Add new Client API

Signed-off-by: Helder Correia <174525+helderco@users.noreply.github.com>

plan/task/clientcommand.go

@@ -0,0 +1,165 @@
+package task
+
+import (
+	"context"
+	"errors"
+	"fmt"
+	"io"
+	"os"
+	"os/exec"
+	"strings"
+
+	"cuelang.org/go/cue"
+	"github.com/rs/zerolog/log"
+	"go.dagger.io/dagger/compiler"
+	"go.dagger.io/dagger/plancontext"
+	"go.dagger.io/dagger/solver"
+)
+
+func init() {
+	Register("ClientCommand", func() Task { return &clientCommandTask{} })
+}
+
+type clientCommandTask struct {
+}
+
+func (t clientCommandTask) Run(ctx context.Context, pctx *plancontext.Context, s solver.Solver, v *compiler.Value) (*compiler.Value, error) {
+	var opts struct {
+		Name string
+		Args []string
+	}
+
+	if err := v.Decode(&opts); err != nil {
+		return nil, err
+	}
+
+	flags, err := v.Lookup("flags").Fields()
+	if err != nil {
+		return nil, err
+	}
+
+	var flagArgs []string
+	for _, flag := range flags {
+		switch flag.Value.Kind() {
+		case cue.BoolKind:
+			if b, _ := flag.Value.Bool(); b {
+				flagArgs = append(flagArgs, flag.Label())
+			}
+		case cue.StringKind:
+			if s, _ := flag.Value.String(); s != "" {
+				flagArgs = append(flagArgs, flag.Label(), s)
+			}
+		}
+	}
+	opts.Args = append(flagArgs, opts.Args...)
+
+	envs, err := v.Lookup("env").Fields()
+	if err != nil {
+		return nil, err
+	}
+
+	env := make([]string, len(envs))
+	for _, envvar := range envs {
+		s, err := t.getString(pctx, envvar.Value)
+		if err != nil {
+			return nil, err
+		}
+		env = append(env, fmt.Sprintf("%s=%s", envvar.Label(), s))
+	}
+
+	lg := log.Ctx(ctx)
+	lg.Debug().Str("name", opts.Name).Str("args", strings.Join(opts.Args, " ")).Msg("running client command")
+
+	cmd := exec.CommandContext(ctx, opts.Name, opts.Args...) //#nosec G204
+	cmd.Env = append(os.Environ(), env...)
+
+	if i := v.Lookup("stdin"); i.Exists() {
+		val, err := t.getString(pctx, i)
+		if err != nil {
+			return nil, err
+		}
+
+		stdin, err := cmd.StdinPipe()
+		if err != nil {
+			return nil, err
+		}
+
+		go func() {
+			defer stdin.Close()
+			io.WriteString(stdin, val)
+		}()
+	}
+
+	stdout, err := cmd.StdoutPipe()
+	if err != nil {
+		return nil, err
+	}
+
+	stderr, err := cmd.StderrPipe()
+	if err != nil {
+		return nil, err
+	}
+
+	if err := cmd.Start(); err != nil {
+		return nil, err
+	}
+
+	stdoutVal, err := t.readPipe(&stdout, pctx, v.Lookup("stdout"))
+	if err != nil {
+		return nil, err
+	}
+
+	stderrVal, err := t.readPipe(&stderr, pctx, v.Lookup("stderr"))
+	if err != nil {
+		return nil, err
+	}
+
+	if err := cmd.Wait(); err != nil {
+		var exitErr *exec.ExitError
+		if errors.As(err, &exitErr) {
+			// FIXME: stderr may be requested as a secret
+			lg.Err(err).Msg(string(exitErr.Stderr))
+		}
+		return nil, err
+	}
+
+	return compiler.NewValue().FillFields(map[string]interface{}{
+		"stdout": stdoutVal,
+		"stderr": stderrVal,
+	})
+}
+
+func (t clientCommandTask) getString(pctx *plancontext.Context, v *compiler.Value) (string, error) {
+	if plancontext.IsSecretValue(v) {
+		secret, err := pctx.Secrets.FromValue(v)
+		if err != nil {
+			return "", err
+		}
+		return secret.PlainText(), nil
+	}
+
+	s, err := v.String()
+	if err != nil {
+		return "", err
+	}
+
+	return s, nil
+}
+
+func (t clientCommandTask) readPipe(pipe *io.ReadCloser, pctx *plancontext.Context, v *compiler.Value) (*compiler.Value, error) {
+	slurp, err := io.ReadAll(*pipe)
+	if err != nil {
+		return nil, err
+	}
+
+	read := string(slurp)
+	val, _ := v.Default()
+	out := compiler.NewValue()
+
+	if plancontext.IsSecretValue(val) {
+		secret := pctx.Secrets.New(read)
+		return out.Fill(secret.MarshalCUE())
+	}
+
+	return out.Fill(read)
+}