fix(render): do not overwrite function docker network if set, start crossplane-container in same network

cmd/crossplane/render/annotation.go

@@ -0,0 +1,24 @@
+package render
+
+import "strings"
+
+// Annotations is a type used to store annotations.
+type Annotations map[string]string
+
+// NewAnnotationsFromStrings parses an array of strings in the format "key=value" into a map.
+// Silently skips strings in incorrect format.
+func NewAnnotationsFromStrings(annotations []string) Annotations {
+	result := make(Annotations, 0)
+	for _, annotation := range annotations {
+		parts := strings.SplitN(annotation, "=", 2)
+
+		if len(parts) != 2 {
+			continue
+		}
+
+		key, value := parts[0], parts[1]
+		result[key] = value
+	}
+
+	return result
+}

cmd/crossplane/render/engine.go

@@ -58,9 +58,10 @@ type Engine interface {
 // EngineFlags contains flags for configuring the render engine. It is embedded
 // by render command structs to provide shared engine configuration.
 type EngineFlags struct {
-	CrossplaneVersion string `help:"Version of the Crossplane image to use for rendering. Defaults to the latest stable version." placeholder:"VERSION" xor:"crossplane-selector"`
-	CrossplaneImage   string `help:"Override the full Crossplane Docker image reference for rendering."                           placeholder:"IMAGE"   xor:"crossplane-selector"`
-	CrossplaneBinary  string `help:"Path to a local crossplane binary to use instead of Docker."                                  placeholder:"PATH"    type:"existingfile"       xor:"crossplane-selector"`
+	CrossplaneVersion       string `help:"Version of the Crossplane image to use for rendering. Defaults to the latest stable version." placeholder:"VERSION"   xor:"crossplane-selector"`
+	CrossplaneImage         string `help:"Override the full Crossplane Docker image reference for rendering."                           placeholder:"IMAGE"     xor:"crossplane-selector"`
+	CrossplaneBinary        string `help:"Path to a local crossplane binary to use instead of Docker."                                  placeholder:"PATH"      type:"existingfile"       xor:"crossplane-selector,crossplane-docker"`
+	CrossplaneDockerNetwork string `help:"The docker network to start the crossplane container in"                                      xor:"crossplane-docker"`
 }
 
 // NewEngineFromFlags creates an Engine from the flag configuration. If a binary
@@ -71,7 +72,7 @@ func NewEngineFromFlags(f *EngineFlags, log logging.Logger) Engine {
 		return &localRenderEngine{BinaryPath: f.CrossplaneBinary}
 	}
 
-	return &dockerRenderEngine{image: crossplaneImageFromFlags(f), log: log}
+	return &dockerRenderEngine{image: crossplaneImageFromFlags(f), network: f.CrossplaneDockerNetwork, log: log}
 }
 
 func crossplaneImageFromFlags(f *EngineFlags) string {

cmd/crossplane/render/engine_docker.go

@@ -53,8 +53,7 @@ func (realContainerRunner) Run(ctx context.Context, img string, opts ...docker.R
 type dockerRenderEngine struct {
 	// image is the Crossplane Docker image reference.
 	image string
-	// network is the Docker network to connect the container to. When set,
-	// the container joins this network so it can reach function containers.
+	// network is the Docker network to connect the container to.
 	network string
 
 	log logging.Logger
@@ -83,12 +82,20 @@ func (e *dockerRenderEngine) CheckContextSupport() error {
 // containers also join it. The returned cleanup function removes the
 // network.
 func (e *dockerRenderEngine) Setup(ctx context.Context, fns []pkgv1.Function) (func(), error) {
-	networkID, networkName, err := createRenderNetwork(ctx)
+	var networkID, networkName string
+
+	if e.network != "" {
+		// e.network was pre-configured, we don't own the network, so there is nothing to clean up.
+		return func() {}, nil
+	}
+
+	var err error
+	networkID, networkName, err = createRenderNetwork(ctx)
 	if err != nil {
 		return func() {}, errors.Wrap(err, "cannot create Docker network for rendering")
 	}
-
 	e.network = networkName
+
 	injectNetworkAnnotation(fns, networkName)
 
 	cleanup := func() { //nolint:contextcheck // Detached context for cleanup.

cmd/crossplane/render/op/cmd.go

@@ -167,6 +167,24 @@ func (c *Cmd) Run(k *kong.Context, log logging.Logger, sp terminal.SpinnerPrinte
 		}
 	}
 
+	if c.CrossplaneDockerNetwork == "" {
+		// Default to the first docker-network annotation in the provided functions
+		for _, fn := range fns {
+			if value, ok := fn.Annotations[render.AnnotationKeyRuntimeDockerNetwork]; ok {
+				c.CrossplaneDockerNetwork = value
+				break
+			}
+		}
+
+		// Overwrite with docker-network annotation from function-annotations cli flag if set
+		if len(c.FunctionAnnotations) > 0 {
+			annotations := render.NewAnnotationsFromStrings(c.FunctionAnnotations)
+			if value, ok := annotations[render.AnnotationKeyRuntimeDockerNetwork]; ok {
+				c.CrossplaneDockerNetwork = value
+			}
+		}
+	}
+
 	engine := c.newEngine(&c.EngineFlags, log)
 
 	seedCtx := len(c.ContextValues) > 0 || len(c.ContextFiles) > 0

cmd/crossplane/render/render.go

@@ -151,14 +151,19 @@ func RewriteAddressesForDocker(fns []*renderv1alpha1.FunctionInput) []*renderv1a
 	return fns
 }
 
-// injectNetworkAnnotation sets the Docker network annotation on all functions
+// injectNetworkAnnotation sets the Docker network annotation
+// on all functions without existing runtime-docker-network annotation
 // so their containers join the specified network.
 func injectNetworkAnnotation(fns []pkgv1.Function, networkName string) {
 	for i := range fns {
 		if fns[i].Annotations == nil {
 			fns[i].Annotations = make(map[string]string)
 		}
-		fns[i].Annotations[AnnotationKeyRuntimeDockerNetwork] = networkName
+
+		_, ok := fns[i].Annotations[AnnotationKeyRuntimeDockerNetwork]
+		if !ok {
+			fns[i].Annotations[AnnotationKeyRuntimeDockerNetwork] = networkName
+		}
 	}
 }
 

cmd/crossplane/render/xr/cmd.go

@@ -224,6 +224,24 @@ func (c *Cmd) Run(k *kong.Context, log logging.Logger, sp terminal.SpinnerPrinte
 		}
 	}
 
+	if c.CrossplaneDockerNetwork == "" {
+		// Default to the first docker-network annotation in the provided functions
+		for _, fn := range fns {
+			if value, ok := fn.Annotations[render.AnnotationKeyRuntimeDockerNetwork]; ok {
+				c.CrossplaneDockerNetwork = value
+				break
+			}
+		}
+
+		// Overwrite with docker-network annotation from function-annotations cli flag if set
+		if len(c.FunctionAnnotations) > 0 {
+			annotations := render.NewAnnotationsFromStrings(c.FunctionAnnotations)
+			if value, ok := annotations[render.AnnotationKeyRuntimeDockerNetwork]; ok {
+				c.CrossplaneDockerNetwork = value
+			}
+		}
+	}
+
 	engine := c.newEngine(&c.EngineFlags, log)
 
 	seedCtx := len(c.ContextValues) > 0 || len(c.ContextFiles) > 0