Handling error when reference not found using conan download (#5399)

* Added required = True to subparsers in order to print error message in Py2 and Py3.

* sync

* basic concurrent upload at reference level with futures

* revert changes

* add line

* output error message when conan download tries to download
a reference that is not in the remote

* catch NotFoundException in correct place

* re-raise NotFoundException

* raise RecipeNotFound exception

* test error is raised when the reference is not found in server

conans/client/cmd/download.py

@@ -1,7 +1,7 @@
 from conans.client.output import ScopedOutput
 from conans.client.source import complete_recipe_sources
 from conans.model.ref import ConanFileReference, PackageReference
-
+from conans.errors import NotFoundException, RecipeNotFoundException
 
 def download(ref, package_ids, remote, recipe, remote_manager,
              cache, out, recorder, loader, hook_manager, remotes):
@@ -11,7 +11,11 @@ def download(ref, package_ids, remote, recipe, remote_manager,
 
     hook_manager.execute("pre_download", reference=ref, remote=remote)
 
-    ref = remote_manager.get_recipe(ref, remote)
+    try:
+        ref = remote_manager.get_recipe(ref, remote)
+    except NotFoundException:
+        raise RecipeNotFoundException(ref)
+
     with cache.package_layout(ref).update_metadata() as metadata:
         metadata.recipe.remote = remote.name
 

conans/test/functional/command/download_test.py

@@ -195,4 +195,11 @@ def download_package_argument_test(self):
         # Check at conanfile.py is downloaded
         self.assertTrue(os.path.exists(package_layout.conanfile()))
         # Check package folder created
-        self.assertTrue(os.path.exists(package_folder))
+        self.assertTrue(os.path.exists(package_folder))
+
+    def download_not_found_reference_test(self):
+        server = TestServer()
+        servers = {"default": server}
+        client = TurboTestClient(servers=servers, users={"default": [("lasote", "mypass")]})
+        client.run("download pkg/0.1@lasote/stable", assert_error=True)
+        self.assertIn("ERROR: Recipe not found: 'pkg/0.1@lasote/stable'", client.out)