Merge pull request #46 from goblint/server-recovery

Recover Goblint server automatically after crashing

pom.xml

@@ -70,6 +70,13 @@
             <version>3.1.1.RELEASE</version>
         </dependency>
 
+        <!-- https://mvnrepository.com/artifact/io.methvin/directory-watcher -->
+        <dependency>
+            <groupId>io.methvin</groupId>
+            <artifactId>directory-watcher</artifactId>
+            <version>0.17.1</version>
+        </dependency>
+
 
         <!-- log4j -->
         <dependency>

src/main/java/Main.java

@@ -102,7 +102,12 @@ private static void addAnalysis() {
         GoblintService goblintService = localEndpoint.getServer();
 
         // read Goblint configurations
-        goblintService.read_config(new Params(new File(goblintServer.getGoblintConf()).getAbsolutePath()));
+        goblintService.read_config(new Params(new File(goblintServer.getGoblintConf()).getAbsolutePath()))
+                .whenComplete((res, ex) -> {
+                    String msg = "Goblint was unable to successfully read the new configuration. " + ex.getMessage();
+                    magpieServer.forwardMessageToClient(new MessageParams(MessageType.Warning, msg));
+                    log.error(msg);
+                });
 
         // add analysis to the MagpieServer
         ServerAnalysis serverAnalysis = new GoblintAnalysis(magpieServer, goblintServer, goblintService, gobpieConfiguration);

src/main/java/analysis/GoblintAnalysis.java

@@ -1,9 +1,7 @@
 package analysis;
 
 import api.GoblintService;
-import api.messages.GoblintFunctionsResult;
-import api.messages.GoblintMessagesResult;
-import api.messages.Params;
+import api.messages.*;
 import com.ibm.wala.classLoader.Module;
 import goblintserver.GoblintServer;
 import gobpie.GobPieConfiguration;
@@ -101,7 +99,11 @@ public void analyze(Collection<? extends Module> files, AnalysisConsumer consume
                 server.consume(new ArrayList<>(response), source());
                 log.info("--------------------- Analysis finished ----------------------");
             }).exceptionally(ex -> {
-                log.info(ex.getMessage());
+                // TODO: handle closed socket exceptions:
+                //      org.eclipse.lsp4j.jsonrpc.JsonRpcException: java.net.SocketException: Broken pipe; errno=32
+                //  and org.eclipse.lsp4j.jsonrpc.JsonRpcException: org.newsclub.net.unix.SocketClosedException: Not open
+                log.error("--------------------- Analysis failed  ----------------------");
+                log.error(ex.getMessage());
                 return null;
             });
         }
@@ -150,37 +152,60 @@ private void preAnalyse() {
         }
     }
 
-
     /**
      * Sends the requests to Goblint server and gets their results.
+     * Checks if analysis succeeded.
+     * If analysis succeeds, requests the messages from the Goblint server.
+     * If showCfg option is turned on, asks for the function names for code lenses.
      *
      * @return a CompletableFuture of a collection of warning messages and cfg code lenses if request was successful.
      * @throws GobPieException in case the analysis was aborted or returned a VerifyError.
      */
 
     private CompletableFuture<Collection<AnalysisResult>> reanalyse() {
-
         return goblintService.analyze(new Params())
-                .thenCompose(analysisResult -> {
-                    // Make sure that analysis succeeded
-                    if (analysisResult.getStatus().contains("Aborted"))
-                        throw new GobPieException("The running analysis has been aborted.", GobPieExceptionType.GOBLINT_EXCEPTION);
-                    else if (analysisResult.getStatus().contains("VerifyError"))
-                        throw new GobPieException("Analysis returned VerifyError.", GobPieExceptionType.GOBLINT_EXCEPTION);
-                    // Get warning messages
-                    CompletableFuture<List<GoblintMessagesResult>> messagesTask = goblintService.messages();
-                    if (gobpieConfiguration.getshowCfg() != null && gobpieConfiguration.getshowCfg()) {
-                        // Get list of functions
-                        CompletableFuture<List<GoblintFunctionsResult>> functionsTask = goblintService.functions();
-                        return messagesTask.thenCombine(functionsTask, (messages, functions) ->
-                                Stream.concat(
-                                                convertMessagesFromJson(messages).stream(),
-                                                convertFunctionsFromJson(functions).stream())
-                                        .collect(Collectors.toList()));
-                    }
-                    return messagesTask.thenApply(this::convertMessagesFromJson);
-                });
+                .thenCompose(this::getComposedAnalysisResults)
+                .applyToEither(didGoblintCrash(), res -> res);
+    }
 
