PrintStream reference counting

Fixes fabric8io#652.
hwellmann · Dec 21, 2016 · 100b77a · 100b77a
1 parent f727f85
commit 100b77a
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Showing 9 changed files with 274 additions and 54 deletions.
diff --git a/src/main/java/io/fabric8/maven/docker/StartMojo.java b/src/main/java/io/fabric8/maven/docker/StartMojo.java
@@ -484,6 +484,11 @@ public void log(int type, Timestamp timestamp, String txt) throws LogCallback.Do
                         public void error(String error) {
                             log.error("%s", error);
                         }
+
+                        @Override
+                        public void close() {
+                            // empty
+                        }
                     });
                     first = false;
                 }

diff --git a/src/main/java/io/fabric8/maven/docker/access/hc/DockerAccessWithHcClient.java b/src/main/java/io/fabric8/maven/docker/access/hc/DockerAccessWithHcClient.java
@@ -6,7 +6,6 @@
 import static java.net.HttpURLConnection.HTTP_NOT_MODIFIED;
 import static java.net.HttpURLConnection.HTTP_NO_CONTENT;
 import static java.net.HttpURLConnection.HTTP_OK;
-import static io.fabric8.maven.docker.log.LogCallbackFactory.createLogCallback;
 
 import java.io.File;
 import java.io.FileNotFoundException;
@@ -20,7 +19,6 @@
 import java.util.List;
 import java.util.Map;
 
-import io.fabric8.maven.docker.access.hc.util.ClientBuilder;
 import org.apache.http.HttpResponse;
 import org.apache.http.client.HttpResponseException;
 import org.apache.http.client.ResponseHandler;
@@ -40,6 +38,7 @@
 import io.fabric8.maven.docker.access.hc.ApacheHttpClientDelegate.HttpBodyAndStatus;
 import io.fabric8.maven.docker.access.hc.http.HttpClientBuilder;
 import io.fabric8.maven.docker.access.hc.unix.UnixSocketClientBuilder;
+import io.fabric8.maven.docker.access.hc.util.ClientBuilder;
 import io.fabric8.maven.docker.access.hc.win.NamedPipeClientBuilder;
 import io.fabric8.maven.docker.access.log.LogCallback;
 import io.fabric8.maven.docker.access.log.LogGetHandle;
@@ -146,7 +145,7 @@ public void startExecContainer(String containerId, LogOutputSpec outputSpec) thr
     }
 
     private ResponseHandler<Object> createExecResponseHandler(LogOutputSpec outputSpec) throws FileNotFoundException {
-        final LogCallback callback = createLogCallback(outputSpec);
+        final LogCallback callback = new DefaultLogCallback(outputSpec);
         return new ResponseHandler<Object>() {
             @Override
             public Object handleResponse(HttpResponse response) throws IOException {
@@ -159,6 +158,8 @@ public Object handleResponse(HttpResponse response) throws IOException {
                         }
                     } catch (LogCallback.DoneException e) {
                         // Ok, we stop here ...
+                    } finally {
+                        callback.close();
                     }
                 }
                 return null;

diff --git a/src/main/java/io/fabric8/maven/docker/access/log/LogCallback.java b/src/main/java/io/fabric8/maven/docker/access/log/LogCallback.java
@@ -42,6 +42,8 @@ public interface LogCallback {
      * @param error error description
      */
     void error(String error);
+
+    void close();
 
     /**
      * Exception indicating that logging is done and should be finished

diff --git a/src/main/java/io/fabric8/maven/docker/access/log/LogRequestor.java b/src/main/java/io/fabric8/maven/docker/access/log/LogRequestor.java
@@ -91,6 +91,8 @@ public void fetchLogs() {
             parseResponse(resp);
         } catch (IOException exp) {
             callback.error(exp.getMessage());
+        } finally {
+            callback.close();
         }
     }
 
@@ -105,6 +107,7 @@ public void run() {
         } catch (IOException exp) {
             callback.error("IO Error while requesting logs: " + exp);
         } finally {
+            callback.close();
             try {
                 synchronized (lock) {
                     client.close();
@@ -224,6 +227,7 @@ public void finish() {
                 }
             }
         }
+        callback.close();
     }
 
     @Override

diff --git a/src/main/java/io/fabric8/maven/docker/log/DefaultLogCallback.java b/src/main/java/io/fabric8/maven/docker/log/DefaultLogCallback.java
@@ -16,7 +16,10 @@
  */
 
 import java.io.FileNotFoundException;
+import java.io.FileOutputStream;
 import java.io.PrintStream;
+import java.util.HashMap;
+import java.util.Map;
 
 import io.fabric8.maven.docker.access.log.LogCallback;
 import io.fabric8.maven.docker.util.Timestamp;
@@ -27,24 +30,61 @@
  */
 public class DefaultLogCallback implements LogCallback {
 
+    private static Map<String, SharedPrintStream> printStreamMap = new HashMap<>();
+
     private final LogOutputSpec outputSpec;
-    private final PrintStream ps;
+    private final SharedPrintStream sps;
 
