vitess.io/vitess@v0.16.2/go/vt/srvtopo/query_srvkeyspacenames.go (about)

     1  /*
     2  Copyright 2021 The Vitess Authors.
     3  
     4  Licensed under the Apache License, Version 2.0 (the "License");
     5  you may not use this file except in compliance with the License.
     6  You may obtain a copy of the License at
     7  
     8      http://www.apache.org/licenses/LICENSE-2.0
     9  
    10  Unless required by applicable law or agreed to in writing, software
    11  distributed under the License is distributed on an "AS IS" BASIS,
    12  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    13  See the License for the specific language governing permissions and
    14  limitations under the License.
    15  */
    16  
    17  package srvtopo
    18  
    19  import (
    20  	"context"
    21  	"time"
    22  
    23  	"vitess.io/vitess/go/stats"
    24  	"vitess.io/vitess/go/vt/topo"
    25  )
    26  
    27  type SrvKeyspaceNamesQuery struct {
    28  	rq *resilientQuery
    29  }
    30  
    31  func NewSrvKeyspaceNamesQuery(topoServer *topo.Server, counts *stats.CountersWithSingleLabel, cacheRefresh, cacheTTL time.Duration) *SrvKeyspaceNamesQuery {
    32  	query := func(ctx context.Context, entry *queryEntry) (any, error) {
    33  		cell := entry.key.(cellName)
    34  		return topoServer.GetSrvKeyspaceNames(ctx, string(cell))
    35  	}
    36  
    37  	rq := &resilientQuery{
    38  		query:                query,
    39  		counts:               counts,
    40  		cacheRefreshInterval: cacheRefresh,
    41  		cacheTTL:             cacheTTL,
    42  		entries:              make(map[string]*queryEntry),
    43  	}
    44  
    45  	return &SrvKeyspaceNamesQuery{rq}
    46  }
    47  
    48  func (q *SrvKeyspaceNamesQuery) GetSrvKeyspaceNames(ctx context.Context, cell string, staleOK bool) ([]string, error) {
    49  	v, err := q.rq.getCurrentValue(ctx, cellName(cell), staleOK)
    50  	names, _ := v.([]string)
    51  	return names, err
    52  }
    53  
    54  func (q *SrvKeyspaceNamesQuery) srvKeyspaceNamesCacheStatus() (result []*SrvKeyspaceNamesCacheStatus) {
    55  	q.rq.mutex.Lock()
    56  	defer q.rq.mutex.Unlock()
    57  
    58  	for _, entry := range q.rq.entries {
    59  		entry.mutex.Lock()
    60  		value, _ := entry.value.([]string)
    61  		result = append(result, &SrvKeyspaceNamesCacheStatus{
    62  			Cell:           entry.key.String(),
    63  			Value:          value,
    64  			ExpirationTime: entry.insertionTime.Add(q.rq.cacheTTL),
    65  			LastQueryTime:  entry.lastQueryTime,
    66  			LastError:      entry.lastError,
    67  		})
    68  		entry.mutex.Unlock()
    69  	}
    70  	return
    71  }