Add constants module and use for db path

scripts/bitcoin_m2_chart.py

@@ -15,6 +15,8 @@ from datetime import datetime
 from pathlib import Path
 from typing import Tuple
 
+from scripts.constants import DB_PATH_DEFAULT
+
 import matplotlib.dates as mdates
 import matplotlib.pyplot as plt
 import pandas as pd
@@ -29,7 +31,7 @@ def fetch_series(
     end: datetime,
     btc_series: str,
     m2_series: str,
-    db_path: str | Path = Path("data/fred.db"),
+    db_path: str | Path = DB_PATH_DEFAULT,
 ) -> Tuple[pd.DataFrame, pd.DataFrame]:
     """Load Bitcoin and M2 series from a local SQLite DB."""
     df = fetch_series_db([btc_series, m2_series], start, end, db_path)
@@ -113,7 +115,10 @@ def main(argv: list[str] | None = None) -> plt.Figure:
         "--extend-years", type=int, default=1, help="years beyond end date to show"
     )
     p.add_argument(
-        "--db", type=str, default="data/fred.db", help="path to local SQLite DB"
+        "--db",
+        type=str,
+        default=str(DB_PATH_DEFAULT),
+        help="path to local SQLite DB",
     )
     p.add_argument(
         "--output", type=str, default=None, help="optional path to save the figure"

scripts/common.py

@@ -5,6 +5,8 @@ from datetime import datetime
 from pathlib import Path
 from typing import Iterable
 
+from scripts.constants import DB_PATH_DEFAULT
+
 import matplotlib.pyplot as plt
 import pandas as pd
 import sqlite3
@@ -28,7 +30,7 @@ def fetch_series_db(
     series: Iterable[str],
     start: datetime,
     end: datetime,
-    db_path: str | Path = Path("data/fred.db"),
+    db_path: str | Path = DB_PATH_DEFAULT,
 ) -> pd.DataFrame:
     """
     Load one or more FRED series from a local SQLite DB.

scripts/constants.py

@@ -0,0 +1,5 @@
+from pathlib import Path
+
+DB_PATH_DEFAULT = Path("data/fred.db")
+UNRATE = "UNRATE"
+DCOILWTICO = "DCOILWTICO"

scripts/custom_chart.py

@@ -15,6 +15,8 @@ from datetime import datetime
 from pathlib import Path
 from typing import Iterable
 
+from scripts.constants import DB_PATH_DEFAULT
+
 import matplotlib.dates as mdates
 import matplotlib.pyplot as plt
 import pandas as pd
@@ -27,7 +29,7 @@ def fetch_series_multi(
     series: Iterable[str],
     start: datetime,
     end: datetime,
-    db_path: str | Path = Path("data/fred.db"),
+    db_path: str | Path = DB_PATH_DEFAULT,
 ) -> pd.DataFrame:
     """Load one or more FRED series from a local SQLite DB."""
     return fetch_series_db(series, start, end, db_path)
@@ -63,7 +65,12 @@ def main(argv: list[str] | None = None) -> plt.Figure:
         default=datetime.today().strftime("%Y-%m-%d"),
         help="end date YYYY-MM-DD",
     )
-    p.add_argument("--db", type=str, default="data/fred.db", help="path to SQLite DB")
+    p.add_argument(
+        "--db",
+        type=str,
+        default=str(DB_PATH_DEFAULT),
+        help="path to SQLite DB",
+    )
     p.add_argument(
         "--output",
         type=str,

scripts/lagged_oil_unrate_chart_styled.py

@@ -15,6 +15,8 @@ import argparse
 from datetime import datetime
 from pathlib import Path
 
