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Snapshots

docs/sdk/python/snapshots.mdx

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Capture the disk state of a stopped sandbox as a reusable artifact, then boot fresh sandboxes from it. Snapshots are disk-only and require a sandbox that is not running. See Snapshots for concepts and walkthroughs.

<div className="msb-glance"> <p className="msb-gl"><span className="msb-dot static"></span>Take a snapshot<span className="msb-ct">3</span></p> <a className="msb-row" href="#handle-snapshot"><span className="msb-rn">handle.snapshot()</span><span className="msb-rg">snapshot under a name</span></a> <a className="msb-row" href="#handle-snapshot_to"><span className="msb-rn">handle.snapshot_to()</span><span className="msb-rg">snapshot to a path</span></a> <a className="msb-row" href="#snapshot-create"><span className="msb-rn">Snapshot.create()</span><span className="msb-rg">snapshot a stopped sandbox by name</span></a> <p className="msb-gl"><span className="msb-dot static"></span>Boot from a snapshot<span className="msb-ct">1</span></p> <a className="msb-row" href="#sandbox-create"><span className="msb-rn">Sandbox.create(snapshot=...)</span><span className="msb-rg">boot a fresh sandbox from an artifact</span></a> <p className="msb-gl"><span className="msb-dot static"></span>Manage artifacts<span className="msb-ct">7</span></p> <a className="msb-row" href="#snapshot-open"><span className="msb-rn">Snapshot.open()</span><span className="msb-rg">open an artifact by name or path</span></a> <a className="msb-row" href="#snapshot-get"><span className="msb-rn">Snapshot.get()</span><span className="msb-rg">handle from the local index</span></a> <a className="msb-row" href="#snapshot-list"><span className="msb-rn">Snapshot.list()</span><span className="msb-rg">indexed snapshots</span></a> <a className="msb-row" href="#snapshot-list_dir"><span className="msb-rn">Snapshot.list_dir()</span><span className="msb-rg">parse a directory of artifacts</span></a> <a className="msb-row" href="#snapshot-remove"><span className="msb-rn">Snapshot.remove()</span><span className="msb-rg">delete an artifact</span></a> <a className="msb-row" href="#snapshot-reindex"><span className="msb-rn">Snapshot.reindex()</span><span className="msb-rg">rebuild the local index</span></a> <a className="msb-row" href="#snapshot-export"><span className="msb-rn">Snapshot.export()</span><span className="msb-rg">bundle into an archive</span></a> <p className="msb-gl"><span className="msb-dot static"></span>Move artifacts<span className="msb-ct">1</span></p> <a className="msb-row" href="#snapshot-import_"><span className="msb-rn">Snapshot.import_()</span><span className="msb-rg">unpack an archive</span></a> <p className="msb-gl"><span className="msb-dot instance"></span>Inspect<span className="msb-ct">3</span></p> <a className="msb-row" href="#snap-verify"><span className="msb-rn">snap.verify()</span><span className="msb-rg">recompute and check integrity</span></a> <a className="msb-row" href="#handle-open"><span className="msb-rn">handle.open()</span><span className="msb-rg">load full metadata from a handle</span></a> <a className="msb-row" href="#handle-remove"><span className="msb-rn">handle.remove()</span><span className="msb-rg">delete via a handle</span></a> <p className="msb-gl"><span className="msb-dot type"></span>Types</p> <div className="msb-chiprow"> <a className="msb-typepill" href="#snapshot">Snapshot</a> <a className="msb-typepill" href="#snapshothandle">SnapshotHandle</a> </div> </div> <p className="msb-label" id="typical-flow">Typical flow</p>
python
from microsandbox import Sandbox, Snapshot

# Run setup work, then stop the sandbox
async with await Sandbox.create("baseline", image="python:3.12") as sb:
    await sb.exec("pip", ["install", "numpy"])
    await sb.stop()

# Capture its disk state under a name
snap = await Snapshot.create("baseline", name="after-pip-install")
print(snap.digest)

# Boot a fresh sandbox from the artifact
sb2 = await Sandbox.create("worker", snapshot="after-pip-install")

Take a snapshot


<span className="msb-recv">handle.</span><span className="msb-hn">snapshot()</span>

<div className="msb-tags"><span className="msb-tag is-instance">SandboxHandle</span><span className="msb-tag is-async">async</span></div>
python
async def snapshot(self, name: str) -> Snapshot

Snapshot this sandbox under a bare name in the default snapshots directory (~/.microsandbox/snapshots/<name>/). The sandbox must be stopped or crashed. For an explicit filesystem destination, see snapshot_to(). Called on a SandboxHandle, obtained from Sandbox.get().

