add go-license

.gitignore

@@ -0,0 +1,3 @@
+venv
+.pytest_cache
+__pycache__

go-license/go.mod

@@ -0,0 +1,3 @@
+module git.rdctd.de/timo/blog/go-license
+
+go 1.23.2

go-license/license.go

@@ -0,0 +1,89 @@
+package golicense
+
+import (
+	"crypto/hmac"
+	"crypto/sha256"
+	"encoding/base64"
+	"encoding/json"
+	"errors"
+	"time"
+)
+
+var (
+	secret            = []byte("superDuperSecret123!")
+	ErrorHmacMismatch = errors.New("checksum mismatch - not a valid license key")
+)
+
+type Data struct {
+	Feature1  bool
+	Feature2  int
+	ValidTill time.Time
+	CreatedAt time.Time
+}
+
+type Envelope struct {
+	Data     Data
+	Checksum []byte
+}
+
+func (e *Envelope) String() (string, error) {
+	d, err := json.Marshal(e)
+	if err != nil {
+		return "", err
+	}
+
+	str := base64.StdEncoding.EncodeToString(d)
+	return str, nil
+}
+
+func New(feature1 bool, feature2 int, expire int) (*Envelope, error) {
+	d := Data{
+		Feature1:  feature1,
+		Feature2:  feature2,
+		ValidTill: time.Now().AddDate(0, 0, expire),
+	}
+
+	e := Envelope{
+		Data: d,
+	}
+
+	db, err := json.Marshal(&d)
+	if err != nil {
+		return nil, err
+	}
+
+	hmac := hmac.New(sha256.New, secret)
+	hmac.Write(db)
+	dh := hmac.Sum(nil)
+
+	e.Checksum = dh
+
+	return &e, nil
+}
+
+func Verify(in string) (*Envelope, error) {
+	d, err := base64.StdEncoding.DecodeString(in)
+	if err != nil {
+		return nil, err
+	}
+
+	var e Envelope
+	if err := json.Unmarshal(d, &e); err != nil {
+		return nil, err
+	}
+
+	db, err := json.Marshal(e.Data)
+	if err != nil {
+		return nil, err
+	}
+
+	hm := hmac.New(sha256.New, secret)
+	hm.Write(db)
+	dh := hm.Sum(nil)
+
+	if !hmac.Equal(e.Checksum, dh) {
+		return nil, ErrorHmacMismatch
+	}
+
+	return &e, nil
+}

go-license/license_test.go

@@ -0,0 +1,57 @@
+package golicense
+
+import (
+	"testing"
+)
+
+func TestVerify(t *testing.T) {
+	e, err := New(true, 5, 365)
+	if err != nil {
+		t.Error(err)
+	}
+
+	key, err := e.String()
+	if err != nil {
+		t.Error(err)
+	}
+
+	e2, err := Verify(key)
+	if err != nil {
+		t.Error(err)
+	}
+
+	if e2.Data.Feature1 != e.Data.Feature1 {
+		t.Error("Feature1 mismatch")
+	}
+
+	if e2.Data.Feature2 != e.Data.Feature2 {
+		t.Error("Feature2 mismatchh")
+	}
+}
+
+func TestVerifyMismatch(t *testing.T) {
+	e1, _ := New(true, 5, 365)
+
+	e2, _ := New(false, 5, 365)
+
+	key1, _ := e1.String()
+	key2, _ := e2.String()
+
+	if key1 == key2 {
+		t.Error("same keys, different license data")
+	}
+}
+
+func TestVerifyModifiedData(t *testing.T) {
+	e, _ := New(false, 5, 365)
+
+	e.Data.Feature1 = true
+
+	key, _ := e.String()
+
+	_, err := Verify(key)
+
+	if err != ErrorHmacMismatch {
+		t.Error("No HmacMismatch error")
+	}
+}

parameterize/Readme.md

@@ -0,0 +1,29 @@
+# pytest parametrize demo
+Use parametrize with Django waffle. See blog post (TBD)
+
+Output
+
+```python
+(venv) timo@dev:~/blog/parametrize$ pytest
+=============================================================================================== test session starts ================================================================================================
+platform linux -- Python 3.9.2, pytest-7.4.4, pluggy-1.4.0
+django: version: 4.2.9, settings: demo.settings (from ini)
+rootdir: /home/timo/blog/parametrize
+configfile: pytest.ini
+plugins: django-4.7.0
+collected 5 items
+
+app/tests.py::test_complex_function[True]
+-------------------------------------------------------------------------------------------------- live log call ---------------------------------------------------------------------------------------------------
+INFO     app_tests:code.py:24 rewrite complex
+PASSED                                                                                                                                                                                                       [ 20%]
+app/tests.py::test_complex_function[False]
+-------------------------------------------------------------------------------------------------- live log call ---------------------------------------------------------------------------------------------------
+INFO     app_tests:code.py:29 deprecated complex
+PASSED                                                                                                                                                                                                       [ 40%]
+app/tests.py::test_simple[foo bar] PASSED                                                                                                                                                                    [ 60%]
+app/tests.py::test_simple[baz zab] PASSED                                                                                                                                                                    [ 80%]
+app/tests.py::test_simple[1 2 3 4 5] PASSED                                                                                                                                                                  [100%]
+
+================================================================================================ 5 passed in 0.21s =================================================================================================
+```

