Add more Topology samples with various architectures

This commit is contained in:
Jean-Gabriel Gill-Couture 2025-03-31 15:02:41 -04:00
parent fda007f014
commit 6e9bf3a4be
4 changed files with 1353 additions and 261 deletions

View File

@ -1,315 +1,232 @@
use rand::Rng;
use std::process::Command;
// Basic traits from your example
trait Topology {}
pub trait Capability {}
pub trait CommandCapability: Capability {
fn execute_command(&self, command: &str, args: &[&str]) -> Result<String, String>;
trait Score: Clone + std::fmt::Debug {
fn get_interpret<T: Topology>(&self) -> Box<dyn Interpret<T>>;
fn name(&self) -> String;
}
pub trait KubernetesCapability: Capability {
fn apply_manifest(&self, manifest: &str) -> Result<(), String>;
fn get_resource(&self, resource_type: &str, name: &str) -> Result<String, String>;
trait Interpret<T: Topology> {
fn execute(&self);
}
pub trait Topology {
fn name(&self) -> &str;
struct Maestro<T: Topology> {
topology: T
}
pub trait Score<T: Topology> {
fn compile(&self) -> Result<Box<dyn Interpret<T>>, String>;
fn name(&self) -> &str;
}
pub struct LinuxHostTopology {
name: String,
host: String,
}
impl Capability for LinuxHostTopology {}
impl LinuxHostTopology {
pub fn new(name: String, host: String) -> Self {
Self { name, host }
impl<T: Topology> Maestro<T> {
pub fn new(topology: T) -> Self {
Maestro { topology }
}
pub fn register_score<S: Score + 'static>(&self, score: S) {
println!("Registering score: {}", score.name());
}
pub fn execute_score<S: Score + 'static>(&self, score: S) {
println!("Executing score: {}", score.name());
score.get_interpret::<T>().execute();
}
}
impl Topology for LinuxHostTopology {
fn name(&self) -> &str {
&self.name
// Capability traits - these are used to enforce requirements
trait CommandExecution {
fn execute_command(&self, command: &[String]) -> Result<String, String>;
}
trait FileSystem {
fn read_file(&self, path: &str) -> Result<String, String>;
fn write_file(&self, path: &str, content: &str) -> Result<(), String>;
}
// A concrete topology implementation
#[derive(Clone, Debug)]
struct LinuxHostTopology {
hostname: String,
}
impl Topology for LinuxHostTopology {}
// Implement the capabilities for LinuxHostTopology
impl CommandExecution for LinuxHostTopology {
fn execute_command(&self, command: &[String]) -> Result<String, String> {
println!("Executing command on {}: {:?}", self.hostname, command);
// In a real implementation, this would use std::process::Command
Ok(format!("Command executed successfully on {}", self.hostname))
}
}
impl CommandCapability for LinuxHostTopology {
fn execute_command(&self, command: &str, args: &[&str]) -> Result<String, String> {
println!("Executing on {}: {} {:?}", self.host, command, args);
// In a real implementation, this would SSH to the host and execute the command
let output = Command::new(command)
.args(args)
.output()
.map_err(|e| e.to_string())?;
if output.status.success() {
Ok(String::from_utf8_lossy(&output.stdout).to_string())
} else {
Err(String::from_utf8_lossy(&output.stderr).to_string())
}
impl FileSystem for LinuxHostTopology {
fn read_file(&self, path: &str) -> Result<String, String> {
println!("Reading file {} on {}", path, self.hostname);
Ok(format!("Content of {} on {}", path, self.hostname))
}
}
pub struct K3DTopology {
name: String,
linux_host: LinuxHostTopology,
cluster_name: String,
}
impl Capability for K3DTopology {}
impl K3DTopology {
pub fn new(name: String, linux_host: LinuxHostTopology, cluster_name: String) -> Self {
Self {
name,
linux_host,
cluster_name,
}
}
}
impl Topology for K3DTopology {
fn name(&self) -> &str {
&self.name
}
}
impl CommandCapability for K3DTopology {
fn execute_command(&self, command: &str, args: &[&str]) -> Result<String, String> {
self.linux_host.execute_command(command, args)
}
}
impl KubernetesCapability for K3DTopology {
fn apply_manifest(&self, manifest: &str) -> Result<(), String> {
println!("Applying manifest to K3D cluster '{}'", self.cluster_name);
// Write manifest to a temporary file
//let temp_file = format!("/tmp/manifest-{}.yaml", rand::thread_rng().gen::<u32>());
let temp_file = format!("/tmp/manifest-TODO_RANDOM_NUMBER.yaml");
// Use the linux_host directly to avoid capability trait bounds
self.linux_host
.execute_command("bash", &["-c", &format!("cat > {}", temp_file)])?;
// Apply with kubectl
self.linux_host.execute_command("kubectl", &[
"--context",
&format!("k3d-{}", self.cluster_name),
"apply",
"-f",
&temp_file,
])?;
fn write_file(&self, path: &str, content: &str) -> Result<(), String> {
println!("Writing to file {} on {}: {}", path, self.hostname, content);
Ok(())
}
}
fn get_resource(&self, resource_type: &str, name: &str) -> Result<String, String> {
println!(
"Getting resource {}/{} from K3D cluster '{}'",
resource_type, name, self.cluster_name
);
self.linux_host.execute_command("kubectl", &[
"--context",
&format!("k3d-{}", self.cluster_name),
"get",
resource_type,
name,
"-o",
"yaml",
])
// Another topology that doesn't support command execution
#[derive(Clone, Debug)]
struct BareMetalTopology {
device_id: String,
}
impl Topology for BareMetalTopology {}
impl FileSystem for BareMetalTopology {
fn read_file(&self, path: &str) -> Result<String, String> {
println!("Reading file {} on device {}", path, self.device_id);
Ok(format!("Content of {} on device {}", path, self.device_id))
}
fn write_file(&self, path: &str, content: &str) -> Result<(), String> {
println!("Writing to file {} on device {}: {}", path, self.device_id, content);
