src/discover_govpl.py

#!/usr/bin/env python3
"""Discover gov.pl subsites + their news-section paths and write a committed
manifest (govpl_subsites.json) that fetch_govpl.py consumes.

gov.pl offers no sitemap or API for enumeration, and news-section slugs are
non-uniform: ministries use `/aktualnosci`, but voivodeship/agency subsites use
`/wiadomosci2`, `/aktualnosci10`, `/wszystkie-aktualnosci`, etc. (gov.pl appends
numeric suffixes to disambiguate repeated slugs). So discovery is a separate,
auditable step — freeze the JS-rendered subsite list, then probe each landing
page for its deepest-paginating news section. fetch_govpl.py then reads the
manifest with plain stdlib (no browser), keeping the fetch reproducible.

SEED_SLUGS was captured from the rendered catalog at
https://www.gov.pl/web/gov/katalog-jednostek on 2026-07-18 (a client-side list,
NOT fetchable over plain HTTP). To refresh, open that page in a browser console
and run:
    [...new Set([...document.querySelectorAll('a[href*="/web/"]')]
      .map(a => (a.getAttribute('href').match(/\\/web\\/([a-z0-9-]+)/i)||[])[1])
      .filter(Boolean))].filter(s => s !== 'gov')
then paste the array into SEED_SLUGS below.

All gov.pl text is CC-BY-SA 4.0 (site footer), government-authored/hosted.

Usage:
  python3 src/discover_govpl.py --out src/govpl_subsites.json
"""
from __future__ import annotations
import argparse, http.client, json, re, time
from datetime import date
from html import unescape
from urllib.request import urlopen, Request
from urllib.error import URLError, HTTPError

BASE = "https://www.gov.pl"
UA = {"User-Agent": "polish-dynaword/0.1 (+research; openly-licensed corpus)",
      "Accept": "text/html"}

# Frozen JS-rendered catalog (see module docstring for refresh recipe).
SEED_SLUGS = [
    "premier", "aktywa-panstwowe", "cyfryzacja", "edukacja", "energia",
    "finanse", "fundusze-regiony", "infrastruktura", "klimat", "kultura",
    "nauka", "obrona-narodowa", "rodzina", "rolnictwo", "rozwoj-technologia",
    "sport", "sprawiedliwosc", "mswia", "dyplomacja", "zdrowie", "zermswia",
    "arimr", "chemikalia", "rpp", "gdos", "gif", "piorin", "gios", "gis",
    "gitd", "gugik", "krus", "paa", "rcb", "udsc", "prokuratoria", "urpl",
    "uzp", "uw-kujawsko-pomorski", "uw-lubelski", "uw-lubuski", "uw-lodzki",
    "uw-mazowiecki", "uw-opolski", "uw-podkarpacki", "uw-podlaski",
    "uw-warminsko-mazurski", "uw-zachodniopomorski", "gddkia-bialystok",
    "gddkia-bydgoszcz", "gddkia-gdansk", "gddkia-katowice", "gddkia-kielce",
    "gddkia-krakow", "gddkia-lublin", "gddkia-lodz", "gddkia-olsztyn",
    "gddkia-opole", "gddkia-poznan", "gddkia-rzeszow", "gddkia-szczecin",
    "gddkia-warszawa", "gddkia-wroclaw", "gddkia-zielona-gora", "wsse-bialystok",
    "wsse-bydgoszcz", "wsse-gdansk", "wsse-gorzowwlkp", "wsse-katowice",
    "wsse-kielce", "wsse-krakow", "wsse-lublin", "wsse-lodz", "wsse-olsztyn",
    "wsse-opole", "wsse-poznan", "wsse-rzeszow", "wsse-szczecin",
    "wsse-warszawa", "wsse-wroclaw", "prokuratura-krajowa", "po-bialystok",
    "po-bielsko-biala", "po-bydgoszcz", "po-elblag", "po-gdansk", "po-gliwice",
    "po-gorzow-wielkopolski", "po-katowice", "po-kielce", "po-krakow",
    "po-legnica", "po-lublin", "po-lodz", "po-lomza", "po-nowy-sacz",
    "po-olsztyn", "po-opole", "po-ostroleka", "po-ostrow-wielkopolski",
    "po-piotrkow-trybunalski", "po-plock", "po-poznan", "po-rzeszow",
    "po-siedlce", "po-sieradz", "po-slupsk", "po-sosnowiec", "po-swidnica",
    "po-tarnobrzeg", "po-tarnow", "po-torun", "po-warszawa", "po-warszawa-praga",
    "po-wloclawek", "po-wroclaw", "po-zielona-gora", "pr-gdansk", "pr-katowice",
    "pr-krakow", "pr-lublin", "pr-lodz", "pr-poznan", "pr-rzeszow",
    "pr-szczecin", "pr-warszawa", "pr-wroclaw", "kgpsp", "kwpsp-gdansk",
    "kwpsp-opole", "kwpsp-poznan", "cskmswia", "spzoz-mswia-katowice",
    "spzoz-mswia-lublin", "spzoz-mswia-opole", "spzoz-mswia-szczecin",
    "spzoz-mswia-zielona-gora", "spzoz-mswia-glucholazy", "krrit", "kowr",
    "kzn", "nck", "wody-polskie",
]