parameterize/app/code.py

@@ -0,0 +1,37 @@
+# coding: utf-8
+import logging
+
+from waffle import switch_is_active
+
+
+logger = logging.getLogger("app_tests")
+
+
+def simple(name: str) -> str:
+    name = name.replace(" ", "-")
+    name = name.lower()
+    return name
+
+
+def complex_function(x: int, y: int) -> int:
+    if switch_is_active("new_complex"):
+        return rewrite_complex_function(x, y)
+
+    return deprecated_complex_function(x, y)
+
+
+def rewrite_complex_function(x: int, y: int) -> int:
+    logger.info("rewrite complex")
+    return x * y
+
+
+def deprecated_complex_function(x: int, y: int) -> int:
+    def foo() -> int:
+        return int(True)
+
+    logger.info("deprecated complex")
+    return x * y * foo()
+
+
+def foo():
+    x = Double(3.4)

parameterize/app/tests.py

@@ -0,0 +1,25 @@
+# coding: utf-8
+import pytest
+from waffle.testutils import override_switch
+
+from app.code import simple, complex_function
+
+
+@pytest.mark.parametrize(
+    "name",
+    (
+        "foo bar",
+        "baz zab",
+        "1 2 3 4 5"
+   )
+)
+def test_simple(name):
+    assert " " not in simple(name)
+
+
+@pytest.mark.parametrize("switch", (True, False))
+@pytest.mark.django_db
+def test_complex_function(switch):
+    with override_switch("new_complex", active=switch):
+        assert complex_function(2, 2) == 4
+

parameterize/demo/asgi.py

@@ -0,0 +1,16 @@
+"""
+ASGI config for demo project.
+
+It exposes the ASGI callable as a module-level variable named ``application``.
+
+For more information on this file, see
+https://docs.djangoproject.com/en/4.2/howto/deployment/asgi/
+"""
+
+import os
+
+from django.core.asgi import get_asgi_application
+
+os.environ.setdefault('DJANGO_SETTINGS_MODULE', 'demo.settings')
+
+application = get_asgi_application()

parameterize/demo/settings.py

@@ -0,0 +1,125 @@
+"""
+Django settings for demo project.
+
+Generated by 'django-admin startproject' using Django 4.2.9.
+
+For more information on this file, see
+https://docs.djangoproject.com/en/4.2/topics/settings/
+
+For the full list of settings and their values, see
+https://docs.djangoproject.com/en/4.2/ref/settings/
+"""
+
+from pathlib import Path
+
+# Build paths inside the project like this: BASE_DIR / 'subdir'.
+BASE_DIR = Path(__file__).resolve().parent.parent
+
+
+# Quick-start development settings - unsuitable for production
+# See https://docs.djangoproject.com/en/4.2/howto/deployment/checklist/
+
+# SECURITY WARNING: keep the secret key used in production secret!
+SECRET_KEY = 'django-insecure-tl0nxteo!j41cj1l8q6bpbn^-b67g83l3)t1g%%t*a(52%qf(w'
+
+# SECURITY WARNING: don't run with debug turned on in production!
+DEBUG = True
+
+ALLOWED_HOSTS = []
+
+
+# Application definition
+
+INSTALLED_APPS = [
+    'django.contrib.admin',
+    'django.contrib.auth',
+    'django.contrib.contenttypes',
+    'django.contrib.sessions',
+    'django.contrib.messages',
+    'django.contrib.staticfiles',
+    "waffle",
+    "app"
+]
+
+MIDDLEWARE = [
+    'django.middleware.security.SecurityMiddleware',
+    'django.contrib.sessions.middleware.SessionMiddleware',
+    'django.middleware.common.CommonMiddleware',
+    'django.middleware.csrf.CsrfViewMiddleware',
+    'django.contrib.auth.middleware.AuthenticationMiddleware',
+    'django.contrib.messages.middleware.MessageMiddleware',
+    'django.middleware.clickjacking.XFrameOptionsMiddleware',
+]
+
+ROOT_URLCONF = 'demo.urls'
+
+TEMPLATES = [
+    {
+        'BACKEND': 'django.template.backends.django.DjangoTemplates',
+        'DIRS': [],
+        'APP_DIRS': True,
+        'OPTIONS': {
+            'context_processors': [
+                'django.template.context_processors.debug',
+                'django.template.context_processors.request',
+                'django.contrib.auth.context_processors.auth',
+                'django.contrib.messages.context_processors.messages',
+            ],
+        },
+    },
+]
+
+WSGI_APPLICATION = 'demo.wsgi.application'
+
+
+# Database
+# https://docs.djangoproject.com/en/4.2/ref/settings/#databases
+
+DATABASES = {
+    'default': {
+        'ENGINE': 'django.db.backends.sqlite3',
+        'NAME': BASE_DIR / 'db.sqlite3',
+    }
+}
+
+
+# Password validation
+# https://docs.djangoproject.com/en/4.2/ref/settings/#auth-password-validators
+
+AUTH_PASSWORD_VALIDATORS = [
+    {
+        'NAME': 'django.contrib.auth.password_validation.UserAttributeSimilarityValidator',
+    },
+    {
+        'NAME': 'django.contrib.auth.password_validation.MinimumLengthValidator',
+    },
+    {
+        'NAME': 'django.contrib.auth.password_validation.CommonPasswordValidator',
+    },
+    {
+        'NAME': 'django.contrib.auth.password_validation.NumericPasswordValidator',
+    },
+]
+
+
+# Internationalization
+# https://docs.djangoproject.com/en/4.2/topics/i18n/
+
+LANGUAGE_CODE = 'en-us'
+
+TIME_ZONE = 'UTC'
+
+USE_I18N = True
+
+USE_TZ = True
+
+
+# Static files (CSS, JavaScript, Images)
+# https://docs.djangoproject.com/en/4.2/howto/static-files/
+
+STATIC_URL = 'static/'
+
+# Default primary key field type
+# https://docs.djangoproject.com/en/4.2/ref/settings/#default-auto-field
+
+DEFAULT_AUTO_FIELD = 'django.db.models.BigAutoField'

