Use logging in place of println

README.org

@@ -23,7 +23,7 @@ Usage: S3Thorp [options]
 
 - [x] Improve test coverage
 - [ ] Create os-native binaries
-- [ ] Replace println with real logging
+- [x] Replace println with real logging
 - [ ] Add support for logging options
 - [ ] Add support for exclusion filters
 - [ ] Bulk fetching of Hash values from S3

src/main/scala/net/kemitix/s3thorp/Logging.scala

@@ -0,0 +1,7 @@
+package net.kemitix.s3thorp
+
+import com.typesafe.scalalogging.LazyLogging
+
+trait Logging extends LazyLogging {
+
+}

src/main/scala/net/kemitix/s3thorp/Main.scala

@@ -6,9 +6,7 @@ import cats.effect.ExitCase.{Canceled, Completed, Error}
 import cats.effect.{ExitCode, IO, IOApp}
 import net.kemitix.s3thorp.awssdk.S3Client
 
-object Main extends IOApp {
-
-  def putStrLn(value: String) = IO { println(value) }
+object Main extends IOApp with Logging {
 
   val defaultConfig: Config =
     Config("(none)", "", Paths.get(".").toFile)
@@ -17,7 +15,7 @@ object Main extends IOApp {
 
   def program(args: List[String]): IO[ExitCode] =
     for {
-      _ <- putStrLn("S3Thorp - hashed sync for s3")
+      _ <- IO(logger.info("S3Thorp - hashed sync for s3"))
       a <- ParseArgs(args, defaultConfig)
       _ <- sync.run(a)
     } yield ExitCode.Success
@@ -25,9 +23,9 @@ object Main extends IOApp {
   override def run(args: List[String]): IO[ExitCode] =
     program(args)
       .guaranteeCase {
-        case Canceled => IO(println("Interrupted"))
-        case Error(e) => IO(println("ERROR: " + e.getMessage))
-        case Completed => IO(println("Done"))
+        case Canceled => IO(logger.warn("Interrupted"))
+        case Error(e) => IO(logger.error(e.getMessage))
+        case Completed => IO(logger.info("Done"))
       }
 
 }

src/main/scala/net/kemitix/s3thorp/S3MetaDataEnricher.scala

@@ -6,13 +6,16 @@ import fs2.Stream
 import cats.effect.IO
 import net.kemitix.s3thorp.awssdk.S3Client
 
-trait S3MetaDataEnricher extends S3Client with KeyGenerator {
+trait S3MetaDataEnricher
+  extends S3Client
+    with KeyGenerator
+    with Logging {
 
   def enrichWithS3MetaData(c: Config): File => Stream[IO, Either[File, S3MetaData]] = {
     val remoteKey = generateKey(c)_
     file =>
       Stream.eval({
-        println(s"- Consider: ${c.relativePath(file)}")
+        logger.info(s"- Consider: ${c.relativePath(file)}")
         val key = remoteKey(file)
         for {
           head <- objectHead(c.bucket, key)

src/main/scala/net/kemitix/s3thorp/S3Uploader.scala

@@ -4,12 +4,12 @@ import java.io.File
 
 import fs2.Stream
 import cats.effect.IO
-import net.kemitix.s3thorp.Main.putStrLn
 import net.kemitix.s3thorp.awssdk.S3Client
 
 trait S3Uploader
   extends S3Client
-    with KeyGenerator {
+    with KeyGenerator
+    with Logging {
 
   def performUpload(c: Config): File => Stream[IO, Unit] = {
     val remoteKey = generateKey(c) _
@@ -17,9 +17,9 @@ trait S3Uploader
       val key = remoteKey(file)
       val shortFile = c.relativePath(file)
       Stream.eval(for {
-        _ <- putStrLn(s"    Upload: $shortFile")
+        _ <- IO(logger.info(s"    Upload: $shortFile"))
         _ <- upload(file, c.bucket, key)
-        _ <- putStrLn(s"      Done: $shortFile")
+        _ <- IO(logger.info(s"      Done: $shortFile"))
       } yield ())
     }
   }

src/main/scala/net/kemitix/s3thorp/Sync.scala

@@ -11,7 +11,8 @@ class Sync(s3Client: S3Client)
   extends LocalFileStream
     with S3MetaDataEnricher
     with UploadSelectionFilter
-    with S3Uploader {
+    with S3Uploader
+    with Logging {
 
   override def objectHead(bucket: Bucket, remoteKey: RemoteKey)=
     s3Client.objectHead(bucket, remoteKey)
@@ -20,7 +21,7 @@ class Sync(s3Client: S3Client)
     s3Client.upload(localFile, bucket, remoteKey)
 
   def run(c: Config): IO[Unit] = {
-    println(s"Bucket: ${c.bucket}, Prefix: ${c.prefix}, Source: ${c.source}")
+    logger.info(s"Bucket: ${c.bucket}, Prefix: ${c.prefix}, Source: ${c.source}")
     streamDirectoryPaths(c.source).flatMap(
       enrichWithS3MetaData(c)).flatMap(
       uploadRequiredFilter(c)).flatMap(

src/main/scala/net/kemitix/s3thorp/UploadSelectionFilter.scala

@@ -6,7 +6,8 @@ import net.kemitix.s3thorp.Sync.{MD5Hash, LocalFile}
 import java.security.{MessageDigest, DigestInputStream}
 import java.io.{File, FileInputStream}
 
-trait UploadSelectionFilter {
+trait UploadSelectionFilter
+  extends Logging {
 
   private def md5File(localFile: LocalFile): MD5Hash =  {
     val buffer = new Array[Byte](8192)
@@ -20,7 +21,7 @@ trait UploadSelectionFilter {
 
   def uploadRequiredFilter(c: Config): Either[File, S3MetaData] => Stream[IO, File] = {
     case Left(file) => {
-      println(s"   Created: ${c.relativePath(file)}")
+      logger.info(s"   Created: ${c.relativePath(file)}")
       Stream(file)
     }
     case Right(s3Metadata) =>
@@ -30,7 +31,7 @@ trait UploadSelectionFilter {
         filter { case (_, localHash) => localHash != s3Metadata.remoteHash }.
         map {
           case (localFile,_) => {
-            println(s"   Updated: ${c.relativePath(localFile)}")
+            logger.info(s"   Updated: ${c.relativePath(localFile)}")
             localFile
           }
         }