feat(extract): add skip_if_current() and write_jsonl_atomic() helpers

Task 5/6: Compress repeated patterns in extractors:
- skip_if_current(): cursor check + early-return dict (3 extractors)
- write_jsonl_atomic(): working-file → JSONL → compress (2 extractors)
Applied in gisco, geonames, census_usa, playtomic_tenants.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

extract/padelnomics_extract/src/padelnomics_extract/census_usa.py

@@ -19,7 +19,7 @@ from pathlib import Path
 import niquests
 
 from ._shared import HTTP_TIMEOUT_SECONDS, run_extractor, setup_logging
-from .utils import get_last_cursor, landing_path, write_gzip_atomic
+from .utils import landing_path, skip_if_current, write_gzip_atomic
 
 logger = setup_logging("padelnomics.extract.census_usa")
 
@@ -73,10 +73,10 @@ def extract(
         return {"files_written": 0, "files_skipped": 1, "bytes_written": 0}
 
     # Skip if we already have data for this month (annual data, monthly cursor)
-    last_cursor = get_last_cursor(conn, EXTRACTOR_NAME)
+    skip = skip_if_current(conn, EXTRACTOR_NAME, year_month)
-    if last_cursor == year_month:
+    if skip:
         logger.info("already have data for %s — skipping", year_month)
-        return {"files_written": 0, "files_skipped": 1, "bytes_written": 0}
+        return skip
 
     year, month = year_month.split("/")
     url = f"{ACS_URL}&key={api_key}"

extract/padelnomics_extract/src/padelnomics_extract/geonames.py

@@ -19,7 +19,6 @@ Output:  one JSON object per line, e.g.:
 
 import gzip
 import io
-import json
 import os
 import sqlite3
 import zipfile
@@ -28,7 +27,7 @@ from pathlib import Path
 import niquests
 
 from ._shared import HTTP_TIMEOUT_SECONDS, run_extractor, setup_logging
-from .utils import compress_jsonl_atomic, get_last_cursor, landing_path
+from .utils import landing_path, skip_if_current, write_jsonl_atomic
 
 logger = setup_logging("padelnomics.extract.geonames")
 
@@ -139,10 +138,10 @@ def extract(
             tmp.rename(dest)
         return {"files_written": 0, "files_skipped": 1, "bytes_written": 0}
 
-    last_cursor = get_last_cursor(conn, EXTRACTOR_NAME)
+    skip = skip_if_current(conn, EXTRACTOR_NAME, year_month)
-    if last_cursor == year_month:
+    if skip:
         logger.info("already have data for %s — skipping", year_month)
-        return {"files_written": 0, "files_skipped": 1, "bytes_written": 0}
+        return skip
 
     year, month = year_month.split("/")
 
@@ -168,11 +167,7 @@ def extract(
 
     dest_dir = landing_path(landing_dir, "geonames", year, month)
     dest = dest_dir / "cities_global.jsonl.gz"
-    working_path = dest.with_suffix(".working.jsonl")
+    bytes_written = write_jsonl_atomic(dest, rows)
-    with open(working_path, "w") as f:
-        for row in rows:
-            f.write(json.dumps(row, separators=(",", ":")) + "\n")
-    bytes_written = compress_jsonl_atomic(working_path, dest)
     logger.info("written %s bytes compressed", f"{bytes_written:,}")
 
     return {

extract/padelnomics_extract/src/padelnomics_extract/gisco.py

@@ -17,7 +17,7 @@ from pathlib import Path
 import niquests
 
 from ._shared import HTTP_TIMEOUT_SECONDS, run_extractor, setup_logging
-from .utils import get_last_cursor
+from .utils import skip_if_current
 
 logger = setup_logging("padelnomics.extract.gisco")
 
@@ -45,10 +45,10 @@ def extract(
     session: niquests.Session,
 ) -> dict:
     """Download NUTS-2 GeoJSON. Skips if already run this month or file exists."""
-    last_cursor = get_last_cursor(conn, EXTRACTOR_NAME)
+    skip = skip_if_current(conn, EXTRACTOR_NAME, year_month)
-    if last_cursor == year_month:
+    if skip:
         logger.info("already ran for %s — skipping", year_month)
-        return {"files_written": 0, "files_skipped": 1, "bytes_written": 0}
+        return skip
 
     dest = landing_dir / DEST_REL
     if dest.exists():

extract/padelnomics_extract/src/padelnomics_extract/playtomic_tenants.py

@@ -21,7 +21,6 @@ Rate: 1 req / 2 s per IP (see docs/data-sources-inventory.md §1.2).
 Landing: {LANDING_DIR}/playtomic/{year}/{month}/tenants.jsonl.gz
 """
 
-import json
 import os
 import sqlite3
 import time
@@ -33,7 +32,7 @@ import niquests
 
 from ._shared import HTTP_TIMEOUT_SECONDS, run_extractor, setup_logging, ua_for_proxy
 from .proxy import load_proxy_tiers, make_tiered_cycler
-from .utils import compress_jsonl_atomic, landing_path
+from .utils import landing_path, write_jsonl_atomic
 
 logger = setup_logging("padelnomics.extract.playtomic_tenants")
 
@@ -215,11 +214,7 @@ def extract(
             time.sleep(THROTTLE_SECONDS)
 
     # Write each tenant as a JSONL line, then compress atomically
-    working_path = dest.with_suffix(".working.jsonl")
+    bytes_written = write_jsonl_atomic(dest, all_tenants)
-    with open(working_path, "w") as f:
-        for tenant in all_tenants:
-            f.write(json.dumps(tenant, separators=(",", ":")) + "\n")
-    bytes_written = compress_jsonl_atomic(working_path, dest)
     logger.info("%d unique venues -> %s", len(all_tenants), dest)
 
     return {

extract/padelnomics_extract/src/padelnomics_extract/utils.py

@@ -101,6 +101,19 @@ def get_last_cursor(conn: sqlite3.Connection, extractor: str) -> str | None:
     return row["cursor_value"] if row else None
 
 
+_SKIP_RESULT = {"files_written": 0, "files_skipped": 1, "bytes_written": 0}
+
+
+def skip_if_current(conn: sqlite3.Connection, extractor: str, year_month: str) -> dict | None:
+    """Return an early-exit result dict if this extractor already ran for year_month.
+
+    Returns None when the extractor should proceed with extraction.
+    """
+    if get_last_cursor(conn, extractor) == year_month:
+        return _SKIP_RESULT
+    return None
+
+
 # ---------------------------------------------------------------------------
 # File I/O helpers
 # ---------------------------------------------------------------------------
@@ -176,6 +189,20 @@ def write_gzip_atomic(path: Path, data: bytes) -> int:
     return len(compressed)
 
 
+def write_jsonl_atomic(dest: Path, items: list[dict]) -> int:
+    """Write items as JSONL, then compress atomically to dest (.jsonl.gz).
+
+    Compresses the working-file → JSONL → gzip pattern into one call.
+    Returns compressed bytes written.
+    """
+    assert items, "items must not be empty"
+    working_path = dest.with_suffix(".working.jsonl")
+    with open(working_path, "w") as f:
+        for item in items:
+            f.write(json.dumps(item, separators=(",", ":")) + "\n")
+    return compress_jsonl_atomic(working_path, dest)
+
+
 def compress_jsonl_atomic(jsonl_path: Path, dest_path: Path) -> int:
     """Compress a JSONL working file to .jsonl.gz atomically, then delete the source.