an application error, it is expected to use the EnsureNoError
 	// to determine whether to continue processing.