Support reading apply configurations from stdin

Author: r4victor

src/dstack/_internal/cli/commands/apply.py

@@ -1,10 +1,10 @@
 import argparse
-from pathlib import Path
 
 from argcomplete import FilesCompleter
 
 from dstack._internal.cli.commands import APIBaseCommand
 from dstack._internal.cli.services.configurators import (
+    APPLY_STDIN_NAME,
     get_apply_configurator_class,
     load_apply_configuration,
 )
@@ -40,9 +40,12 @@ def _register(self):
         self._parser.add_argument(
             "-f",
             "--file",
-            type=Path,
             metavar="FILE",
-            help="The path to the configuration file. Defaults to [code]$PWD/.dstack.yml[/]",
+            help=(
+                "The path to the configuration file."
+                " Specify [code]-[/] to read configuration from stdin."
+                " Defaults to [code]$PWD/.dstack.yml[/]"
+            ),
             dest="configuration_file",
         ).completer = FilesCompleter(allowednames=["*.yml", "*.yaml"])
         self._parser.add_argument(
@@ -104,6 +107,10 @@ def _command(self, args: argparse.Namespace):
                 return
 
             super()._command(args)
+            if not args.yes and args.configuration_file == APPLY_STDIN_NAME:
+                # FIXME: probably does not work since dstack apply can ask questions futher,
+                # e.g. whether to terminate a resource on ctrl+c or not
+                raise CLIError("Cannot read configuration from stdin if -y/--yes is not specified")
             if args.repo and args.no_repo:
                 raise CLIError("Either --repo or --no-repo can be specified")
             repo = None

src/dstack/_internal/cli/services/configurators/__init__.py

@@ -1,3 +1,4 @@
+import sys
 from pathlib import Path
 from typing import Dict, Optional, Tuple, Type
 
@@ -20,6 +21,9 @@
     parse_apply_configuration,
 )
 
+APPLY_STDIN_NAME = "-"
+
+
 apply_configurators_mapping: Dict[ApplyConfigurationType, Type[BaseApplyConfigurator]] = {
     cls.TYPE: cls
     for cls in [
@@ -62,6 +66,8 @@ def load_apply_configuration(
             raise ConfigurationError(
                 "No configuration file specified via `-f` and no default .dstack.yml configuration found"
             )
+    elif configuration_file == APPLY_STDIN_NAME:
+        configuration_path = sys.stdin.fileno()
     else:
         configuration_path = Path(configuration_file)
         if not configuration_path.exists():
@@ -71,4 +77,6 @@ def load_apply_configuration(
             conf = parse_apply_configuration(yaml.safe_load(f))
     except OSError:
         raise ConfigurationError(f"Failed to load configuration from {configuration_path}")
+    if isinstance(configuration_path, int):
+        return APPLY_STDIN_NAME, conf
     return str(configuration_path.absolute().relative_to(Path.cwd())), conf