feat(dns): add CLI commands to reserve, show, delete cluster domain

cmd/uncloud/dns/release.go

@@ -0,0 +1,54 @@
+package dns
+
+import (
+	"context"
+	"errors"
+	"fmt"
+	"github.com/spf13/cobra"
+	"google.golang.org/grpc/codes"
+	"google.golang.org/grpc/status"
+	"google.golang.org/protobuf/types/known/emptypb"
+	"uncloud/internal/cli"
+)
+
+type releaseOptions struct {
+	cluster string
+}
+
+func NewReleaseCommand() *cobra.Command {
+	opts := releaseOptions{}
+
+	cmd := &cobra.Command{
+		Use:   "release",
+		Short: "Release the reserved cluster domain.",
+		RunE: func(cmd *cobra.Command, args []string) error {
+			uncli := cmd.Context().Value("cli").(*cli.CLI)
+			return release(cmd.Context(), uncli, opts)
+		},
+	}
+
+	cmd.Flags().StringVarP(
+		&opts.cluster, "cluster", "c", "",
+		"Name of the cluster. (default is the current cluster)",
+	)
+
+	return cmd
+}
+
+func release(ctx context.Context, uncli *cli.CLI, opts releaseOptions) error {
+	client, err := uncli.ConnectCluster(ctx, opts.cluster)
+	if err != nil {
+		return fmt.Errorf("connect to cluster: %w", err)
+	}
+	defer client.Close()
+
+	domain, err := client.ReleaseDomain(ctx, &emptypb.Empty{})
+	if err != nil {
+		if status.Convert(err).Code() == codes.NotFound {
+			return errors.New("no domain reserved")
+		}
+	}
+
+	fmt.Printf("Released cluster domain: %s\n", domain.Name)
+	return nil
+}

cmd/uncloud/dns/reserve.go

@@ -0,0 +1,62 @@
+package dns
+
+import (
+	"context"
+	"errors"
+	"fmt"
+	"github.com/spf13/cobra"
+	"google.golang.org/grpc/codes"
+	"google.golang.org/grpc/status"
+	"uncloud/internal/cli"
+	"uncloud/internal/machine/api/pb"
+)
+
+const DefaultUncloudDNSAPIEndpoint = "https://dns.uncloud.run/v1"
+
+type reserveOptions struct {
+	endpoint string
+	cluster  string
+}
+
+func NewReserveCommand() *cobra.Command {
+	opts := reserveOptions{}
+
+	cmd := &cobra.Command{
+		Use:   "reserve",
+		Short: "Reserve a cluster domain in Uncloud DNS.",
+		RunE: func(cmd *cobra.Command, args []string) error {
+			uncli := cmd.Context().Value("cli").(*cli.CLI)
+			return reserve(cmd.Context(), uncli, opts)
+		},
+	}
+
+	cmd.Flags().StringVar(&opts.endpoint, "endpoint", DefaultUncloudDNSAPIEndpoint,
+		"API endpoint for the Uncloud DNS service.")
+	cmd.Flags().StringVarP(
+		&opts.cluster, "cluster", "c", "",
+		"Name of the cluster. (default is the current cluster)",
+	)
+
+	return cmd
+}
+
+func reserve(ctx context.Context, uncli *cli.CLI, opts reserveOptions) error {
+	client, err := uncli.ConnectCluster(ctx, opts.cluster)
+	if err != nil {
+		return fmt.Errorf("connect to cluster: %w", err)
+	}
+	defer client.Close()
+
+	domain, err := client.ReserveDomain(ctx, &pb.ReserveDomainRequest{ApiEndpoint: opts.endpoint})
+	if err != nil {
+		if status.Convert(err).Code() == codes.AlreadyExists {
+			return errors.New("domain already reserved")
+		}
+		return err
+	}
+
+	fmt.Printf("Reserved cluster domain: %s\n", domain.Name)
+	fmt.Println("Redeploy the Caddy service ('uc caddy deploy') to configure DNS records for the domain " +
+		"to route traffic to the services in the cluster.")
+	return nil
+}

cmd/uncloud/dns/root.go

@@ -0,0 +1,22 @@
+package dns
+
+import (
+	"github.com/spf13/cobra"
+)
+
+func NewRootCommand() *cobra.Command {
+	cmd := &cobra.Command{
+		Use:   "dns",
+		Short: "Manage cluster domain in Uncloud DNS.",
+		Long: "Manage cluster domain in Uncloud DNS.\n" +
+			"DNS commands allow you to reserve or release a unique '<id>.cluster.uncloud.run' domain for your " +
+			"cluster. When reserved, Caddy service deployments will automatically update DNS records to route " +
+			"traffic to the services in the cluster.",
+	}
+	cmd.AddCommand(
+		NewReleaseCommand(),
+		NewReserveCommand(),
+		NewShowCommand(),
+	)
+	return cmd
+}

