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import json
import boto3
import re
import pandas as pd
import pyarrow as pa
import pyarrow.parquet as pq
from src.extract_lambda import extract_bucket
from src.fact_purchase_table import *
from src.fact_sales_order import create_dim_staff, create_dim_design, create_fact_sales_order
tables = [
"sales_order",
"transaction",
"payment",
"counterparty",
"address",
"staff",
"purchase_order",
"department",
"currency",
"design",
"payment_type",
]
def lambda_handler(event, context):
dict_of_df = read_from_s3_subfolder_to_df(tables, extract_bucket(), client=boto3.client("s3"))
common_df_list = [create_dim_counterparty(dict_of_df),
create_dim_date(dict_of_df),
create_dim_location(dict_of_df),
create_dim_currency(dict_of_df),
create_dim_staff(dict_of_df)]
create_fact_purchase_order()
f_sales_list = [create_fact_sales_order(),
create_dim_design()]
'''
#dict{
sales_schema: {
Table_name: df_value,
...}
payment_schema:
Table_name: df_value,
...}
purchase_schema:
Table_name: df_value,
...}
}
for schema in dict:
for table_name, df_value in schema.items():
parquet_file = df_value.to_parquet(f'{table_name}.parquet', engine='pyarrow'/'fastparquet'(?)) #we don't know the engine
s3_key = datetime.strftime(
datetime.today(), f"{schema}/%Y/%m/%d/{table_name}_%H:%M:%S.parquet"
)
client.upload_file(
parquet_file, transform_bucket(), s3_key)
##might need seperate function for easier testing##
'''
def read_from_s3_subfolder_to_df(tables, bucket, client=boto3.client("s3")):
table_dfs = {}
for table in tables:
response = client.list_objects_v2(Bucket=bucket, Prefix=table)
list_of_keys = [
"s3://" + bucket + "/" + object["Key"] for object in response["Contents"]
]
list_of_df = [pd.read_csv(key) for key in list_of_keys]
table_dfs[table] = pd.concat(list_of_df)
return table_dfs
def transform_bucket(client=boto3.client("s3")):
response = client.list_buckets()
bucket_filter = [
bucket["Name"] for bucket in response["Buckets"] if "transform" in bucket["Name"]
]
return bucket_filter[0]
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