<p className="msb-label">Parameters</p> <div className="msb-params"> <div className="msb-param"> <div className="msb-param-key"><code>name</code><span className="msb-type">str</span></div> <div className="msb-param-desc">Snapshot name; resolved under the default snapshots directory.</div> </div> </div> <p className="msb-label">Returns</p> <div className="msb-params"> <div className="msb-param"> <div className="msb-param-key"><a className="msb-type" href="#snapshot">Snapshot</a></div> <div className="msb-param-desc">The captured snapshot.</div> </div> </div> <Accordion title="Example">
python
handle = await Sandbox.get("baseline")
snap = await handle.snapshot("after-pip-install")
print(snap.digest)
</Accordion>

<span className="msb-recv">handle.</span><span className="msb-hn">snapshot_to()</span>

<div className="msb-tags"><span className="msb-tag is-instance">SandboxHandle</span><span className="msb-tag is-async">async</span></div>
python
async def snapshot_to(self, path: str | os.PathLike) -> Snapshot

Snapshot this sandbox to an explicit filesystem path. The sandbox must be stopped or crashed.

<p className="msb-label">Parameters</p> <div className="msb-params"> <div className="msb-param"> <div className="msb-param-key"><code>path</code><span className="msb-type">str | os.PathLike</span></div> <div className="msb-param-desc">Destination artifact directory.</div> </div> </div> <p className="msb-label">Returns</p> <div className="msb-params"> <div className="msb-param"> <div className="msb-param-key"><a className="msb-type" href="#snapshot">Snapshot</a></div> <div className="msb-param-desc">The captured snapshot.</div> </div> </div> <Accordion title="Example">
python
handle = await Sandbox.get("baseline")
snap = await handle.snapshot_to("/data/snapshots/baseline")
</Accordion>

<span className="msb-recv">Snapshot.</span><span className="msb-hn">create()</span>

<div className="msb-tags"><span className="msb-tag is-static">static</span><span className="msb-tag is-async">async</span></div>
python
@staticmethod
async def create(
    source_sandbox: str,
    *,
    name: str | None = None,
    path: str | os.PathLike | None = None,
    labels: dict[str, str] | None = None,
    force: bool = False,
    record_integrity: bool = False,
) -> Snapshot

Create a snapshot from a stopped or crashed sandbox. Exactly one of name= (resolved under the default snapshots directory) or path= (explicit filesystem destination) is required.

<p className="msb-label">Parameters</p> <div className="msb-params"> <div className="msb-param"> <div className="msb-param-key"><code>source_sandbox</code><span className="msb-type">str</span></div> <div className="msb-param-desc">Name of the stopped or crashed sandbox to capture.</div> </div> <div className="msb-param"> <div className="msb-param-key"><code>name</code><span className="msb-type">str | None</span></div> <div className="msb-param-desc">Snapshot name under the default snapshots directory. Mutually exclusive with <code>path</code>.</div> </div> <div className="msb-param"> <div className="msb-param-key"><code>path</code><span className="msb-type">str | os.PathLike | None</span></div> <div className="msb-param-desc">Explicit destination directory. Mutually exclusive with <code>name</code>.</div> </div> <div className="msb-param"> <div className="msb-param-key"><code>labels</code><span className="msb-type">dict[str, str] | None</span></div> <div className="msb-param-desc">User-supplied labels stored in the manifest.</div> </div> <div className="msb-param"> <div className="msb-param-key"><code>force</code><span className="msb-type">bool</span></div> <div className="msb-param-desc">Overwrite an existing destination. Default <code>False</code>.</div> </div> <div className="msb-param"> <div className="msb-param-key"><code>record_integrity</code><span className="msb-type">bool</span></div> <div className="msb-param-desc">Record an integrity hash in the manifest so the artifact can be verified later. Default <code>False</code>.</div> </div> </div> <p className="msb-label">Returns</p> <div className="msb-params"> <div className="msb-param"> <div className="msb-param-key"><a className="msb-type" href="#snapshot">Snapshot</a></div> <div className="msb-param-desc">The captured snapshot.</div> </div> </div> <Accordion title="Example">
python
snap = await Snapshot.create(
    "baseline",
    name="after-pip-install",
    labels={"stage": "post-deps"},
    record_integrity=True,
)
</Accordion>