+from scripts.constants import DB_PATH_DEFAULT, UNRATE, DCOILWTICO
+
 import matplotlib.dates as mdates
 import matplotlib.pyplot as plt
 import matplotlib.ticker as mticker
@@ -36,7 +38,7 @@ from scripts.common import (
 def fetch_series(
     start: datetime,
     end: datetime,
-    db_path: str | Path = Path("data/fred.db"),
+    db_path: str | Path = DB_PATH_DEFAULT,
 ) -> tuple[pd.DataFrame, pd.DataFrame]:
     """
     Load UNRATE and DCOILWTICO from a local SQLite DB, then:
@@ -45,11 +47,11 @@ def fetch_series(
     * average WTI daily prices to month-end
     """
     # Read both series from SQLite
-    df = fetch_series_db(["UNRATE", "DCOILWTICO"], start, end, db_path)
+    df = fetch_series_db([UNRATE, DCOILWTICO], start, end, db_path)
     # Extract UNRATE and rename to 'value'
-    unrate = df[["UNRATE"]].rename(columns={"UNRATE": "value"})
+    unrate = df[[UNRATE]].rename(columns={UNRATE: "value"})
     # Extract DCOILWTICO (oil price) and rename to 'value'
-    oil = df[["DCOILWTICO"]].rename(columns={"DCOILWTICO": "value"})
+    oil = df[[DCOILWTICO]].rename(columns={DCOILWTICO: "value"})
 
     # Resample WTI to month-end average
     oil_monthly = oil.resample("M").mean()
@@ -61,9 +63,13 @@ def fetch_series(
 
 def validate_series(unrate: pd.DataFrame, oil: pd.DataFrame) -> None:
     """Run basic sanity checks on the two series."""
-    validate_dataframe(unrate, "UNRATE")        # Raises ValueError if UNRATE is empty, NaNs, or bad index
-    validate_dataframe(oil, "DCOILWTICO")       # Raises ValueError if oil is empty, NaNs, or bad index
-    validate_overlap(unrate, oil)               # Raises ValueError if no date overlap
+    validate_dataframe(
+        unrate, UNRATE
+    )  # Raises ValueError if UNRATE is empty, NaNs, or bad index
+    validate_dataframe(
+        oil, DCOILWTICO
+    )  # Raises ValueError if oil is empty, NaNs, or bad index
+    validate_overlap(unrate, oil)  # Raises ValueError if no date overlap
 
 
 # ──────────────────────────────────────────────────────────────────────────
@@ -89,7 +95,9 @@ def plot_lagged(
     common_end = min(unrate.index.max(), oil.index.max())
 
     print(f"⚠️ Using overlapping range: {common_start.date()} to {common_end.date()}")
-    print(f"  - UNRATE range: {unrate.index.min().date()} to {unrate.index.max().date()}")
+    print(
+        f"  - UNRATE range: {unrate.index.min().date()} to {unrate.index.max().date()}"
+    )
     print(f"  - OIL    range: {oil.index.min().date()} to {oil.index.max().date()}")
 
     # Trim series to common range
@@ -215,7 +223,7 @@ def main() -> plt.Figure:
     p.add_argument(
         "--db",
         type=str,
-        default="data/fred.db",
+        default=str(DB_PATH_DEFAULT),
         help="path to local FRED SQLite file",
     )
     p.add_argument(

scripts/refresh_data.py

@@ -20,13 +20,15 @@ import sqlite3
 from pandas_datareader.data import DataReader
 import pandas as pd
 
+from scripts.constants import DB_PATH_DEFAULT, UNRATE, DCOILWTICO
+
 HERE = pathlib.Path(__file__).resolve().parent
-DATA_PATH = HERE.parent / "data"
-DB_FILE = DATA_PATH / "fred.db"
+DATA_PATH = DB_PATH_DEFAULT.parent
+DB_FILE = DB_PATH_DEFAULT
 
 DEFAULT_START = "1948-01-01"  # earliest UNRATE observation
 DEFAULT_END = date.today().isoformat()
-DEFAULT_SERIES = ("UNRATE", "DCOILWTICO")
+DEFAULT_SERIES = (UNRATE, DCOILWTICO)
 
 
 def main(argv: list[str] | None = None) -> None: