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[【原文链接】Pytest----如何通过filterwarnings配置不显示告警或将告警报错](http://devops-dev.com/article/470)

首先在脚本中人工抛出一条告警，测试代码如下所示：
```python
import pytest
import warnings

def test_demo1():
    print("in test_demo1 ...")
    warnings.warn(SyntaxWarning("warning，used to test..."))
    assert 1==1
```
执行结果如下所示，即这里在执行结果中也显示了一条告警信息。
```bash
(demo-HCIhX0Hq) E:\demo>pytest -s
=================== test session starts ===================
platform win32 -- Python 3.7.9, pytest-7.2.0, pluggy-1.0.0
rootdir: E:\demo
plugins: assume-2.4.3, rerunfailures-10.2
collected 1 item

test_demo.py in test_demo1 ...
.

==================== warnings summary =====================
test_demo.py::test_demo1
  E:\demo\test_demo.py:7: SyntaxWarning: warning，used to test...
    warnings.warn(SyntaxWarning("warning，used to test..."))

-- Docs: https://docs.pytest.org/en/stable/how-to/capture-warnings.html
============== 1 passed, 1 warning in 0.02s ===============

(demo-HCIhX0Hq) E:\demo>
```
在脚本中可以通过filterwarnings来配置告警信息的处理方式，比如将其忽略不显示，则代码如下，即此时在测试函数中加一个装饰器装饰，在装饰器中使用ignore，注意当按照告警类型忽略不显示的时候，ignore后面是两个冒号。
```python
import pytest
import warnings

@pytest.mark.filterwarnings("ignore::SyntaxWarning")
def test_demo1():
    print("in test_demo1 ...")
    warnings.warn(SyntaxWarning("warning，used to test..."))
    assert 1==1
```
执行结果如下，即不再有告警信息。
```bash
(demo-HCIhX0Hq) E:\demo>pytest -s
=================== test session starts ===================
platform win32 -- Python 3.7.9, pytest-7.2.0, pluggy-1.0.0
rootdir: E:\demo
plugins: assume-2.4.3, rerunfailures-10.2
collected 1 item

test_demo.py in test_demo1 ...
.

==================== 1 passed in 0.02s ====================

(demo-HCIhX0Hq) E:\demo>
```
同理，若将告警转换为报错，则只需要将代码中的装饰器中的ignore修改为error即可，如下：
```python
import pytest
import warnings

@pytest.mark.filterwarnings("error::SyntaxWarning")
def test_demo1():
    print("in test_demo1 ...")
    warnings.warn(SyntaxWarning("warning，used to test..."))
    assert 1==1
```
执行结果如下，可以看到此时用例失败了，原因就是这个告警。
```bash
(demo-HCIhX0Hq) E:\demo>pytest -s
=================== test session starts ===================
platform win32 -- Python 3.7.9, pytest-7.2.0, pluggy-1.0.0
rootdir: E:\demo
plugins: assume-2.4.3, rerunfailures-10.2
collected 1 item

test_demo.py in test_demo1 ...
F

======================== FAILURES =========================
_______________________ test_demo1 ________________________

@pytest.mark.filterwarnings("error::SyntaxWarning")
    def test_demo1():
        print("in test_demo1 ...")
>       warnings.warn(SyntaxWarning("warning，used to test..."))
E       SyntaxWarning: warning，used to test...

test_demo.py:7: SyntaxWarning
================= short test summary info =================
FAILED test_demo.py::test_demo1 - SyntaxWarning: warning，used to test...
==================== 1 failed in 0.07s ====================

(demo-HCIhX0Hq) E:\demo>
```
除此以外，还可以通过对告警信息进行正则匹配，比如当使用ignore时，此时ignore后面只跟一个冒号，冒号后面的即对告警信息的正则表达式，比如如下代码，即test_demo1中匹配告警信息中有test字符的就忽略，而test_demo2中则匹配告警信息中有demo字符的忽略，从代码分析，显然test_demo2中的告警信息无法匹配，即按照理论分析，test_demo1中的告警会忽略不显示，而test_demo2中的告警则会显示。
```python
import pytest
import warnings

@pytest.mark.filterwarnings("ignore:.*test.*")
def test_demo1():
    print("in test_demo1 ...")
    warnings.warn(SyntaxWarning("warning，used to test..."))
    assert 1==1
    
@pytest.mark.filterwarnings("ignore:.*demo.*")
def test_demo2():
    print("in test_demo2 ...")
    warnings.warn(SyntaxWarning("warning，used to test..."))
    assert 1==1
```
执行结果如下，执行结果确实如此，即test_demo2中的告警继续报出来了，而test_demo1中的告警并未显示。
```bash
(demo-HCIhX0Hq) E:\demo>pytest -s
=================== test session starts ===================
platform win32 -- Python 3.7.9, pytest-7.2.0, pluggy-1.0.0
rootdir: E:\demo
plugins: assume-2.4.3, rerunfailures-10.2
collected 2 items

test_demo.py in test_demo1 ...
.in test_demo2 ...
.

==================== warnings summary =====================
test_demo.py::test_demo2
  E:\demo\test_demo.py:13: SyntaxWarning: warning，used to test...
    warnings.warn(SyntaxWarning("warning，used to test..."))

-- Docs: https://docs.pytest.org/en/stable/how-to/capture-warnings.html
============== 2 passed, 1 warning in 0.02s ===============

(demo-HCIhX0Hq) E:\demo>
```
同理，将告警转换为报错信息，也是同样支持正则表达式的，比如如下代码：
```python
import pytest
import warnings

@pytest.mark.filterwarnings("error:.*test.*")
def test_demo1():
    print("in test_demo1 ...")
    warnings.warn(SyntaxWarning("warning，used to test..."))
    assert 1==1

@pytest.mark.filterwarnings("error:.*demo.*")
def test_demo2():
    print("in test_demo2 ...")
    warnings.warn(SyntaxWarning("warning，used to test..."))
    assert 1==1
```
执行结果如下，显然test_demo1中的告警与正则表达匹配，因此报错了，而test_demo2中的告警并未匹配到正则表达式，因此不会报错，所以继续报出了告警信息。
```bash
(demo-HCIhX0Hq) E:\demo>pytest -s
=================== test session starts ===================
platform win32 -- Python 3.7.9, pytest-7.2.0, pluggy-1.0.0
rootdir: E:\demo
plugins: assume-2.4.3, rerunfailures-10.2
collected 2 items

test_demo.py in test_demo1 ...
Fin test_demo2 ...
.

======================== FAILURES =========================
_______________________ test_demo1 ________________________

@pytest.mark.filterwarnings("error:.*test.*")
    def test_demo1():
        print("in test_demo1 ...")
>       warnings.warn(SyntaxWarning("warning，used to test..."))
E       SyntaxWarning: warning，used to test...

test_demo.py:7: SyntaxWarning
==================== warnings summary =====================
test_demo.py::test_demo2
  E:\demo\test_demo.py:13: SyntaxWarning: warning，used to test...
    warnings.warn(SyntaxWarning("warning，used to test..."))

-- Docs: https://docs.pytest.org/en/stable/how-to/capture-warnings.html
================= short test summary info =================
FAILED test_demo.py::test_demo1 - SyntaxWarning: warning，used to test...
========= 1 failed, 1 passed, 1 warning in 0.07s ==========

(demo-HCIhX0Hq) E:\demo>

```

不积跬步，无以至千里

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