-    public DefaultLogCallback(LogOutputSpec outputSpec, PrintStream ps) throws FileNotFoundException {
+    public DefaultLogCallback(LogOutputSpec outputSpec) throws FileNotFoundException {
         this.outputSpec = outputSpec;
-        this.ps = ps;
+        this.sps = createOrReusePrintStream(outputSpec);
+    }
+
+    private synchronized SharedPrintStream createOrReusePrintStream(LogOutputSpec spec) throws FileNotFoundException {
+        String file = spec.getFile();
+        if (spec.isLogStdout() || file == null) {
+            return new SharedPrintStream(System.out);
+        }
+        SharedPrintStream sps = printStreamMap.get(file);
+        if (sps == null) {
+            PrintStream ps = new PrintStream(new FileOutputStream(file), true);
+            sps = new SharedPrintStream(ps);
+
+            printStreamMap.put(file, sps);
+        }
+        else {
+            sps.allocate();
+        }
+        return sps;
+    }
+
+    private PrintStream ps() {
+        return sps.getPrintStream();
     }
 
     @Override
     public void log(int type, Timestamp timestamp, String txt) {
-        addLogEntry(ps, new LogEntry(type, timestamp, txt));
+        addLogEntry(ps(), new LogEntry(type, timestamp, txt));
     }
 
     @Override
     public void error(String error) {
-        ps.println(error);
+        ps().println(error);
     }
 
+    @Override
+    public synchronized void close() {
+        sps.free();
+        if (!sps.isUsed()) {
+            if (sps.getPrintStream() != System.out) {
+                sps.getPrintStream().close();
+            }
+            String file = outputSpec.getFile();
+            if (file != null) {
+                printStreamMap.remove(file);
+            }
+        }
+    }
     private void addLogEntry(PrintStream ps, LogEntry logEntry) {
         // TODO: Add the entry to a queue, and let the queue be picked up with a small delay from an extra
         // thread which then can sort the entries by time before printing it out in order to avoid race conditions.
@@ -86,4 +126,5 @@ public int compareTo(LogEntry entry) {
             return timestamp.compareTo(entry.timestamp);
         }
     }
+
 }
diff --git a/src/main/java/io/fabric8/maven/docker/log/LogCallbackFactory.java b/src/main/java/io/fabric8/maven/docker/log/LogCallbackFactory.java
diff --git a/src/main/java/io/fabric8/maven/docker/log/LogDispatcher.java b/src/main/java/io/fabric8/maven/docker/log/LogDispatcher.java
@@ -15,11 +15,9 @@
  * limitations under the License.
  */
 
-import static io.fabric8.maven.docker.log.LogCallbackFactory.createLogCallback;
-import static io.fabric8.maven.docker.log.LogCallbackFactory.closeLogs;
-
 import java.io.FileNotFoundException;
-import java.util.*;
+import java.util.HashMap;
+import java.util.Map;
 
 import io.fabric8.maven.docker.access.DockerAccess;
 import io.fabric8.maven.docker.access.log.LogGetHandle;
@@ -40,16 +38,15 @@ public LogDispatcher(DockerAccess dockerAccess) {
     }
 
     public synchronized void trackContainerLog(String containerId, LogOutputSpec spec) throws FileNotFoundException {
-        LogGetHandle handle = dockerAccess.getLogAsync(containerId, createLogCallback(spec));
+        LogGetHandle handle = dockerAccess.getLogAsync(containerId, new DefaultLogCallback(spec));
         logHandles.put(containerId, handle);
     }
 
     public synchronized void fetchContainerLog(String containerId, LogOutputSpec spec) throws FileNotFoundException {
-        dockerAccess.getLogSync(containerId, createLogCallback(spec));
+        dockerAccess.getLogSync(containerId, new DefaultLogCallback(spec));
     }
 
     public synchronized void untrackAllContainerLogs() {
-        closeLogs();
         for (String key : logHandles.keySet()) {
             LogGetHandle handle = logHandles.get(key);
             handle.finish();

diff --git a/src/main/java/io/fabric8/maven/docker/log/SharedPrintStream.java b/src/main/java/io/fabric8/maven/docker/log/SharedPrintStream.java
@@ -0,0 +1,35 @@
+package io.fabric8.maven.docker.log;
+
+import java.io.PrintStream;
+
+class SharedPrintStream {
+    private PrintStream printStream;
+
+    private int numUsers;
+
+    public SharedPrintStream(PrintStream ps) {
+        this.printStream = ps;
+        this.numUsers = 1;
+    }
+
+    public PrintStream getPrintStream() {
+        return printStream;
+    }
+
+    public void setPrintStream(PrintStream printStream) {
+        this.printStream = printStream;
+    }
+
+    public boolean isUsed() {
+        return numUsers > 0;
+    }
+
+    public void allocate() {
+        numUsers++;
+    }
+
+    public void free() {
+        assert numUsers > 0;
+        numUsers--;
+    }
+}