Ok(())
}
}
pub struct CommandScore {
// CommandScore implementation
#[derive(Clone, Debug)]
struct CommandScore {
name: String,
command: String,
args: Vec<String>,
}
impl CommandScore {
pub fn new(name: String, command: String, args: Vec<String>) -> Self {
Self {
name,
command,
args,
pub fn new(name: String, args: Vec<String>) -> Self {
CommandScore { name, args }
}
}
impl Score for CommandScore {
fn get_interpret<T: Topology + CommandExecution + 'static>(&self) -> Box<dyn Interpret<T>> {
// This is the key part: we constrain T to implement CommandExecution
// If T doesn't implement CommandExecution, this will fail to compile
Box::new(CommandInterpret::<T>::new(self.clone()))
}
fn name(&self) -> String {
self.name.clone()
}
}
// CommandInterpret implementation
struct CommandInterpret<T: Topology + CommandExecution> {
score: CommandScore,
_marker: std::marker::PhantomData<T>,
}
impl<T: Topology + CommandExecution> CommandInterpret<T> {
pub fn new(score: CommandScore) -> Self {
CommandInterpret {
score,
_marker: std::marker::PhantomData,
}
}
}
pub trait Interpret<T: Topology> {
fn execute(&self, topology: &T) -> Result<String, String>;
}
struct CommandInterpret;
impl<T> Interpret<T> for CommandInterpret
where
T: Topology + CommandCapability,
{
fn execute(&self, topology: &T) -> Result<String, String> {
todo!()
impl<T: Topology + CommandExecution> Interpret<T> for CommandInterpret<T> {
fn execute(&self) {
println!("Command interpret is executing: {:?}", self.score.args);
// In a real implementation, you would call the topology's execute_command method
// topology.execute_command(&self.score.args);
}
}
impl<T> Score<T> for CommandScore
where
T: Topology + CommandCapability,
{
fn compile(&self) -> Result<Box<dyn Interpret<T>>, String> {
Ok(Box::new(CommandInterpret {}))
}
fn name(&self) -> &str {
&self.name
}
}
#[derive(Clone)]
pub struct K8sResourceScore {
// FileScore implementation - a different type of score that requires FileSystem capability
#[derive(Clone, Debug)]
struct FileScore {
name: String,
manifest: String,
path: String,
content: Option<String>,
}
impl K8sResourceScore {
pub fn new(name: String, manifest: String) -> Self {
Self { name, manifest }
impl FileScore {
pub fn new_read(name: String, path: String) -> Self {
FileScore { name, path, content: None }
}
pub fn new_write(name: String, path: String, content: String) -> Self {
FileScore { name, path, content: Some(content) }
}
}
struct K8sResourceInterpret {
score: K8sResourceScore,
}
impl<T: Topology + KubernetesCapability> Interpret<T> for K8sResourceInterpret {
fn execute(&self, topology: &T) -> Result<String, String> {
todo!()
impl Score for FileScore {
fn get_interpret<T: Topology>(&self) -> Box<dyn Interpret<T>> {
// This constrains T to implement FileSystem
Box::new(FileInterpret::<T>::new(self.clone()))
}
fn name(&self) -> String {
self.name.clone()
}
}
impl<T> Score<T> for K8sResourceScore
where
T: Topology + KubernetesCapability,
{
fn compile(&self) -> Result<Box<(dyn Interpret<T> + 'static)>, String> {
Ok(Box::new(K8sResourceInterpret {
score: self.clone(),
}))
}
fn name(&self) -> &str {
&self.name
}
// FileInterpret implementation
struct FileInterpret<T: Topology + FileSystem> {
score: FileScore,
_marker: std::marker::PhantomData<T>,
}
pub struct Maestro<T: Topology> {
topology: T,
scores: Vec<Box<dyn Score<T>>>,
}
impl<T: Topology> Maestro<T> {
pub fn new(topology: T) -> Self {
Self {
topology,
scores: Vec::new(),
impl<T: Topology + FileSystem> FileInterpret<T> {
pub fn new(score: FileScore) -> Self {
FileInterpret {
score,
_marker: std::marker::PhantomData,
}
}
}
pub fn register_score<S>(&mut self, score: S)
where
S: Score<T> + 'static,
{
println!(
"Registering score '{}' for topology '{}'",
score.name(),
self.topology.name()
);
self.scores.push(Box::new(score));
}
pub fn orchestrate(&self) -> Result<(), String> {
println!("Orchestrating topology '{}'", self.topology.name());
for score in &self.scores {
let interpret = score.compile()?;
interpret.execute(&self.topology)?;
impl<T: Topology + FileSystem> Interpret<T> for FileInterpret<T> {
fn execute(&self) {
match &self.score.content {
Some(content) => {
println!("File interpret is writing to {}: {}", self.score.path, content);
// In a real implementation: topology.write_file(&self.score.path, content);
},
None => {
println!("File interpret is reading from {}", self.score.path);
// In a real implementation: let content = topology.read_file(&self.score.path);
}
}
Ok(())
}
}
fn main() {
let linux_host = LinuxHostTopology::new("dev-machine".to_string(), "localhost".to_string());
let mut linux_maestro = Maestro::new(linux_host);
linux_maestro.register_score(CommandScore::new(
"check-disk".to_string(),
"df".to_string(),
vec!["-h".to_string()],
));
linux_maestro.orchestrate().unwrap();
// This would fail to compile if we tried to register a K8sResourceScore
// because LinuxHostTopology doesn't implement KubernetesCapability
//linux_maestro.register_score(K8sResourceScore::new(
// "...".to_string(),
// "...".to_string(),
//));
// Create a K3D topology which has both Command and Kubernetes capabilities
let k3d_host = LinuxHostTopology::new("k3d-host".to_string(), "localhost".to_string());
let k3d_topology = K3DTopology::new(
"dev-cluster".to_string(),
k3d_host,
"devcluster".to_string(),
// Create our topologies
let linux = LinuxHostTopology { hostname: "server1.example.com".to_string() };
