Source code for dagster.core.definitions.utils

import keyword
import os
import re
from glob import glob
from typing import Any, Dict, List, Optional, Tuple

import pkg_resources
import yaml

from dagster import check, seven
from dagster.core.errors import DagsterInvalidDefinitionError, DagsterInvariantViolationError
from dagster.utils import frozentags
from dagster.utils.yaml_utils import merge_yaml_strings, merge_yamls

DEFAULT_OUTPUT = "result"

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):
    return bool(VALID_NAME_REGEX.match(name))


def check_valid_name(name: str):
    check.str_param(name, "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.'
        )

    if not has_valid_name_chars(name):
        raise DagsterInvalidDefinitionError(
            f'"{name}" is not a valid name in Dagster. Names must be in regex {VALID_NAME_REGEX_STR}.'
        )

    check.invariant(is_valid_name(name))
    return name


def is_valid_name(name):
    check.str_param(name, "name")

    return name not in DISALLOWED_NAMES and has_valid_name_chars(name)


def _kv_str(key, value):
    return '{key}="{value}"'.format(key=key, value=repr(value))


def struct_to_string(name, **kwargs):
    # 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[Dict[str, Any]]) -> Dict[str, Any]:
    valid_tags = {}
    for key, value in check.opt_dict_param(tags, "tags", key_type=str).items():
        if not isinstance(value, str):
            valid = False
            err_reason = 'Could not JSON encode value "{}"'.format(value)
            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

    return frozentags(valid_tags)


[docs]def config_from_files(config_files: List[str]) -> Dict[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_list_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 run_config
[docs]def config_from_yaml_strings(yaml_strings: List[str]) -> Dict[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.list_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 run_config
[docs]def config_from_pkg_resources(pkg_resource_defs: List[Tuple[str, str]]) -> Dict[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. """ pkg_resource_defs = check.list_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)