Python: build and deploy legacy parliament functions (deprecated)

cmd/legacy_parliament_test.go

@@ -0,0 +1,85 @@
+package cmd
+
+// LEGACY PYTHON: func-run host rejection test.
+
+import (
+	"errors"
+	"os"
+	"path/filepath"
+	"testing"
+
+	fn "knative.dev/func/pkg/functions"
+	"knative.dev/func/pkg/mock"
+	"knative.dev/func/pkg/oci"
+	. "knative.dev/func/pkg/testing"
+)
+
+// TestRun_LegacyParliamentHostRejected verifies `func run --builder=host` on a
+// legacy parliament function is rejected up front, before any build or run.
+func TestRun_LegacyParliamentHostRejected(t *testing.T) {
+	root := FromTempDirectory(t)
+	if _, err := fn.New().Init(fn.Function{Root: root, Runtime: "python"}); err != nil {
+		t.Fatal(err)
+	}
+	if err := os.WriteFile(filepath.Join(root, "Procfile"), []byte("web: python -m parliament .\n"), 0644); err != nil {
+		t.Fatal(err)
+	}
+
+	builder := mock.NewBuilder()
+	runner := mock.NewRunner()
+	cmd := NewRunCmd(NewTestClient(
+		fn.WithBuilder(builder),
+		fn.WithRunner(runner),
+		fn.WithRegistry("ghcr.com/reg"),
+	))
+	cmd.SetArgs([]string{"--builder=host"})
+
+	_, err := cmd.ExecuteContextC(t.Context())
+	if !errors.Is(err, oci.ErrLegacyParliamentHost) {
+		t.Fatalf("expected ErrLegacyParliamentHost, got %v", err)
+	}
+	if builder.BuildInvoked {
+		t.Error("build should not run for a rejected legacy parliament host run")
+	}
+	if runner.RunInvoked {
+		t.Error("run should not run for a rejected legacy parliament host run")
+	}
+}
+
+// TestRun_UnsupportedLegacyPythonHostRejected verifies `func run --builder=host`
+// on a pre-v1.18 non-parliament Procfile layout (old flask/wsgi templates) is
+// rejected up front with the migration error.
+func TestRun_UnsupportedLegacyPythonHostRejected(t *testing.T) {
+	root := FromTempDirectory(t)
+	if _, err := fn.New().Init(fn.Function{Root: root, Runtime: "python"}); err != nil {
+		t.Fatal(err)
+	}
+	// turn the modern scaffold into the old flask/wsgi shape: a gunicorn
+	// Procfile at root, no root pyproject.toml.
+	if err := os.Remove(filepath.Join(root, "pyproject.toml")); err != nil {
+		t.Fatal(err)
+	}
+	if err := os.WriteFile(filepath.Join(root, "Procfile"), []byte("web: gunicorn func:main --bind=0.0.0.0:8080\n"), 0644); err != nil {
+		t.Fatal(err)
+	}
+
+	builder := mock.NewBuilder()
+	runner := mock.NewRunner()
+	cmd := NewRunCmd(NewTestClient(
+		fn.WithBuilder(builder),
+		fn.WithRunner(runner),
+		fn.WithRegistry("ghcr.com/reg"),
+	))
+	cmd.SetArgs([]string{"--builder=host"})
+
+	_, err := cmd.ExecuteContextC(t.Context())
+	if !errors.Is(err, fn.ErrUnsupportedLegacyPython) {
+		t.Fatalf("expected ErrUnsupportedLegacyPython, got %v", err)
+	}
+	if builder.BuildInvoked {
+		t.Error("build should not run for a rejected legacy python host run")
+	}
+	if runner.RunInvoked {
+		t.Error("run should not run for a rejected legacy python host run")
+	}
+}

cmd/run.go

@@ -175,6 +175,15 @@ func runRun(cmd *cobra.Command, newClient ClientFactory) (err error) {
 
 	container := f.Build.Builder != "host"
 
+	// LEGACY PYTHON: host runner can't run old parliament functions — reject.
+	if !container && f.IsLegacyParliament() {
+		return oci.ErrLegacyParliamentHost
+	}
+	// LEGACY PYTHON: other pre-v1.18 Procfile-based python layouts are rejected too.
+	if !container && f.IsUnsupportedLegacyPython() {
+		return fn.ErrUnsupportedLegacyPython
+	}
+
 	// Ignore the verbose flag if JSON output
 	if cfg.JSON {
 		cfg.Verbose = false

