Merge pull request #299 from dhavalbhensdadiya-crest/parametermanager

Adding support of Parametermanager in Google Compute Integration

Author: tanmay-hc

.web-docs/components/data-source/parametermanager/README.md

@@ -0,0 +1,70 @@
+The Parameter Manager data source provides the capability to retrieve the parameters stored in google cloud along with revealed secrets
+
+-> **Note:** Data sources is a feature exclusively available to HCL2 templates.
+
+Basic examples of usage:
+
+```hcl
+data "googlecompute-parametermanager" "basic-example" {
+  project_id = "debian-cloud"
+  name       = "packer_test_parameter"
+  key        = "packer_test_key"
+  version    = "1"
+  location   = "us-east1"    
+}
+
+# usage example of the data source output
+locals {
+  value = data.googlecompute-parametermanager.basic-example.value
+  payload = data.googlecompute-parametermanager.basic-example.payload
+}
+```
+
+Reading key-value pairs from JSON back into a native Packer map can be accomplished
+with the [jsondecode() function](/packer/docs/templates/hcl_templates/functions/encoding/jsondecode).
+
+Reading key-value pairs from YAML back into a native Packer map can be accomplished
+with the [yamldecode() function](/packer/docs/templates/hcl_templates/functions/encoding/yamldecode).
+
+## Configuration Reference
+
+### Required
+
+<!-- Code generated from the comments of the Config struct in datasource/parametermanager/data.go; DO NOT EDIT MANUALLY -->
+
+- `project_id` (string) - The Google Cloud project ID where the parameter is stored.
+
+- `name` (string) - The name of the parameter within the Parameter Manager.
+
+- `version` (string) - The version of the parameter within the Parameter Manager.
+
+<!-- End of code generated from the comments of the Config struct in datasource/parametermanager/data.go; -->
+
+
+### Optional
+
+<!-- Code generated from the comments of the Config struct in datasource/parametermanager/data.go; DO NOT EDIT MANUALLY -->
+
+- `location` (string) - The location in which parameter is stored. Defaults to "global" if not specified.
+
+- `key` (string) - A specific key to extract from the parameter payload if it's a JSON or YAML object.
+
+<!-- End of code generated from the comments of the Config struct in datasource/parametermanager/data.go; -->
+
+
+## Output Data
+
+<!-- Code generated from the comments of the DatasourceOutput struct in datasource/parametermanager/data.go; DO NOT EDIT MANUALLY -->
+
+- `payload` (string) - The raw string payload of the parameter version.
+
+- `value` (string) - The value extracted using the 'key', if provided.
+
+<!-- End of code generated from the comments of the DatasourceOutput struct in datasource/parametermanager/data.go; -->
+
+
+## Authentication
+
+To authenticate with GCE, this data-source supports everything the plugin does.
+To get more information on this, refer to the plugin's description page, under
+the [authentication](/packer/integrations/hashicorp/googlecompute#authentication) section.

.web-docs/metadata.hcl

@@ -13,6 +13,11 @@ integration {
     name = "Secrets Manager"
     slug = "secretsmanager"
   }
+  component {
+    type = "data-source"
+    name = "Parameter Manager"
+    slug = "parametermanager"
+  }
   component {
     type = "data-source"
     name = "GCE Image"

