test: add sandbox tool

Add a sandbox tool to run experiments and to do quick checks.

Signed-off-by: Pablo Barbáchano <[email protected]>

tests/README.md

@@ -306,7 +306,6 @@ can examine local variables and the stack, and can use the normal Python REPL.
 
 ```sh
 ./tools/devtool -y shell --privileged
-pip3 install ipython
 export PYTEST_ADDOPTS=--pdbcls=IPython.terminal.debugger:TerminalPdb
 ./tools/test.sh -k 1024 integration_tests/performance/test_boottime.py::test_boottime
 ```
@@ -378,3 +377,19 @@ ipdb> test_microvm.help.gdbserver()
 ```
 
 You get some instructions on how to run GDB to attach to gdbserver.
+
+## Sandbox
+
+```sh
+./tools/devtool sandbox
+```
+
+That should drop you in an IPython REPL, where you can interact with a microvm:
+
+```python
+uvm.help.print_log()
+uvm.get_all_metrics()
+uvm.ssh.run("ls")
+snap = uvm.snapshot_full()
+uvm.help.tmux_ssh()
+```

tools/devtool

@@ -414,6 +414,9 @@ cmd_help() {
     cat <<EOF
     test_debug [-- [<pytest args>]]
         Run tests in a debugging environment
+
+    test_sandbox
+        Run Firecracker in an IPython REPL
 EOF
 }
 
@@ -704,6 +707,10 @@ cmd_sh() {
         bash --norc -c "$*"
 }
 
+cmd_sandbox() {
+    cmd_sh "tmux new env PYTEST_ADDOPTS=--pdbcls=IPython.terminal.debugger:TerminalPdb PYTHONPATH=tests IPYTHONDIR=\$PWD/.ipython ipython -i ./tools/sandbox.py"
+}
+
 cmd_test_debug() {
     cmd_sh "tmux new ./tools/test.sh --pdb $@"
 }

tools/sandbox.py

@@ -0,0 +1,67 @@
+#!/usr/bin/env python3
+# Copyright 2023 Amazon.com, Inc. or its affiliates. All Rights Reserved.
+# SPDX-License-Identifier: Apache-2.0
+
+"""
+Run Firecracker in an IPython REPL
+"""
+
+import argparse
+import re
+
+from framework.artifacts import disks, kernels
+from framework.microvm import MicroVMFactory
+from host_tools.cargo_build import get_firecracker_binaries
+
+kernels = list(kernels("vmlinux-*"))
+rootfs = list(disks("ubuntu*ext4"))
+
+
+def parse_byte_size(param):
+    """
+    >>> parse_byte_size("1MB")
+    1048576
+    """
+    unit = {
+        "MB": 2**20,
+        "GB": 2**30,
+    }
+    match = re.match(r"(?P<val>\d+)(?P<unit>[MG]B)", param.upper())
+    return int(match.group("val")) * unit[match.group("unit")]
+
+
+parser = argparse.ArgumentParser()
+parser.add_argument(
+    "--kernel",
+    choices=kernels,
+    default=kernels[-1],
+    help=f"Kernel to use. [{kernels[-1]}]",
+)
+parser.add_argument(
+    "--rootfs",
+    choices=rootfs,
+    default=rootfs[-1],
+    help=f"Rootfs to use. [{rootfs[-1]}]",
+)
+parser.add_argument("--vcpus", type=int, default=2)
+parser.add_argument(
+    "--guest-mem-size",
+    type=parse_byte_size,
+    default=128 * 2**20,  # 128MB
+)
+parser.add_argument("--rootfs-size", type=parse_byte_size, default=1 * 2**30)  # 1GB
+args = parser.parse_args()
+print(args)
+
+
+print("This step may take a while to compile Firecracker ...")
+vmfcty = MicroVMFactory("/srv", None, *get_firecracker_binaries())
+uvm = vmfcty.build(args.kernel, args.rootfs)
+uvm.help.enable_console()
+uvm.help.resize_disk(uvm.rootfs_file, args.rootfs_size)
+uvm.spawn()
+uvm.help.print_log()
+uvm.add_net_iface()
+uvm.basic_config(vcpu_count=args.vcpus, mem_size_mib=args.guest_mem_size // 2**20)
+uvm.start()
+uvm.get_all_metrics()

tools/test.sh

@@ -35,5 +35,6 @@ say "Copy CI artifacts to /srv, so hardlinks work"
 cp -ruvf build/img /srv
 
 cd tests
+export PYTEST_ADDOPTS="${PYTEST_ADDOPTS:-} --pdbcls=IPython.terminal.debugger:TerminalPdb"
 pytest "$@"
 exit $?