let bare_metal = BareMetalTopology { device_id: "device001".to_string() };
// Create our maestros
let linux_maestro = Maestro::new(linux);
let bare_metal_maestro = Maestro::new(bare_metal);
// Create scores
let command_score = CommandScore::new(
"List Files".to_string(),
vec!["ls".to_string(), "-la".to_string()]
);
// Create a maestro for the K3D topology
let mut k3d_maestro = Maestro::new(k3d_topology);
// We can register both command scores and kubernetes scores
k3d_maestro.register_score(CommandScore::new(
"check-nodes".to_string(),
"kubectl".to_string(),
vec!["get".to_string(), "nodes".to_string()],
));
k3d_maestro.register_score(K8sResourceScore::new(
"deploy-nginx".to_string(),
r#"
apiVersion: apps/v1
kind: Deployment
metadata:
name: nginx
spec:
replicas: 1
selector:
matchLabels:
app: nginx
template:
metadata:
labels:
app: nginx
spec:
containers:
- name: nginx
image: nginx:latest
ports:
- containerPort: 80
"#
.to_string(),
));
// Orchestrate both topologies
linux_maestro.orchestrate().unwrap();
k3d_maestro.orchestrate().unwrap();
let file_read_score = FileScore::new_read(
"Read Config".to_string(),
"/etc/config.json".to_string()
);
// This will work because LinuxHostTopology implements CommandExecution
linux_maestro.execute_score(command_score.clone());
// This will work because LinuxHostTopology implements FileSystem
linux_maestro.execute_score(file_read_score.clone());
// This will work because BareMetalTopology implements FileSystem
bare_metal_maestro.execute_score(file_read_score);
// This would NOT compile because BareMetalTopology doesn't implement CommandExecution:
// bare_metal_maestro.execute_score(command_score);
// The error would occur at compile time, ensuring type safety
println!("All scores executed successfully!");
}

View File

@ -0,0 +1,314 @@
mod main_gemini25pro;
use std::process::Command;
pub trait Capability {}
pub trait CommandCapability: Capability {
fn execute_command(&self, command: &str, args: &[&str]) -> Result<String, String>;
}
pub trait KubernetesCapability: Capability {
fn apply_manifest(&self, manifest: &str) -> Result<(), String>;
fn get_resource(&self, resource_type: &str, name: &str) -> Result<String, String>;
}
pub trait Topology {
fn name(&self) -> &str;
}
pub trait Score<T: Topology> {
fn compile(&self) -> Result<Box<dyn Interpret<T>>, String>;
fn name(&self) -> &str;
}
pub struct LinuxHostTopology {
name: String,
host: String,
}
impl Capability for LinuxHostTopology {}
impl LinuxHostTopology {
pub fn new(name: String, host: String) -> Self {
Self { name, host }
}
}
impl Topology for LinuxHostTopology {
fn name(&self) -> &str {
&self.name
}
}
impl CommandCapability for LinuxHostTopology {
fn execute_command(&self, command: &str, args: &[&str]) -> Result<String, String> {
println!("Executing on {}: {} {:?}", self.host, command, args);
// In a real implementation, this would SSH to the host and execute the command
let output = Command::new(command)
.args(args)
.output()
.map_err(|e| e.to_string())?;
if output.status.success() {
Ok(String::from_utf8_lossy(&output.stdout).to_string())
} else {
Err(String::from_utf8_lossy(&output.stderr).to_string())
}
}
}
pub struct K3DTopology {
name: String,
linux_host: LinuxHostTopology,
cluster_name: String,
}
impl Capability for K3DTopology {}
impl K3DTopology {
pub fn new(name: String, linux_host: LinuxHostTopology, cluster_name: String) -> Self {
Self {
name,
linux_host,
cluster_name,
}
}
}
impl Topology for K3DTopology {
fn name(&self) -> &str {
&self.name
}
}
impl CommandCapability for K3DTopology {
fn execute_command(&self, command: &str, args: &[&str]) -> Result<String, String> {
self.linux_host.execute_command(command, args)
}
}
impl KubernetesCapability for K3DTopology {
fn apply_manifest(&self, manifest: &str) -> Result<(), String> {
println!("Applying manifest to K3D cluster '{}'", self.cluster_name);
// Write manifest to a temporary file
let temp_file = format!("/tmp/manifest-harmony-temp.yaml");
// Use the linux_host directly to avoid capability trait bounds
self.linux_host
.execute_command("bash", &["-c", &format!("cat > {}", temp_file)])?;
// Apply with kubectl
self.linux_host.execute_command("kubectl", &[
"--context",
&format!("k3d-{}", self.cluster_name),
"apply",
"-f",
&temp_file,
])?;
Ok(())
}
fn get_resource(&self, resource_type: &str, name: &str) -> Result<String, String> {
println!(
"Getting resource {}/{} from K3D cluster '{}'",
resource_type, name, self.cluster_name
);
self.linux_host.execute_command("kubectl", &[
"--context",
&format!("k3d-{}", self.cluster_name),
"get",
resource_type,
name,
"-o",
"yaml",
])
}
}
pub struct CommandScore {
name: String,
command: String,
args: Vec<String>,
}
impl CommandScore {
pub fn new(name: String, command: String, args: Vec<String>) -> Self {
Self {
name,
command,
args,
}
}
}
pub trait Interpret<T: Topology> {
fn execute(&self, topology: &T) -> Result<String, String>;
}
struct CommandInterpret;
impl<T> Interpret<T> for CommandInterpret
where
T: Topology + CommandCapability,
{
fn execute(&self, topology: &T) -> Result<String, String> {
todo!()
}
}
impl<T> Score<T> for CommandScore
where
T: Topology + CommandCapability,
{
fn compile(&self) -> Result<Box<dyn Interpret<T>>, String> {
Ok(Box::new(CommandInterpret {}))
}
fn name(&self) -> &str {
&self.name
}
}
#[derive(Clone)]
pub struct K8sResourceScore {
name: String,
manifest: String,
}
impl K8sResourceScore {
pub fn new(name: String, manifest: String) -> Self {
Self { name, manifest }
}
}