docs/function-templates/python.md

@@ -377,3 +377,26 @@ func deploy --builder=host --registry docker.io/myuser
 
 
 For all deploy options, see `func deploy --help`
+
+## Legacy parliament functions (deprecated)
+
+Before func v1.18, Python functions used the "parliament" style: a bare `func.py`
+exposing `def main(context)`, a `requirements.txt` depending on
+`parliament-functions`, and a `Procfile` (`web: python -m parliament .`).
+
+These functions still build and deploy with the `pack` and `s2i` builders, locally
+and remotely. func builds them the pre-v1.18 way, from the function's own `Procfile`
+and `requirements.txt`, pinning `cloudevents` below 2.0 during the build (the
+parliament stack requires the 1.x line; with the `pack` builder the pin is written
+to a `constraints.txt` file at the function root). The `host` builder does not
+support them. This support is deprecated and will be removed in a future release;
+every build prints a deprecation warning.
+
+The other pre-v1.18 Procfile-based layouts (the old `flask` and `wsgi` templates)
+are not supported and are rejected with an error.
+
+To migrate, recreate the function with the current layout (`func create -l python`)
+and move your logic into the `function` package: `def main(context)` becomes the
+ASGI `handle` (or an instanced `new()`) described above, where the Flask request
+object is replaced by the `scope`/`receive`/`send` interface. Functions that work
+with CloudEvents must also adopt the cloudevents 2.x API.

e2e/e2e_core_test.go

@@ -417,6 +417,77 @@ func TestCore_StaticSignature_Python(t *testing.T) {
 	}
 }
 
+// LEGACY PYTHON: old parliament functions (func.py def main(context) + parliament
+// Procfile) must build and serve via pack and s2i, built locally and in-cluster.
+func TestCore_LegacyParliamentSignature_Python(t *testing.T) {
+	// The fixtures in testdata/legacy-parliament were generated with func
+	// v1.17.0 (the last parliament-era release):
+	//
+	//	func create -l python -t http parliament-http
+	//	func create -l python -t cloudevents parliament-cloudevents
+	//
+	// The cells pair builders, flavors and localities so that each builder
+	// builds both locally and remotely (in-cluster, where scaffolding runs
+	// inside the Tekton pipeline) and each flavor passes through both builders.
+	for _, tc := range []struct {
+		builder  string
+		template string
+		remote   bool
+	}{
+		{"pack", "http", false},
+		{"s2i", "cloudevents", false},
+		{"pack", "cloudevents", true},
+		{"s2i", "http", true},
+	} {
+		cell := tc.builder
+		if tc.remote {
+			cell += "-remote"
+		}
+		t.Run(cell, func(t *testing.T) {
+			name := "func-e2e-parliament-" + cell
+			root := fromCleanEnv(t, name)
+
+			// Copy in the v1.17.0-generated fixture, renaming it for this run;
+			// the rest of the era func.yaml stays as generated.
+			fixture := "parliament-" + tc.template
+			if err := os.CopyFS(root, os.DirFS(filepath.Join(Testdata, "legacy-parliament", fixture))); err != nil {
+				t.Fatal(err)
+			}
+			yamlPath := filepath.Join(root, "func.yaml")
+			y, err := os.ReadFile(yamlPath)
+			if err != nil {
+				t.Fatal(err)
+			}
+			y = bytes.Replace(y, []byte("name: "+fixture), []byte("name: "+name), 1)
+			if err := os.WriteFile(yamlPath, y, 0644); err != nil {
+				t.Fatal(err)
+			}
+
+			args := []string{"deploy", "--builder", tc.builder}
+			if tc.remote {
+				args = append(args, "--remote")
+			}
+			if err := newCmd(t, args...).Run(); err != nil {
+				t.Fatal(err)
+			}
+			defer func() {
+				clean(t, name, Namespace)
+			}()
+
+			if tc.template == "cloudevents" {
+				if !waitFor(t, ksvcUrl(name), withTemplate("cloudevents")) {
+					t.Fatalf("legacy parliament cloudevents function did not deploy correctly with %s builder", tc.builder)
+				}
+			} else {
+				// The parliament http template echoes the query as JSON.
+				if !waitFor(t, ksvcUrl(name)+"?foo=bar", withContentMatch(`{"foo": "bar"}`)) {
+					t.Fatalf("legacy parliament http function did not deploy correctly with %s builder", tc.builder)
+				}
+			}
+		})
+	}
+}
+
 // TestCore_Delete ensures that a function registered as deleted when deleted.
 // Also tests list as a side-effect.
 //

e2e/testdata/legacy-parliament/parliament-cloudevents/.funcignore

@@ -0,0 +1,5 @@
+
+# Use the .funcignore file to exclude files which should not be
+# tracked in the image build. To instruct the system not to track
+# files in the image build, add the regex pattern or file information
+# to this file.

