gufo.err.err

Define Err class and err singleton.

Attributes:

Name	Type	Description
err		Err singletone.

Err

Bases: object

Error handling singleton.

Example

from gufo.err import err

err.setup()

__default_middleware(format=None, error_info_path=None, error_info_compress=None)

Get default middleware chain.

Parameters:

Name	Type	Description	Default
format	Optional[str]	traceback format. See TracebackMiddleware for details. Do not configure tracebacks if None.	None
error_info_path	Optional[str]	Directory path to write error info. See ErrorInfoMiddleware for details. Do not configure middleware if None.	None
error_info_compress	Optional[str]	Error info compression algorithm. Used along with error_info_path.	None

__fingerprint(t, v, stack)

Calculate the error fingerprint.

Calculate error fingerprint for given exception and the stack. Fingerprint is stable for repeating conditions.

Parameters:

Name	Type	Description	Default
t	Type[BaseException]	Exception type.	required
v	BaseException	Exception instance:	required
stack	List[FrameInfo]	Current stack.	required

Returns:

Type	Description
UUID	Error fingerprint as UUID.

__must_die(t, v, tb)

Check if the error is fatal and the process must die.

Process fail-fast sequence and return True if the process must die quickly.

__process(t, v, tb=None)

Process given exception context.

Called either from .process() or as sys.excepthook for unhandled exceptions.

Parameters:

Name	Type	Description	Default
t	Type[BaseException]	Exception type.	required
v	BaseException	Exception value.	required
tb	Optional[TracebackType]	Traceback frame.	None

Raises:

Type	Description
RuntimeError	If setup() is not called.

__run_middleware(err_info)

Process all the middleware.

Parameters:

Name	Type	Description	Default
err_info	ErrorInfo	Filled ErrorInfo structure	required

add_fail_fast(ff)

Add fail-fast handler to the end of the chain.

Parameters:

Name	Type	Description	Default
ff	BaseFailFast	BaseFailFast instance.	required

Raises:

Type	Description
ValueError	If ff is not BaseFailFast instance.

add_middleware(mw)

Add middleware to the end of the chain.

Parameters:

Name	Type	Description	Default
mw	BaseMiddleware	BaseMiddleware instance	required

Raises:

Type	Description
ValueError	If mw is not BaseMiddleware instance.

iter_fingerprint_parts(t, v, stack)

Iterate over the fingerprint parts.

Iterable to yield all fingerprint parts. May be overriden in subclasses.

Parameters:

Name	Type	Description	Default
t	Type[BaseException]	Exception type.	required
v	BaseException	Exception instance:	required
stack	List[FrameInfo]	Current stack.	required

Returns:

Type	Description
Iterable[str]	Iterable of strings.

process()

Process current exception context in the fenced code block.

Example

from gufo.err import err

...
try:
    my_function()
except Exception:
    err.process()

setup(*, catch_all=False, root_module=None, name=DEFAULT_NAME, version=DEFAULT_VERSION, hash=DEFAULT_HASH, fail_fast=None, fail_fast_code=DEFAULT_EXIT_CODE, middleware=None, format='terse', error_info_path=None, error_info_compress=None)

Setup error handling singleton.

Must be called only once.

Parameters:

Name	Type	Description	Default
catch_all	bool	Install global system exception hook.	False
name	str	Application or service name.	DEFAULT_NAME
version	str	Application or service version.	DEFAULT_VERSION
root_module	Optional[str]	Top-level application module/namespace for split stack fingerprinting. Topmost frame from the root or the nested modules will be considered in the error fingerprint.	None
hash	str	Fingerprint hashing function name. Available functions are: sha256, sha3_512, blake2s, sha3_224, md5, sha384, sha3_256, shake_256, blake2b, sha224, shake_128, sha3_384, sha1, sha512. Refer to the Python's hashlib for details.	DEFAULT_HASH
fail_fast	Optional[Iterable[BaseFailFast]]	Iterable of BaseFailFast instances for fail-fast detection. Process will terminate with fail_fast_code error code if any of instances in the chain will return True.	None
fail_fast_code	int	System exit code on fail-fast termination.	DEFAULT_EXIT_CODE
middleware	Optional[Iterable[BaseMiddleware]]	Iterable of BaseMiddleware instances for error processing middleware. Instances are evaluated in the order of appearance.	None
format	Optional[str]	If not None install TracebackMiddleware for given output format.	'terse'
error_info_path	Optional[str]	If not None install ErrorInfoMiddleware. error_info_path should point to a writable directories, in which the error info files to be written.	None
error_info_compress	Optional[str]	Used only with error_info_path. Set error info compression method. One of: None - do not compress gz - GZip bz2 - BZip2 xz - LZMA/xz	None

Returns:

Type	Description
Err	Err instance.

Raises:

Type	Description
RuntimeError	When called twice.
ValueError	On configuration parameters error.