+    private void didAnalysisNotSucceed(GoblintAnalysisResult analysisResult) {
+        if (analysisResult.getStatus().contains("Aborted"))
+            throw new GobPieException("The running analysis has been aborted.", GobPieExceptionType.GOBLINT_EXCEPTION);
+        else if (analysisResult.getStatus().contains("VerifyError"))
+            throw new GobPieException("Analysis returned VerifyError.", GobPieExceptionType.GOBLINT_EXCEPTION);
+    }
+
+    private CompletableFuture<Collection<AnalysisResult>> didGoblintCrash() {
+        return CompletableFuture.supplyAsync(() -> {
+            try {
+                goblintServer.getGoblintRunProcess().getProcess().waitFor();
+            } catch (InterruptedException ignored) {
+            }
+            throw new GobPieException("Goblint has exited.", GobPieExceptionType.GOBLINT_EXCEPTION);
+        });
+    }
+
+    private CompletableFuture<Collection<AnalysisResult>> convertAndCombineResults(
+            CompletableFuture<List<GoblintMessagesResult>> messagesCompletableFuture,
+            CompletableFuture<List<GoblintFunctionsResult>> functionsCompletableFuture) {
+        return messagesCompletableFuture
+                .thenCombine(functionsCompletableFuture, (messages, functions) ->
+                        Stream.concat(
+                                convertMessagesFromJson(messages).stream(),
+                                convertFunctionsFromJson(functions).stream()
+                        ).collect(Collectors.toList()));
+    }
+
+    private CompletableFuture<Collection<AnalysisResult>> getComposedAnalysisResults(GoblintAnalysisResult analysisResult) {
+        didAnalysisNotSucceed(analysisResult);
+        // Get warning messages
+        CompletableFuture<List<GoblintMessagesResult>> messagesCompletableFuture = goblintService.messages();
+        if (gobpieConfiguration.getshowCfg() == null || !gobpieConfiguration.getshowCfg()) {
+            return messagesCompletableFuture.thenApply(this::convertMessagesFromJson);
+        }
+        // Get list of functions
+        CompletableFuture<List<GoblintFunctionsResult>> functionsCompletableFuture = goblintService.functions();
+        return convertAndCombineResults(messagesCompletableFuture, functionsCompletableFuture);
     }
 
 
@@ -229,15 +254,22 @@ public ProcessResult runCommand(File dirPath, String[] command) throws IOExcepti
      */
 
     public FileAlterationObserver createGoblintConfObserver() {
-
         FileFilter fileFilter = file -> file.getName().equals(gobpieConfiguration.getGoblintConf());
-
         FileAlterationObserver observer = new FileAlterationObserver(System.getProperty("user.dir"), fileFilter);
         observer.addListener(new FileAlterationListenerAdaptor() {
             @Override
             public void onFileChange(File file) {
-                goblintService.reset_config();
-                goblintService.read_config(new Params(new File(goblintServer.getGoblintConf()).getAbsolutePath()));
+                if (!goblintServer.getGoblintRunProcess().getProcess().isAlive()) {
+                    magpieServer.exit();
+                } else {
+                    goblintService.reset_config();
+                    goblintService.read_config(new Params(new File(goblintServer.getGoblintConf()).getAbsolutePath()))
+                            .whenComplete((res, ex) -> {
+                                String msg = "Goblint was unable to successfully read the new configuration. " + ex.getMessage();
+                                magpieServer.forwardMessageToClient(new MessageParams(MessageType.Warning, msg));
+                                log.error(msg);
+                            });
+                }
             }
         });
 