e2e/testdata/legacy-parliament/parliament-cloudevents/Procfile

@@ -0,0 +1 @@
+web: python -m parliament .

e2e/testdata/legacy-parliament/parliament-cloudevents/README.md

@@ -0,0 +1,29 @@
+# Python CloudEvents Function
+
+Welcome to your new Python function project! The boilerplate function
+code can be found in [`func.py`](./func.py). This function is meant
+to respond to [Cloud Events](https://cloudevents.io/).
+
+## Endpoints
+
+Running this function will expose three endpoints.
+
+  * `/` The endpoint for your function.
+  * `/health/readiness` The endpoint for a readiness health check
+  * `/health/liveness` The endpoint for a liveness health check
+
+The health checks can be accessed in your browser at
+[http://localhost:8080/health/readiness]() and
+[http://localhost:8080/health/liveness]().
+
+You can use `func invoke` to send an event to the function endpoint.
+
+
+## Testing
+
+This function project includes a [unit test](./test_func.py). Update this
+as you add business logic to your function in order to test its behavior.
+
+```console
+python test_func.py
+```

e2e/testdata/legacy-parliament/parliament-cloudevents/app.sh

@@ -0,0 +1,3 @@
+#!/bin/sh
+
+exec python -m parliament "$(dirname "$0")"

e2e/testdata/legacy-parliament/parliament-cloudevents/func.py

@@ -0,0 +1,16 @@
+from parliament import Context, event
+
+
+@event
+def main(context: Context):
+    """
+    Function template
+    The context parameter contains the Flask request object and any
+    CloudEvent received with the request.
+    """
+
+    # Add your business logic here
+
+    # The return value here will be applied as the data attribute
+    # of a CloudEvent returned to the function invoker
+    return context.cloud_event.data

e2e/testdata/legacy-parliament/parliament-cloudevents/func.yaml

@@ -0,0 +1,5 @@
+specVersion: 0.36.0
+name: parliament-cloudevents
+runtime: python
+created: 2026-07-02T14:07:38.971733295+02:00
+invoke: cloudevent

e2e/testdata/legacy-parliament/parliament-cloudevents/requirements.txt

@@ -0,0 +1 @@
+parliament-functions==0.1.0

e2e/testdata/legacy-parliament/parliament-cloudevents/test_func.py

@@ -0,0 +1,26 @@
+from cloudevents.http import CloudEvent
+from parliament import Context
+
+import unittest
+
+func = __import__("func")
+
+class TestFunc(unittest.TestCase):
+
+  def test_func(self):
+    # Create a CloudEvent
+    # - The CloudEvent "id" is generated if omitted. "specversion" defaults to "1.0".
+    attributes = {
+        "type": "dev.knative.function",
+        "source": "https://knative.dev/python.event",
+    }
+    data = {"message": "Hello World!"}
+    event = CloudEvent(attributes, data)
+    context = Context(req=None)
+    context.cloud_event = event
+
+    body = func.main(context)
+    self.assertEqual(body.data,  event.data)
+
+if __name__ == "__main__":
+  unittest.main()

e2e/testdata/legacy-parliament/parliament-http/.funcignore

@@ -0,0 +1,5 @@
+
+# Use the .funcignore file to exclude files which should not be
+# tracked in the image build. To instruct the system not to track
+# files in the image build, add the regex pattern or file information
+# to this file.

e2e/testdata/legacy-parliament/parliament-http/Procfile

@@ -0,0 +1 @@
+web: python -m parliament .

e2e/testdata/legacy-parliament/parliament-http/README.md

@@ -0,0 +1,29 @@
+# Python HTTP Function
+
+Welcome to your new Python function project! The boilerplate function
+code can be found in [`func.py`](./func.py). This function will respond
+to incoming HTTP GET and POST requests.
+
+## Endpoints
+
+Running this function will expose three endpoints.
+
+  * `/` The endpoint for your function.
+  * `/health/readiness` The endpoint for a readiness health check
+  * `/health/liveness` The endpoint for a liveness health check
+
+The health checks can be accessed in your browser at
+[http://localhost:8080/health/readiness]() and
+[http://localhost:8080/health/liveness]().
+
+You can use `func invoke` to send an HTTP request to the function endpoint.
+
+
+## Testing
+
+This function project includes a [unit test](./test_func.py). Update this
+as you add business logic to your function in order to test its behavior.
+
+```console
+python test_func.py
+```

e2e/testdata/legacy-parliament/parliament-http/app.sh

@@ -0,0 +1,3 @@
+#!/bin/sh
+
+exec python -m parliament "$(dirname "$0")"