Add ability to get a list of supported pipeline tasks (#14732)

src/transformers/commands/run.py

@@ -14,7 +14,7 @@
 
 from argparse import ArgumentParser
 
-from ..pipelines import SUPPORTED_TASKS, TASK_ALIASES, Pipeline, PipelineDataFormat, pipeline
+from ..pipelines import Pipeline, PipelineDataFormat, get_supported_tasks, pipeline
 from ..utils import logging
 from . import BaseTransformersCLICommand
 
@@ -63,9 +63,7 @@ def __init__(self, nlp: Pipeline, reader: PipelineDataFormat):
     @staticmethod
     def register_subcommand(parser: ArgumentParser):
         run_parser = parser.add_parser("run", help="Run a pipeline through the CLI")
-        run_parser.add_argument(
-            "--task", choices=list(SUPPORTED_TASKS.keys()) + list(TASK_ALIASES.keys()), help="Task to run"
-        )
+        run_parser.add_argument("--task", choices=get_supported_tasks(), help="Task to run")
         run_parser.add_argument("--input", type=str, help="Path to the file to use for inference")
         run_parser.add_argument("--output", type=str, help="Path to the file that will be used post to write results.")
         run_parser.add_argument("--model", type=str, help="Name or path to the model to instantiate.")

src/transformers/commands/serving.py

@@ -15,7 +15,7 @@
 from argparse import ArgumentParser, Namespace
 from typing import Any, List, Optional
 
-from ..pipelines import SUPPORTED_TASKS, TASK_ALIASES, Pipeline, pipeline
+from ..pipelines import Pipeline, get_supported_tasks, pipeline
 from ..utils import logging
 from . import BaseTransformersCLICommand
 
@@ -104,7 +104,7 @@ def register_subcommand(parser: ArgumentParser):
         serve_parser.add_argument(
             "--task",
             type=str,
-            choices=list(SUPPORTED_TASKS.keys()) + list(TASK_ALIASES.keys()),
+            choices=get_supported_tasks(),
             help="The task to run the pipeline on",
         )
         serve_parser.add_argument("--host", type=str, default="localhost", help="Interface the server will listen on.")

src/transformers/pipelines/__init__.py

@@ -20,7 +20,7 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 import warnings
-from typing import TYPE_CHECKING, Any, Dict, Optional, Tuple, Union
+from typing import TYPE_CHECKING, Any, Dict, List, Optional, Tuple, Union
 
 from ..configuration_utils import PretrainedConfig
 from ..feature_extraction_utils import PreTrainedFeatureExtractor
@@ -252,6 +252,15 @@
 }
 
 
+def get_supported_tasks() -> List[str]:
+    """
+    Returns a list of supported task strings.
+    """
+    supported_tasks = list(SUPPORTED_TASKS.keys()) + list(TASK_ALIASES.keys())
+    supported_tasks.sort()
+    return supported_tasks
+
+
 def get_task(model: str, use_auth_token: Optional[str] = None) -> str:
     tmp = io.BytesIO()
     headers = {}
@@ -320,9 +329,7 @@ def check_task(task: str) -> Tuple[Dict, Any]:
             return targeted_task, (tokens[1], tokens[3])
         raise KeyError(f"Invalid translation task {task}, use 'translation_XX_to_YY' format")
 
-    raise KeyError(
-        f"Unknown task {task}, available tasks are {list(SUPPORTED_TASKS.keys()) + ['translation_XX_to_YY']}"
-    )
+    raise KeyError(f"Unknown task {task}, available tasks are {get_supported_tasks() + ['translation_XX_to_YY']}")
 
 
 def pipeline(