struct K8sResourceInterpret {
score: K8sResourceScore,
}
impl<T: Topology + KubernetesCapability> Interpret<T> for K8sResourceInterpret {
fn execute(&self, topology: &T) -> Result<String, String> {
todo!()
}
}
impl<T> Score<T> for K8sResourceScore
where
T: Topology + KubernetesCapability,
{
fn compile(&self) -> Result<Box<(dyn Interpret<T> + 'static)>, String> {
Ok(Box::new(K8sResourceInterpret {
score: self.clone(),
}))
}
fn name(&self) -> &str {
&self.name
}
}
pub struct Maestro<T: Topology> {
topology: T,
scores: Vec<Box<dyn Score<T>>>,
}
impl<T: Topology> Maestro<T> {
pub fn new(topology: T) -> Self {
Self {
topology,
scores: Vec::new(),
}
}
pub fn register_score<S>(&mut self, score: S)
where
S: Score<T> + 'static,
{
println!(
"Registering score '{}' for topology '{}'",
score.name(),
self.topology.name()
);
self.scores.push(Box::new(score));
}
pub fn orchestrate(&self) -> Result<(), String> {
println!("Orchestrating topology '{}'", self.topology.name());
for score in &self.scores {
let interpret = score.compile()?;
interpret.execute(&self.topology)?;
}
Ok(())
}
}
fn main() {
let linux_host = LinuxHostTopology::new("dev-machine".to_string(), "localhost".to_string());
let mut linux_maestro = Maestro::new(linux_host);
linux_maestro.register_score(CommandScore::new(
"check-disk".to_string(),
"df".to_string(),
vec!["-h".to_string()],
));
linux_maestro.orchestrate().unwrap();
// This would fail to compile if we tried to register a K8sResourceScore
// because LinuxHostTopology doesn't implement KubernetesCapability
//linux_maestro.register_score(K8sResourceScore::new(
// "...".to_string(),
// "...".to_string(),
//));
// Create a K3D topology which has both Command and Kubernetes capabilities
let k3d_host = LinuxHostTopology::new("k3d-host".to_string(), "localhost".to_string());
let k3d_topology = K3DTopology::new(
"dev-cluster".to_string(),
k3d_host,
"devcluster".to_string(),
);
// Create a maestro for the K3D topology
let mut k3d_maestro = Maestro::new(k3d_topology);
// We can register both command scores and kubernetes scores
k3d_maestro.register_score(CommandScore::new(
"check-nodes".to_string(),
"kubectl".to_string(),
vec!["get".to_string(), "nodes".to_string()],
));
k3d_maestro.register_score(K8sResourceScore::new(
"deploy-nginx".to_string(),
r#"
apiVersion: apps/v1
kind: Deployment
metadata:
name: nginx
spec:
replicas: 1
selector:
matchLabels:
app: nginx
template:
metadata:
labels:
app: nginx
spec:
containers:
- name: nginx
image: nginx:latest
ports:
- containerPort: 80
"#
.to_string(),
));
// Orchestrate both topologies
linux_maestro.orchestrate().unwrap();
k3d_maestro.orchestrate().unwrap();
}

View File

@ -0,0 +1,369 @@
// Import necessary items (though for this example, few are needed beyond std)
use std::fmt;
// --- Error Handling ---
// A simple error type for demonstration purposes. In a real app, use `thiserror` or `anyhow`.
#[derive(Debug)]
enum OrchestrationError {
CommandFailed(String),
KubeClientError(String),
TopologySetupFailed(String),
}
impl fmt::Display for OrchestrationError {
fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
match self {
OrchestrationError::CommandFailed(e) => write!(f, "Command execution failed: {}", e),
OrchestrationError::KubeClientError(e) => write!(f, "Kubernetes client error: {}", e),
OrchestrationError::TopologySetupFailed(e) => write!(f, "Topology setup failed: {}", e),
}
}
}
impl std::error::Error for OrchestrationError {}
// Define a common Result type
type Result<T> = std::result::Result<T, Box<dyn std::error::Error>>;
// --- 1. Capability Specification (as Traits) ---
/// Capability trait representing the ability to run Linux commands.
/// This follows the "Parse, Don't Validate" idea implicitly - if you have an object
/// implementing this, you know you *can* run commands, no need to check later.
trait LinuxOperations {
fn run_command(&self, command: &str) -> Result<String>;
}
/// A mock Kubernetes client trait for demonstration.
trait KubeClient {
fn apply_manifest(&self, manifest: &str) -> Result<()>;
fn get_pods(&self, namespace: &str) -> Result<Vec<String>>;
}
/// Mock implementation of a KubeClient.
struct MockKubeClient {
cluster_name: String,
}
impl KubeClient for MockKubeClient {
fn apply_manifest(&self, manifest: &str) -> Result<()> {
println!(
"[{}] Applying Kubernetes manifest:\n---\n{}\n---",
self.cluster_name, manifest
);
// Simulate success or failure
if manifest.contains("invalid") {
Err(Box::new(OrchestrationError::KubeClientError(
"Invalid manifest content".into(),
)))
} else {
Ok(())
}
}
fn get_pods(&self, namespace: &str) -> Result<Vec<String>> {
println!(
"[{}] Getting pods in namespace '{}'",
self.cluster_name, namespace
);
Ok(vec![
format!("pod-a-12345-{}-{}", namespace, self.cluster_name),
format!("pod-b-67890-{}-{}", namespace, self.cluster_name),
])
}
}
/// Capability trait representing access to a Kubernetes cluster.
/// This follows Rust Embedded WG's "Zero-Cost Abstractions" - the trait itself
/// adds no runtime overhead, only compile-time structure.
trait KubernetesCluster {
// Provides access to a Kubernetes client instance.
// Using `impl Trait` in return position for flexibility.
fn get_kube_client(&self) -> Result<impl KubeClient>;
}
// --- 2. Topology Implementations ---
// Topologies implement the capabilities they provide.
/// Represents a basic Linux host.
#[derive(Debug, Clone)]
struct LinuxHostTopology {
hostname: String,
// In a real scenario: SSH connection details, etc.
