Extract config logic into own package

go.mod

@@ -25,6 +25,7 @@ require (
 	github.com/stretchr/testify v1.8.2
 	github.com/tidwall/pretty v1.2.1
 	github.com/zalando/go-keyring v0.2.2
+	golang.org/x/exp v0.0.0-20230321023759-10a507213a29
 	golang.org/x/oauth2 v0.7.0
 	golang.org/x/sync v0.1.0
 	golang.org/x/sys v0.7.0

go.sum

@@ -190,6 +190,8 @@ golang.org/x/crypto v0.0.0-20191011191535-87dc89f01550/go.mod h1:yigFU9vqHzYiE8U
 golang.org/x/crypto v0.0.0-20220427172511-eb4f295cb31f/go.mod h1:IxCIyHEi3zRg3s0A5j5BB6A9Jmi73HwBIUl50j+osU4=
 golang.org/x/crypto v0.7.0 h1:AvwMYaRytfdeVt3u6mLaxYtErKYjxA2OXjJ1HHq6t3A=
 golang.org/x/crypto v0.7.0/go.mod h1:pYwdfH91IfpZVANVyUOhSIPZaFoJGxTFbZhFTx+dXZU=
+golang.org/x/exp v0.0.0-20230321023759-10a507213a29 h1:ooxPy7fPvB4kwsA2h+iBNHkAbp/4JxTSwCmvdjEYmug=
+golang.org/x/exp v0.0.0-20230321023759-10a507213a29/go.mod h1:CxIveKay+FTh1D0yPZemJVgC/95VzuuOLq5Qi4xnoYc=
 golang.org/x/mod v0.4.2/go.mod h1:s0Qsj1ACt9ePp/hMypM3fl4fZqREWJwdYDEqhRiZZUA=
 golang.org/x/mod v0.8.0 h1:LUYupSeNrTNCGzR/hVBk2NHZO4hXcVaW1k4Qx7rjPx8=
 golang.org/x/mod v0.8.0/go.mod h1:iBbtSCu2XBx23ZKBPSOrRkjjQPZFPuis4dIYUhu/chs=

