#rlsbl.commands.check

#rlsbl.commands.check

Check command to query package name availability across npm, PyPI, Go module proxy (pkg.go.dev), and GitHub repository namespaces.

#_request_with_backoff

def _request_with_backoff(url, timeout=5, max_retries=3)

Wrap urllib.request.urlopen with retry logic for HTTP 429 responses.

On HTTP 429 (Too Many Requests): reads the Retry-After header (seconds). If present, sleeps that long. If absent, uses exponential backoff starting at 2 seconds (2, 4, 8, ...).

On other HTTP errors or non-HTTP errors (URLError, timeout): raises immediately without retrying.

Returns the response object on success, or raises the last exception after exhausting retries.

#_ultranormalize

def _ultranormalize(name)

Ultranormalize a package name for typosquatting detection.

Strips all separators (-, _, .), replaces visually ambiguous characters (l, L, i, I -> 1; o, O -> 0), and lowercases the result.

#_generate_ultranorm_variants

def _generate_ultranorm_variants(name)

Generate name variants that share the same ultranormalized form.

Starting from the PEP 503 normalized form (lowercase, separators normalized), produces all combinations of ambiguous character substitutions: l <-> 1, o <-> 0, i <-> 1 Returns up to 64 variants, excluding the original name itself.

#_normalize_npm_moniker

def _normalize_npm_moniker(name)

Normalize an npm package name using npm's moniker collision algorithm.

Strips all '-', '.', '_' characters and lowercases the result. Two packages whose monikers match are considered conflicting by npm.

#_search_npm_similar

def _search_npm_similar(name)

Search the npm registry for packages with conflicting monikers.

Queries the npm search API for packages similar to name, then compares each result's normalized moniker against the candidate's. Returns a list of original package names that conflict.

On any failure (network, JSON parse), returns an empty list for graceful degradation.

#check_npm_availability

def check_npm_availability(name)

Check if an npm package name is available.

Returns {"status": "available"|"taken"|"error", "message"?: str}. Distinguishes 404 (truly available) from network/other errors.

#get_npm_variants

def get_npm_variants(name)

Generate common npm name variants for similarity checking.

#check_pypi_availability

def check_pypi_availability(name)

Check if a PyPI package name is available.

Uses the Simple API (PEP 503) which correctly returns 200 for registered packages even if they have no releases (unlike the JSON API which 404s).

Returns {"status": "available"|"taken"|"error", "message"?: str}. Distinguishes 404 (truly available) from network/other errors.

#get_pypi_variants

def get_pypi_variants(name)

Generate common PyPI name variants for similarity checking.

#check_go_availability

def check_go_availability(name)

Check if a Go module path exists on pkg.go.dev.

Returns {"status": "not_found"|"exists"|"error", "message"?: str, "note"?: str}.

Go modules use repository paths (e.g. github.com/user/repo), not a flat claimable namespace, so we report "not found" / "exists" rather than the "available" / "taken" language used for npm and PyPI.

#check_github_availability

def check_github_availability(name)

Check if a repository name exists on GitHub.

Searches the GitHub API for repositories with the given name. Returns {"status": "available"|"exists"|"error", "count": int, ...}.

#_check_variants

def _check_variants(name, check_fn, get_variants_fn)

Check name variants for similarity using the given availability checker.

Returns a list of variant names that are taken/exist.

#_check_stdlib_collision

def _check_stdlib_collision(name)

Check if a name collides with a Python standard library module.

PEP 503 normalizes both the candidate and each stdlib name, then compares. Returns the stdlib module name on collision, or None.

#_check_single_name

def _check_single_name(name, registry)

Check a single name on a given registry, returning a structured result.

Returns a dict with keys: - name: the package name checked - registry: which registry was checked - status: "available", "taken", "exists", "not_found", or "error" - variants: list of similar names that are taken (npm/pypi only) - github_count: number of GitHub repos with this name (or None on error) - reason: why the name is taken/unavailable, or None if available/error. Values: "registered", "stdlib", "moniker", "ultranorm" (set by _apply_ultranorm_check), or None. - error: error message if status is "error" (absent otherwise) - note: informational note (go only, absent otherwise)

#_format_single_result

def _format_single_result(result)

Print the verbose output for a single name check result.

Reproduces the original detailed output format with variant warnings and GitHub info.

#_format_table_row

def _format_table_row(result)

Return a compact one-line dict suitable for table rendering.

Keys: name, status. The status is a short human-readable string.

#_apply_ultranorm_check

def _apply_ultranorm_check(result, registry, ultranorm_flag, delay_ms)

Apply ultranormalization variant checking to a result dict (in-place).

Only runs for PyPI when the --ultranormalized-variants flag is set and the name was initially available. Checks each generated variant against PyPI Simple API, applying a delay between requests. Sets ultranorm_conflicts (list of taken variant names) and ultranorm_caveat (always True when the flag is used) on the result.

#run_cmd

def run_cmd(registry, args, flags)

Check command handler.

Checks package name availability on npm, PyPI, or Go, and warns about similar names. Accepts one or more package names as positional arguments.