datasource/parametermanager/data.go

@@ -0,0 +1,191 @@
+//go:generate packer-sdc struct-markdown
+//go:generate packer-sdc mapstructure-to-hcl2 -type Config,DatasourceOutput
+
+package parametermanager
+
+import (
+	"context"
+	"encoding/json"
+	"errors"
+	"fmt"
+
+	"github.com/hashicorp/hcl/v2/hcldec"
+	"github.com/hashicorp/packer-plugin-sdk/hcl2helper"
+	packersdk "github.com/hashicorp/packer-plugin-sdk/packer"
+	"github.com/hashicorp/packer-plugin-sdk/template/config"
+	"github.com/stretchr/testify/assert/yaml"
+
+	"github.com/zclconf/go-cty/cty"
+
+	parametermanager "cloud.google.com/go/parametermanager/apiv1"
+	parametermanagerpb "cloud.google.com/go/parametermanager/apiv1/parametermanagerpb"
+
+	"google.golang.org/api/option"
+	"google.golang.org/grpc/codes"
+	"google.golang.org/grpc/status"
+)
+
+// Config is the configuration structure for the data source.
+type Config struct {
+	// The Google Cloud project ID where the parameter is stored.
+	ProjectId string `mapstructure:"project_id" required:"true"`
+
+	// The location in which parameter is stored. Defaults to "global" if not specified.
+	Location string `mapstructure:"location"`
+
+	// The name of the parameter within the Parameter Manager.
+	Name string `mapstructure:"name" required:"true"`
+
+	// The version of the parameter within the Parameter Manager.
+	Version string `mapstructure:"version" required:"true"`
+
+	// A specific key to extract from the parameter payload if it's a JSON or YAML object.
+	Key string `mapstructure:"key"`
+}
+
+// Datasource is the data source implementation.
+type Datasource struct {
+	config Config
+}
+
+// DatasourceOutput contains the data returned by the data source.
+type DatasourceOutput struct {
+	// The raw string payload of the parameter version.
+	Payload string `mapstructure:"payload"`
+
+	// The value extracted using the 'key', if provided.
+	Value string `mapstructure:"value"`
+}
+
+// ConfigSpec returns the HCL object spec for the data source configuration.
+func (d *Datasource) ConfigSpec() hcldec.ObjectSpec {
+	return d.config.FlatMapstructure().HCL2Spec()
+}
+
+// OutputSpec returns the HCL object spec for the data source output.
+func (d *Datasource) OutputSpec() hcldec.ObjectSpec {
+	return (&DatasourceOutput{}).FlatMapstructure().HCL2Spec()
+}
+
+// Configure sets up the data source configuration.
+func (d *Datasource) Configure(raws ...interface{}) error {
+	err := config.Decode(&d.config, nil, raws...)
+	if err != nil {
+		return err
+	}
+
+	var errs *packersdk.MultiError
+
+	if d.config.ProjectId == "" {
+		errs = packersdk.MultiErrorAppend(errs, errors.New("a 'project_id' must be specified"))
+	}
+
+	if d.config.Location == "" {
+		d.config.Location = "global"
+	}
+
+	if d.config.Name == "" {
+		errs = packersdk.MultiErrorAppend(errs, errors.New("a 'name' must be specified"))
+	}
+
+	if d.config.Version == "" {
+		errs = packersdk.MultiErrorAppend(errs, errors.New("a 'version' must be specified"))
+	}
+
+	if errs != nil && len(errs.Errors) > 0 {
+		return errs
+	}
+
+	return nil
+}
+
+// Execute fetches the parameter from Google Cloud Parameter Manager.
+func (d *Datasource) Execute() (cty.Value, error) {
+	ctx := context.Background()
+
+	// Create a client
+	var client *parametermanager.Client
+	var err error
+
+	if d.config.Location == "global" {
+		client, err = parametermanager.NewClient(ctx)
+	} else {
+		endpoint := fmt.Sprintf("parametermanager.%s.rep.googleapis.com:443", d.config.Location)
+		client, err = parametermanager.NewClient(ctx, option.WithEndpoint(endpoint))
+	}
+
+	if err != nil {
+		return cty.NullVal(cty.EmptyObject), fmt.Errorf("failed to create parameter manager client: %w", err)
+	}
+	defer client.Close()
+
+	// Build the request to get parameter format
+	parameterFormatURL := fmt.Sprintf("projects/%s/locations/%s/parameters/%s", d.config.ProjectId, d.config.Location, d.config.Name)
+
+	// Build the request to get parameter format
+	parameterFormatReq := &parametermanagerpb.GetParameterRequest{
+		Name: parameterFormatURL,
+	}
+
+	// Call the API to get parameter.
+	paramFormatResp, err := client.GetParameter(ctx, parameterFormatReq)
+	if err != nil {
+		return cty.NullVal(cty.EmptyObject), fmt.Errorf("failed to identify parameter format %w", err)
+	}
+
+	paramFormat := paramFormatResp.Format
+
+	parameterPayloadURL := fmt.Sprintf("projects/%s/locations/%s/parameters/%s/versions/%s", d.config.ProjectId, d.config.Location, d.config.Name, d.config.Version)
+
+	// Build the request to get parameter payload
+	parameterPayloadReq := &parametermanagerpb.RenderParameterVersionRequest{
+		Name: parameterPayloadURL,
+	}
+
+	// Call the API to render a parameter version.
+	parameterPayloadResp, err := client.RenderParameterVersion(ctx, parameterPayloadReq)
+	if err != nil {
+		st := status.Convert(err)
+		if st.Code() == codes.NotFound {
+			return cty.NullVal(cty.EmptyObject), fmt.Errorf("value %q not found", parameterPayloadResp)
+		}
+		return cty.NullVal(cty.EmptyObject), fmt.Errorf("error rendering parameter: %w", err)
+	}
+
+	payload := parameterPayloadResp.RenderedPayload
+
+	// Extract value from payload if key is provided
+	var value string
+	var payloadMap map[string]interface{}
+	if d.config.Key != "" {
+		switch paramFormat {
+		case parametermanagerpb.ParameterFormat_JSON:
+			jsonErr := json.Unmarshal(payload, &payloadMap)
+			if jsonErr != nil {
+				return cty.NullVal(cty.EmptyObject), fmt.Errorf("error unmarshaling JSON payload: %w", jsonErr)
+			}
+
+		case parametermanagerpb.ParameterFormat_YAML:
+			yamlErr := yaml.Unmarshal(payload, &payloadMap)
+			if yamlErr != nil {
+				return cty.NullVal(cty.EmptyObject), fmt.Errorf("error unmarshaling YAML payload: %w", yamlErr)
+			}
+
+		default:
+			return cty.NullVal(cty.EmptyObject), fmt.Errorf("key extraction is supported only for JSON and YAML payload")
+		}
+
+		val, ok := payloadMap[d.config.Key]
+		if !ok {
+			return cty.NullVal(cty.EmptyObject), fmt.Errorf("key %q not found in payload", d.config.Key)
+		}
+		value = fmt.Sprintf("%v", val)
+	}
+
+	output := DatasourceOutput{
+		Payload: string(payload),
+		Value:   value,
+	}
+
+	return hcl2helper.HCL2ValueFromConfig(output, d.OutputSpec()), nil
+}