move implementation to internal/ directory (#828)

internal/endpoint/jobid.go

@@ -0,0 +1,78 @@
+package endpoint
+
+import (
+	"encoding/json"
+	"fmt"
+
+	"github.com/pkg/errors"
+
+	"github.com/zrepl/zrepl/internal/zfs"
+)
+
+// JobID instances returned by MakeJobID() guarantee their JobID.String()
+// can be used in ZFS dataset names and hold tags.
+type JobID struct {
+	jid string
+}
+
+func MakeJobID(s string) (JobID, error) {
+	if len(s) == 0 {
+		return JobID{}, fmt.Errorf("must not be empty string")
+	}
+
+	if err := zfs.ComponentNamecheck(s); err != nil {
+		return JobID{}, errors.Wrap(err, "must be usable as a dataset path component")
+	}
+
+	if _, err := tentativeReplicationCursorBookmarkNameImpl("pool/ds", 0xface601d, s); err != nil {
+		// note that this might still fail due to total maximum name length, but we can't enforce that
+		return JobID{}, errors.Wrap(err, "must be usable for a tentative replication cursor bookmark")
+	}
+
+	if _, err := stepHoldTagImpl(s); err != nil {
+		return JobID{}, errors.Wrap(err, "must be usable for a step hold tag")
+	}
+
+	if _, err := lastReceivedHoldImpl(s); err != nil {
+		return JobID{}, errors.Wrap(err, "must be usable as a last-received-hold tag")
+	}
+
+	// FIXME replication cursor bookmark name
+
+	_, err := zfs.NewDatasetPath(s)
+	if err != nil {
+		return JobID{}, fmt.Errorf("must be usable in a ZFS dataset path: %s", err)
+	}
+
+	return JobID{s}, nil
+}
+
+func MustMakeJobID(s string) JobID {
+	jid, err := MakeJobID(s)
+	if err != nil {
+		panic(err)
+	}
+	return jid
+}
+
+func (j JobID) expectInitialized() {
+	if j.jid == "" {
+		panic("use of uninitialized JobID")
+	}
+}
+
+func (j JobID) String() string {
+	j.expectInitialized()
+	return j.jid
+}
+
+var _ json.Marshaler = JobID{}
+var _ json.Unmarshaler = (*JobID)(nil)
+
+func (j JobID) MarshalJSON() ([]byte, error) { return json.Marshal(j.jid) }
+
+func (j *JobID) UnmarshalJSON(b []byte) error {
+	return json.Unmarshal(b, &j.jid)
+}
+
+func (j JobID) MustValidate() { j.expectInitialized() }