}
impl LinuxHostTopology {
fn new(hostname: &str) -> Self {
println!("Initializing LinuxHostTopology for {}", hostname);
Self {
hostname: hostname.to_string(),
}
}
}
// LinuxHostTopology provides LinuxOperations capability.
impl LinuxOperations for LinuxHostTopology {
fn run_command(&self, command: &str) -> Result<String> {
println!("[{}] Running command: '{}'", self.hostname, command);
// Simulate command execution (e.g., via SSH)
if command.starts_with("fail") {
Err(Box::new(OrchestrationError::CommandFailed(format!(
"Command '{}' failed",
command
))))
} else {
Ok(format!("Output of '{}' on {}", command, self.hostname))
}
}
}
/// Represents a K3D (Kubernetes in Docker) cluster running on a host.
#[derive(Debug, Clone)]
struct K3DTopology {
cluster_name: String,
host_os: String, // Example: might implicitly run commands on the underlying host
// In a real scenario: Kubeconfig path, Docker client, etc.
}
impl K3DTopology {
fn new(cluster_name: &str) -> Self {
println!("Initializing K3DTopology for cluster {}", cluster_name);
Self {
cluster_name: cluster_name.to_string(),
host_os: "Linux".to_string(), // Assume k3d runs on Linux for this example
}
}
}
// K3DTopology provides KubernetesCluster capability.
impl KubernetesCluster for K3DTopology {
fn get_kube_client(&self) -> Result<impl KubeClient> {
println!("[{}] Creating mock Kubernetes client", self.cluster_name);
// In a real scenario, this would initialize a client using kubeconfig etc.
Ok(MockKubeClient {
cluster_name: self.cluster_name.clone(),
})
}
}
// K3DTopology *also* provides LinuxOperations (e.g., for running commands inside nodes or on the host managing k3d).
impl LinuxOperations for K3DTopology {
fn run_command(&self, command: &str) -> Result<String> {
println!(
"[{} on {} host] Running command: '{}'",
self.cluster_name, self.host_os, command
);
// Simulate command execution (maybe `docker exec` or similar)
if command.starts_with("fail") {
Err(Box::new(OrchestrationError::CommandFailed(format!(
"Command '{}' failed within k3d context",
command
))))
} else {
Ok(format!(
"Output of '{}' within k3d cluster {}",
command, self.cluster_name
))
}
}
}
// --- 3. Score Implementations ---
// Scores require capabilities via trait bounds on their execution logic.
/// Base trait for identifying scores. Could be empty or hold metadata.
trait Score {
fn name(&self) -> &'static str;
// We don't put execute here, as its signature depends on required capabilities.
}
/// A score that runs a shell command on a Linux host.
#[derive(Debug)]
struct CommandScore {
command: String,
}
impl Score for CommandScore {
fn name(&self) -> &'static str {
"CommandScore"
}
}
impl CommandScore {
fn new(command: &str) -> Self {
Self {
command: command.to_string(),
}
}
/// Execute method is generic over T, but requires T implements LinuxOperations.
/// This follows the "Scores as Polymorphic Functions" idea.
fn execute<T: LinuxOperations + ?Sized>(&self, topology: &T) -> Result<()> {
println!("Executing Score: {}", Score::name(self));
let output = topology.run_command(&self.command)?;
println!("Command Score Output: {}", output);
Ok(())
}
}
/// A score that applies a Kubernetes resource manifest.
#[derive(Debug)]
struct K8sResourceScore {
manifest_path: String, // Path or content
}
impl Score for K8sResourceScore {
fn name(&self) -> &'static str {
"K8sResourceScore"
}
}
impl K8sResourceScore {
fn new(manifest_path: &str) -> Self {
Self {
manifest_path: manifest_path.to_string(),
}
}
/// Execute method requires T implements KubernetesCluster.
fn execute<T: KubernetesCluster + ?Sized>(&self, topology: &T) -> Result<()> {
println!("Executing Score: {}", Score::name(self));
let client = topology.get_kube_client()?;
let manifest_content = format!(
"apiVersion: v1\nkind: Pod\nmetadata:\n name: my-pod-from-{}",
self.manifest_path
); // Simulate reading file
client.apply_manifest(&manifest_content)?;
println!(
"K8s Resource Score applied manifest: {}",
self.manifest_path
);
Ok(())
}
}
// --- 4. Maestro (The Orchestrator) ---
// This version of Maestro uses a helper trait (`ScoreRunner`) to enable
// storing heterogeneous scores while preserving compile-time checks.
/// A helper trait to erase the specific capability requirements *after*
/// the compiler has verified them, allowing storage in a Vec.
/// The verification happens in the blanket impls below.
trait ScoreRunner<T> {
// T is the concrete Topology type
fn run(&self, topology: &T) -> Result<()>;
fn name(&self) -> &'static str;
}
// Blanket implementation: A CommandScore can be run on any Topology T
// *if and only if* T implements LinuxOperations.
// The compiler checks this bound when `add_score` is called.
impl<T: LinuxOperations> ScoreRunner<T> for CommandScore {
fn run(&self, topology: &T) -> Result<()> {
self.execute(topology) // Call the capability-specific execute method
}
fn name(&self) -> &'static str {
Score::name(self)
}
}
// Blanket implementation: A K8sResourceScore can be run on any Topology T
// *if and only if* T implements KubernetesCluster.
impl<T: KubernetesCluster> ScoreRunner<T> for K8sResourceScore {
fn run(&self, topology: &T) -> Result<()> {
self.execute(topology) // Call the capability-specific execute method
}
fn name(&self) -> &'static str {
Score::name(self)
}
}
/// The Maestro orchestrator, strongly typed to a specific Topology `T`.
struct Maestro<T> {
topology: T,
// Stores type-erased runners, but addition is type-safe.
scores: Vec<Box<dyn ScoreRunner<T>>>,
}
impl<T> Maestro<T> {
/// Creates a new Maestro instance bound to a specific topology.
fn new(topology: T) -> Self {
println!("Maestro initialized.");
Maestro {
topology,
scores: Vec::new(),
}
}
/// Adds a score to the Maestro.
/// **Compile-time check happens here!**
/// The `S: ScoreRunner<T>` bound ensures that the score `S` provides an
/// implementation of `ScoreRunner` *for the specific topology type `T`*.
/// The blanket impls above ensure this is only possible if `T` has the
/// required capabilities for `S`.
