ETL Classes for Data Sets (#260)

* first commit

* checkpoint

* checkpoint

* first extract module 🎉

* completed census acs etl class

* completed ejscreen etl

* completed etl

* score generation ready

* improving census load and separation

* score generation working 🎉

* completed etls

* new score generation

* PR reviews

* run specific etl; starting docstrings

* docstrings work

* more docstrings

* completed docstrings

* adding pyenv version

* more reasonable poetry req for python

* PR comments

score/etl/sources/ejscreen/etl.py

@@ -1 +1,39 @@
-# https://gaftp.epa.gov/EJSCREEN/2020/EJSCREEN_2020_StatePctile.csv.zip
+import pandas as pd
+
+from etl.base import ExtractTransformLoad
+from utils import get_module_logger
+
+logger = get_module_logger(__name__)
+
+
+class EJScreenETL(ExtractTransformLoad):
+    def __init__(self):
+        self.EJSCREEN_FTP_URL = (
+            "https://gaftp.epa.gov/EJSCREEN/2020/EJSCREEN_2020_StatePctile.csv.zip"
+        )
+        self.EJSCREEN_CSV = self.TMP_PATH / "EJSCREEN_2020_StatePctile.csv"
+        self.CSV_PATH = self.DATA_PATH / "dataset" / "ejscreen_2020"
+        self.df: pd.DataFrame
+
+    def extract(self) -> None:
+        logger.info(f"Downloading EJScreen Data")
+        super().extract(
+            self.EJSCREEN_FTP_URL,
+            self.TMP_PATH,
+        )
+
+    def transform(self) -> None:
+        logger.info(f"Transforming EJScreen Data")
+        self.df = pd.read_csv(
+            self.EJSCREEN_CSV,
+            dtype={"ID": "string"},
+            # EJSCREEN writes the word "None" for NA data.
+            na_values=["None"],
+            low_memory=False,
+        )
+
+    def load(self) -> None:
+        logger.info(f"Saving EJScreen CSV")
+        # write nationwide csv
+        self.CSV_PATH.mkdir(parents=True, exist_ok=True)
+        self.df.to_csv(self.CSV_PATH / f"usa.csv", index=False)