use k6 cloud credentials

README.md

@@ -54,15 +54,17 @@ Since k6exec tries to emulate the `k6` command line, the `help` command or the `
 
 ### Prerequisites
 
-k6exec tries to provide the appropriate k6 executable after detecting the extension dependencies using a build service.
+k6exec tries to provide the appropriate k6 executable after detecting the extension dependencies. This can be done using a build service or a native builder.
 
 #### Build Service
 
 No additional installation is required to use the build service, just provide the build service URL.
 
 The build service URL can be specified in the `K6_BUILD_SERVICE_URL` environment variable or by using the `--build-service-url` flag.
 
-There is no default URL for the build service, otherwise k6exec will automatically provide k6 with the native builder.
+If the build service requires authentication, you can specify the authentication token using the `K6_BUILD_SERVICE_AUTH` environment variable.
+
+If the `k6_BUILD_SERVICE_URL` is not specified, `k6exec` tries to use the build service provided by Grafana Cloud K6 using the credential obtained from the [k6 cloud login](https://grafana.com/docs/grafana-cloud/testing/k6/author-run/tokens-and-cli-authentication/) command. You can also provide this credentials using the `K6_CLOUD_TOKEN` environment variable.
 
 ### Dependencies
 

cmd/context.go

@@ -2,6 +2,8 @@ package cmd
 
 import (
 	"context"
+	"fmt"
+	"strings"
 
 	"github.com/spf13/cobra"
 )
@@ -45,3 +47,24 @@ func getArgs(cmd *cobra.Command) []string {
 
 	return nil
 }
+
+// getFlagValue returns the value of the flag from the command arguments given its name and (optional) shortName.
+// If the flag is not found it returns an empty string.
+// if it is found but the next element is not its value, it returns an error.
+func getFlagValue(cmd *cobra.Command, fullName string, shortName string) (string, error) {
+	args := getArgs(cmd)
+
+	for i, arg := range args {
+		if arg == fullName || (shortName != "" && arg == shortName) {
+			// if this is the last argument or the next element is a flag, return an empty string
+			// this is an error in thc CLI arguments
+			if i+1 == len(args) || strings.HasPrefix(args[i+1], "-") {
+				return "", fmt.Errorf("flag %s is missing a value", arg)
+			}
+
+			return args[i+1], nil
+		}
+	}
+
+	return "", nil
+}

cmd/help.md

@@ -20,7 +20,9 @@ No additional installation is required to use the build service, just provide th
 
 The build service URL can be specified in the `K6_BUILD_SERVICE_URL` environment variable or by using the `--build-service-url` flag.
 
-There is no default URL for the build service, otherwise k6exec will automatically provide k6 with the native builder.
+If the build service requires authentication, you can specify the authentication token using the `K6_BUILD_SERVICE_AUTH` environment variable.
+
+If the `k6_BUILD_SERVICE_URL` is not specified, `k6exec` tries to use the build service provided by Grafana Cloud K6 using the credential obtained from the [k6 cloud login](https://grafana.com/docs/grafana-cloud/testing/k6/author-run/tokens-and-cli-authentication/) command. You can also provide this credentials using the `K6_CLOUD_TOKEN` environment variable.
 
 ### Dependencies
 

cmd/k6config.go

@@ -0,0 +1,53 @@
+package cmd
+
+import (
+	"encoding/json"
+	"errors"
+	"fmt"
+	"os"
+	"path/filepath"
+)
+
+// structure of the config file with the fields that are used by k6exec
+type k6configFile struct {
+	Collectors struct {
+		Cloud struct {
+			Token string `json:"token"`
+		} `json:"cloud"`
+	} `json:"collectors"`
+}
+
+// loadConfig loads the k6 config file from the given path or the default location.
+// if using the default location and the file does not exist, it returns an empty config.
+func loadConfig(configPath string) (k6configFile, error) {
+	var (
+		config       k6configFile
+		usingDefault bool
+		homeDir      string
+		err          error
+	)
+
+	if configPath == "" {
+		usingDefault = true
+		homeDir, err = os.UserConfigDir() //nolint:forbidigo
+		if err != nil {
+			return config, fmt.Errorf("failed to get user home directory: %w", err)
+		}
+		configPath = filepath.Join(homeDir, "loadimpact", "k6", "config.json")
+	}
+
+	buffer, err := os.ReadFile(configPath) //nolint:forbidigo,gosec
+	if err != nil {
+		if errors.Is(err, os.ErrNotExist) && usingDefault { //nolint:forbidigo
+			return config, nil
+		}
+		return config, fmt.Errorf("failed to read config file %q: %w", configPath, err)
+	}
+
+	err = json.Unmarshal(buffer, &config)
+	if err != nil {
+		return config, fmt.Errorf("failed to parse config file %q: %w", configPath, err)
+	}
+
+	return config, nil
+}

cmd/state.go

@@ -10,6 +10,10 @@ import (
 	"github.com/spf13/cobra"
 )
 
+const (
+	defaultBuildServiceURL = "https://ingest.k6.io/builder/api/v1"
+)
+
 type state struct {
 	k6exec.Options
 	buildServiceURL string
@@ -21,6 +25,7 @@ type state struct {
 	levelVar        *slog.LevelVar
 	cmd             *exec.Cmd
 	cleanup         func() error
+	configFile      string
 }
 
 func newState(levelVar *slog.LevelVar) *state {
@@ -31,11 +36,38 @@ func newState(levelVar *slog.LevelVar) *state {
 	return s
 }
 
