Try not flooding the terminal with ignored errors...

...in updateClassifiers.

Also fail if an artifact cannot be fetched in update. A bit risky - might unveil locked errors, that ought to be circumvented.

build.sbt

@@ -226,6 +226,10 @@ lazy val cache = project
       import com.typesafe.tools.mima.core.ProblemFilters._
       
       Seq(
+        // Since 1.0.0-M11
+        // Add constructor parameter on FileError - shouldn't be built by users anyway
+        ProblemFilters.exclude[MissingMethodProblem]("coursier.FileError.this"),
+        ProblemFilters.exclude[MissingMethodProblem]("coursier.FileError#Recoverable.this"),
         // Since 1.0.0-M10
         // methods that should have been private anyway
         ProblemFilters.exclude[MissingMethodProblem]("coursier.TermDisplay.update"),

cache/src/main/scala/coursier/FileError.scala

@@ -2,26 +2,41 @@ package coursier
 
 import java.io.File
 
-sealed abstract class FileError(val message: String) extends Product with Serializable
+sealed abstract class FileError(
+  val `type`: String,
+  val message: String
+) extends Product with Serializable
 
 object FileError {
 
-  final case class DownloadError(reason: String) extends FileError(s"Download error: $reason")
+  final case class DownloadError(reason: String) extends FileError(
+    "download error",
+    reason
+  )
 
   final case class NotFound(
     file: String,
     permanent: Option[Boolean] = None
-  ) extends FileError(s"Not found: $file")
+  ) extends FileError(
+    "not found",
+    file
+  )
 
   final case class ChecksumNotFound(
     sumType: String,
     file: String
-  ) extends FileError(s"$sumType checksum not found: $file")
+  ) extends FileError(
+    "checksum not found",
+    file
+  )
 
   final case class ChecksumFormatError(
     sumType: String,
     file: String
-  ) extends FileError(s"Unrecognized $sumType checksum format in $file")
+  ) extends FileError(
+    "checksum format error",
+    file
+  )
 
   final case class WrongChecksum(
     sumType: String,
@@ -29,10 +44,22 @@ object FileError {
     expected: String,
     file: String,
     sumFile: String
-  ) extends FileError(s"$sumType checksum validation failed: $file")
+  ) extends FileError(
+    "wrong checksum",
+    file
+  )
 
-  sealed abstract class Recoverable(message: String) extends FileError(message)
-  final case class Locked(file: File) extends Recoverable(s"Locked: $file")
-  final case class ConcurrentDownload(url: String) extends Recoverable(s"Concurrent download: $url")
+  sealed abstract class Recoverable(
+    `type`: String,
+    message: String
+  ) extends FileError(`type`, message)
+  final case class Locked(file: File) extends Recoverable(
+    "locked",
+    file.toString
+  )
+  final case class ConcurrentDownload(url: String) extends Recoverable(
+    "concurrent download",
+    url
+  )
 
 }

plugin/src/main/scala-2.10/coursier/CoursierPlugin.scala

@@ -1,7 +1,5 @@
 package coursier
 
-import java.io.File
-
 import sbt._
 import sbt.Keys._
 
@@ -43,7 +41,7 @@ object CoursierPlugin extends AutoPlugin {
     coursierFallbackDependencies <<= Tasks.coursierFallbackDependenciesTask,
     coursierCache := Cache.default,
     update <<= Tasks.updateTask(withClassifiers = false),
-    updateClassifiers <<= Tasks.updateTask(withClassifiers = true),
+    updateClassifiers <<= Tasks.updateTask(withClassifiers = true, ignoreArtifactErrors = true),
     updateSbtClassifiers in Defaults.TaskGlobal <<= Tasks.updateTask(withClassifiers = true, sbtClassifiers = true),
     coursierProject <<= Tasks.coursierProjectTask,
     coursierProjects <<= Tasks.coursierProjectsTask,

plugin/src/main/scala-2.10/coursier/Settings.scala

@@ -4,7 +4,11 @@ import scala.util.{Failure, Success, Try}
 
 object Settings {
 
-  private val baseDefaultVerbosityLevel = 0
+  private lazy val baseDefaultVerbosityLevel =
+    if (System.console() == null) // non interactive mode
+      0
+    else
+      1
 
   def defaultVerbosityLevel: Int = {
 

plugin/src/main/scala-2.10/coursier/Tasks.scala

@@ -185,7 +185,11 @@ object Tasks {
       Module("org.scala-lang", "scalap") -> scalaVersion
     )
 
