Files
tidb/br/pkg/pdutil/utils.go

84 lines
2.2 KiB
Go

// Copyright 2020 PingCAP, Inc. Licensed under Apache-2.0.
package pdutil
import (
"bytes"
"context"
"crypto/tls"
"encoding/hex"
"encoding/json"
"fmt"
"net/http"
"github.com/pingcap/errors"
berrors "github.com/pingcap/tidb/br/pkg/errors"
"github.com/pingcap/tidb/br/pkg/httputil"
"github.com/pingcap/tidb/pkg/store/pdtypes"
"github.com/pingcap/tidb/pkg/tablecodec"
"github.com/pingcap/tidb/pkg/util/codec"
pd "github.com/tikv/pd/client/http"
)
// UndoFunc is a 'undo' operation of some undoable command.
// (e.g. RemoveSchedulers).
type UndoFunc func(context.Context) error
// Nop is the 'zero value' of undo func.
var Nop UndoFunc = func(context.Context) error { return nil }
// GetPlacementRules return the current placement rules.
func GetPlacementRules(ctx context.Context, pdAddr string, tlsConf *tls.Config) ([]pdtypes.Rule, error) {
cli := httputil.NewClient(tlsConf)
prefix := "http://"
if tlsConf != nil {
prefix = "https://"
}
reqURL := fmt.Sprintf("%s%s%s", prefix, pdAddr, pd.PlacementRules)
req, err := http.NewRequestWithContext(ctx, "GET", reqURL, nil)
if err != nil {
return nil, errors.Trace(err)
}
resp, err := cli.Do(req)
if err != nil {
return nil, errors.Trace(err)
}
defer resp.Body.Close()
buf := new(bytes.Buffer)
_, err = buf.ReadFrom(resp.Body)
if err != nil {
return nil, errors.Trace(err)
}
if resp.StatusCode == http.StatusPreconditionFailed {
return []pdtypes.Rule{}, nil
}
if resp.StatusCode != http.StatusOK {
return nil, errors.Annotatef(berrors.ErrPDInvalidResponse,
"get placement rules failed: resp=%v, err=%v, code=%d", buf.String(), err, resp.StatusCode)
}
var rules []pdtypes.Rule
err = json.Unmarshal(buf.Bytes(), &rules)
if err != nil {
return nil, errors.Trace(err)
}
return rules, nil
}
// SearchPlacementRule returns the placement rule matched to the table or nil.
func SearchPlacementRule(tableID int64, placementRules []pdtypes.Rule, role pdtypes.PeerRoleType) *pdtypes.Rule {
for _, rule := range placementRules {
key, err := hex.DecodeString(rule.StartKeyHex)
if err != nil {
continue
}
_, decoded, err := codec.DecodeBytes(key, nil)
if err != nil {
continue
}
if rule.Role == role && tableID == tablecodec.DecodeTableID(decoded) {
return &rule
}
}
return nil
}