-func (s *state) persistentPreRunE(_ *cobra.Command, _ []string) error {
+func (s *state) persistentPreRunE(cmd *cobra.Command, _ []string) error {
+	var err error
+
+	s.Options.BuildServiceURL = defaultBuildServiceURL
 	if len(s.buildServiceURL) > 0 {
 		s.Options.BuildServiceURL = s.buildServiceURL
 	}
 
+	// get authorization token for the build service
+	auth := os.Getenv("K6_CLOUD_TOKEN") //nolint:forbidigo
+
+	if len(auth) == 0 {
+		// allow overriding the config file for testing
+		configFile := s.configFile
+		if configFile == "" {
+			// check if the command has a 'config' flag and get the value
+			configFile, err = getFlagValue(cmd, "--config", "-c")
+			if err != nil {
+				return err
+			}
+		}
+
+		config, err := loadConfig(configFile)
+		if err != nil {
+			return err
+		}
+
+		auth = config.Collectors.Cloud.Token
+	}
+
+	s.Options.BuildServiceToken = auth
+
 	if s.verbose && s.levelVar != nil {
 		s.levelVar.Set(slog.LevelDebug)
 	}

cmd/state_internal_test.go

@@ -1,6 +1,7 @@
 package cmd
 
 import (
+	"context"
 	"io"
 	"log/slog"
 	"os"
@@ -9,6 +10,7 @@ import (
 
 	"github.com/grafana/k6build/pkg/testutils"
 	"github.com/grafana/k6exec"
+	"github.com/spf13/cobra"
 	"github.com/stretchr/testify/require"
 )
 
@@ -31,25 +33,52 @@ func Test_interal_state(t *testing.T) { //nolint:tparallel
 	})
 
 	t.Run("Test_persistentPreRunE", func(t *testing.T) { //nolint:paralleltest
+		cmd := &cobra.Command{}
 		st := &state{levelVar: new(slog.LevelVar)}
 
-		require.NoError(t, st.persistentPreRunE(nil, nil))
-		require.Empty(t, st.BuildServiceURL)
+		require.NoError(t, st.persistentPreRunE(cmd, nil))
+		require.Equal(t, defaultBuildServiceURL, st.BuildServiceURL)
 		require.Equal(t, slog.LevelInfo, st.levelVar.Level())
 
 		st.buildServiceURL = "http://example.com"
 
-		require.NoError(t, st.persistentPreRunE(nil, nil))
+		require.NoError(t, st.persistentPreRunE(cmd, nil))
 		require.Equal(t, "http://example.com", st.BuildServiceURL)
 
 		st.buildServiceURL = "http://example.com"
 		st.verbose = true
 
-		require.NoError(t, st.persistentPreRunE(nil, nil))
+		require.NoError(t, st.persistentPreRunE(cmd, nil))
 		require.Equal(t, slog.LevelDebug, st.levelVar.Level())
 
 		st.levelVar = nil
-		require.NoError(t, st.persistentPreRunE(nil, nil))
+		require.NoError(t, st.persistentPreRunE(cmd, nil))
+	})
+
+	t.Run("Test_loadConfig", func(t *testing.T) { //nolint:paralleltest
+		st := &state{
+			levelVar:   new(slog.LevelVar),
+			configFile: filepath.Join("testdata", "config", "valid.json"),
+		}
+
+		require.NoError(t, st.persistentPreRunE(&cobra.Command{}, nil))
+		require.Equal(t, "token", st.Options.BuildServiceToken)
+
+		st = &state{
+			levelVar:   new(slog.LevelVar),
+			configFile: filepath.Join("testdata", "config", "empty.json"),
+		}
+
+		require.NoError(t, st.persistentPreRunE(&cobra.Command{}, nil))
+		require.Empty(t, st.Options.BuildServiceToken)
+
+		// test config override from flag
+		cmd := &cobra.Command{Use: "test"}
+		cmd.SetContext(context.WithValue(context.Background(), argsKey{}, []string{"test", "--config", "no_such_file.json"}))
+		st = &state{
+			levelVar: new(slog.LevelVar),
+		}
+		require.Error(t, st.persistentPreRunE(cmd, nil))
 	})
 
 	t.Run("Test_preRunE", func(t *testing.T) { //nolint:paralleltest

cmd/testdata/config/empty.json

@@ -0,0 +1 @@
+{}

cmd/testdata/config/valid.json

@@ -0,0 +1,7 @@
+{
+  "collectors": {
+    "cloud": {
+      "token": "token"
+    }
+  }
+}

options.go

@@ -30,4 +30,7 @@ type Options struct {
 	// BuildServiceURL contains the URL of the k6 build service to be used.
 	// If the value is not nil, the k6 binary is built using the build service instead of the local build.
 	BuildServiceURL string
+	// BuildServiceToken contains the token to be used to authenticate with the build service.
+	// Defaults to K6_CLOUD_TOKEN environment variable is set, or the value stored in the k6 config file.
+	BuildServiceToken string
 }

provision.go

@@ -12,6 +12,7 @@ func provision(ctx context.Context, deps k6deps.Dependencies, opts *Options) (st
 
 	if opts != nil {
 		config.BuildServiceURL = opts.BuildServiceURL
+		config.BuildServiceAuth = opts.BuildServiceToken
 	}
 
 	provider, err := k6provider.NewProvider(config)