feat(e2b): use Filesystem REST API for native binary I/O

agentscope-extensions/agentscope-extensions-sandbox/agentscope-extensions-sandbox-e2b/src/main/java/io/agentscope/extensions/sandbox/e2b/E2bFilesystemSpec.java

@@ -124,4 +124,9 @@ protected SandboxSnapshotSpec snapshotSpec() {
     protected WorkspaceSpec workspaceSpec() {
         return defaultWorkspaceSpec;
     }
+
+    @Override
+    public E2bSandboxFilesystem createFilesystem() {
+        return new E2bSandboxFilesystem();
+    }
 }

agentscope-extensions/agentscope-extensions-sandbox/agentscope-extensions-sandbox-e2b/src/main/java/io/agentscope/extensions/sandbox/e2b/E2bSandbox.java

@@ -16,7 +16,6 @@
 package io.agentscope.extensions.sandbox.e2b;
 
 import com.fasterxml.jackson.databind.JsonNode;
-import com.fasterxml.jackson.databind.ObjectMapper;
 import io.agentscope.core.agent.RuntimeContext;
 import io.agentscope.harness.agent.sandbox.AbstractBaseSandbox;
 import io.agentscope.harness.agent.sandbox.ExecResult;
@@ -25,7 +24,7 @@
 import io.agentscope.harness.agent.sandbox.WorkspaceMountSupport;
 import java.io.ByteArrayInputStream;
 import java.io.InputStream;
-import java.util.Base64;
+import java.util.UUID;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
@@ -42,7 +41,6 @@ public class E2bSandbox extends AbstractBaseSandbox {
     private static final Logger log = LoggerFactory.getLogger(E2bSandbox.class);
 
     private static final int TAR_TIMEOUT_SECONDS = 300;
-    private static final int B64_CHUNK = 4000;
 
     private final E2bSandboxState e2bState;
     private final E2bSandboxClientOptions opt;
@@ -97,17 +95,42 @@ protected InputStream doPersistWorkspace() throws Exception {
             return new ByteArrayInputStream(E2bSnapshotRefs.encodeSnapshotId(id));
         }
         String root = e2bState.getWorkspaceRoot();
+        String tarPath = "/tmp/agentscope-ws-" + UUID.randomUUID() + ".tar";
         StringBuilder script = new StringBuilder("tar ");
         for (String ex :
                 WorkspaceMountSupport.tarExcludeArgsForBindMounts(e2bState.getWorkspaceSpec())) {
             script.append(ex).append(' ');
         }
-        script.append("-cf - -C ").append(shellSingleQuote(root)).append(" .");
-        String cmd = script.toString();
-        byte[] tar = envd().runShellBinaryStdout(e2bState, root, cmd, TAR_TIMEOUT_SECONDS);
+        script.append("-cf ")
+                .append(tarPath)
+                .append(" -C ")
+                .append(shellSingleQuote(root))
+                .append(" .");
+        envd().runShell(e2bState, root, script.toString(), TAR_TIMEOUT_SECONDS);
+        byte[] tar = downloadFile(tarPath);
         return new ByteArrayInputStream(tar);
     }
 
