validate.go

// Copyright 2020 The Cockroach Authors.
//
// Licensed as a CockroachDB Enterprise file under the Cockroach Community
// License (the "License"); you may not use this file except in compliance with
// the License. You may obtain a copy of the License at
//
//     https://github.com/cockroachdb/cockroach/blob/master/licenses/CCL.txt

package changefeedbase

import (
	"github.com/cockroachdb/cockroach/pkg/jobs/jobspb"
	"github.com/cockroachdb/cockroach/pkg/sql/catalog"
	"github.com/cockroachdb/errors"
)

// ValidateTable validates that a table descriptor can be watched by a CHANGEFEED.
func ValidateTable(targets jobspb.ChangefeedTargets, tableDesc catalog.TableDescriptor) error {
	t, ok := targets[tableDesc.GetID()]
	if !ok {
		return errors.Errorf(`unwatched table: %s`, tableDesc.GetName())
	}

	// Technically, the only non-user table known not to work is system.jobs
	// (which creates a cycle since the resolved timestamp high-water mark is
	// saved in it), but there are subtle differences in the way many of them
	// work and this will be under-tested, so disallow them all until demand
	// dictates.
	if catalog.IsSystemDescriptor(tableDesc) {
		return errors.Errorf(`CHANGEFEEDs are not supported on system tables`)
	}
	if tableDesc.IsView() {
		return errors.Errorf(`CHANGEFEED cannot target views: %s`, tableDesc.GetName())
	}
	if tableDesc.IsVirtualTable() {
		return errors.Errorf(`CHANGEFEED cannot target virtual tables: %s`, tableDesc.GetName())
	}
	if tableDesc.IsSequence() {
		return errors.Errorf(`CHANGEFEED cannot target sequences: %s`, tableDesc.GetName())
	}
	if len(tableDesc.GetFamilies()) != 1 {
		return errors.Errorf(
			`CHANGEFEEDs are currently supported on tables with exactly 1 column family: %s has %d`,
			tableDesc.GetName(), len(tableDesc.GetFamilies()))
	}

	if tableDesc.Dropped() {
		return errors.Errorf(`"%s" was dropped`, t.StatementTimeName)
	}

	if tableDesc.Offline() {
		return errors.Errorf("CHANGEFEED cannot target offline table: %s (offline reason: %q)", tableDesc.GetName(), tableDesc.GetOfflineReason())
	}

	return nil
}