Boot from a snapshot


<span className="msb-recv">Sandbox.</span><span className="msb-hn">create()</span>

<div className="msb-tags"><span className="msb-tag is-static">static</span><span className="msb-tag is-async">async</span></div>
python
@staticmethod
async def create(name: str, *, snapshot: str | os.PathLike | None = None, **kwargs) -> Sandbox

Boot a fresh sandbox from a snapshot artifact by passing snapshot= as a peer of image=. The two are mutually exclusive: pass exactly one. See Sandbox.create() for the full set of configuration kwargs.

<p className="msb-label">Parameters</p> <div className="msb-params"> <div className="msb-param"> <div className="msb-param-key"><code>name</code><span className="msb-type">str</span></div> <div className="msb-param-desc">Sandbox name, up to 128 UTF-8 bytes.</div> </div> <div className="msb-param"> <div className="msb-param-key"><code>snapshot</code><span className="msb-type">str | os.PathLike | None</span></div> <div className="msb-param-desc">Snapshot bare name or artifact path to boot from instead of <code>image=</code>.</div> </div> </div> <p className="msb-label">Returns</p> <div className="msb-params"> <div className="msb-param"> <div className="msb-param-key"><a className="msb-type" href="/sdk/python/sandbox#instance-methods">Sandbox</a></div> <div className="msb-param-desc">Running sandbox.</div> </div> </div> <Accordion title="Example">
python
# Boot from a snapshot
sb = await Sandbox.create("worker", snapshot="after-pip-install")

# Or from an image (existing flow, unchanged)
sb = await Sandbox.create("worker", image="python:3.12")
</Accordion>

Manage artifacts


<span className="msb-recv">Snapshot.</span><span className="msb-hn">open()</span>

<div className="msb-tags"><span className="msb-tag is-static">static</span><span className="msb-tag is-async">async</span></div>
python
@staticmethod
async def open(path_or_name: str) -> Snapshot

Open an existing artifact by bare name (resolved under the default snapshots directory) or path. Cheap metadata validation only; does not read the upper file. Use verify() for content checks.

<p className="msb-label">Parameters</p> <div className="msb-params"> <div className="msb-param"> <div className="msb-param-key"><code>path_or_name</code><span className="msb-type">str</span></div> <div className="msb-param-desc">Bare snapshot name or artifact directory path.</div> </div> </div> <p className="msb-label">Returns</p> <div className="msb-params"> <div className="msb-param"> <div className="msb-param-key"><a className="msb-type" href="#snapshot">Snapshot</a></div> <div className="msb-param-desc">The opened snapshot.</div> </div> </div> <Accordion title="Example">
python
snap = await Snapshot.open("after-pip-install")
print(snap.image_ref)
</Accordion>

<span className="msb-recv">Snapshot.</span><span className="msb-hn">get()</span>

<div className="msb-tags"><span className="msb-tag is-static">static</span><span className="msb-tag is-async">async</span></div>
python
@staticmethod
async def get(name_or_digest: str) -> SnapshotHandle

Look up a handle in the local index by name, digest, or path.

<p className="msb-label">Parameters</p> <div className="msb-params"> <div className="msb-param"> <div className="msb-param-key"><code>name_or_digest</code><span className="msb-type">str</span></div> <div className="msb-param-desc">Snapshot name, digest, or path.</div> </div> </div> <p className="msb-label">Returns</p> <div className="msb-params"> <div className="msb-param"> <div className="msb-param-key"><a className="msb-type" href="#snapshothandle">SnapshotHandle</a></div> <div className="msb-param-desc">Lightweight handle backed by an index row.</div> </div> </div> <Accordion title="Example">
python
h = await Snapshot.get("after-pip-install")
print(h.digest)
</Accordion>

<span className="msb-recv">Snapshot.</span><span className="msb-hn">list()</span>

<div className="msb-tags"><span className="msb-tag is-static">static</span><span className="msb-tag is-async">async</span></div>
python
@staticmethod
async def list() -> list[SnapshotHandle]

List indexed snapshots from the local DB cache.