src/main/java/api/GoblintService.java

@@ -19,45 +19,39 @@
 
 public interface GoblintService {
 
-    // Examples of requests used in this project:
-    // {"jsonrpc":"2.0","id":0,"method":"read_config","params":{"fname":"goblint.json"}}
-    // {"jsonrpc":"2.0","id":0,"method":"analyze","params":{}}
-    // {"jsonrpc":"2.0","id":0,"method":"messages"}
-    // {"jsonrpc":"2.0","id":0,"method":"functions"}
-    // {"jsonrpc":"2.0","id":0,"method":"cfg", "params":{"fname":"main"}}
-    // {"jsonrpc":"2.0","id":0,"method":"node_state","params":{"nid":"fun2783"}}
-
-    // Examples of responses for the requests:
-    // method: "analyze" response:
-    // {"id":0,"jsonrpc":"2.0","result":{"status":["Success"]}}
-    // method: "messages" response:
-    // {"id":0,"jsonrpc":"2.0","result":[{"tags":[{"Category":["Race"]}], ... }]}
-    // method: "functions" response:
-    // {"id":0,"jsonrpc":"2.0","result":[{"funName":"qsort","location":{"file":"/home/ ... }]}
-    // method: "cfg" response:
-    // {"id":0,"jsonrpc":"2.0","result":{"cfg":"digraph cfg {\n\tnode [id=\"\\N\", ... }}
-
     @JsonRequest
     CompletableFuture<JsonObject> ping();
 
+    // request:  {"jsonrpc":"2.0","id":0,"method":"analyze","params":{}}
+    // response: {"id":0,"jsonrpc":"2.0","result":{"status":["Success"]}}
     @JsonRequest
     CompletableFuture<GoblintAnalysisResult> analyze(Params params);
 
+    // request:  {"jsonrpc":"2.0","id":0,"method":"messages"}
+    // response: {"id":0,"jsonrpc":"2.0","result":[{"tags":[{"Category":["Race"]}], ... }]}
     @JsonRequest
     CompletableFuture<List<GoblintMessagesResult>> messages();
 
+    // request:  {"jsonrpc":"2.0","id":0,"method":"functions"}
+    // response: {"id":0,"jsonrpc":"2.0","result":[{"funName":"qsort","location":{"file":"/home/ ... }]}
     @JsonRequest
     CompletableFuture<List<GoblintFunctionsResult>> functions();
 
+    // request:  {"jsonrpc":"2.0","id":0,"method":"cfg", "params":{"fname":"main"}}
+    // response: {"id":0,"jsonrpc":"2.0","result":{"cfg":"digraph cfg {\n\tnode [id=\"\\N\", ... }}
     @JsonRequest
     CompletableFuture<GoblintCFGResult> cfg(Params params);
 
+    // request:  {"jsonrpc":"2.0","id":0,"method":"node_state","params":{"nid":"fun2783"}}
     @JsonRequest
     CompletableFuture<List<JsonObject>> node_state(GobPieHttpHandler.NodeParams params);
 
     @JsonRequest
     CompletableFuture<Void> reset_config();
 
+    // request:  {"jsonrpc":"2.0","id":0,"method":"read_config","params":{"fname":"goblint.json"}}
+    // response: {"id":0,"jsonrpc":"2.0","result":null}
+    //           {"id":0,"jsonrpc":"2.0","error":{"code":-32603,"message":"Json_encoding: Unexpected object field .."}}
     @JsonRequest
     CompletableFuture<Void> read_config(Params params);
 

src/main/java/api/GoblintServiceLauncher.java

@@ -127,7 +127,7 @@ protected RemoteEndpoint createRemoteEndpoint(MessageJsonHandler messageJsonHand
 
         public void connectSocketStreams() {
             try {
-                AFUNIXSocket socket = AFUNIXSocket.newInstance();
+                AFUNIXSocket socket = AFUNIXSocket.newInstance(); // TODO: close after
                 socket.connect(AFUNIXSocketAddress.of(new File(goblintSocketName)));
                 outputStream = socket.getOutputStream();
                 inputStream = socket.getInputStream();

