Fix non-deterministic empty flight fields via aria-label fallback

fast_flights/core.py

@@ -15,6 +15,80 @@
 
 DataSource = Literal['html', 'js']
 
+
+def _parse_aria_label(label: str) -> dict:
+    """Parse flight details from aria-label as fallback when CSS selectors fail.
+
+    Google Flights always includes a structured aria-label on each flight item,
+    e.g.: 'From 2359 US dollars. Nonstop flight with Alaska. Leaves San Jose
+    Mineta International Airport at 2:25 PM on Sunday, February 15 and arrives
+    at Kona International Airport at 6:13 PM on Sunday, February 15. Total
+    duration 5 hr 48 min.'
+
+    This is used as a fallback when the CSS class names in the HTML differ from
+    what the parser expects (Google obfuscates class names differently depending
+    on the browser fingerprint / TLS fingerprint used by the HTTP client).
+    """
+    result = {}
+
+    # Airline name: "flight with <airline>. Leaves"
+    m = re.search(r'flight with (.+?)\.\s*Leaves', label)
+    result['name'] = m.group(1) if m else ""
+
+    # Departure time: "Leaves <airport> at <time> on <day> and arrives"
+    # Use greedy .+ to skip past airport names that may contain "at"
+    # Use \s* for the space before AM/PM to handle U+202F (narrow no-break space)
+    m = re.search(r'Leaves .+ at (\d+:\d+\s*(?:AM|PM)) on (.+?) and arrives', label)
+    if m:
+        time_str, date_str = m.group(1), m.group(2)
+        time_str = re.sub(r'\s+', ' ', time_str)
+        result['departure'] = f"{time_str} on {_shorten_date(date_str)}"
+    else:
+        result['departure'] = ""
+
+    # Arrival time: "arrives at <airport> at <time> on <day>. Total"
+    m = re.search(r'arrives .+ at (\d+:\d+\s*(?:AM|PM)) on (.+?)\.\s*Total', label)
+    if m:
+        time_str, date_str = m.group(1), m.group(2)
+        time_str = re.sub(r'\s+', ' ', time_str)
+        result['arrival'] = f"{time_str} on {_shorten_date(date_str)}"
+    else:
+        result['arrival'] = ""
+
+    # Duration: "Total duration <dur>."
+    m = re.search(r'Total duration (.+?)\.', label)
+    result['duration'] = m.group(1) if m else ""
+
+    # Stops: "Nonstop" or "1 stop" or "2 stops"
+    m = re.search(r'(Nonstop|\d+ stops?)\s+flight', label)
+    if m:
+        stops_text = m.group(1)
+        result['stops'] = 0 if stops_text == "Nonstop" else int(stops_text.split()[0])
+    else:
+        result['stops'] = "Unknown"
+
+    return result
+
+
+_DAY_ABBREVS = {
+    'Monday': 'Mon', 'Tuesday': 'Tue', 'Wednesday': 'Wed',
+    'Thursday': 'Thu', 'Friday': 'Fri', 'Saturday': 'Sat', 'Sunday': 'Sun',
+}
+_MONTH_ABBREVS = {
+    'January': 'Jan', 'February': 'Feb', 'March': 'Mar', 'April': 'Apr',
+    'May': 'May', 'June': 'Jun', 'July': 'Jul', 'August': 'Aug',
+    'September': 'Sep', 'October': 'Oct', 'November': 'Nov', 'December': 'Dec',
+}
+
+
+def _shorten_date(date_str: str) -> str:
+    """Convert 'Sunday, February 15' to 'Sun, Feb 15'."""
+    for full, abbr in _DAY_ABBREVS.items():
+        date_str = date_str.replace(full, abbr)
+    for full, abbr in _MONTH_ABBREVS.items():
+        date_str = date_str.replace(full, abbr)
+    return date_str
+
 # Default cookies embedded into the app to help bypass common consent gating.
 # These are used only if the caller does not supply cookies (binary) and
 # does not provide cookies via request_kwargs.
@@ -275,6 +349,30 @@ def safe(n: Optional[LexborNode]):
             except ValueError:
                 stops_fmt = "Unknown"
 
+            # Fallback: if CSS selectors missed any key fields, parse from
+            # aria-label. Google serves different obfuscated class names
+            # depending on the browser/TLS fingerprint, but aria-label always
+            # contains structured flight data regardless.
+            if not name or not departure_time or not arrival_time or not duration or stops_fmt == "Unknown":
+                # Check the item element itself first, then descendants
+                aria = item.attributes.get("aria-label", "") or ""
+                if not aria or "flight" not in aria:
+                    aria_el = item.css_first("[aria-label*='flight']")
+                    if aria_el:
+                        aria = aria_el.attributes.get("aria-label", "") or ""
+                if aria and "flight" in aria:
+                    parsed = _parse_aria_label(aria)
+                    if not name:
+                        name = parsed.get('name', '')
+                    if not departure_time:
+                        departure_time = parsed.get('departure', '')
+                    if not arrival_time:
+                        arrival_time = parsed.get('arrival', '')
+                    if not duration:
+                        duration = parsed.get('duration', '')
+                    if stops_fmt == "Unknown":
+                        stops_fmt = parsed.get('stops', 'Unknown')
+
             flights.append(
                 {
                     "is_best": is_best_flight,