<p className="msb-label">Returns</p> <div className="msb-params"> <div className="msb-param"> <div className="msb-param-key"><a className="msb-type" href="#snapshothandle">list[SnapshotHandle]</a></div> <div className="msb-param-desc">Indexed snapshot handles.</div> </div> </div> <Accordion title="Example">
python
for h in await Snapshot.list():
    print(h.name, h.digest)
</Accordion>

<span className="msb-recv">Snapshot.</span><span className="msb-hn">list_dir()</span>

<div className="msb-tags"><span className="msb-tag is-static">static</span><span className="msb-tag is-async">async</span></div>
python
@staticmethod
async def list_dir(dir: str | os.PathLike) -> list[Snapshot]

Walk a directory and parse each subdirectory's manifest. Does not touch the index, useful for inspecting external snapshot collections (e.g. a mounted volume of artifacts that were never imported). Skips entries that don't look like snapshot artifacts.

<p className="msb-label">Parameters</p> <div className="msb-params"> <div className="msb-param"> <div className="msb-param-key"><code>dir</code><span className="msb-type">str | os.PathLike</span></div> <div className="msb-param-desc">Directory to scan for artifacts.</div> </div> </div> <p className="msb-label">Returns</p> <div className="msb-params"> <div className="msb-param"> <div className="msb-param-key"><a className="msb-type" href="#snapshot">list[Snapshot]</a></div> <div className="msb-param-desc">One snapshot per valid artifact directory.</div> </div> </div> <Accordion title="Example">
python
for snap in await Snapshot.list_dir("/mnt/artifacts"):
    print(snap.path, snap.digest)
</Accordion>

<span className="msb-recv">Snapshot.</span><span className="msb-hn">remove()</span>

<div className="msb-tags"><span className="msb-tag is-static">static</span><span className="msb-tag is-async">async</span></div>
python
@staticmethod
async def remove(path_or_name: str, *, force: bool = False) -> None

Remove a snapshot artifact and its index row. Refuses if the snapshot has indexed children unless force=True.

<p className="msb-label">Parameters</p> <div className="msb-params"> <div className="msb-param"> <div className="msb-param-key"><code>path_or_name</code><span className="msb-type">str</span></div> <div className="msb-param-desc">Bare snapshot name or artifact path.</div> </div> <div className="msb-param"> <div className="msb-param-key"><code>force</code><span className="msb-type">bool</span></div> <div className="msb-param-desc">Remove even if the snapshot has indexed children. Default <code>False</code>.</div> </div> </div> <Accordion title="Example">
python
await Snapshot.remove("after-pip-install", force=True)
</Accordion>

<span className="msb-recv">Snapshot.</span><span className="msb-hn">reindex()</span>

<div className="msb-tags"><span className="msb-tag is-static">static</span><span className="msb-tag is-async">async</span></div>
python
@staticmethod
async def reindex(dir: str | os.PathLike | None = None) -> int

Walk dir (default: configured snapshots dir) and rebuild the local index. Returns the number of artifacts indexed.

<p className="msb-label">Parameters</p> <div className="msb-params"> <div className="msb-param"> <div className="msb-param-key"><code>dir</code><span className="msb-type">str | os.PathLike | None</span></div> <div className="msb-param-desc">Directory to scan. Default: the configured snapshots directory.</div> </div> </div> <p className="msb-label">Returns</p> <div className="msb-params"> <div className="msb-param"> <div className="msb-param-key"><span className="msb-type">int</span></div> <div className="msb-param-desc">Number of artifacts indexed.</div> </div> </div> <Accordion title="Example">
python
count = await Snapshot.reindex()
print(f"indexed {count} snapshots")
</Accordion>

<span className="msb-recv">Snapshot.</span><span className="msb-hn">export()</span>

<div className="msb-tags"><span className="msb-tag is-static">static</span><span className="msb-tag is-async">async</span></div>
python
@staticmethod
async def export(
    name_or_path: str,
    out: str | os.PathLike,
    *,
    with_parents: bool = False,
    with_image: bool = False,
    plain_tar: bool = False,
) -> None

Bundle a snapshot into a .tar.zst archive. The existing snapshot manifest is archived as-is; create the snapshot with recorded integrity when the archive will cross a trust boundary.

