deepseek-harness/packages/util/home-paths/README.md

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description: "Shared resolution of the DeepSeek Harness home and user-data paths for packages that need one consistent root, tilde expansion, and stable watch paths."

kind: "package-library"

@deepseek-ai/dsh-home-paths

English | 中文

Summary

@deepseek-ai/dsh-home-paths lets package authors resolve one DeepSeek Harness data root and derive child paths from it. An explicit path wins over $DSH_HOME, which wins over ~/.dsh; blank environment values are ignored. Its public helpers can render the root without revealing an absolute machine path, expand only bare or current-user tilde forms, and canonicalize watch targets whose final components do not yet exist. Use it as a direct library dependency, not through cordis.yml.

Table of Contents

• Use this package
• Understand the implementation
• Further Exploration
• Known Limitations and Deferred Work
• Dev Note

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Use this package

Use these helpers wherever a package must agree with the rest of the harness about where user data lives: resolve the home once, then derive every child path from it.

Resolving the home

import { resolveDshHome, dshHomePath, dshCachePath } from '@deepseek-ai/dsh-home-paths'

const home = resolveDshHome()                // configured path, else $DSH_HOME, else ~/.dsh
const settings = dshHomePath('settings')     // join one child onto the resolved home
const cache = dshCachePath('models')         // $DSH_HOME/cache/models, default ~/.dsh/cache/models

An explicit configured path has the highest precedence, then $DSH_HOME, then the default ~/.dsh. An empty or whitespace-only $DSH_HOME is treated as unset, so a blank override never resolves the home to the current working directory.

dshCachePath(...segments) derives paths from the resolved home's cache directory. With no segments it returns the cache directory itself. Pass an initial options object, dshCachePath({ dshHome: home }, ...segments), to use an explicit configured home with the same precedence and tilde expansion. It returns an absolute path without creating directories.

Displaying a home

For user-facing paths, render the root symbolically rather than as a machine path: the default home displays as ~/.dsh and any configured home displays as $DSH_HOME. The display form never leaks an absolute machine path.

Expanding user paths

expandHomePath expands a leading ~, ~/, or ~\ against the operating-system home and leaves everything else untouched — non-tilde paths and named-user forms such as ~alice/... pass through unchanged.

Canonicalizing watch paths

canonicalizeWatchPath gives a native filesystem watcher one canonical spelling of its target: the deepest existing ancestor is resolved through realpath and any missing suffix is restored, so a file or directory can be watched before it is created. This prevents Windows from treating a regular-file ancestor as ordinary absence, and prevents 8.3 short-name aliases from mixing with the long paths the native watcher backend emits.

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Understand the implementation

Implementation internals — click to expand

The package is built on one principle: all harness user data lives under one root, and every other helper derives from that decision. ### Source map | File | Role | |---|---| | [`src/index.ts`](src/index.ts) | Home resolution, path joining, display, tilde expansion, and watch-path canonicalization | | — | No runtime invariant companion is published; this pure utility owns no event stream or mutable runtime data; its resolution rules and value algebra are enforced by unit tests. | ### Resolution rules `resolveDshHome` reads the explicit override, then `$DSH_HOME`, then falls back to the operating-system home joined with `.dsh`. The chosen value is tilde-expanded and normalized to an absolute path; `dshHomePath` joins child segments with Node's platform path rules. `dshHomeDisplay` compares the resolved path against the default root and returns the symbolic label, so a configured home never leaks its absolute path. ### Canonicalization mechanics `canonicalizeWatchPath` walks up from the target until it finds an existing ancestor, resolves it with `realpath`, proves it is an enumerable directory, and restores the missing suffix. Errors other than absence propagate, and a missing-suffix ancestor that is not a directory is rejected.

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Further Exploration

Read these pages when you need the launcher or the consumers that depend on a single home root.

• Boot package — the launcher that resolves the home before any plugin mounts.
• Shell environment — how DSH_HOME reaches model shell calls.
• Anonymous user id — a stored identity file under the resolved home.

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Known Limitations and Deferred Work

These limits define when the helpers are not the right tool. They are current package constraints, not a task backlog.

• Expansion is deliberately narrow — only bare ~, ~/..., and ~\... use the current operating-system home; named-user forms such as ~alice/..., environment variables, and shell expressions remain unchanged.
• Canonicalization reads but never mutates — canonicalizeWatchPath performs realpath probes and propagates errors other than absence; callers still own directory creation, permissions, and trust policy for the resulting path.

Dev Note

Working context for maintainers — click to expand

None.