Hash copied files (#2055)

* Fix session label when reuse is not supported but requested

* Hash copied files

* restore import

* add file mode to the checksum

* Mock TestcontainersConfiguration

* checksum folders too

Author: bsideup

core/src/main/java/org/testcontainers/containers/GenericContainer.java

@@ -29,6 +29,7 @@
 import org.apache.commons.compress.archivers.tar.TarArchiveInputStream;
 import org.apache.commons.compress.archivers.tar.TarArchiveOutputStream;
 import org.apache.commons.compress.utils.IOUtils;
+import org.apache.commons.io.FileUtils;
 import org.apache.commons.lang.StringUtils;
 import org.jetbrains.annotations.NotNull;
 import org.jetbrains.annotations.Nullable;
@@ -75,6 +76,7 @@
 import java.lang.reflect.Method;
 import java.lang.reflect.UndeclaredThrowableException;
 import java.nio.charset.Charset;
+import java.nio.file.Files;
 import java.nio.file.Path;
 import java.time.Duration;
 import java.time.Instant;
@@ -87,6 +89,7 @@
 import java.util.LinkedHashSet;
 import java.util.List;
 import java.util.Map;
+import java.util.Map.Entry;
 import java.util.Optional;
 import java.util.Set;
 import java.util.concurrent.ExecutionException;
@@ -96,6 +99,8 @@
 import java.util.function.Consumer;
 import java.util.stream.Collectors;
 import java.util.stream.Stream;
+import java.util.zip.Adler32;
+import java.util.zip.Checksum;
 
 import static com.google.common.collect.Lists.newArrayList;
 import static org.testcontainers.utility.CommandLine.runShellCommand;
@@ -116,6 +121,8 @@ public class GenericContainer<SELF extends GenericContainer<SELF>>
 
     static final String HASH_LABEL = "org.testcontainers.hash";
 
+    static final String COPIED_FILES_HASH_LABEL = "org.testcontainers.copied_files.hash";
+
     /*
      * Default settings
      */
@@ -353,6 +360,11 @@ private void tryStart(Instant startedAt) {
                 }
 
                 if (TestcontainersConfiguration.getInstance().environmentSupportsReuse()) {
+                    createCommand.getLabels().put(
+                        COPIED_FILES_HASH_LABEL,
+                        Long.toHexString(hashCopiedFiles().getValue())
+                    );
+
                     String hash = hash(createCommand);
 
                     containerId = findContainerForReuse(hash).orElse(null);
@@ -381,7 +393,7 @@ private void tryStart(Instant startedAt) {
             if (!reused) {
                 containerId = createCommand.exec().getId();
 
-                // TODO add to the hash
+                // TODO use single "copy" invocation (and calculate an hash of the resulting tar archive)
                 copyToFileContainerPathMap.forEach(this::copyFileToContainer);
             }
 
@@ -474,6 +486,36 @@ private void tryStart(Instant startedAt) {
         }
     }
 
+    @VisibleForTesting
+    Checksum hashCopiedFiles() {
+        Checksum checksum = new Adler32();
+        copyToFileContainerPathMap.entrySet().stream().sorted(Entry.comparingByValue()).forEach(entry -> {
+            byte[] pathBytes = entry.getValue().getBytes();
+            // Add path to the hash
+            checksum.update(pathBytes, 0, pathBytes.length);
+
+            File file = new File(entry.getKey().getResolvedPath());
+            checksumFile(file, checksum);
+        });
+        return checksum;
+    }
+
+    @VisibleForTesting
+    @SneakyThrows(IOException.class)
+    void checksumFile(File file, Checksum checksum) {
+        Path path = file.toPath();
+        checksum.update(MountableFile.getUnixFileMode(path));
+        if (file.isDirectory()) {
+            try (Stream<Path> stream = Files.walk(path)) {
+                stream.filter(it -> it != path).forEach(it -> {
+                    checksumFile(it.toFile(), checksum);
+                });
+            }
+        } else {
+            FileUtils.checksum(file, checksum);
+        }
+    }
+
     @UnstableAPI
     @SneakyThrows(JsonProcessingException.class)
     final String hash(CreateContainerCmd createCommand) {
@@ -708,7 +750,7 @@ private void applyConfiguration(CreateContainerCmd createCommand) {
 
         Set<Link> allLinks = new HashSet<>();
         Set<String> allLinkedContainerNetworks = new HashSet<>();
-        for (Map.Entry<String, LinkableContainer> linkEntries : linkedContainers.entrySet()) {
+        for (Entry<String, LinkableContainer> linkEntries : linkedContainers.entrySet()) {
 
             String alias = linkEntries.getKey();
             LinkableContainer linkableContainer = linkEntries.getValue();

core/src/main/java/org/testcontainers/utility/MountableFile.java

@@ -9,6 +9,7 @@
 import org.apache.commons.lang.SystemUtils;
 import org.jetbrains.annotations.NotNull;
 import org.testcontainers.DockerClientFactory;
+import org.testcontainers.UnstableAPI;
 import org.testcontainers.images.builder.Transferable;
 
 import java.io.File;
@@ -361,9 +362,13 @@ private int getUnixFileMode(final String pathAsString) {
         if (this.forcedFileMode != null) {
             return this.getModeValue(path);
         }
+        return getUnixFileMode(path);
+    }
 
+    @UnstableAPI
+    public static int getUnixFileMode(final Path path) {
         try {
-            return (int) Files.getAttribute(path, "unix:mode");
+            return (int) Files.readAttributes(path, "unix:mode").get("mode");
         } catch (IOException | UnsupportedOperationException e) {
             // fallback for non-posix environments
             int mode = DEFAULT_FILE_MODE;