Renamed collector, aggregator to api server, api folder to agent (#133)

* Renamed aggregator -> apiServer.

* Format errors with container names.

* Renamed collector -> apiServer.

* Rephrased help messages.

* Moved api -> agent.

* Continue renameing api -> agent in Makefile and Dockerfiles.

agent/pkg/utils/pathUtils.go

@@ -0,0 +1,50 @@
+package utils
+
+import (
+	"github.com/djherbis/atime"
+	"os"
+)
+
+type ByModTime []os.FileInfo
+
+func (fis ByModTime) Len() int {
+	return len(fis)
+}
+
+func (fis ByModTime) Swap(i, j int) {
+	fis[i], fis[j] = fis[j], fis[i]
+}
+
+func (fis ByModTime) Less(i, j int) bool {
+	return fis[i].ModTime().Before(fis[j].ModTime())
+}
+
+
+type ByName []os.FileInfo
+
+func (fis ByName) Len() int {
+	return len(fis)
+}
+
+func (fis ByName) Swap(i, j int) {
+	fis[i], fis[j] = fis[j], fis[i]
+}
+
+func (fis ByName) Less(i, j int) bool {
+	return fis[i].Name() < fis[j].Name()
+}
+
+
+type ByCreationTime []os.FileInfo
+
+func (fis ByCreationTime) Len() int {
+	return len(fis)
+}
+
+func (fis ByCreationTime) Swap(i, j int) {
+	fis[i], fis[j] = fis[j], fis[i]
+}
+
+func (fis ByCreationTime) Less(i, j int) bool {
+	return atime.Get(fis[i]).Unix() < atime.Get(fis[j]).Unix()
+}

agent/pkg/utils/randomString.go

@@ -0,0 +1,22 @@
+package utils
+
+import (
+	"math/rand"
+	"time"
+)
+
+const charset = "abcdefghijklmnopqrstuvwxyz" + "ABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789"
+
+var seededRand = rand.New(rand.NewSource(time.Now().UnixNano()))
+
+func StringWithCharset(length int, charset string) string {
+	b := make([]byte, length)
+	for i := range b {
+		b[i] = charset[seededRand.Intn(len(charset))]
+	}
+	return string(b)
+}
+
+func GetRandomString(length int) string {
+	return StringWithCharset(length, charset)
+}

agent/pkg/utils/truncating_logger.go

@@ -0,0 +1,58 @@
+package utils
+
+import (
+	"context"
+	"fmt"
+	"gorm.io/gorm/logger"
+	"gorm.io/gorm/utils"
+	"time"
+)
+
+// TruncatingLogger implements the gorm logger.Interface interface. Its purpose is to act as gorm's logger while truncating logs to a max of 50 characters to minimise the performance impact
+type TruncatingLogger struct {
+	LogLevel logger.LogLevel
+	SlowThreshold time.Duration
+}
+
+func (truncatingLogger *TruncatingLogger) LogMode(logLevel logger.LogLevel) logger.Interface {
+	truncatingLogger.LogLevel = logLevel
+	return truncatingLogger
+}
+
+func (truncatingLogger *TruncatingLogger) Info(_ context.Context, message string, __ ...interface{}) {
+	if truncatingLogger.LogLevel < logger.Info {
+		return
+	}
+	fmt.Printf("gorm info: %.150s\n", message)
+}
+
+func (truncatingLogger *TruncatingLogger) Warn(_ context.Context, message string, __ ...interface{}) {
+	if truncatingLogger.LogLevel < logger.Warn {
+		return
+	}
+	fmt.Printf("gorm warning: %.150s\n", message)
+}
+
+func (truncatingLogger *TruncatingLogger) Error(_ context.Context, message string, __ ...interface{}) {
+	if truncatingLogger.LogLevel < logger.Error {
+		return
+	}
+	fmt.Printf("gorm error: %.150s\n", message)
+}
+
+func (truncatingLogger *TruncatingLogger) Trace(ctx context.Context, begin time.Time, fc func() (string, int64), err error) {
+	if truncatingLogger.LogLevel == logger.Silent {
+		return
+	}
+	elapsed := time.Since(begin)
+	if err != nil {
+		sql, rows := fc() // copied into every condition as this is a potentially heavy operation best done only when necessary
+		truncatingLogger.Error(ctx, fmt.Sprintf("Error in %s: %v - elapsed: %fs affected rows: %d, sql: %s", utils.FileWithLineNum(), err, elapsed.Seconds(), rows, sql))
+	} else if truncatingLogger.LogLevel >= logger.Warn && elapsed > truncatingLogger.SlowThreshold {
+		sql, rows := fc()
+		truncatingLogger.Warn(ctx, fmt.Sprintf("Slow sql query - elapse: %fs rows: %d, sql: %s", elapsed.Seconds(), rows, sql))
+	} else if truncatingLogger.LogLevel >= logger.Info {
+		sql, rows := fc()
+		truncatingLogger.Info(ctx, fmt.Sprintf("Sql query - elapse: %fs rows: %d, sql: %s", elapsed.Seconds(), rows, sql))
+	}
+}

agent/pkg/utils/utils.go

@@ -0,0 +1,61 @@
+package utils
+
+import (
+	"github.com/gofiber/fiber/v2"
+	"github.com/romana/rlog"
+	"log"
+	"net/url"
+	"os"
+	"os/signal"
+	"reflect"
+	"syscall"
+)
+
+// StartServer starts the server with a graceful shutdown
+func StartServer(app *fiber.App) {
+	signals := make(chan os.Signal, 2)
+	signal.Notify(signals,
+		os.Interrupt,  	  // this catch ctrl + c
+		syscall.SIGTSTP,  // this catch ctrl + z
+	)
+
+	go func() {
+		_ = <-signals
+		rlog.Infof("Shutting down...")
+		_ = app.Shutdown()
+	}()
+
+	// Run server.
+	if err := app.Listen(":8899"); err != nil {
+		log.Printf("Oops... Server is not running! Reason: %v", err)
+	}
+}
+
+func ReverseSlice(data interface{}) {
+	value := reflect.ValueOf(data)
+	valueLen := value.Len()
+	for i := 0; i <= int((valueLen-1)/2); i++ {
+		reverseIndex := valueLen - 1 - i
+		tmp := value.Index(reverseIndex).Interface()
+		value.Index(reverseIndex).Set(value.Index(i))
+		value.Index(i).Set(reflect.ValueOf(tmp))
+	}
+}
+
+func CheckErr(e error) {
+	if e != nil {
+		log.Printf("%v", e)
+		//panic(e)
+	}
+}
+
+func SetHostname(address, newHostname string) string {
+	replacedUrl, err := url.Parse(address)
+	if err != nil{
+		log.Printf("error replacing hostname to %s in address %s, returning original %v",newHostname, address, err)
+		return address
+	}
+	replacedUrl.Host = newHostname
+	return replacedUrl.String()
+
+}

agent/pkg/utils/zip.go

@@ -0,0 +1,20 @@
+package utils
+
+import (
+	"archive/zip"
+	"bytes"
+)
+
+func ZipData(files map[string][]byte) *bytes.Buffer {
+	// Create a buffer to write our archive to.
+	buf := new(bytes.Buffer)
+	// Create a new zip archive.
+	zipWriter := zip.NewWriter(buf)
+	defer func() { _ = zipWriter.Close() }()
+
+	for fileName, fileBytes := range files {
+		zipFile, _ := zipWriter.Create(fileName)
+		_, _ = zipFile.Write(fileBytes)
+	}
+	return buf
+}