# Error Collector
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Collects raised error during with statement.
## Features
In some cases we don't want to raise an error immediately.
For example, case when return error HTTP response to client
after validating whole HTTP POST data.
This package helps to collect error.
## Installation
```console
pip install errorcollector
```
## Usage
### MultipleErrorCollector
Let's say, there are data model which has single property.
Before process this data model, we want to validate property.
Ex:
```python
from yourproduct.exceptions import ConvertError
class PostDataModel:
def __init__(self, property_a_string: str, property_b_string: str):
self._property_a_string = property_a_string
self._property_b_string = property_b_string
self.list_error = None
def validate(self) -> bool:
self.stock_convert_error(
lambda: self.property_a_int,
f"Property string A couldn't be converted to integer. Property string = {self._property_a_string}"
)
self.stock_convert_error(
lambda: self.property_b_int,
f"Property string B couldn't be converted to integer. Property string = {self._property_b_string}"
)
return bool(self.list_error)
def stock_convert_error(self, method: Callable[[], Any], message: str) -> None:
with MultipleErrorCollector(ConvertError, message, self.list_error):
return method()
@property
def property_a_int() -> int:
"""May raise ValueError"""
return int(self._property_a_string)
@property
def property_b_int() -> int:
"""May raise ValueError"""
return int(self._property_b_string)
```
When we call method `validate()`, even if `ValueError` occurs,
the exception is not raised and execution does not stop.
When `method()` in method `stock_convert_error()` raises `ValueError`,
`ConvertError` which is set raised `ValueError` into `__cause__` is set
into property `self.list_error`.
We can check details of error after validate.
### SingleErrorCollector
This is single version of Error Collector.
This may be useful in case when need to handle
multiple cases and singular cases in an integrated method by polymorphism.
Ex:
```python
from yourproduct.exceptions import ConvertError
class PostDataModel:
def __init__(self, property_string: str):
self._property_string = property_string
self.convert_error = None
def validate(self) -> bool:
self.stock_convert_error(
lambda: self.property_int,
f"Property string couldn't be converted to integer. Property string = {self._property_string}"
)
return self.convert_error is not None
def stock_convert_error(self, method: Callable[[], Any], message: str) -> None:
error_collector = SingleErrorCollector(ConvertError, message)
with error_collector:
method()
self.convert_error = error_collector.error
@property
def property_int() -> int:
"""May raise ValueError"""
return int(self._property_string)
```