grafana/pkg/services/live/managedstream/cache_redis.go
idafurjes 56c3875bb9
Chore: Remove context.TODO (#43458)
* Remove context.TODO() from services

* Fix live test
2021-12-28 10:26:18 +01:00

113 lines
2.6 KiB
Go

package managedstream
import (
"context"
"encoding/json"
"errors"
"sync"
"time"
"github.com/grafana/grafana/pkg/services/live/orgchannel"
"github.com/go-redis/redis/v8"
"github.com/grafana/grafana-plugin-sdk-go/data"
)
// RedisFrameCache ...
type RedisFrameCache struct {
mu sync.RWMutex
redisClient *redis.Client
frames map[int64]map[string]data.FrameJSONCache
}
// NewRedisFrameCache ...
func NewRedisFrameCache(redisClient *redis.Client) *RedisFrameCache {
return &RedisFrameCache{
frames: map[int64]map[string]data.FrameJSONCache{},
redisClient: redisClient,
}
}
func (c *RedisFrameCache) GetActiveChannels(orgID int64) (map[string]json.RawMessage, error) {
c.mu.RLock()
defer c.mu.RUnlock()
frames, ok := c.frames[orgID]
if !ok {
return nil, nil
}
info := make(map[string]json.RawMessage, len(frames))
for k, v := range frames {
info[k] = v.Bytes(data.IncludeSchemaOnly)
}
return info, nil
}
func (c *RedisFrameCache) GetFrame(ctx context.Context, orgID int64, channel string) (json.RawMessage, bool, error) {
key := getCacheKey(orgchannel.PrependOrgID(orgID, channel))
cmd := c.redisClient.HGetAll(ctx, key)
result, err := cmd.Result()
if err != nil {
return nil, false, err
}
if len(result) == 0 {
return nil, false, nil
}
return json.RawMessage(result["frame"]), true, nil
}
const (
frameCacheTTL = 7 * 24 * time.Hour
)
func (c *RedisFrameCache) Update(ctx context.Context, orgID int64, channel string, jsonFrame data.FrameJSONCache) (bool, error) {
c.mu.Lock()
if _, ok := c.frames[orgID]; !ok {
c.frames[orgID] = map[string]data.FrameJSONCache{}
}
c.frames[orgID][channel] = jsonFrame
c.mu.Unlock()
stringSchema := string(jsonFrame.Bytes(data.IncludeSchemaOnly))
key := getCacheKey(orgchannel.PrependOrgID(orgID, channel))
pipe := c.redisClient.TxPipeline()
defer func() { _ = pipe.Close() }()
pipe.HGetAll(ctx, key)
pipe.HMSet(ctx, key, map[string]string{
"schema": stringSchema,
"frame": string(jsonFrame.Bytes(data.IncludeAll)),
})
pipe.Expire(ctx, key, frameCacheTTL)
replies, err := pipe.Exec(ctx)
if err != nil {
return false, err
}
if len(replies) == 0 {
return false, errors.New("no replies in response")
}
reply := replies[0]
if reply.Err() != nil {
return false, err
}
if mapReply, ok := reply.(*redis.StringStringMapCmd); ok {
result, err := mapReply.Result()
if err != nil {
return false, err
}
if len(result) == 0 {
return true, nil
}
return result["schema"] != stringSchema, nil
}
return true, nil
}
func getCacheKey(channelID string) string {
return "gf_live.managed_stream." + channelID
}