Add image look up data source (fixes: #49).

.gitignore

@@ -1,4 +1,6 @@
 main
 dist/*
 packer-plugin-digitalocean
-.vscode/
+.vscode/
+docs-partials/
+docs.zip

GNUmakefile

@@ -15,7 +15,7 @@ dev: build
 	@mv ${BINARY} ~/.packer.d/plugins/${BINARY}
 
 test:
-	@go test -v -race -count $(COUNT) $(TEST) -timeout=3m
+	@go test -v -race -count $(COUNT) ./...  $(TEST) -timeout=3m
 
 install-packer-sdc: ## Install packer sofware development command
 	@go install github.com/hashicorp/packer-plugin-sdk/cmd/packer-sdc@${HASHICORP_PACKER_PLUGIN_SDK_VERSION}
@@ -28,7 +28,7 @@ plugin-check: install-packer-sdc build
 	@packer-sdc plugin-check ${BINARY}
 
 testacc: dev
-	@PACKER_ACC=1 go test -count $(COUNT) -v $(TEST) -timeout=120m
+	@PACKER_ACC=1 go test -count $(COUNT) -v ./...  $(TEST) -timeout=120m
 
 generate: install-packer-sdc
 	@go generate ./...

builder/digitalocean/builder.go

@@ -58,7 +58,7 @@ func (b *Builder) Run(ctx context.Context, ui packersdk.Ui, hook packersdk.Hook)
 		opts = append(opts, godo.SetBaseURL(b.config.APIURL))
 	}
 
-	client, err := godo.New(oauth2.NewClient(context.TODO(), &apiTokenSource{
+	client, err := godo.New(oauth2.NewClient(context.TODO(), &APITokenSource{
 		AccessToken: b.config.APIToken,
 	}), opts...)
 	if err != nil {

builder/digitalocean/builder_acc_test.go

@@ -61,7 +61,7 @@ func makeTemplateWithImageId(t *testing.T) string {
 
 		ua := useragent.String(version.PluginVersion.FormattedVersion())
 		opts := []godo.ClientOpt{godo.SetUserAgent(ua)}
-		client, err := godo.New(oauth2.NewClient(context.TODO(), &apiTokenSource{
+		client, err := godo.New(oauth2.NewClient(context.TODO(), &APITokenSource{
 			AccessToken: token,
 		}), opts...)
 		if err != nil {

builder/digitalocean/token_source.go

@@ -4,11 +4,11 @@ import (
 	"golang.org/x/oauth2"
 )
 
-type apiTokenSource struct {
+type APITokenSource struct {
 	AccessToken string
 }
 
-func (t *apiTokenSource) Token() (*oauth2.Token, error) {
+func (t *APITokenSource) Token() (*oauth2.Token, error) {
 	return &oauth2.Token{
 		AccessToken: t.AccessToken,
 	}, nil

