import keyword
import os
import re
from glob import glob
from typing import Any, Dict, List, Mapping, Optional, Sequence, Tuple, cast
import yaml
import dagster._check as check
import dagster._seven as seven
from dagster._core.errors import DagsterInvalidDefinitionError, DagsterInvariantViolationError
from dagster._core.storage.tags import check_reserved_tags
from dagster._utils import frozentags
from dagster._utils.yaml_utils import merge_yaml_strings, merge_yamls
DEFAULT_OUTPUT = "result"
DEFAULT_GROUP_NAME = "default" # asset group_name used when none is provided
DEFAULT_IO_MANAGER_KEY = "io_manager"
DISALLOWED_NAMES = set(
[
"context",
"conf",
"config",
"meta",
"arg_dict",
"dict",
"input_arg_dict",
"output_arg_dict",
"int",
"str",
"float",
"bool",
"input",
"output",
"type",
]
+ list(keyword.kwlist) # just disallow all python keywords
)
VALID_NAME_REGEX_STR = r"^[A-Za-z0-9_]+$"
VALID_NAME_REGEX = re.compile(VALID_NAME_REGEX_STR)
class NoValueSentinel:
"""Sentinel value to distinguish unset from None."""
def has_valid_name_chars(name: str) -> bool:
return bool(VALID_NAME_REGEX.match(name))
def check_valid_name(name: str, allow_list: Optional[List[str]] = None) -> str:
check.str_param(name, "name")
if allow_list and name in allow_list:
return name
if name in DISALLOWED_NAMES:
raise DagsterInvalidDefinitionError(
f'"{name}" is not a valid name in Dagster. It conflicts with a Dagster or python'
" reserved keyword."
)
check_valid_chars(name)
check.invariant(is_valid_name(name))
return name
def check_valid_chars(name: str):
if not has_valid_name_chars(name):
raise DagsterInvalidDefinitionError(
f'"{name}" is not a valid name in Dagster. Names must be in regex'
f" {VALID_NAME_REGEX_STR}."
)
def is_valid_name(name: str) -> bool:
check.str_param(name, "name")
return name not in DISALLOWED_NAMES and has_valid_name_chars(name)
def _kv_str(key: object, value: object) -> str:
return f'{key}="{repr(value)}"'
def struct_to_string(name: str, **kwargs: object) -> str:
# Sort the kwargs to ensure consistent representations across Python versions
props_str = ", ".join([_kv_str(key, value) for key, value in sorted(kwargs.items())])
return "{name}({props_str})".format(name=name, props_str=props_str)
def validate_tags(tags: Optional[Mapping[str, Any]], allow_reserved_tags=True) -> frozentags:
valid_tags = {}
for key, value in check.opt_mapping_param(tags, "tags", key_type=str).items():
if not isinstance(value, str):
valid = False
err_reason = 'Could not JSON encode value "{}"'.format(value)
str_val = None
try:
str_val = seven.json.dumps(value)
err_reason = (
'JSON encoding "{json}" of value "{val}" is not equivalent to original value'
.format(json=str_val, val=value)
)
valid = seven.json.loads(str_val) == value
except Exception:
pass
if not valid:
raise DagsterInvalidDefinitionError(
'Invalid value for tag "{key}", {err_reason}. Tag values must be strings '
"or meet the constraint that json.loads(json.dumps(value)) == value.".format(
key=key, err_reason=err_reason
)
)
valid_tags[key] = str_val
else:
valid_tags[key] = value
if not allow_reserved_tags:
check_reserved_tags(valid_tags)
return frozentags(valid_tags)
def validate_group_name(group_name: Optional[str]) -> str:
"""Ensures a string name is valid and returns a default if no name provided."""
if group_name:
check_valid_chars(group_name)
return group_name
return DEFAULT_GROUP_NAME
[docs]def config_from_files(config_files: Sequence[str]) -> Mapping[str, Any]:
"""Constructs run config from YAML files.
Args:
config_files (List[str]): List of paths or glob patterns for yaml files
to load and parse as the run config.
Returns:
Dict[str, Any]: A run config dictionary constructed from provided YAML files.
Raises:
FileNotFoundError: When a config file produces no results
DagsterInvariantViolationError: When one of the YAML files is invalid and has a parse
error.
"""
config_files = check.opt_sequence_param(config_files, "config_files")
filenames = []
for file_glob in config_files or []:
globbed_files = glob(file_glob)
if not globbed_files:
raise DagsterInvariantViolationError(
'File or glob pattern "{file_glob}" for "config_files" produced no results.'.format(
file_glob=file_glob
)
)
filenames += [os.path.realpath(globbed_file) for globbed_file in globbed_files]
try:
run_config = merge_yamls(filenames)
except yaml.YAMLError as err:
raise DagsterInvariantViolationError(
f"Encountered error attempting to parse yaml. Parsing files {filenames} "
f"loaded by file/patterns {config_files}."
) from err
return check.is_dict(cast(Dict[str, object], run_config), key_type=str)
[docs]def config_from_yaml_strings(yaml_strings: Sequence[str]) -> Mapping[str, Any]:
"""Static constructor for run configs from YAML strings.
Args:
yaml_strings (List[str]): List of yaml strings to parse as the run config.
Returns:
Dict[Str, Any]: A run config dictionary constructed from the provided yaml strings
Raises:
DagsterInvariantViolationError: When one of the YAML documents is invalid and has a
parse error.
"""
yaml_strings = check.sequence_param(yaml_strings, "yaml_strings", of_type=str)
try:
run_config = merge_yaml_strings(yaml_strings)
except yaml.YAMLError as err:
raise DagsterInvariantViolationError(
f"Encountered error attempting to parse yaml. Parsing YAMLs {yaml_strings} "
) from err
return check.is_dict(cast(Dict[str, object], run_config), key_type=str)
[docs]def config_from_pkg_resources(pkg_resource_defs: Sequence[Tuple[str, str]]) -> Mapping[str, Any]:
"""Load a run config from a package resource, using :py:func:`pkg_resources.resource_string`.
Example:
.. code-block:: python
config_from_pkg_resources(
pkg_resource_defs=[
('dagster_examples.airline_demo.environments', 'local_base.yaml'),
('dagster_examples.airline_demo.environments', 'local_warehouse.yaml'),
],
)
Args:
pkg_resource_defs (List[(str, str)]): List of pkg_resource modules/files to
load as the run config.
Returns:
Dict[Str, Any]: A run config dictionary constructed from the provided yaml strings
Raises:
DagsterInvariantViolationError: When one of the YAML documents is invalid and has a
parse error.
"""
import pkg_resources # expensive, import only on use
pkg_resource_defs = check.sequence_param(pkg_resource_defs, "pkg_resource_defs", of_type=tuple)
try:
yaml_strings = [
pkg_resources.resource_string(*pkg_resource_def).decode("utf-8")
for pkg_resource_def in pkg_resource_defs
]
except (ModuleNotFoundError, FileNotFoundError, UnicodeDecodeError) as err:
raise DagsterInvariantViolationError(
"Encountered error attempting to parse yaml. Loading YAMLs from "
f"package resources {pkg_resource_defs}."
) from err
return config_from_yaml_strings(yaml_strings=yaml_strings)