src/main/java/api/util/DirectoryWatchingUtility.java

@@ -0,0 +1,44 @@
+package api.util;
+
+import io.methvin.watcher.DirectoryWatcher;
+
+import java.io.IOException;
+import java.nio.file.Path;
+import java.util.concurrent.CompletableFuture;
+
+public class DirectoryWatchingUtility {
+
+    private final DirectoryWatcher watcher;
+
+    public DirectoryWatchingUtility(Path directoryToWatch) throws IOException {
+        this.watcher = DirectoryWatcher.builder()
+                .path(directoryToWatch) // or use paths(directoriesToWatch)
+                .listener(event -> {
+                    switch (event.eventType()) {
+                        case CREATE:
+                            /* file created */
+                            stopWatching();
+                            return;
+                        case MODIFY:
+                            /* file modified */
+                            break;
+                        case DELETE:
+                            /* file deleted */
+                            break;
+                    }
+                })
+                // .fileHashing(false) // defaults to true
+                // .logger(logger) // defaults to LoggerFactory.getLogger(DirectoryWatcher.class)
+                // .watchService(watchService) // defaults based on OS to either JVM WatchService or the JNA macOS WatchService
+                .build();
+    }
+
+    public void stopWatching() throws IOException {
+        watcher.close();
+    }
+
+    public CompletableFuture<Void> watch() {
+        // you can also use watcher.watch() to block the current thread
+        return watcher.watchAsync();
+    }
+}

src/main/java/goblintserver/GoblintServer.java

@@ -1,5 +1,6 @@
 package goblintserver;
 
+import api.util.DirectoryWatchingUtility;
 import gobpie.GobPieException;
 import magpiebridge.core.MagpieServer;
 import org.apache.logging.log4j.LogManager;
@@ -15,6 +16,7 @@
 import java.io.IOException;
 import java.nio.file.*;
 import java.util.Arrays;
+import java.util.concurrent.CompletableFuture;
 import java.util.concurrent.TimeoutException;
 
 import static gobpie.GobPieExceptionType.GOBLINT_EXCEPTION;
@@ -86,30 +88,25 @@ public void startGoblintServer() {
         try {
             // run command to start goblint
             log.info("Goblint run with command: " + String.join(" ", goblintRunCommand));
-
             goblintRunProcess = runCommand(new File(System.getProperty("user.dir")), goblintRunCommand);
 
             // wait until Goblint socket is created before continuing
             if (!new File(goblintSocket).exists()) {
-                WatchService watchService = FileSystems.getDefault().newWatchService();
-                Path path = Paths.get(System.getProperty("user.dir"));
-                path.register(watchService, StandardWatchEventKinds.ENTRY_CREATE);
-                WatchKey key;
-                while ((key = watchService.take()) != null) {
-                    for (WatchEvent<?> event : key.pollEvents()) {
-                        if ((event.context()).equals(Paths.get(goblintSocket))) {
-                            log.info("Goblint server started.");
-                            return;
-                        }
-                    }
-                    key.reset();
-                }
+                watch();
             }
         } catch (IOException | InvalidExitValueException | InterruptedException | TimeoutException e) {
             throw new GobPieException("Running Goblint failed.", e, GOBLINT_EXCEPTION);
         }
     }
 
+    private void watch() throws IOException, InterruptedException {
+        Path path = Paths.get(System.getProperty("user.dir"));
+        DirectoryWatchingUtility socketWatchingUtility = new DirectoryWatchingUtility(path);
+        socketWatchingUtility.watch().thenAccept(res -> {
+            log.info("Goblint server started.");
+        });
+    }
+
 
     /**
      * Method for running a command.
@@ -131,6 +128,8 @@ public void afterStop(Process process) {
                     magpieServer.forwardMessageToClient(new MessageParams(MessageType.Error, "Goblint server exited due to an error. Please check the output terminal of GobPie extension for more information."));
                     log.error("Goblint server exited due to an error (code: " + process.exitValue() + "). Please fix the issue reported above and restart the extension.");
                 }
+                magpieServer.cleanUp();
+                // TODO: throw an exception? where (and how) can it be caught to be handled though?
             }
         };