Ersilia Catalog Bug when no models are available (#1175)

* fixed error that occurs when no local model is available

* implenting requested changes

---------

Co-authored-by: Dhanshree Arora <DhanshreeA@users.noreply.github.com>

ersilia/cli/commands/catalog.py

@@ -32,7 +32,8 @@ def catalog_cmd():
  def catalog(local=False, file_name=None, browser=False, more=False):
  if local is True and browser is True:
  click.echo(
- "You cannot show the local model catalog in the browser", fg="red"
+ "You cannot show the local model catalog in the browser",
+ fg="red",
  )
  if more:
  only_identifier = False
@@ -42,16 +43,19 @@ def catalog(local=False, file_name=None, browser=False, more=False):
  if browser:
  mc.airtable()
  return
- if local:
- if file_name is None:
- catalog = mc.local().as_json()
- else:
- mc.local().write(file_name)
- catalog = None
+ catalog_table = mc.local() if local else mc.hub()
+ if local and not catalog_table.data:
+ click.echo(
+ click.style(
+ "No local model is available. Please fetch a model by running 'ersilia fetch ...'",
+ fg="red",
+ )
+ )
+ return
+ if file_name is None:
+ catalog = catalog_table.as_json()
  else:
- if file_name is None:
- catalog = mc.hub().as_json()
- else:
- mc.hub().write(file_name)
- catalog = None
+ catalog_table.write(file_name)
+ catalog = None
+
  click.echo(catalog)

ersilia/hub/content/catalog.py

@@ -202,7 +202,7 @@ def local(self):
  columns = ["Identifier", "Slug", "Title", "Status", "Input", "Output", "Service Class"]
  logger.info("Found {0} models".format(len(R)))
  if len(R) == 0:
- return None
+ return CatalogTable(data=[], columns=columns)
  return CatalogTable(data=R, columns=columns)
 
  def bentoml(self):