Changes as per code review.

api/routes/__init__.py

@@ -1,5 +1,3 @@
-import os
-
 from api.routes.sample import router as sample_router
 from api.routes.imports import router as import_router
 from api.routes.analysis import router as analysis_router

api/routes/billing.py

@@ -113,7 +113,7 @@ async def get_datasets(
 
 
 @router.get(
-    '/sequencing_types',
+    '/sequencing-types',
     response_model=list[str],
     operation_id='getSequencingTypes',
 )
@@ -151,7 +151,7 @@ async def get_stages(
 
 
 @router.get(
-    '/sequencing_groups',
+    '/sequencing-groups',
     response_model=list[str],
     operation_id='getSequencingGroups',
 )
@@ -170,7 +170,7 @@ async def get_sequencing_groups(
 
 
 @router.get(
-    '/invoice_months',
+    '/invoice-months',
     response_model=list[str],
     operation_id='getInvoiceMonths',
 )

api/utils/dates.py

@@ -15,7 +15,11 @@ def parse_date_only_string(d: str | None) -> date | None:
 
 
 def get_invoice_month_range(convert_month: date) -> tuple[date, date]:
-    """Get the start and end date of the invoice month for a given date"""
+    """
+    Get the start and end date of the invoice month for a given date
+    Start and end date are used mostly for optimising BQ queries
+    All our BQ tables/views are partitioned by day
+    """
     first_day = convert_month.replace(day=1)
 
     # Grab the first day of invoice month then subtract INVOICE_DAY_DIFF days
@@ -34,3 +38,23 @@ def get_invoice_month_range(convert_month: date) -> tuple[date, date]:
     )
 
     return start_day, last_day
+
+
+def reformat_datetime(
+    in_date: str | None, in_format: str, out_format: str
+) -> str | None:
+    """
+    Reformat datetime as string to another string format
+    This function take string as input and return string as output
+    """
+    if not in_date:
+        return None
+
+    try:
+        result = datetime.strptime(
+            in_date, in_format
+        )
+        return result.strftime(out_format)
+
+    except Exception as excep:
+        raise ValueError(f'Date could not be converted: {in_date}') from excep