cluster: rename Zones to Cluster

Signed-off-by: Alejandro Mery <amery@jpi.io>

pkg/cluster/cluster_scan_options.go

@@ -0,0 +1,134 @@
+package cluster
+
+import (
+	"io/fs"
+	"path/filepath"
+
+	"darvaza.org/resolver"
+	"darvaza.org/slog"
+	"darvaza.org/slog/handlers/discard"
+	"github.com/hack-pad/hackpadfs/os"
+)
+
+// A ScanOption pre-configures the Zones before scanning
+type ScanOption func(*Cluster, *ScanOptions) error
+
+// ScanOptions contains flags used by the initial scan
+type ScanOptions struct {
+	// DontResolvePublicAddresses indicates we shouldn't
+	// pre-populate Machine.PublicAddresses during the
+	// initial scan
+	DontResolvePublicAddresses bool
+
+	// Logger specifies the logger to be used. otherwise
+	// the scanner will be mute
+	slog.Logger
+}
+
+// ResolvePublicAddresses instructs the scanner to use
+// the DNS resolver to get PublicAddresses of nodes.
+// Default is true
+func ResolvePublicAddresses(resolve bool) ScanOption {
+	return func(m *Cluster, opt *ScanOptions) error {
+		opt.DontResolvePublicAddresses = !resolve
+		return nil
+	}
+}
+
+// WithLookuper specifies what resolver.Lookuper to use to
+// find public addresses
+func WithLookuper(h resolver.Lookuper) ScanOption {
+	return func(m *Cluster, opt *ScanOptions) error {
+		if h == nil {
+			return fs.ErrInvalid
+		}
+		m.resolver = resolver.NewResolver(h)
+		return nil
+	}
+}
+
+// WithResolver specifies what resolver to use to find
+// public addresses. if nil is passed, the [net.Resolver] will be used.
+// The default is using Cloudflare's 1.1.1.1.
+func WithResolver(h resolver.Resolver) ScanOption {
+	return func(m *Cluster, opt *ScanOptions) error {
+		if h == nil {
+			h = resolver.SystemResolver(true)
+		}
+
+		m.resolver = h
+		return nil
+	}
+}
+
+// WithLogger specifies what to use for logging
+func WithLogger(log slog.Logger) ScanOption {
+	return func(m *Cluster, opt *ScanOptions) error {
+		if log == nil {
+			log = discard.New()
+		}
+
+		opt.Logger = log
+		m.log = log
+		return nil
+	}
+}
+
+func (m *Cluster) setDefaults(opt *ScanOptions) error {
+	if m.resolver == nil {
+		h := resolver.NewCloudflareLookuper()
+
+		if err := WithLookuper(h)(m, opt); err != nil {
+			return err
+		}
+	}
+
+	if opt.Logger == nil {
+		if err := WithLogger(nil)(m, opt); err != nil {
+			return err
+		}
+	}
+
+	return nil
+}
+
+// NewFS builds a [Cluster] tree using the given directory
+func NewFS(dir fs.FS, domain string, opts ...ScanOption) (*Cluster, error) {
+	var scanOptions ScanOptions
+
+	z := &Cluster{
+		dir:    dir,
+		domain: domain,
+	}
+
+	for _, opt := range opts {
+		if err := opt(z, &scanOptions); err != nil {
+			return nil, err
+		}
+	}
+
+	if err := z.setDefaults(&scanOptions); err != nil {
+		return nil, err
+	}
+
+	if err := z.scan(&scanOptions); err != nil {
+		return nil, err
+	}
+
+	return z, nil
+}
+
+// New builds a [Cluster] tree using the given directory
+func New(dir, domain string, opts ...ScanOption) (*Cluster, error) {
+	dir, err := filepath.Abs(dir)
+	if err != nil {
+		return nil, err
+	}
+
+	base, err := os.NewFS().Sub(dir[1:])
+	if err != nil {
+		return nil, err
+	}
+
+	return NewFS(base, domain, opts...)
+}