Really close http connections

cache/src/main/scala/coursier/Cache.scala

@@ -31,6 +31,16 @@ trait AuthenticatedURLConnection extends URLConnection {
 
 object Cache {
 
+  private[coursier] def closeConn(conn: URLConnection): Unit = {
+    Try(conn.getInputStream).toOption.filter(_ != null).foreach(_.close())
+    conn match {
+      case conn0: HttpURLConnection =>
+        Try(conn0.getErrorStream).toOption.filter(_ != null).foreach(_.close())
+        conn0.disconnect()
+      case _ =>
+    }
+  }
+
   // java.nio.charset.StandardCharsets.UTF_8 not available in Java 6
   private val UTF_8 = Charset.forName("UTF-8")
 
@@ -398,12 +408,7 @@ object Cache {
     } catch {
       case NonFatal(e) =>
         if (conn != null)
-          conn match {
-            case conn0: HttpURLConnection =>
-              conn0.getInputStream.close()
-              conn0.disconnect()
-            case _ =>
-          }
+          closeConn(conn)
         throw e
     }
   }
@@ -448,11 +453,7 @@ object Cache {
       }
     } finally {
       if (conn != null)
-        conn match {
-          case conn0: HttpURLConnection =>
-            conn0.disconnect()
-          case _ =>
-        }
+        closeConn(conn)
     }
   }
 
@@ -535,11 +536,7 @@ object Cache {
             }
           } finally {
             if (conn != null)
-              conn match {
-                case conn0: HttpURLConnection =>
-                  conn0.disconnect()
-                case _ =>
-              }
+              closeConn(conn)
           }
         }
       }
@@ -673,8 +670,7 @@ object Cache {
 
                       ackRange.startsWith(s"bytes $alreadyDownloaded-") || {
                         // unrecognized Content-Range header -> start a new connection with no resume
-                        conn0.getInputStream.close()
-                        conn0.disconnect()
+                        closeConn(conn)
                         conn = urlConnection(url, artifact.authentication)
                         false
                       }
@@ -719,11 +715,7 @@ object Cache {
                 }
               } finally {
                 if (conn != null)
-                  conn match {
-                    case conn0: HttpURLConnection =>
-                      conn0.disconnect()
-                    case _ =>
-                  }
+                  closeConn(conn)
               }
             }
 

cli/src/main/scala-2.11/coursier/cli/scaladex/Scaladex.scala

@@ -45,7 +45,7 @@ object Scaladex {
           coursier.Platform.readFullySync(conn.getInputStream)
         } finally {
           if (conn != null)
-            conn.disconnect()
+            coursier.Cache.closeConn(conn)
         }
 
         new String(b, StandardCharsets.UTF_8).right[String]

project/HttpUtil.scala

@@ -44,8 +44,11 @@ object HttpUtil {
       } finally {
         if (is != null)
           is.close()
-        if (httpConn != null)
+        if (httpConn != null) {
+          scala.util.Try(httpConn.getInputStream).filter(_ != null).foreach(_.close())
+          scala.util.Try(httpConn.getErrorStream).filter(_ != null).foreach(_.close())
           httpConn.disconnect()
+        }
       }
     }
 

sbt-coursier/src/main/scala/coursier/FallbackDependenciesRepository.scala

@@ -38,7 +38,7 @@ object FallbackDependenciesRepository {
             None
         } finally {
           if (conn != null)
-            conn.disconnect()
+            coursier.Cache.closeConn(conn)
         }
       case _ =>
         None
@@ -55,10 +55,8 @@ object FallbackDependenciesRepository {
         case _: IOException =>
           false
       } finally {
-        conn match {
-          case conn0: HttpURLConnection => conn0.disconnect()
-          case _ =>
-        }
+        if (conn != null)
+          coursier.Cache.closeConn(conn)
       }
     }
   }