Add the worker setup wizard (setup, --config, --check) to worker-agent

coordinator/internal/agent/configfile.go

@@ -0,0 +1,133 @@
+package agent
+
+import (
+	"encoding/json"
+	"fmt"
+	"os"
+	"path/filepath"
+	"strings"
+	"time"
+)
+
+// ConfigFile is the persisted worker configuration written by the setup
+// wizard and read back by `worker-agent --config`. Environment variables
+// still win: the file fills in what the environment left unset.
+type ConfigFile struct {
+	CoordinatorURL string   `json:"coordinator_url"`
+	Token          string   `json:"token,omitempty"`
+	WorkerKey      string   `json:"worker_key,omitempty"`
+	UserserviceURL string   `json:"userservice_url,omitempty"`
+	WorkDir        string   `json:"work_dir"`
+	WorkerName     string   `json:"worker_name,omitempty"`
+	CPUCount       int      `json:"cpu_count"`
+	MemoryMB       int      `json:"memory_mb"`
+	TaskRunner     []string `json:"task_runner,omitempty"`
+}
+
+// DefaultConfigPath is where the setup wizard stores the worker's
+// configuration. SCIMESH_WORKER_CONFIG overrides it.
+func DefaultConfigPath() string {
+	if raw := os.Getenv("SCIMESH_WORKER_CONFIG"); raw != "" {
+		return raw
+	}
+	home, err := os.UserHomeDir()
+	if err != nil || home == "" {
+		return filepath.Join(".", ".scimesh-worker", "config.json")
+	}
+	return filepath.Join(home, ".scimesh-worker", "config.json")
+}
+
+// LoadConfigFile reads and validates a persisted configuration. The file is
+// created by the wizard with 0600 permissions, so no credential is exposed to
+// other local users.
+func LoadConfigFile(path string) (*Config, error) {
+	raw, err := os.ReadFile(path)
+	if err != nil {
+		return nil, fmt.Errorf("read config file: %w", err)
+	}
+	var file ConfigFile
+	if err := json.Unmarshal(raw, &file); err != nil {
+		return nil, fmt.Errorf("parse config file: %w", err)
+	}
+	return file.Config()
+}
+
+// Config turns the file into the daemon configuration. Environment variables
+// take precedence so operators can still override any value per-process.
+func (f *ConfigFile) Config() (*Config, error) {
+	config := &Config{}
+	if env := os.Getenv("COORDINATOR_URL"); env != "" {
+		config.CoordinatorURL = env
+	} else {
+		config.CoordinatorURL = strings.TrimSpace(f.CoordinatorURL)
+	}
+	if config.CoordinatorURL == "" {
+		return nil, fmt.Errorf("coordinator_url is required")
+	}
+	if !strings.HasPrefix(config.CoordinatorURL, "http://") && !strings.HasPrefix(config.CoordinatorURL, "https://") {
+		return nil, fmt.Errorf("coordinator_url must be an absolute HTTP(S) URL")
+	}
+	if env := os.Getenv("WORKER_AUTH_TOKEN"); env != "" {
+		config.Token = env
+	} else {
+		config.Token = f.Token
+	}
+	if env := os.Getenv("WORKER_KEY"); env != "" {
+		config.WorkerKey = env
+	} else {
+		config.WorkerKey = f.WorkerKey
+	}
+	if env := os.Getenv("USERSERVICE_URL"); env != "" {
+		config.UserserviceURL = env
+	} else {
+		config.UserserviceURL = f.UserserviceURL
+	}
+	if env := os.Getenv("WORK_DIR"); env != "" {
+		config.WorkDir = env
+	} else if f.WorkDir != "" {
+		config.WorkDir = f.WorkDir
+	} else {
+		config.WorkDir = "./scimesh-agent-data"
+	}
+	if env := os.Getenv("WORKER_NAME"); env != "" {
+		config.WorkerName = env
+	} else {
+		config.WorkerName = f.WorkerName
+	}
+	config.CPUCount = f.CPUCount
+	if config.CPUCount < 1 {
+		config.CPUCount = 1
+	}
+	config.MemoryMB = f.MemoryMB
+	if config.MemoryMB < 0 {
+		config.MemoryMB = 0
+	}
+	if len(f.TaskRunner) > 0 {
+		config.TaskRunner = f.TaskRunner
+	}
+	if len(config.TaskRunner) == 0 {
+		config.TaskRunner = []string{"python", "-m", "scimesh.worker.task"}
+	}
+	config.PollInterval = 2 * time.Second
+	config.RequestTimeout = 30 * time.Second
+	config.Heartbeat = 15 * time.Second
+	config.Capabilities = DefaultCapabilities()
+	return config, nil
+}
+
+// Save writes the configuration file, creating the parent directory and
+// restricting permissions to the owner.
+func SaveConfigFile(path string, file ConfigFile) error {
+	payload, err := json.MarshalIndent(file, "", "  ")
+	if err != nil {
+		return err
+	}
+	payload = append(payload, '\n')
+	if err := os.MkdirAll(filepath.Dir(path), 0o700); err != nil {
+		return fmt.Errorf("create config directory: %w", err)
+	}
+	if err := os.WriteFile(path, payload, 0o600); err != nil {
+		return fmt.Errorf("write config file: %w", err)
+	}
+	return nil
+}