package svc import ( "encoding/gob" "fmt" "io" "os" "time" "tea.chunkbyte.com/kato/drive-health/lib/config" "tea.chunkbyte.com/kato/drive-health/lib/hardware" ) // The path to where the snapshot database is located const SNAPSHOT_LIST_PATH = "./snapshots.dat" // A simple in-memory buffer for the history of snapshots var snapShotBuffer []*HardwareSnapshot // A snapshot in time of the current state of the harddrives type HardwareSnapshot struct { TimeStamp time.Time HDD []*hardware.HardDrive } type Snapshots struct { List []*HardwareSnapshot } // The function itterates through all hard disks and takes a snapshot of their state, // returns a struct which contains metadata as well as the harddrives themselves. func TakeHardwareSnapshot() (*HardwareSnapshot, error) { drives, err := hardware.GetSystemHardDrives() if err != nil { return nil, err } snapShot := &HardwareSnapshot{ TimeStamp: time.Now(), HDD: []*hardware.HardDrive{}, } for _, hdd := range drives { hdd.GetTemperature(true) snapShot.HDD = append(snapShot.HDD, hdd) } // Append to the in-memory listing snapShotBuffer = append(snapShotBuffer, snapShot) // Return the snapshot just in case there is any need to modify it, // any modification to it will also affect the current buffer from memory. return snapShot, nil } // The function wil check if the `.dat` file is present, if it is then it will load it into memory func UpdateHardwareSnapshotsFromFile() { file, err := os.Open(SNAPSHOT_LIST_PATH) if err != nil { if os.IsNotExist(err) { return // File does not exist, no snapshots to load } panic(err) // Handle error according to your error handling policy } defer file.Close() decoder := gob.NewDecoder(file) var snapshots Snapshots if err := decoder.Decode(&snapshots); err != nil { if err == io.EOF { return // End of file reached } panic(err) // Handle error according to your error handling policy } snapShotBuffer = snapshots.List fmt.Printf("Loaded %v snapshots from .dat", len(snapShotBuffer)) } // Get the list of snapshots that have been buffered in memory func GetHardwareSnapshot() []*HardwareSnapshot { return snapShotBuffer } // Dump the current snapshot history from memory to file func SaveSnapshotsToFile() error { file, err := os.Create(SNAPSHOT_LIST_PATH) if err != nil { return err } defer file.Close() encoder := gob.NewEncoder(file) snapshots := Snapshots{List: snapShotBuffer} if err := encoder.Encode(snapshots); err != nil { return err } return nil } func RunService() { // Snapshot taking routine go func() { waitTime := time.Duration(config.GetConfiguration().DiskFetchFrequency) * time.Second for { time.Sleep(waitTime) _, err := TakeHardwareSnapshot() if err != nil { fmt.Printf("Hardware Fetch Error: %s", err) } } }() // Periodic saving routine go func() { for { waitTime := time.Duration(config.GetConfiguration().MemoryDumpFrequency) * time.Second time.Sleep(waitTime) err := SaveSnapshotsToFile() if err != nil { fmt.Printf("Memory Dump Error: %s", err) } } }() }