<p className="msb-label">Parameters</p> <div className="msb-params"> <div className="msb-param"> <div className="msb-param-key"><code>name_or_path</code><span className="msb-type">str</span></div> <div className="msb-param-desc">Snapshot bare name or artifact path to export.</div> </div> <div className="msb-param"> <div className="msb-param-key"><code>out</code><span className="msb-type">str | os.PathLike</span></div> <div className="msb-param-desc">Output archive path.</div> </div> <div className="msb-param"> <div className="msb-param-key"><code>with_parents</code><span className="msb-type">bool</span></div> <div className="msb-param-desc">Include the snapshot's parent chain. Default <code>False</code>.</div> </div> <div className="msb-param"> <div className="msb-param-key"><code>with_image</code><span className="msb-type">bool</span></div> <div className="msb-param-desc">Include the pinned base image. Default <code>False</code>.</div> </div> <div className="msb-param"> <div className="msb-param-key"><code>plain_tar</code><span className="msb-type">bool</span></div> <div className="msb-param-desc">Write an uncompressed <code>.tar</code> instead of <code>.tar.zst</code>. Default <code>False</code>.</div> </div> </div> <Accordion title="Example">
python
await Snapshot.export(
    "after-pip-install",
    "/tmp/after-pip-install.tar.zst",
    with_parents=True,
)
</Accordion>

Move artifacts


<span className="msb-recv">Snapshot.</span><span className="msb-hn">import_()</span>

<div className="msb-tags"><span className="msb-tag is-static">static</span><span className="msb-tag is-async">async</span></div>
python
@staticmethod
async def import_(
    archive: str | os.PathLike,
    *,
    dest: str | os.PathLike | None = None,
) -> SnapshotHandle

Unpack a snapshot archive (.tar.zst or .tar) into the snapshots directory, verifying recorded integrity when present. Compression is detected from magic bytes. The trailing underscore is intentional: import is a reserved Python keyword.

<p className="msb-label">Parameters</p> <div className="msb-params"> <div className="msb-param"> <div className="msb-param-key"><code>archive</code><span className="msb-type">str | os.PathLike</span></div> <div className="msb-param-desc">Archive path (<code>.tar.zst</code> or <code>.tar</code>).</div> </div> <div className="msb-param"> <div className="msb-param-key"><code>dest</code><span className="msb-type">str | os.PathLike | None</span></div> <div className="msb-param-desc">Destination directory. Default: the configured snapshots directory.</div> </div> </div> <p className="msb-label">Returns</p> <div className="msb-params"> <div className="msb-param"> <div className="msb-param-key"><a className="msb-type" href="#snapshothandle">SnapshotHandle</a></div> <div className="msb-param-desc">Handle to the imported snapshot.</div> </div> </div> <Accordion title="Example">
python
h = await Snapshot.import_("/tmp/after-pip-install.tar.zst")
print(h.path)
</Accordion>

Inspect


<span className="msb-recv">snap.</span><span className="msb-hn">verify()</span>

<div className="msb-tags"><span className="msb-tag is-instance">Snapshot</span><span className="msb-tag is-async">async</span></div>
python
async def verify(self) -> dict[str, Any]

Recompute the upper layer's content hash and compare against the manifest. Walks data extents only, so a 4 GiB sparse file with a few MB of data verifies in milliseconds.

