package/python-flask-expects-json: new package

This commit adds a new package called python-flask-expects-json, which
also to validate the JSON blurbs submitted to a Flask web
application. A runtime test is added as well, making sure that the
package minimally works with an example Flask application.

The files added by this commit are associated both to Nicolas Carrier
and myself in the DEVELOPERS file, as Nicolas is also interested in
this package.

Signed-off-by: Thomas Petazzoni <thomas.petazzoni@bootlin.com>
Signed-off-by: Arnout Vandecappelle (Essensium/Mind) <arnout@mind.be>

support/testing/tests/package/sample_python_flask_expects_json.py

@@ -0,0 +1,18 @@
+from flask import Flask
+from flask_expects_json import expects_json
+app = Flask(__name__)
+
+schema = {
+    'type': 'object',
+    'properties': {
+        'name': {'type': 'string'},
+        'email': {'type': 'string'},
+    },
+    'required': ['name', 'email']
+}
+
+
+@app.route('/', methods=['POST'])
+@expects_json(schema)
+def hello_world():
+    return 'Hello, World!'

support/testing/tests/package/test_python_flask_expects_json.py

@@ -0,0 +1,38 @@
+from tests.package.test_python import TestPythonPackageBase
+import os
+import time
+
+
+class TestPythonPy3FlaskExpectsJson(TestPythonPackageBase):
+    __test__ = True
+    config = TestPythonPackageBase.config + \
+        """
+        BR2_PACKAGE_LIBCURL=y
+        BR2_PACKAGE_LIBCURL_CURL=y
+        BR2_PACKAGE_PYTHON3=y
+        BR2_PACKAGE_PYTHON_FLASK=y
+        BR2_PACKAGE_PYTHON_FLASK_EXPECTS_JSON=y
+        """
+    sample_scripts = ["tests/package/sample_python_flask_expects_json.py"]
+    timeout = 60
+
+    def try_json(self, payload, expects):
+        cmd = """curl -s -o /dev/null -w "%%{http_code}\\n" -X POST """
+        cmd += """-H "Content-Type: application/json" -d '%s' http://127.0.0.1:5000""" % payload
+        output, exit_code = self.emulator.run(cmd, timeout=self.timeout)
+        self.assertEqual(exit_code, 0)
+        self.assertEqual(output[-1], str(expects))
+
+    def test_run(self):
+        self.login()
+        self.check_sample_scripts_exist()
+        cmd = "FLASK_APP=%s %s -m flask run > /dev/null 2>&1 &" % (os.path.basename(self.sample_scripts[0]),
+                                                                   self.interpreter)
+        _, exit_code = self.emulator.run(cmd, timeout=self.timeout)
+
+        # Give enough time for the flask server to start up
+        time.sleep(15)
+
+        self.try_json("""{"email": "test", "name": "test"}""", 200)
+        self.try_json("""{"email": "test", "name": 2}""", 400)
+        self.try_json("""{"email": "test"}""", 400)