# A landing-page sub-page counts as a news section if its slug starts with one
# of these (gov.pl appends -suffix / digits, e.g. aktualnosci10, wiadomosci2).
_NEWS_PREFIX = re.compile(r"^(wszystkie-aktualnosci|aktualnosci|wiadomosci|"
                          r"serwis-prasowy|komunikaty)", re.I)
# On a listing page each article preview is an <span class="date"> ... </span>
# (inside a class="event" block) followed by <div class="title"><a href=...>.
# Binding the two in one match keeps date/title/url aligned per article.
_ARTICLE = re.compile(
    r'<span class="date">\s*([\d.]+)\s*</span>.*?'
    r'<div class="title">\s*<a href="([^"]+)"[^>]*>\s*(.*?)\s*</a>',
    re.I | re.S)
_PAGE = re.compile(r'[?&]page=(\d+)')


def http_get_url(url: str, tries: int = 4) -> tuple[str | None, str]:
    """GET, returning (text, final_url_after_redirects). text is None on 404 or
    exhausted retries. Needed because gov.pl news aliases (e.g. /aktualnosci)
    302-redirect to a canonical feed (/wydarzenia) and DROP the ?page= param —
    so pagination must run against the resolved canonical URL, not the alias."""
    for i in range(tries):
        try:
            with urlopen(Request(url, headers=UA), timeout=60) as r:
                return r.read().decode("utf-8", "replace"), r.geturl()
        # OSError covers URLError/TimeoutError/socket/ssl/ConnectionReset;
        # HTTPException covers IncompleteRead (truncated body) — all transient, retry.
        except (HTTPError, OSError, http.client.HTTPException) as e:
            if isinstance(e, HTTPError) and e.code == 404:
                return None, url
            time.sleep(1.5 * (i + 1))
    return None, url


def http_get(url: str, tries: int = 4) -> str | None:
    """GET text, retrying transient errors; None on 404 or exhausted retries."""
    return http_get_url(url, tries)[0]


def listing_articles(html: str, slug: str) -> list[dict]:
    """{url,title,date} for real articles on a listing page of subsite `slug`."""
    out = []
    prefix = f"/web/{slug}/"
    for date_str, href, title in _ARTICLE.findall(html):
        if href.startswith(prefix):
            out.append({
                "url": href,
                "title": unescape(re.sub(r"\s+", " ", title)).strip(),
                "date": date_str,
            })
    return out


def max_page(html: str) -> int:
    nums = [int(n) for n in _PAGE.findall(html)]
    return max(nums) if nums else 1


def news_candidates(landing_html: str, slug: str) -> list[str]:
    """Distinct same-subsite sub-slugs that look like a news section."""
    seen = {}
    for sub in re.findall(rf'href="/web/{re.escape(slug)}/([a-z0-9-]+)"', landing_html):
        if _NEWS_PREFIX.match(sub):
            seen[sub] = True
    return list(seen)


def probe_subsite(slug: str) -> dict | None:
    """Resolve a subsite's best news section -> {slug, news_path, pages} or None."""
    landing = http_get(f"{BASE}/web/{slug}")
    if not landing:
        return None
    best = None
    for sub in news_candidates(landing, slug):
        html = http_get(f"{BASE}/web/{slug}/{sub}")
        if not html:
            continue
        n_art = len(listing_articles(html, slug))
        if n_art == 0:
            continue
        pages = max_page(html)
        # Prefer the deepest-paginating feed; tie-break the shorter (more general) slug.
        key = (pages, -len(sub))
        if best is None or key > best[0]:
            best = (key, sub, pages)
        time.sleep(0.2)
    if best is None:
        return None
    return {"slug": slug, "news_path": best[1], "pages": best[2]}


def main():
    ap = argparse.ArgumentParser()
    ap.add_argument("--out", default="src/govpl_subsites.json")
    ap.add_argument("--slugs", nargs="*", help="override SEED_SLUGS (for testing)")
    args = ap.parse_args()

    slugs = args.slugs or SEED_SLUGS
    manifest, skipped = [], []
    for i, slug in enumerate(slugs, 1):
        rec = probe_subsite(slug)
        if rec:
            manifest.append(rec)
            print(f"[{i}/{len(slugs)}] {slug} -> {rec['news_path']} ({rec['pages']}p)", flush=True)
        else:
            skipped.append(slug)
            print(f"[{i}/{len(slugs)}] {slug} -> NO NEWS SECTION (skipped)", flush=True)

    total_pages = sum(r["pages"] for r in manifest)
    out = {
        "generated": date.today().isoformat(),
        "source": f"{BASE}/web/gov/katalog-jednostek",
        "subsites": manifest,
        "skipped": skipped,  # logged, not silently dropped
        "total_pages": total_pages,
    }
    with open(args.out, "w", encoding="utf-8") as f:
        json.dump(out, f, ensure_ascii=False, indent=2)
    print(f"\nwrote {args.out}: {len(manifest)} subsites, {total_pages} listing pages, "
          f"{len(skipped)} skipped")


if __name__ == "__main__":
    main()