Hwaro::Services::DevPath

Percent-encoded NUL. Deleting it (what the shared sanitize_path does) made /index%00.html serve the real homepage with a 200, while the StaticFileHandler sitting in the same chain answers a decoded NUL with 400 — an inconsistency inside one server. Fail closed instead.

%2f / %5c in any casing. Double-encoded forms (%252f) survive the single decode as a literal %2f inside one segment, which then simply doesn't exist on disk — no separate rule needed.

The canonical form of path when it is not already canonical, or nil when nothing should be redirected.

Mirrors HTTP::StaticFileHandler's own test exactly — decode once, Path.posix(...).expand("/"), compare as Path — so a pre-empt built on this fires when and only when stdlib would have redirected, and lands on the same target (Path#expand keeps a trailing slash, so a directory URL stays a directory URL). The result is re-encoded because the comparison runs on decoded bytes.

Handlers pre-empt stdlib rather than letting it answer because a redirect it emits reflects whatever the chain did to request.path along the way — IndexRewriteHandler's / → /index.html rewrite leaked into it — and because Response#redirect closes the response, so no handler above can correct the Location afterwards.

A segment that is nothing but dots and spaces. .. is the parent link; ..., ".. " and ". " are included because Windows strips BOTH trailing dots and trailing spaces from a path component, which can collapse them onto one that traverses. Same predicate the shared PathUtils.sanitize_path uses, so the two cannot drift.

Deliberately NOT "contains ..": after a single decode only such a segment can traverse, while lib.v1..2.js or a slug like a..b are ordinary filenames that a static host serves. Rejecting those would reintroduce — in the opposite direction — the dev/prod divergence this resolver exists to remove.

Percent-encode a resolved relative path back into a URI reference. safe_relative hands back decoded bytes, so a redirect built straight from it would put a raw space (or raw UTF-8) into Location:.

Resolve a request path to a path relative to the output root, or nil when the request must not be served from disk at all. An empty string means "the output root itself" (e.g. /), which callers handle separately from nil. True for request shapes no static host serves: a backslash separator, an encoded / or \, or a NUL in any form. Declining them in our own handlers is not enough — HTTP::StaticFileHandler decodes once too and would happily resolve /%2Fguide%2Findex.html to the real page — so UnservablePathHandler turns this predicate into an actual 404 before the request can reach it.