/// This directly follows the "Theoretical Example: The Compiler as an Ally".
fn add_score<S>(&mut self, score: S)
where
S: Score + ScoreRunner<T> + 'static, // S must be runnable on *this* T
{
println!("Registering score: {}", Score::name(&score));
self.scores.push(Box::new(score));
}
/// Runs all registered scores sequentially on the topology.
fn run_all(&self) -> Vec<Result<()>> {
println!("\n--- Running all scores ---");
self.scores
.iter()
.map(|score_runner| {
println!("---");
let result = score_runner.run(&self.topology);
match &result {
Ok(_) => println!("Score '{}' completed successfully.", score_runner.name()),
Err(e) => eprintln!("Score '{}' failed: {}", score_runner.name(), e),
}
result
})
.collect()
}
}
// --- 5. Example Usage ---
fn main() {
println!("=== Scenario 1: Linux Host Topology ===");
let linux_host = LinuxHostTopology::new("server1.example.com");
let mut maestro_linux = Maestro::new(linux_host);
// Add scores compatible with LinuxHostTopology (which has LinuxOperations)
maestro_linux.add_score(CommandScore::new("uname -a"));
maestro_linux.add_score(CommandScore::new("ls -l /tmp"));
// *** Compile-time Error Example ***
// Try adding a score that requires KubernetesCluster capability.
// This line WILL NOT COMPILE because LinuxHostTopology does not implement KubernetesCluster,
// therefore K8sResourceScore does not implement ScoreRunner<LinuxHostTopology>.
// maestro_linux.add_score(K8sResourceScore::new("my-app.yaml"));
// Uncomment the line above to see the compiler error! The error message will
// likely point to the `ScoreRunner<LinuxHostTopology>` bound not being satisfied
// for `K8sResourceScore`.
let results_linux = maestro_linux.run_all();
println!("\nLinux Host Results: {:?}", results_linux);
println!("\n=== Scenario 2: K3D Topology ===");
let k3d_cluster = K3DTopology::new("dev-cluster");
let mut maestro_k3d = Maestro::new(k3d_cluster);
// Add scores compatible with K3DTopology (which has LinuxOperations AND KubernetesCluster)
maestro_k3d.add_score(CommandScore::new("pwd")); // Uses LinuxOperations
maestro_k3d.add_score(K8sResourceScore::new("nginx-deployment.yaml")); // Uses KubernetesCluster
maestro_k3d.add_score(K8sResourceScore::new("invalid-service.yaml")); // Test error case
maestro_k3d.add_score(CommandScore::new("fail please")); // Test error case
let results_k3d = maestro_k3d.run_all();
println!("\nK3D Cluster Results: {:?}", results_k3d);
println!("\n=== Compile-Time Safety Demonstrated ===");
println!("(Check the commented-out line in the code for the compile error example)");
}

View File

@ -0,0 +1,492 @@
use std::any::Any;
use std::fmt::Debug;
use std::process::Command;
pub trait Capability {}
pub trait CommandCapability: Capability {
fn execute_command(&self, command: &str, args: &Vec<String>) -> Result<String, String>;
}
pub trait KubernetesCapability: Capability {
fn apply_manifest(&self, manifest: &str) -> Result<(), String>;
fn get_resource(&self, resource_type: &str, name: &str) -> Result<String, String>;
}
pub trait Topology {
fn name(&self) -> &str;
}
pub trait Interpret<T: Topology> {
fn execute(&self, topology: &T) -> Result<String, String>;
}
// --- Score Definition Structs (Concrete) ---
// CommandScore struct remains the same
#[derive(Debug, Clone)] // Added Debug/Clone for easier handling
pub struct CommandScore {
name: String,
command: String,
args: Vec<String>,
}
impl CommandScore {
pub fn new(name: String, command: String, args: Vec<String>) -> Self {
Self { name, command, args }
}
}
// K8sResourceScore struct remains the same
#[derive(Debug, Clone)]
pub struct K8sResourceScore {
name: String,
manifest: String,
}
impl K8sResourceScore {
pub fn new(name: String, manifest: String) -> Self {
Self { name, manifest }
}
}
// --- Metadata / Base Score Trait (Non-Generic) ---
// Trait for common info and enabling downcasting later if needed
pub trait ScoreDefinition: Debug + Send + Sync {
fn name(&self) -> &str;
// Method to allow downcasting
fn as_any(&self) -> &dyn Any;
// Optional: Could add methods for description, parameters etc.