datasource/image/data.go

@@ -0,0 +1,271 @@
+//go:generate packer-sdc mapstructure-to-hcl2 -type Config,DatasourceOutput
+//go:generate packer-sdc struct-markdown
+package image
+
+import (
+	"context"
+	"errors"
+	"fmt"
+	"log"
+	"net/url"
+	"os"
+	"regexp"
+	"sort"
+	"time"
+
+	builder "github.com/digitalocean/packer-plugin-digitalocean/builder/digitalocean"
+	"github.com/digitalocean/packer-plugin-digitalocean/version"
+
+	"github.com/digitalocean/godo"
+	"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/hashicorp/packer-plugin-sdk/useragent"
+	"github.com/zclconf/go-cty/cty"
+	"golang.org/x/oauth2"
+)
+
+var (
+	validImageTypes = []string{"application", "distribution", "user"}
+)
+
+type Config struct {
+	// The API token to used to access your account. It can also be specified via
+	// the DIGITALOCEAN_TOKEN or DIGITALOCEAN_ACCESS_TOKEN environment variables.
+	APIToken string `mapstructure:"api_token" required:"true"`
+	// A non-standard API endpoint URL. Set this if you are  using a DigitalOcean API
+	// compatible service. It can also be specified via environment variable DIGITALOCEAN_API_URL.
+	APIURL string `mapstructure:"api_url"`
+	// The name of the image to return. Only one of `name` or `name_regex` may be provided.
+	Name string `mapstructure:"name"`
+	// A regex matching the name of the image to return. Only one of `name` or `name_regex` may be provided.
+	NameRegex string `mapstructure:"name_regex"`
+	// Filter the images searched by type. This may be one of `application`, `distribution`, or `user`.
+	// By default, all image types are searched.
+	Type string `mapstructure:"type"`
+	// A DigitalOcean region slug (e.g. `nyc3`). When provided, only images available in that region
+	// will be returned.
+	Region string `mapstructure:"region"`
+	// A boolean value determining how to handle multiple matching images. By default, multiple matching images
+	// results in an error. When set to `true`, the most recently created image is returned instead.
+	Latest bool `mapstructure:"latest"`
+}
+
+type Datasource struct {
+	config Config
+}
+
+type DatasourceOutput struct {
+	// The ID of the found image.
+	ImageID int `mapstructure:"image_id"`
+	// The regions the found image is availble in.
+	ImageRegions []string `mapstructure:"image_regions"`
+}
+
+func (d *Datasource) ConfigSpec() hcldec.ObjectSpec {
+	return d.config.FlatMapstructure().HCL2Spec()
+}
+
+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.APIToken == "" {
+		d.config.APIToken = os.Getenv("DIGITALOCEAN_TOKEN")
+		if d.config.APIToken == "" {
+			d.config.APIToken = os.Getenv("DIGITALOCEAN_ACCESS_TOKEN")
+		}
+	}
+	if d.config.APIURL == "" {
+		d.config.APIURL = os.Getenv("DIGITALOCEAN_API_URL")
+	}
+
+	if d.config.APIToken == "" {
+		errs = packersdk.MultiErrorAppend(errs, errors.New("api_token is required"))
+	}
+
+	if d.config.Name == "" && d.config.NameRegex == "" {
+		errs = packersdk.MultiErrorAppend(errs, errors.New("one of name or name_regex is required"))
+	}
+
+	if d.config.Name != "" && d.config.NameRegex != "" {
+		errs = packersdk.MultiErrorAppend(errs, errors.New("only one of name or name_regex can be set"))
+	}
+
+	if d.config.Type != "" {
+		if !contains(validImageTypes, d.config.Type) {
+			errs = packersdk.MultiErrorAppend(errs, fmt.Errorf("invalid type; must be one of: %v", validImageTypes))
+		}
+	}
+
+	if errs != nil && len(errs.Errors) > 0 {
+		return errs
+	}
+
+	return nil
+}
+
+func (d *Datasource) OutputSpec() hcldec.ObjectSpec {
+	return (&DatasourceOutput{}).FlatMapstructure().HCL2Spec()
+}
+
+func (d *Datasource) Execute() (cty.Value, error) {
+	ua := useragent.String(version.PluginVersion.FormattedVersion())
+	clientOpts := []godo.ClientOpt{godo.SetUserAgent(ua)}
+	if d.config.APIURL != "" {
+		_, err := url.Parse(d.config.APIURL)
+		if err != nil {
+			return cty.NullVal(cty.EmptyObject), fmt.Errorf("invalid API URL, %s.", err)
+		}
+
+		clientOpts = append(clientOpts, godo.SetBaseURL(d.config.APIURL))
+	}
+
+	oauthClient := oauth2.NewClient(context.TODO(), &builder.APITokenSource{
+		AccessToken: d.config.APIToken,
+	})
+	client, err := godo.New(oauthClient, clientOpts...)
+	if err != nil {
+		return cty.NullVal(cty.EmptyObject), err
+	}
+
+	opts := &godo.ListOptions{
+		Page:    1,
+		PerPage: 200,
+	}
+
+	imageListFunc := client.Images.List
+	switch d.config.Type {
+	case "user":
+		imageListFunc = client.Images.ListUser
+	case "application":
+		imageListFunc = client.Images.ListApplication
+	case "distribution":
+		imageListFunc = client.Images.ListDistribution
+	}
+
+	var imageList []godo.Image
+	for {
+		images, resp, err := imageListFunc(context.Background(), opts)
+
+		if err != nil {
+			return cty.NullVal(cty.EmptyObject), err
+		}
+
+		imageList = append(imageList, images...)
+
+		if resp.Links == nil || resp.Links.IsLastPage() {
+			break
+		}
+
+		page, err := resp.Links.CurrentPage()
+		if err != nil {
+			return cty.NullVal(cty.EmptyObject), err
+		}
+
+		opts.Page = page + 1
+	}
+
+	result, err := filterImages(&d.config, imageList)
+	if err != nil {
+		return cty.NullVal(cty.EmptyObject), err
+	}
+
+	output := DatasourceOutput{
+		ImageID:      result.ID,
+		ImageRegions: result.Regions,
+	}
+
+	log.Printf("[DEBUG] found image: %v", result.ID)
+
+	return hcl2helper.HCL2ValueFromConfig(output, d.OutputSpec()), nil
+}
+
+func filterImages(c *Config, images []godo.Image) (godo.Image, error) {
+	result := make([]godo.Image, 0)
+	if c.Name != "" {
+		result = filterByName(images, c.Name)
+	}
+
+	if c.NameRegex != "" {
+		result = filterByNameRegex(images, c.NameRegex)
+	}
+
+	if c.Region != "" {
+		result = filterByRegion(result, c.Region)
+	}
+
+	if len(result) > 1 {
+		if c.Latest {
+			return findLatest(result), nil
+		}
+
+		return godo.Image{}, fmt.Errorf("More than one matching image found: %v", result)
+	}
+	if len(result) == 0 {
+		return godo.Image{}, errors.New("No image matching found")
+	}
+
+	return result[0], nil
+}
+
+func filterByName(images []godo.Image, name string) []godo.Image {
+	result := make([]godo.Image, 0)
+	for _, i := range images {
+		if i.Name == name {
+			result = append(result, i)
+		}
+	}
+
+	return result
+}
+
+func filterByNameRegex(images []godo.Image, name string) []godo.Image {
+	r := regexp.MustCompile(name)
+	result := make([]godo.Image, 0)
+	for _, i := range images {
+		if r.MatchString(i.Name) {
+			result = append(result, i)
+		}
+	}
+
+	return result
+}
+
+func filterByRegion(images []godo.Image, region string) []godo.Image {
+	result := make([]godo.Image, 0)
+	for _, i := range images {
+		for _, r := range i.Regions {
+			if r == region {
+				result = append(result, i)
+				break
+			}
+		}
+	}
+
+	return result
+}
+
+func findLatest(images []godo.Image) godo.Image {
+	sort.Slice(images, func(i, j int) bool {
+		itime, _ := time.Parse(time.RFC3339, images[i].Created)
+		jtime, _ := time.Parse(time.RFC3339, images[j].Created)
+		return itime.Unix() > jtime.Unix()
+	})
+
+	return images[0]
+}
+
+func contains(list []string, term string) bool {
+	for _, t := range list {
+		if t == term {
+			return true
+		}
+	}
+	return false
+}