chore: Add memory history endpoint to API

Author: andrasbacsai

cmd/sentinel/main.go

@@ -15,6 +15,7 @@ var version string = "0.0.5"
 var logsDir string = "/app/logs"
 var metricsDir string = "/app/metrics"
 var cpuMetricsFile string = metricsDir + "/cpu.csv"
+var memoryMetricsFile string = metricsDir + "/memory.csv"
 
 // Arguments
 var token string
@@ -41,6 +42,7 @@ func main() {
 		logsDir = "./logs"
 		metricsDir = "./metrics"
 		cpuMetricsFile = metricsDir + "/cpu.csv"
+		memoryMetricsFile = metricsDir + "/memory.csv"
 	}
 	if err := os.MkdirAll(logsDir, 0700); err != nil {
 		log.Fatalf("Error creating metrics directory: %v", err)
@@ -173,6 +175,18 @@ func main() {
 			usage = memoryCsvHeader + usage
 			c.String(200, usage)
 		})
+		authorized.GET("/memory/history", func(c *gin.Context) {
+			from := c.Query("from")
+			to := c.Query("to")
+			usage, err := getHistoryMemoryUsage(from, to)
+			if err != nil {
+				c.JSON(500, gin.H{
+					"error": err.Error(),
+				})
+				return
+			}
+			c.String(200, usage)
+		})
 		authorized.GET("/disk", func(c *gin.Context) {
 			usage, err := getDiskUsage()
 			if err != nil {

cmd/sentinel/memory.go

@@ -3,6 +3,10 @@ package main
 import (
 	"encoding/json"
 	"fmt"
+	"os"
+	"strconv"
+	"strings"
+	"time"
 
 	"github.com/shirou/gopsutil/mem"
 )
@@ -44,3 +48,63 @@ func getMemUsage(csv bool) (string, error) {
 	return string(jsonData), nil
 
 }
+
+func getHistoryMemoryUsage(from string, to string) (string, error) {
+	if from == "" && to == "" {
+		// return everything
+		file, err := os.ReadFile(memoryMetricsFile)
+		if err != nil {
+			fmt.Println("Failed to read file:", err)
+			return "", err
+		}
+		return string(file), nil
+	}
+	if from == "" {
+		from = "1970-01-01T00:00:00Z"
+	}
+	if to == "" {
+		to = time.Now().UTC().Format(time.RFC3339)
+	}
+	fromTime, err := time.Parse(time.RFC3339, from)
+	if err != nil {
+		fmt.Println("Failed to parse from time:", err)
+		return "", err
+	}
+	toTime, err := time.Parse(time.RFC3339, to)
+	if err != nil {
+		fmt.Println("Failed to parse to time:", err)
+		return "", err
+	}
+
+	fromTimeUnix := fromTime.UnixMilli()
+	toTimeUnix := toTime.UnixMilli()
+	file, err := os.ReadFile(memoryMetricsFile)
+	if err != nil {
+		fmt.Println("Failed to read file:", err)
+		return "", err
+	}
+	lines := string(file)
+	var result string
+	lines = lines[strings.Index(lines, "\n")+1:]
+	for _, line := range strings.Split(lines, "\n") {
+		if line == "" {
+			continue
+		}
+		parts := strings.Split(line, ",")
+		if len(parts) != 4 {
+			fmt.Println("Invalid line:", line)
+			continue
+		}
+		time, err := strconv.ParseInt(parts[0], 10, 64)
+		if err != nil {
+			fmt.Println("Failed to parse time:", err)
+			continue
+		}
+		if time >= fromTimeUnix && time <= toTimeUnix {
+			result += line + "\n"
+		}
+	}
+	result = memoryCsvHeader + result
+	return result, nil
+
+}