+    /**
+     * Upload a file to the sandbox filesystem via the E2B Filesystem REST API.
+     *
+     * @param remotePath absolute path in the sandbox
+     * @param data       file content
+     */
+    public void uploadFile(String remotePath, byte[] data) throws Exception {
+        envd().uploadFile(e2bState, remotePath, data);
+    }
+
+    /**
+     * Download a file from the sandbox filesystem via the E2B Filesystem REST API.
+     *
+     * @param remotePath absolute path in the sandbox
+     * @return file content
+     */
+    public byte[] downloadFile(String remotePath) throws Exception {
+        return envd().downloadFile(e2bState, remotePath);
+    }
+
     @Override
     protected void doHydrateWorkspace(InputStream archive) throws Exception {
         byte[] all = archive.readAllBytes();
@@ -116,29 +139,16 @@ protected void doHydrateWorkspace(InputStream archive) throws Exception {
             restoreSandboxFromSnapshotTemplate(nativeId);
             return;
         }
+        String tarPath = "/tmp/agentscope-ws-" + UUID.randomUUID() + ".tar";
+        envd().uploadFile(e2bState, tarPath, all);
         String root = e2bState.getWorkspaceRoot();
-        String b64 = Base64.getEncoder().encodeToString(all);
-        envd().runShell(e2bState, root, "rm -f /tmp/agentscope-ws.b64", 30);
-        ObjectMapper om = new ObjectMapper();
-        for (int i = 0; i < b64.length(); i += B64_CHUNK) {
-            String chunk = b64.substring(i, Math.min(b64.length(), i + B64_CHUNK));
-            String lit = om.writeValueAsString(chunk);
-            String py =
-                    "import pathlib; pathlib.Path('/tmp/agentscope-ws.b64').open('a').write("
-                            + lit
-                            + ")";
-            envd().runShell(e2bState, root, "python3 -c " + shellSingleQuote(py), 120);
+        StringBuilder script = new StringBuilder("tar ");
+        for (String ex :
+                WorkspaceMountSupport.tarExcludeArgsForBindMounts(e2bState.getWorkspaceSpec())) {
+            script.append(ex).append(' ');
         }
-        String pyFin =
-                "import base64,pathlib,subprocess; d="
-                        + om.writeValueAsString(root)
-                        + "; raw=base64.standard_b64decode(pathlib.Path('/tmp/agentscope-ws.b64').read_text());"
-                        + " subprocess.run(['tar','xf','-','-C',d],input=raw,check=True)";
-        envd().runShell(
-                        e2bState,
-                        root,
-                        "python3 -c " + shellSingleQuote(pyFin),
-                        TAR_TIMEOUT_SECONDS);
+        script.append("xf ").append(tarPath).append(" -C ").append(shellSingleQuote(root));
+        envd().runShell(e2bState, root, script.toString(), TAR_TIMEOUT_SECONDS);
     }
 
     @Override

agentscope-extensions/agentscope-extensions-sandbox/agentscope-extensions-sandbox-e2b/src/main/java/io/agentscope/extensions/sandbox/e2b/E2bSandboxFilesystem.java

@@ -0,0 +1,77 @@
+/*
+ * Copyright 2024-2026 the original author or authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package io.agentscope.extensions.sandbox.e2b;
+
+import io.agentscope.core.agent.RuntimeContext;
+import io.agentscope.harness.agent.filesystem.model.FileDownloadResponse;
+import io.agentscope.harness.agent.filesystem.model.FileUploadResponse;
+import io.agentscope.harness.agent.filesystem.sandbox.SandboxBackedFilesystem;
+import io.agentscope.harness.agent.sandbox.Sandbox;
+import java.util.ArrayList;
+import java.util.List;
+import java.util.Map;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+/**
+ * An E2B-optimized filesystem that uses the Filesystem REST API for upload/download, avoiding
+ * base64 overhead and the 512 KB output truncation of shell-based transfers.
+ */
+public class E2bSandboxFilesystem extends SandboxBackedFilesystem {
+
+    private static final Logger log = LoggerFactory.getLogger(E2bSandboxFilesystem.class);
+
+    @Override
+    public List<FileUploadResponse> uploadFiles(
+            RuntimeContext runtimeContext, List<Map.Entry<String, byte[]>> files) {
+        Sandbox s = getSandbox();
+        if (!(s instanceof E2bSandbox e2b)) {
+            return super.uploadFiles(runtimeContext, files);
+        }
+        List<FileUploadResponse> results = new ArrayList<>(files.size());
+        for (Map.Entry<String, byte[]> file : files) {
+            String path = file.getKey();
+            try {
+                e2b.uploadFile(path, file.getValue());
+                results.add(FileUploadResponse.success(path));
+            } catch (Exception e) {
+                log.warn("[e2b-sandbox-fs] upload failed for path: {}", path, e);
+                results.add(FileUploadResponse.fail(path, e.getMessage()));
+            }
+        }
+        return results;
+    }
+
+    @Override
+    public List<FileDownloadResponse> downloadFiles(
+            RuntimeContext runtimeContext, List<String> paths) {
+        Sandbox s = getSandbox();
+        if (!(s instanceof E2bSandbox e2b)) {
+            return super.downloadFiles(runtimeContext, paths);
+        }
+        List<FileDownloadResponse> results = new ArrayList<>(paths.size());
+        for (String path : paths) {
+            try {
+                byte[] content = e2b.downloadFile(path);
+                results.add(FileDownloadResponse.success(path, content));
+            } catch (Exception e) {
+                log.warn("[e2b-sandbox-fs] download failed for path: {}", path, e);
+                results.add(FileDownloadResponse.fail(path, e.getMessage()));
+            }
+        }
+        return results;
+    }
+}