internal/config/config.go

@@ -0,0 +1,252 @@
+package config
+
+import (
+	"encoding/json"
+	"errors"
+	"fmt"
+	"os"
+	"path"
+	"path/filepath"
+	"sync"
+
+	"github.com/google/uuid"
+	"github.com/lestrrat-go/jwx/jwt"
+)
+
+// ErrConfigFileMissing is thrown when the config.json file is missing.
+var ErrConfigFileMissing = errors.New("config.json file is missing")
+
+// ErrNoAuthenticatedTenants is thrown when the config file has no authenticated tenants.
+var ErrNoAuthenticatedTenants = errors.New("Not logged in. Try `auth0 login`.")
+
+// Config holds cli configuration settings.
+type Config struct {
+	onlyOnce  sync.Once
+	initError error
+
+	Path string `json:"-"`
+
+	InstallID     string  `json:"install_id,omitempty"`
+	DefaultTenant string  `json:"default_tenant"`
+	Tenants       Tenants `json:"tenants"`
+}
+
+// Initialize will load the config settings into memory.
+func (c *Config) Initialize() error {
+	c.onlyOnce.Do(func() {
+		c.initError = c.loadFromDisk()
+	})
+
+	return c.initError
+}
+
+// VerifyAuthentication checks to see if the config is not corrupted,
+// and we have an authenticated tenant saved.
+// If we have at least one tenant saved but the DefaultTenant
+// is empty, it will attempt to set the first available
+// tenant as the DefaultTenant and save to disk.
+func (c *Config) VerifyAuthentication() error {
+	if err := c.Initialize(); err != nil {
+		return err
+	}
+
+	if len(c.Tenants) == 0 {
+		return ErrNoAuthenticatedTenants
+	}
+
+	if c.DefaultTenant != "" {
+		return nil
+	}
+
+	for tenant := range c.Tenants {
+		c.DefaultTenant = tenant
+		break // Pick first tenant and exit.
+	}
+
+	return c.saveToDisk()
+}
+
+// IsLoggedInWithTenant checks if we're logged in with the given tenant.
+func (c *Config) IsLoggedInWithTenant(tenantName string) bool {
+	// Ignore error as we could
+	// be not logged in yet.
+	_ = c.Initialize()
+
+	if tenantName == "" {
+		tenantName = c.DefaultTenant
+	}
+
+	tenant, ok := c.Tenants[tenantName]
+	if !ok {
+		return false
+	}
+
+	token, err := jwt.ParseString(tenant.GetAccessToken())
+	if err != nil {
+		return false
+	}
+
+	if err = jwt.Validate(token, jwt.WithIssuer("https://auth0.auth0.com/")); err != nil {
+		return false
+	}
+
+	return true
+}
+
+// GetTenant retrieves all the tenant information from the config.
+func (c *Config) GetTenant(tenantName string) (Tenant, error) {
+	if err := c.Initialize(); err != nil {
+		return Tenant{}, err
+	}
+
+	tenant, ok := c.Tenants[tenantName]
+	if !ok {
+		return Tenant{}, fmt.Errorf(
+			"failed to find tenant: %s. Run 'auth0 tenants use' to see your configured tenants "+
+				"or run 'auth0 login' to configure a new tenant",
+			tenantName,
+		)
+	}
+
+	return tenant, nil
+}
+
+// AddTenant adds a tenant to the config.
+// This is called after a login has completed.
+func (c *Config) AddTenant(tenant Tenant) error {
+	// Ignore error as we could be
+	// logging in the first time.
+	_ = c.Initialize()
+
+	c.ensureInstallIDAssigned()
+
+	if c.DefaultTenant == "" {
+		c.DefaultTenant = tenant.Domain
+	}
+
+	if c.Tenants == nil {
+		c.Tenants = make(map[string]Tenant)
+	}
+
+	c.Tenants[tenant.Domain] = tenant
+
+	return c.saveToDisk()
+}
+
+// RemoveTenant removes a tenant from the config.
+// This is called after a logout has completed.
+func (c *Config) RemoveTenant(tenant string) error {
+	if err := c.Initialize(); err != nil {
+		if errors.Is(err, ErrConfigFileMissing) {
+			return nil // Config file is missing, so nothing to remove.
+		}
+		return err
+	}
+
+	if c.DefaultTenant == "" && len(c.Tenants) == 0 {
+		return nil // Nothing to remove.
+	}
+
+	if c.DefaultTenant != "" && len(c.Tenants) == 0 {
+		c.DefaultTenant = "" // Reset possible corruption of config file.
+		return c.saveToDisk()
+	}
+
+	delete(c.Tenants, tenant)
+
+	if c.DefaultTenant == tenant {
+		c.DefaultTenant = ""
+
+		for otherTenant := range c.Tenants {
+			c.DefaultTenant = otherTenant
+			break // Pick first tenant and exit as we called delete above.
+		}
+	}
+
+	return c.saveToDisk()
+}
+
+// ListAllTenants retrieves a list with all configured tenants.
+func (c *Config) ListAllTenants() ([]Tenant, error) {
+	if err := c.Initialize(); err != nil {
+		return nil, err
+	}
+
+	tenants := make([]Tenant, 0, len(c.Tenants))
+	for _, tenant := range c.Tenants {
+		tenants = append(tenants, tenant)
+	}
+
+	return tenants, nil
+}
+
+// SaveNewDefaultTenant saves the new default tenant to the disk.
+func (c *Config) SaveNewDefaultTenant(tenant string) error {
+	if err := c.Initialize(); err != nil {
+		return err
+	}
+
+	c.DefaultTenant = tenant
+
+	return c.saveToDisk()
+}
+
+// SaveNewDefaultAppIDForTenant saves the new default app id for the tenant to the disk.
+func (c *Config) SaveNewDefaultAppIDForTenant(tenantName, appID string) error {
+	tenant, err := c.GetTenant(tenantName)
+	if err != nil {
+		return err
+	}
+
+	tenant.DefaultAppID = appID
+	c.Tenants[tenant.Domain] = tenant
+
+	return c.saveToDisk()
+}
+
+func (c *Config) ensureInstallIDAssigned() {
+	if c.InstallID != "" {
+		return
+	}
+
+	c.InstallID = uuid.NewString()
+}
+
+func (c *Config) loadFromDisk() error {
+	if c.Path == "" {
+		c.Path = defaultPath()
+	}
+
+	if _, err := os.Stat(c.Path); os.IsNotExist(err) {
+		return ErrConfigFileMissing
+	}
+
+	buffer, err := os.ReadFile(c.Path)
+	if err != nil {
+		return err
+	}
+
+	return json.Unmarshal(buffer, c)
+}
+
+func (c *Config) saveToDisk() error {
+	dir := filepath.Dir(c.Path)
+	if _, err := os.Stat(dir); os.IsNotExist(err) {
+		const dirPerm os.FileMode = 0700 // Directory permissions (read, write, and execute for the owner only).
+		if err := os.MkdirAll(dir, dirPerm); err != nil {
+			return err
+		}
+	}
+
+	buffer, err := json.MarshalIndent(c, "", "    ")
+	if err != nil {
+		return err
+	}
+
+	const filePerm os.FileMode = 0600 // File permissions (read and write for the owner only).
+	return os.WriteFile(c.Path, buffer, filePerm)
+}
+
+func defaultPath() string {
+	return path.Join(os.Getenv("HOME"), ".config", "auth0", "config.json")
+}