metricator/internal/storage/memory/memory.go

107 lines
2.4 KiB
Go

package memory
import (
"context"
"errors"
"sync"
"go.dev.pztrn.name/metricator/internal/logger"
"go.dev.pztrn.name/metricator/internal/models"
)
// ErrMetricNotFound appears if requested metric wasn't found in storage.
var ErrMetricNotFound = errors.New("metric not found")
// Storage is an in-memory storage.
type Storage struct {
ctx context.Context
doneChan chan struct{}
logger *logger.Logger
data map[string]models.Metric
name string
dataMutex sync.RWMutex
}
// NewStorage creates new in-memory storage to use.
func NewStorage(ctx context.Context, name string, logger *logger.Logger) (*Storage, chan struct{}) {
s := &Storage{
ctx: ctx,
doneChan: make(chan struct{}),
logger: logger,
name: name,
}
s.initialize()
return s, s.doneChan
}
// Get returns data from storage by key.
func (s *Storage) Get(key string) (models.Metric, error) {
s.logger.Debugln("Retrieving data for", key, "key from storage...")
s.dataMutex.RLock()
defer s.dataMutex.RUnlock()
data, found := s.data[key]
if !found {
s.logger.Infoln("Key", key, "not found in storage!")
return models.NewMetric("", "", "", nil), ErrMetricNotFound
}
s.logger.Debugf("Key %s found: %+v\n", key, data)
return data, nil
}
// GetAsSlice returns all data from storage as slice.
func (s *Storage) GetAsSlice() []models.Metric {
s.logger.Debugln("Returning all stored metrics as slice...")
metrics := make([]models.Metric, 0, len(s.data))
for _, metric := range s.data {
metrics = append(metrics, metric)
}
return metrics
}
// GetDoneChan returns a channel which should be used to block execution
// until storage's routines are completed.
func (s *Storage) GetDoneChan() chan struct{} {
return s.doneChan
}
// Initializes internal things.
func (s *Storage) initialize() {
s.data = make(map[string]models.Metric)
}
// Put puts passed data into storage.
func (s *Storage) Put(data map[string]models.Metric) {
s.dataMutex.Lock()
defer s.dataMutex.Unlock()
for k, v := range data {
// We should not put valueless metrics.
if v.Value != "" {
s.data[k] = v
}
}
s.logger.Debugln("Put", len(data), "items in", s.name)
}
// Start starts asynchronous things if needed.
func (s *Storage) Start() {
// The Context Listening Goroutine.
go func() {
<-s.ctx.Done()
s.logger.Infoln("In-memory storage", s.name, "done")
s.doneChan <- struct{}{}
}()
}