// fn description(&self) -> &str;
// Optional but potentially useful: A way to clone the definition
fn box_clone(&self) -> Box<dyn ScoreDefinition>;
}
// Implement Clone for Box<dyn ScoreDefinition>
impl Clone for Box<dyn ScoreDefinition> {
fn clone(&self) -> Self {
self.box_clone()
}
}
// Implement ScoreDefinition for your concrete score types
impl ScoreDefinition for CommandScore {
fn name(&self) -> &str {
&self.name
}
fn as_any(&self) -> &dyn Any {
self
}
fn box_clone(&self) -> Box<dyn ScoreDefinition> {
Box::new(self.clone())
}
}
impl ScoreDefinition for K8sResourceScore {
fn name(&self) -> &str {
&self.name
}
fn as_any(&self) -> &dyn Any {
self
}
fn box_clone(&self) -> Box<dyn ScoreDefinition> {
Box::new(self.clone())
}
}
// --- Score Compatibility Trait (Generic over T) ---
// This remains largely the same, ensuring compile-time checks
pub trait Score<T: Topology>: ScoreDefinition {
// No need for name() here, it's in ScoreDefinition
fn compile(&self) -> Result<Box<dyn Interpret<T>>, String>;
}
// --- Implementations of Score<T> (Crucial Link) ---
// CommandScore implements Score<T> for any T with CommandCapability
impl<T> Score<T> for CommandScore
where
T: Topology + CommandCapability + 'static, // Added 'static bound often needed for Box<dyn>
// Self: ScoreDefinition // This bound is implicit now
{
fn compile(&self) -> Result<Box<dyn Interpret<T>>, String> {
// Pass necessary data from self to CommandInterpret
Ok(Box::new(CommandInterpret {
command: self.command.clone(),
args: self.args.clone(),
}))
}
}
// K8sResourceScore implements Score<T> for any T with KubernetesCapability
impl<T> Score<T> for K8sResourceScore
where
T: Topology + KubernetesCapability + 'static,
// Self: ScoreDefinition
{
fn compile(&self) -> Result<Box<dyn Interpret<T>>, String> {
Ok(Box::new(K8sResourceInterpret {
manifest: self.manifest.clone(), // Pass needed data
}))
}
}
// --- Interpret Implementations ---
// Need to hold the actual data now
struct CommandInterpret {
command: String,
args: Vec<String>, // Or owned Strings if lifetime is tricky
}
impl<'a, T> Interpret<T> for CommandInterpret
where
T: Topology + CommandCapability,
{
fn execute(&self, topology: &T) -> Result<String, String> {
// Now uses data stored in self
topology.execute_command(&self.command, &self.args)
}
}
struct K8sResourceInterpret {
manifest: String,
}
impl<T: Topology + KubernetesCapability> Interpret<T> for K8sResourceInterpret {
fn execute(&self, topology: &T) -> Result<String, String> {
topology.apply_manifest(&self.manifest)?;
// apply_manifest returns Result<(), String>, adapt if needed
Ok(format!("Applied manifest for {}", topology.name())) // Example success message
}
}
// --- Maestro ---
// Maestro remains almost identical, leveraging the Score<T> bound
pub struct Maestro<T: Topology> {
topology: T,
// Stores Score<T> trait objects, ensuring compatibility
scores: Vec<Box<dyn Score<T>>>,
}
impl<T: Topology + 'static> Maestro<T> { // Often need T: 'static here
pub fn new(topology: T) -> Self {
Self {
topology,
scores: Vec::new(),
}
}
// This method signature is key - it takes a concrete S
// and the compiler checks if S implements Score<T>
pub fn register_score<S>(&mut self, score: S) -> Result<(), String>
where
S: Score<T> + ScoreDefinition + Clone + 'static, // Ensure S is a Score for *this* T
// We might need S: Clone if we want to store Box::new(score)
// Alternatively, accept Box<dyn ScoreDefinition> and try to downcast/wrap
{
println!(
"Registering score '{}' for topology '{}'",
score.name(),
self.topology.name()
);
// The compiler has already guaranteed that S implements Score<T>
// We need to box it as dyn Score<T>
self.scores.push(Box::new(score));
Ok(())
}
// Alternative registration if you have Box<dyn ScoreDefinition>
pub fn register_score_definition(&mut self, score_def: Box<dyn ScoreDefinition>) -> Result<(), String>
where
T: Topology + CommandCapability + KubernetesCapability + 'static, // Example: list all needed caps here, or use generics + downcasting
{
println!(
"Attempting to register score '{}' for topology '{}'",
score_def.name(),
self.topology.name()
);
// Downcast to check concrete type and then check compatibility
if let Some(cs) = score_def.as_any().downcast_ref::<CommandScore>() {
// Check if T satisfies CommandScore's requirements (CommandCapability)
// This check is somewhat manual or needs restructuring if we avoid listing all caps
// A simpler way is to just try to create the Box<dyn Score<T>>
let boxed_score: Box<dyn Score<T>> = Box::new(cs.clone()); // This relies on the blanket impls
self.scores.push(boxed_score);
Ok(())
} else if let Some(ks) = score_def.as_any().downcast_ref::<K8sResourceScore>() {
// Check if T satisfies K8sResourceScore's requirements (KubernetesCapability)
let boxed_score: Box<dyn Score<T>> = Box::new(ks.clone());
self.scores.push(boxed_score);
Ok(())
} else {
Err(format!("Score '{}' is of an unknown type or incompatible", score_def.name()))
}
// This downcasting approach in Maestro slightly undermines the full compile-time
// check unless designed carefully. The generic `register_score<S: Score<T>>` is safer.
}
pub fn orchestrate(&self) -> Result<(), String> {
println!("Orchestrating topology '{}'", self.topology.name());
for score in &self.scores {
println!("Compiling score '{}'", score.name()); // Use name() from ScoreDefinition
let interpret = score.compile()?;
println!("Executing score '{}'", score.name());
interpret.execute(&self.topology)?;
}
Ok(())
}
}
// --- TUI Example ---
struct ScoreItem {
// Holds the definition/metadata, NOT the Score<T> trait object
definition: Box<dyn ScoreDefinition>,
}
struct HarmonyTui {
// List of available score *definitions*
available_scores: Vec<ScoreItem>,
// Example: Maybe maps topology names to Maestros
// maestros: HashMap<String, Box<dyn Any>>, // Storing Maestros generically is another challenge!
}
impl HarmonyTui {
fn new() -> Self {
HarmonyTui { available_scores: vec![] }
}
fn add_available_score(&mut self, score_def: Box<dyn ScoreDefinition>) {
self.available_scores.push(ScoreItem { definition: score_def });
}
fn display_scores(&self) {
println!("Available Scores:");
for (i, item) in self.available_scores.iter().enumerate() {
println!("{}: {}", i, item.definition.name());
}
}
fn execute_score(&self, score: ScoreItem) {
score.definition.
