common/pkg/json-proxy: extract proxy library from skopeo

.cirrus.yml

@@ -287,6 +287,7 @@
       make build
       make build-cross
       make test
+      make test-integration
 
 storage_cross_task:
     only_if: *only_if_storage
@@ -317,7 +318,7 @@
 # Status aggregator for all tests.  This task simply ensures a defined
 # set of tasks all passed, and allows confirming that based on the status
 # of this task.
 success_task:
     alias: success
     # N/B: The prow merge-bot (tide) is sensitized to this exact name, DO NOT CHANGE IT.
     # Ref: https://github.com/openshift/release/pull/49820

common/Makefile

@@ -103,6 +103,14 @@ test-unit: netavark-testplugin
 	go test --tags seccomp,$(BUILDTAGS) -v ./...
 	go test --tags remote,$(BUILDTAGS) -v ./pkg/config
 
+.PHONY: bin/json-proxy-test-server
+bin/json-proxy-test-server:
+	$(GO_BUILD) -o $@ ./cmd/json-proxy-test-server/
+
+.PHONY: test-integration
+test-integration: bin/json-proxy-test-server
+	JSON_PROXY_TEST_BINARY=$(CURDIR)/bin/json-proxy-test-server go test --tags $(BUILDTAGS) -v ./pkg/json-proxy/
+
 clean: ## Clean artifacts
 	$(MAKE) -C docs clean
 	find . -name \*~ -delete

common/cmd/json-proxy-test-server/main.go

@@ -0,0 +1,49 @@
+//go:build !windows
+
+package main
+
+import (
+	"context"
+	"fmt"
+	"os"
+	"strconv"
+
+	"go.podman.io/common/pkg/json-proxy"
+	"go.podman.io/image/v5/signature"
+	"go.podman.io/image/v5/types"
+)
+
+func main() {
+	if err := run(); err != nil {
+		fmt.Fprintf(os.Stderr, "error: %v\n", err)
+		os.Exit(1)
+	}
+}
+
+func run() error {
+	if len(os.Args) < 3 || os.Args[1] != "--sockfd" {
+		return fmt.Errorf("usage: %s --sockfd <fd>", os.Args[0])
+	}
+	sockfd, err := strconv.Atoi(os.Args[2])
+	if err != nil {
+		return fmt.Errorf("invalid sockfd: %v", err)
+	}
+
+	manager, err := jsonproxy.NewManager(
+		jsonproxy.WithSystemContext(func() (*types.SystemContext, error) {
+			return &types.SystemContext{}, nil
+		}),
+		jsonproxy.WithPolicyContext(func() (*signature.PolicyContext, error) {
+			policy, err := signature.DefaultPolicy(nil)
+			if err != nil {
+				return nil, err
+			}
+			return signature.NewPolicyContext(policy)
+		}),
+	)
+	if err != nil {
+		return err
+	}
+	defer manager.Close()
+	return manager.Serve(context.Background(), sockfd)
+}