cmd/uncloud/dns/show.go

@@ -0,0 +1,55 @@
+package dns
+
+import (
+	"context"
+	"errors"
+	"fmt"
+	"github.com/spf13/cobra"
+	"google.golang.org/grpc/codes"
+	"google.golang.org/grpc/status"
+	"google.golang.org/protobuf/types/known/emptypb"
+	"uncloud/internal/cli"
+)
+
+type showOptions struct {
+	cluster string
+}
+
+func NewShowCommand() *cobra.Command {
+	opts := showOptions{}
+
+	cmd := &cobra.Command{
+		Use:   "show",
+		Short: "Print the cluster domain name.",
+		RunE: func(cmd *cobra.Command, args []string) error {
+			uncli := cmd.Context().Value("cli").(*cli.CLI)
+			return show(cmd.Context(), uncli, opts)
+		},
+	}
+
+	cmd.Flags().StringVarP(
+		&opts.cluster, "cluster", "c", "",
+		"Name of the cluster. (default is the current cluster)",
+	)
+
+	return cmd
+}
+
+func show(ctx context.Context, uncli *cli.CLI, opts showOptions) error {
+	client, err := uncli.ConnectCluster(ctx, opts.cluster)
+	if err != nil {
+		return fmt.Errorf("connect to cluster: %w", err)
+	}
+	defer client.Close()
+
+	domain, err := client.GetDomain(ctx, &emptypb.Empty{})
+	if err != nil {
+		if status.Convert(err).Code() == codes.NotFound {
+			return errors.New("no domain reserved")
+		}
+		return err
+	}
+
+	fmt.Println(domain.Name)
+	return nil
+}

cmd/uncloud/main.go

@@ -7,6 +7,7 @@ import (
 	"os"
 	"strings"
 	"uncloud/cmd/uncloud/caddy"
+	"uncloud/cmd/uncloud/dns"
 	"uncloud/cmd/uncloud/machine"
 	"uncloud/cmd/uncloud/service"
 	"uncloud/internal/cli"
@@ -43,6 +44,7 @@ func main() {
 
 	cmd.AddCommand(
 		caddy.NewRootCommand(),
+		dns.NewRootCommand(),
 		machine.NewRootCommand(),
 		service.NewRootCommand(),
 		service.NewInspectCommand(),

internal/dns/api.go

@@ -0,0 +1,16 @@
+package dns
+
+type DomainResponse struct {
+	Name  string `json:"name,omitempty"`
+	Token string `json:"token,omitempty"`
+}
+
+type AuthErrorResponse struct {
+	Status  int           `json:"status,omitempty"`
+	Message string        `json:"msg,omitempty"`
+	Data    authErrorData `json:"data,omitempty"`
+}
+
+type authErrorData struct {
+	NoDomain bool `json:"noDomain,omitempty"`
+}

internal/dns/client.go

@@ -0,0 +1,118 @@
+package dns
+
+import (
+	"encoding/json"
+	"errors"
+	"fmt"
+	"io"
+	"log/slog"
+	"net/http"
+	"strings"
+)
+
+// The dns package code is based on https://github.com/acorn-io/runtime/blob/main/pkg/dns.
+
+// Client handles interactions with the Uncloud DNS API service.
+type Client interface {
+	// ReserveDomain calls Uncloud DNS to reserve a new domain. It returns the domain, a token for authentication,
+	// and an error.
+	ReserveDomain(endpoint string) (string, string, error)
+}
+
+// ErrAuthNoDomain indicates that a request failed authentication because the domain was not found.
+// If encountered, a new domain needs to be reserved.
+var ErrAuthNoDomain = errors.New("the supplied domain failed authentication")
+
+// NewClient creates a new AcornDNS client
+func NewClient() Client {
+	return &client{
+		c: http.DefaultClient,
+	}
+}
+
+type client struct {
+	c *http.Client
+}
+
+func (c *client) ReserveDomain(endpoint string) (string, string, error) {
+	url := fmt.Sprintf("%s/%s", endpoint, "domains")
+
+	req, err := c.request(http.MethodPost, url, nil, "")
+	if err != nil {
+		return "", "", err
+	}
+
+	resp := &DomainResponse{}
+	err = c.do(req, resp)
+	if err != nil {
+		return "", "", err
+	}
+
+	domain := resp.Name
+	if strings.HasPrefix(domain, ".") {
+		domain = domain[1:]
+	}
+	return domain, resp.Token, nil
+}
+
+func (c *client) request(method string, url string, body io.Reader, token string) (*http.Request, error) {
+	req, err := http.NewRequest(method, url, body)
+	if err != nil {
+		return nil, err
+	}
+	req.Header.Add("Content-Type", "application/json")
+
+	if token != "" {
+		bearer := "Bearer " + token
+		req.Header.Add("Authorization", bearer)
+	}
+
+	return req, nil
+}
+
+func (c *client) do(req *http.Request, responseBody any) error {
+	slog.Debug("Making request to DNS service.", "method", req.Method, "url", req.URL)
+
+	resp, err := c.c.Do(req)
+	if err != nil {
+		return err
+	}
+
+	slog.Debug("Response code for request to DNS service.",
+		"method", req.Method, "url", req.URL, "code", resp.StatusCode)
+	// When err is nil, resp contains a non-nil resp.Body which must be closed.
+	defer resp.Body.Close()
+
+	body, err := io.ReadAll(resp.Body)
+	if err != nil {
+		return fmt.Errorf("read response body: %w", err)
+	}
+
+	if resp.StatusCode == http.StatusUnauthorized {
+		var authError AuthErrorResponse
+
+		err = json.Unmarshal(body, &authError)
+		if err != nil {
+			return fmt.Errorf("unmarshal auth error response: %w", err)
+		}
+
+		if authError.Data.NoDomain {
+			return ErrAuthNoDomain
+		}
+
+		return errors.New("authentication failed")
+	}
+
+	if code := resp.StatusCode; code < 200 || code > 300 {
+		return fmt.Errorf("unexpected response status code: %d", code)
+	}
+
+	if responseBody != nil {
+		err = json.Unmarshal(body, responseBody)
+		if err != nil {
+			return fmt.Errorf("unmarshal response body (%s): %w", string(body), err)
+		}
+	}
+
+	return nil
+}