Overview
dsh-attachment-local
Source-level overviewThe private local implementation of @deepseek-ai/dsh-attachment. Objects land at <DSH_HOME>/attachments/v1/objects/<sha256-prefix>/<sha256> and are addressed by an opaque sha256: id. Each process proves a home durable once by syncing every ancestor entry to the filesystem root, so a directory another process created but has not yet synced is never mistaken for a safe boundary. Writes then use a private staging directory, owner-only files, a synced temporary file, an atomic exclusive hard-link publish, and directory syncs on the publication path (POSIX; Windows relies on filesystem metadata journaling) so the reported reference survives a crash. Write admission and reads fully decode the raster before accepting its format and dimensions; reads also re-check the digest and logged metadata. Byte and pixel limits are write-time admission policy, so a later policy reduction does not make already-admitted history unreadable.Collapse technical overview
@deepseek-ai/dsh-attachment. Objects land at <DSH_HOME>/attachments/v1/objects/<sha256-prefix>/<sha256> and are addressed by an opaque sha256: id. Each process proves a home durable once by syncing every ancestor entry to the filesystem root, so a directory another process created but has not yet synced is never mistaken for a safe boundary. Writes then use a private staging directory, owner-only files, a synced temporary file, an atomic exclusive hard-link publish, and directory syncs on the publication path (POSIX; Windows relies on filesystem metadata journaling) so the reported reference survives a crash. Write admission and reads fully decode the raster before accepting its format and dimensions; reads also re-check the digest and logged metadata. Byte and pixel limits are write-time admission policy, so a later policy reduction does not make already-admitted history unreadable.This is an atomic module already shipped with Harness, not a standalone profile layer.
Capabilities
What it contributes
README / EN
Package documentation
@deepseek-ai/dsh-attachment-local
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The private local implementation of @deepseek-ai/dsh-attachment. Objects land at <DSH_HOME>/attachments/v1/objects/<sha256-prefix>/<sha256> and are addressed by an opaque sha256: id. Each process proves a home durable once by syncing every ancestor entry to the filesystem root, so a directory another process created but has not yet synced is never mistaken for a safe boundary. Writes then use a private staging directory, owner-only files, a synced temporary file, an atomic exclusive hard-link publish, and directory syncs on the publication path (POSIX; Windows relies on filesystem metadata journaling) so the reported reference survives a crash. Write admission and reads fully decode the raster before accepting its format and dimensions; reads also re-check the digest and logged metadata. Byte and pixel limits are write-time admission policy, so a later policy reduction does not make already-admitted history unreadable.
DSH_HOME resolves through the shared path policy: explicit config, $DSH_HOME, then ~/.dsh. Session logs contain only the reference and verified metadata, never this host path. readImage forwards optional cancellation into the filesystem read, observes it around verification, and preserves it instead of wrapping it as ATTACHMENT_READ_FAILED.
Model Experience
Indirectly, through durable replay of historical user images and structured model image output after restart and fork.
KV Cache effect
None beyond the image block owned by the requesting adapter.
Known Limitations and Deferred Work
- Objects are retained indefinitely; reference-aware garbage collection is deferred.
- The local backend assumes the host and provider adapter share this filesystem service.
- Animated GIF metadata is validated from the logical screen; frame-level decoding policy is provider-owned.
LIMITATIONS
Known limitations
- Objects are retained indefinitely; reference-aware garbage collection is deferred. - The local backend assumes the host and provider adapter share this filesystem service. - Animated GIF metadata is validated from the logical screen; frame-level decoding policy is provider-owned.