Run linters and formatters via pre-commit

.circleci/config.yml

@@ -62,7 +62,7 @@ jobs:
       - checkout
       - run: pip install tox
       - run: tox
-   
+
 
 workflows:
   version: 2

.coveragerc

@@ -11,4 +11,4 @@ source =
    .tox/pypy/site-packages/prometheus_client
 
 [report]
-show_missing = True
+show_missing = True

.gitignore

@@ -7,4 +7,4 @@ dist
 .coverage
 .tox
 .*cache
-htmlcov
+htmlcov

.pre-commit-config.yaml

@@ -0,0 +1,26 @@
+# See https://pre-commit.com for more information
+# See https://pre-commit.com/hooks.html for more hooks
+repos:
+  - repo: https://github.com/pre-commit/pre-commit-hooks
+    rev: v4.2.0
+    hooks:
+      - id: check-added-large-files
+      - id: check-ast
+      - id: check-builtin-literals
+      - id: check-case-conflict
+      - id: check-docstring-first
+      - id: check-merge-conflict
+      - id: check-toml
+      - id: check-yaml
+      - id: debug-statements
+      - id: end-of-file-fixer
+  - repo: https://github.com/pycqa/flake8
+    rev: 4.0.1
+    hooks:
+      - id: flake8
+        additional_dependencies:
+          - 'flake8-docstrings==1.5.0'
+  - repo: https://github.com/pycqa/isort
+    rev: 5.10.1
+    hooks:
+      - id: isort

CONTRIBUTING.md

@@ -19,24 +19,25 @@ Prometheus uses GitHub to manage reviews of pull requests.
 Submitted changes should pass the current tests, and be covered by new test
 cases when adding functionality.
 
+* [Install `pre-commit`](https://pre-commit.com/index.html#installation)
+  and run `pre-commit install` in the repository.
+
 * Run the tests locally using [tox] which executes the full suite on all
   supported Python versions installed.
 
-* Each pull request is gated using [Travis CI] with the results linked on the
-  github page. This must pass before the change can land, note pushing a new
+* Each pull request is gated using [CircleCI] with the results linked on the
+  GitHub page. This must pass before the change can land, note pushing a new
   change will trigger a retest.
 
 ## Style
 
 * Code style should follow [PEP 8] generally, and can be checked by running:
-  ``tox -e flake8``.
-
-* Import statements can be automatically formatted using [isort].
+  `pre-commit run`.
 
 
 [our mailing list]: https://groups.google.com/forum/?fromgroups#!forum/prometheus-developers
 [Developer Certificate of Origin]: https://github.com/prometheus/prometheus/wiki/DCO-signing
 [isort]: https://pypi.org/project/isort/
 [PEP 8]: https://www.python.org/dev/peps/pep-0008/
 [tox]: https://tox.readthedocs.io/en/latest/
-[Travis CI]: https://docs.travis-ci.com/
+[CircleCI]: https://circleci.com/

README.md

@@ -274,8 +274,8 @@ ProcessCollector(namespace='mydaemon', pid=lambda: open('/var/run/daemon.pid').r
 ### Platform Collector
 
 The client also automatically exports some metadata about Python. If using Jython,
-metadata about the JVM in use is also included. This information is available as 
-labels on the `python_info` metric. The value of the metric is 1, since it is the 
+metadata about the JVM in use is also included. This information is available as
+labels on the `python_info` metric. The value of the metric is 1, since it is the
 labels that carry information.
 
 ## Exporting
@@ -367,7 +367,7 @@ Such an application can be useful when integrating Prometheus metrics with ASGI
 apps.
 
 By default, the WSGI application will respect `Accept-Encoding:gzip` headers used by Prometheus
-and compress the response if such a header is present. This behaviour can be disabled by passing 
+and compress the response if such a header is present. This behaviour can be disabled by passing
 `disable_compression=True` when creating the app, like this:
 
 ```python

prometheus_client/exposition.py

@@ -34,8 +34,9 @@
     'write_to_textfile',
 )
 
+# Content type of the latest text format
 CONTENT_TYPE_LATEST = 'text/plain; version=0.0.4; charset=utf-8'
-"""Content type of the latest text format"""
+
 PYTHON376_OR_NEWER = sys.version_info > (3, 7, 5)
 
 

prometheus_client/gc_collector.py

@@ -41,5 +41,5 @@ def collect(self) -> Iterable[Metric]:
         return [collected, uncollectable, collections]
 
 
+# Default GCCollector in default Registry REGISTRY.
 GC_COLLECTOR = GCCollector()
-"""Default GCCollector in default Registry REGISTRY."""

prometheus_client/openmetrics/exposition.py

@@ -3,8 +3,8 @@
 
 from ..utils import floatToGoString
 
+# Content type of the latest OpenMetrics text format
 CONTENT_TYPE_LATEST = 'application/openmetrics-text; version=0.0.1; charset=utf-8'
-"""Content type of the latest OpenMetrics text format"""
 
 
 def _is_valid_exemplar_metric(metric, sample):

prometheus_client/openmetrics/parser.py

@@ -196,7 +196,7 @@ def _parse_labels(text):
             label_name = sub_labels[:value_start]
             sub_labels = sub_labels[value_start + 1:]
 
-            # Check for missing quotes 
+            # Check for missing quotes
             if not sub_labels or sub_labels[0] != '"':
                 raise ValueError
 
@@ -240,7 +240,7 @@ def _parse_labels(text):
             # Check for missing commas
             if sub_labels and next_comma == 0:
                 raise ValueError
-            
+
         return labels
 
     except ValueError:
@@ -283,7 +283,7 @@ def _parse_remaining_text(text):
     val = _parse_value(split_text[0])
     if len(split_text) == 1:
         # We don't have timestamp or exemplar
-        return val, None, None  
+        return val, None, None
 
     timestamp = []
     exemplar_value = []

prometheus_client/platform_collector.py

@@ -55,5 +55,5 @@ def _java(self):
         }
 
 
+# PlatformCollector in default Registry REGISTRY
 PLATFORM_COLLECTOR = PlatformCollector()
-"""PlatformCollector in default Registry REGISTRY"""

prometheus_client/process_collector.py

@@ -97,5 +97,5 @@ def collect(self) -> Iterable[Metric]:
         return result
 
 
+# Default ProcessCollector in default Registry REGISTRY.
 PROCESS_COLLECTOR = ProcessCollector()
-"""Default ProcessCollector in default Registry REGISTRY."""

tests/test_asgi.py

@@ -48,7 +48,7 @@ def tearDown(self):
             asyncio.get_event_loop().run_until_complete(
                 self.communicator.wait()
             )
-            
+
     def seed_app(self, app):
         self.communicator = ApplicationCommunicator(app, self.scope)