Add integration test for app in module

The example in testdata has a Procfile to show how the service can be started
when the procfile buildpack gets involved. It is currently not used as part of
the testing of this buildpack and provided for documentation purpose.

integration/default_test.go

@@ -125,6 +125,46 @@ func testDefault(t *testing.T, context spec.G, it spec.S) {
 			)
 		})
 
+		it("builds an oci image with site-packages and module", func() {
+			var err error
+			source, err = occam.Source(filepath.Join("testdata", "module_app"))
+			Expect(err).NotTo(HaveOccurred())
+
+			var logs fmt.Stringer
+			image, logs, err = pack.WithNoColor().Build.
+				WithPullPolicy("never").
+				WithBuildpacks(
+					cpythonBuildpack,
+					pipBuildpack,
+					pipInstallBuildpack,
+					buildpack,
+				).
+				Execute(name, source)
+			Expect(err).NotTo(HaveOccurred(), logs.String())
+
+			Expect(logs).To(ContainLines(
+				MatchRegexp(fmt.Sprintf(`%s \d+\.\d+\.\d+`, buildpackInfo.Buildpack.Name)),
+				"  Assigning launch processes:",
+				"    web (default): python",
+			))
+
+			container, err = docker.Container.Run.
+				WithTTY().
+				Execute(image.ID)
+			Expect(err).NotTo(HaveOccurred())
+
+			Eventually(func() string {
+				cLogs, err := docker.Container.Logs.Execute(container.ID)
+				Expect(err).NotTo(HaveOccurred())
+				return cLogs.String()
+			}).Should(
+				And(
+					MatchRegexp(`Python 3\.\d+\.\d+`),
+					ContainSubstring(`Type "help", "copyright", "credits" or "license" for more information.`),
+				),
+			)
+		})
+
 		it("builds an oci image with conda-environment", func() {
 			var err error
 			source, err = occam.Source(filepath.Join("testdata", "conda_app"))

integration/testdata/module_app/Procfile

@@ -0,0 +1 @@
+web: gunicorn module.server:run

integration/testdata/module_app/module/server.py

@@ -0,0 +1,12 @@
+from flask import Flask
+app = Flask(__name__)
+
+@app.route('/')
+def hello_world():
+    return 'Hello, World!'
+
+def run():
+    app.run()
+
+if __name__ == "__main__":
+    run()

integration/testdata/module_app/requirements.txt

@@ -0,0 +1,5 @@
+Flask==2.2.2
+Jinja2==3.1.2
+MarkupSafe==2.1.1
+Werkzeug==2.2.2
+gunicorn==20.1.0