}
// Example: Function to add a selected score to a specific Maestro
// This function would need access to the Maestros and handle the types
fn add_selected_score_to_maestro<T>(
&self,
score_index: usize,
maestro: &mut Maestro<T>
) -> Result<(), String>
where
T: Topology + CommandCapability + KubernetesCapability + 'static, // Adjust bounds as needed
{
let score_item = self.available_scores.get(score_index)
.ok_or("Invalid score index")?;
// We have Box<dyn ScoreDefinition>, need to add to Maestro<T>
// Easiest is to downcast and call the generic register_score
if let Some(cs) = score_item.definition.as_any().downcast_ref::<CommandScore>() {
// Compiler checks if CommandScore: Score<T> via register_score's bound
maestro.register_score(cs.clone())?;
Ok(())
} else if let Some(ks) = score_item.definition.as_any().downcast_ref::<K8sResourceScore>() {
// Compiler checks if K8sResourceScore: Score<T> via register_score's bound
maestro.register_score(ks.clone())?;
Ok(())
} else {
Err(format!("Cannot add score '{}': Unknown type or check Maestro compatibility", score_item.definition.name()))
}
}
}
pub struct K3DTopology {
name: String,
linux_host: LinuxHostTopology,
cluster_name: String,
}
impl Capability for K3DTopology {}
impl K3DTopology {
pub fn new(name: String, linux_host: LinuxHostTopology, cluster_name: String) -> Self {
Self {
name,
linux_host,
cluster_name,
}
}
}
impl Topology for K3DTopology {
fn name(&self) -> &str {
&self.name
}
}
impl CommandCapability for K3DTopology {
fn execute_command(&self, command: &str, args: &Vec<String>) -> Result<String, String> {
self.linux_host.execute_command(command, args)
}
}
impl KubernetesCapability for K3DTopology {
fn apply_manifest(&self, manifest: &str) -> Result<(), String> {
println!("Applying manifest to K3D cluster '{}'", self.cluster_name);
// Write manifest to a temporary file
let temp_file = format!("/tmp/manifest-harmony-temp.yaml");
// Use the linux_host directly to avoid capability trait bounds
self.linux_host
.execute_command("bash", &Vec::from(["-c".to_string(), format!("cat > {}", temp_file)]))?;
// Apply with kubectl
self.linux_host.execute_command("kubectl", &Vec::from([
"--context".to_string(),
format!("k3d-{}", self.cluster_name),
"apply".to_string(),
"-f".to_string(),
temp_file.to_string(),
]))?;
Ok(())
}
fn get_resource(&self, resource_type: &str, name: &str) -> Result<String, String> {
println!(
"Getting resource {}/{} from K3D cluster '{}'",
resource_type, name, self.cluster_name
);
self.linux_host.execute_command("kubectl", &Vec::from([
"--context".to_string(),
format!("k3d-{}", self.cluster_name),
"get".to_string(),
resource_type.to_string(),
name.to_string(),
"-o".to_string(),
"yaml".to_string(),
]))
}
}
pub struct LinuxHostTopology {
name: String,
host: String,
}
impl Capability for LinuxHostTopology {}
impl LinuxHostTopology {
pub fn new(name: String, host: String) -> Self {
Self { name, host }
}
}
impl Topology for LinuxHostTopology {
fn name(&self) -> &str {
&self.name
}
}
impl CommandCapability for LinuxHostTopology {
fn execute_command(&self, command: &str, args: &Vec<String>) -> Result<String, String> {
println!("Executing on {}: {} {:?}", self.host, command, args);
// In a real implementation, this would SSH to the host and execute the command
let output = Command::new(command)
.args(args)
.output()
.map_err(|e| e.to_string())?;
if output.status.success() {
Ok(String::from_utf8_lossy(&output.stdout).to_string())
} else {
Err(String::from_utf8_lossy(&output.stderr).to_string())
}
}
}
// --- Main Function Adapated ---
fn main() {
// --- Linux Host ---
let linux_host = LinuxHostTopology::new("dev-machine".to_string(), "localhost".to_string());
let mut linux_maestro = Maestro::new(linux_host);
let df_score = CommandScore::new(
"check-disk".to_string(),
"df".to_string(),
vec!["-h".to_string()],
);
// Registration uses the generic method, compiler checks CommandScore: Score<LinuxHostTopology>
linux_maestro.register_score(df_score.clone()).unwrap(); // clone needed if df_score used later
// --- K3D Host ---
let k3d_host = LinuxHostTopology::new("k3d-host".to_string(), "localhost".to_string());
let k3d_topology = K3DTopology::new(
"dev-cluster".to_string(),
k3d_host,
"devcluster".to_string(),
);
let mut k3d_maestro = Maestro::new(k3d_topology);
let nodes_score = CommandScore::new(
"check-nodes".to_string(),
"kubectl".to_string(),
vec!["get".to_string(), "nodes".to_string()],
);
let nginx_score = K8sResourceScore::new(
"deploy-nginx".to_string(),
// ... manifest string ...
r#"..."#.to_string(),
);
// Compiler checks CommandScore: Score<K3DTopology>
k3d_maestro.register_score(nodes_score.clone()).unwrap();
// Compiler checks K8sResourceScore: Score<K3DTopology>
k3d_maestro.register_score(nginx_score.clone()).unwrap();
// --- TUI Example Usage ---
let mut tui = HarmonyTui::new();
// Add score *definitions* to the TUI
tui.add_available_score(Box::new(df_score));
tui.add_available_score(Box::new(nodes_score));
tui.add_available_score(Box::new(nginx_score));
tui.display_scores();
// Simulate user selecting score 0 (check-disk) and adding to linux_maestro
match tui.add_selected_score_to_maestro(0, &mut linux_maestro) {
Ok(_) => println!("Successfully registered check-disk to linux_maestro via TUI selection"),
Err(e) => println!("Failed: {}", e), // Should succeed
}
// Simulate user selecting score 2 (deploy-nginx) and adding to linux_maestro
match tui.add_selected_score_to_maestro(2, &mut linux_maestro) {
Ok(_) => println!("Successfully registered deploy-nginx to linux_maestro via TUI selection"), // Should fail!
Err(e) => println!("Correctly failed to add deploy-nginx to linux_maestro: {}", e),
// The failure happens inside add_selected_score_to_maestro because the
// maestro.register_score(ks.clone()) call fails the trait bound check
// K8sResourceScore: Score<LinuxHostTopology> is false.
}
// Simulate user selecting score 2 (deploy-nginx) and adding to k3d_maestro
match tui.add_selected_score_to_maestro(2, &mut k3d_maestro) {
Ok(_) => println!("Successfully registered deploy-nginx to k3d_maestro via TUI selection"), // Should succeed
Err(e) => println!("Failed: {}", e),
}
// --- Orchestration ---
println!("\n--- Orchestrating Linux Maestro ---");
linux_maestro.orchestrate().unwrap();
println!("\n--- Orchestrating K3D Maestro ---");
k3d_maestro.orchestrate().unwrap();
}