parameterize/demo/urls.py

@@ -0,0 +1,22 @@
+"""
+URL configuration for demo project.
+
+The `urlpatterns` list routes URLs to views. For more information please see:
+    https://docs.djangoproject.com/en/4.2/topics/http/urls/
+Examples:
+Function views
+    1. Add an import:  from my_app import views
+    2. Add a URL to urlpatterns:  path('', views.home, name='home')
+Class-based views
+    1. Add an import:  from other_app.views import Home
+    2. Add a URL to urlpatterns:  path('', Home.as_view(), name='home')
+Including another URLconf
+    1. Import the include() function: from django.urls import include, path
+    2. Add a URL to urlpatterns:  path('blog/', include('blog.urls'))
+"""
+from django.contrib import admin
+from django.urls import path
+
+urlpatterns = [
+    path('admin/', admin.site.urls),
+]

parameterize/demo/wsgi.py

@@ -0,0 +1,16 @@
+"""
+WSGI config for demo project.
+
+It exposes the WSGI callable as a module-level variable named ``application``.
+
+For more information on this file, see
+https://docs.djangoproject.com/en/4.2/howto/deployment/wsgi/
+"""
+
+import os
+
+from django.core.wsgi import get_wsgi_application
+
+os.environ.setdefault('DJANGO_SETTINGS_MODULE', 'demo.settings')
+
+application = get_wsgi_application()

parameterize/manage.py

@@ -0,0 +1,22 @@
+#!/usr/bin/env python
+"""Django's command-line utility for administrative tasks."""
+import os
+import sys
+
+
+def main():
+    """Run administrative tasks."""
+    os.environ.setdefault('DJANGO_SETTINGS_MODULE', 'demo.settings')
+    try:
+        from django.core.management import execute_from_command_line
+    except ImportError as exc:
+        raise ImportError(
+            "Couldn't import Django. Are you sure it's installed and "
+            "available on your PYTHONPATH environment variable? Did you "
+            "forget to activate a virtual environment?"
+        ) from exc
+    execute_from_command_line(sys.argv)
+
+
+if __name__ == '__main__':
+    main()

parameterize/pytest.ini

@@ -0,0 +1,6 @@
+[pytest]
+DJANGO_SETTINGS_MODULE=demo.settings
+python_files=tests.py
+addopts = --create-db
+log_cli = True
+log_cli_level = INFO

parameterize/requirements.txt

@@ -0,0 +1,12 @@
+asgiref==3.7.2
+Django==4.2.9
+django-waffle==4.1.0
+exceptiongroup==1.2.0
+iniconfig==2.0.0
+packaging==23.2
+pluggy==1.4.0
+pytest==7.4.4
+pytest-django==4.7.0
+sqlparse==0.4.4
+tomli==2.0.1
+typing-extensions==4.9.0