-  def updateTask(withClassifiers: Boolean, sbtClassifiers: Boolean = false) = Def.task {
+  def updateTask(
+    withClassifiers: Boolean,
+    sbtClassifiers: Boolean = false,
+    ignoreArtifactErrors: Boolean = false
+  ) = Def.task {
 
     def grouped[K, V](map: Seq[(K, V)]): Map[K, Seq[V]] =
       map.groupBy { case (k, _) => k }.map {
@@ -375,7 +379,7 @@ object Tasks {
             s"${dep.module}:${dep.version}:${dep.configuration}"
           }.sorted.distinct
 
-        if (verbosityLevel >= 1) {
+        if (verbosityLevel >= 2) {
           val repoReprs = repositories.map {
             case r: IvyRepository =>
               s"ivy:${r.pattern}"
@@ -396,7 +400,7 @@ object Tasks {
 
         if (verbosityLevel >= 0)
           log.info(s"Resolving ${currentProject.module.organization}:${currentProject.module.name}:${currentProject.version}")
-        if (verbosityLevel >= 1)
+        if (verbosityLevel >= 2)
           for (depRepr <- depsRepr(currentProject.dependencies))
             log.info(s"  $depRepr")
 
@@ -467,7 +471,7 @@ object Tasks {
 
         if (verbosityLevel >= 0)
           log.info("Resolution done")
-        if (verbosityLevel >= 1) {
+        if (verbosityLevel >= 2) {
           val finalDeps = Config.dependenciesWithConfig(
             res,
             depsByConfig.map { case (k, l) => k -> l.toSet },
@@ -532,18 +536,42 @@ object Tasks {
         if (verbosityLevel >= 0)
           log.info("Fetching artifacts: done")
 
-        def artifactFileOpt(artifact: Artifact) = {
-          val fileOrError = artifactFilesOrErrors.getOrElse(artifact, -\/("Not downloaded"))
+        val artifactFiles = artifactFilesOrErrors.collect {
+          case (artifact, \/-(file)) =>
+            artifact -> file
+        }
 
-          fileOrError match {
-            case \/-(file) =>
-              if (file.toString.contains("file:/"))
-                throw new Exception(s"Wrong path: $file")
-              Some(file)
-            case -\/(err) =>
-              log.error(s"${artifact.url}: $err")
-              None
+        val artifactErrors = artifactFilesOrErrors.toVector.collect {
+          case (_, -\/(err)) =>
+            err
+        }
+
+        if (artifactErrors.nonEmpty) {
+          val groupedArtifactErrors = artifactErrors
+            .groupBy(_.`type`)
+            .mapValues(_.map(_.message).sorted)
+            .toVector
+            .sortBy(_._1)
+
+          for ((type0, errors) <- groupedArtifactErrors) {
+            log.error(s"${errors.size} $type0")
+
+            if (!ignoreArtifactErrors || verbosityLevel >= 1)
+              for (err <- errors)
+                log.error("  " + err)
           }
+
+          if (!ignoreArtifactErrors)
+            throw new Exception(s"Encountered ${artifactErrors.length} errors (see above messages)")
+        }
+
+        def artifactFileOpt(artifact: Artifact) = {
+          val res = artifactFiles.get(artifact)
+
+          if (res.isEmpty)
+            log.error(s"${artifact.url} not downloaded (should not happen)")
+
+          res
         }
 
         writeIvyFiles()