<p className="msb-label">Returns</p> <div className="msb-params"> <div className="msb-param"> <div className="msb-param-key"><span className="msb-type">dict[str, Any]</span></div> <div className="msb-param-desc">Verification report. The <code>upper.kind</code> field is <code>"not_recorded"</code> when no integrity hash was stored, or <code>"verified"</code> with the recomputed digest.</div> </div> </div> <Accordion title="Example">
python
report = await snap.verify()
if report["upper"]["kind"] == "verified":
    print(f"hash matches: {report['upper']['digest']}")
else:
    print("no integrity hash recorded")
</Accordion>

The report shape:

python
{
    "digest": "sha256:...",
    "path": "/path/to/artifact",
    "upper": {"kind": "not_recorded"}                            # no integrity recorded
        | {"kind": "verified", "algorithm": "...", "digest": "sha256:..."},
}

<span className="msb-recv">handle.</span><span className="msb-hn">open()</span>

<div className="msb-tags"><span className="msb-tag is-instance">SnapshotHandle</span><span className="msb-tag is-async">async</span></div>
python
async def open(self) -> Snapshot

Load the full Snapshot metadata for this handle. Metadata-validated only; does not read the upper file.

<p className="msb-label">Returns</p> <div className="msb-params"> <div className="msb-param"> <div className="msb-param-key"><a className="msb-type" href="#snapshot">Snapshot</a></div> <div className="msb-param-desc">The opened snapshot.</div> </div> </div> <Accordion title="Example">
python
h = await Snapshot.get("after-pip-install")
snap = await h.open()
print(snap.fstype)
</Accordion>

<span className="msb-recv">handle.</span><span className="msb-hn">remove()</span>

<div className="msb-tags"><span className="msb-tag is-instance">SnapshotHandle</span><span className="msb-tag is-async">async</span></div>
python
async def remove(self, *, force: bool = False) -> None

Remove this snapshot artifact and its index row. Refuses if the snapshot has indexed children unless force=True.

<p className="msb-label">Parameters</p> <div className="msb-params"> <div className="msb-param"> <div className="msb-param-key"><code>force</code><span className="msb-type">bool</span></div> <div className="msb-param-desc">Remove even if the snapshot has indexed children. Default <code>False</code>.</div> </div> </div> <Accordion title="Example">
python
h = await Snapshot.get("after-pip-install")
await h.remove(force=False)
</Accordion>

Types

Snapshot

<div className="msb-tags"><span className="msb-tag is-type">class</span></div> <p className="msb-backref">Returned by <a href="#handle-snapshot">snapshot()</a> · <a href="#handle-snapshot_to">snapshot_to()</a> · <a href="#snapshot-create">Snapshot.create()</a> · <a href="#snapshot-open">Snapshot.open()</a> · <a href="#snapshot-list_dir">Snapshot.list_dir()</a> · <a href="#handle-open">handle.open()</a></p>

A fully-parsed snapshot artifact. Properties are read-only attributes (not async).

Property / MethodTypeDescription
pathstrPath to the artifact directory
digeststrCanonical content digest (sha256:hex). The snapshot's identity
size_bytesintApparent size of the captured upper layer in bytes (sparse on disk)
image_refstrImage reference the snapshot was taken from
image_manifest_digeststrOCI manifest digest of the pinned image
formatstr"raw" or "qcow2" (always "raw" today)
fstypestrFilesystem type inside the upper (e.g. "ext4")
parentstr | NoneParent snapshot's digest, or None for a root
created_atstrRFC 3339 timestamp
labelsdict[str, str]User-supplied labels
source_sandboxstr | NoneBest-effort source-sandbox name
verify()Awaitable[dict[str, Any]]Recompute and check the upper-layer integrity hash. See verify()

SnapshotHandle

<div className="msb-tags"><span className="msb-tag is-type">class</span></div> <p className="msb-backref">Returned by <a href="#snapshot-get">Snapshot.get()</a> · <a href="#snapshot-list">Snapshot.list()</a> · <a href="#snapshot-import_">Snapshot.import_()</a></p>

Lightweight handle backed by an index row. Properties are read-only attributes (not async).

Property / MethodTypeDescription
digeststrManifest digest, canonical identity
namestr | NoneConvenience alias
parent_digeststr | NoneParent snapshot digest, or None for a root
image_refstrImage the snapshot was taken from
formatstr"raw" or "qcow2"
size_bytesint | NoneApparent upper size at index time
created_atfloatms since Unix epoch
pathstrLocal artifact directory path
open()Awaitable[Snapshot]Load full metadata. See open()
remove(force=False)Awaitable[None]Delete the artifact and its index row. See remove()