Add run command resource

build.ps1

@@ -120,7 +120,8 @@ $projects = @(
     "y2j",
     "powershellgroup",
     "wmigroup",
-    "resources/brew"
+    "resources/brew",
+    "runcommandonset"
 )
 $pedantic_unclean_projects = @("ntreg")
 $clippy_unclean_projects = @("tree-sitter-dscexpression")

runcommandonset/Cargo.toml

@@ -0,0 +1,14 @@
+[package]
+name = "runcommandonset"
+version = "0.1.0"
+edition = "2021"
+
+# See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
+
+[dependencies]
+atty = { version = "0.2" }
+clap = { version = "4.4", features = ["derive"] }
+serde = { version = "1.0", features = ["derive"] }
+serde_json = { version = "1.0", features = ["preserve_order"] }
+tracing = { version = "0.1.37" }
+tracing-subscriber = { version = "0.3.17", features = ["ansi", "env-filter", "json"] }

runcommandonset/RunCommandOnSet.dsc.resource.json

@@ -0,0 +1,45 @@
+{
+    "$schema": "https://raw.githubusercontent.com/PowerShell/DSC/main/schemas/2023/08/bundled/resource/manifest.json",
+    "description": "Takes a single-command line to execute on set",
+    "type": "Microsoft.DSC.Transitional/RunCommandOnSet",
+    "version": "0.1.0",
+    "get": {
+        "executable": "runcommandonset",
+        "args": [
+          "get"
+        ],
+        "input": "stdin"
+    },
+    "set": {
+        "executable": "runcommandonset",
+        "args": [
+          "set"
+        ],
+        "input": "stdin"
+    },
+    "schema": {
+      "embedded": {
+        "$schema": "http://json-schema.org/draft-07/schema#",
+        "title": "RunCommandOnSet",
+        "type": "object",
+        "required": [
+          "executable"
+        ],
+        "properties": {
+          "arguments": {
+            "title": "The argument(s), if any, to pass to the executable that runs on set",
+            "type": "array"
+          },
+          "executable": {
+            "title": "The executable to run on set",
+            "type": "string"
+          },
+          "exit_code": {
+            "title": "The expected exit code to indicate success, if non-zero",
+            "type": "integer"
+          }
+        },
+        "additionalProperties": false
+      }
+    }
+}

runcommandonset/src/args.rs

@@ -0,0 +1,54 @@
+// Copyright (c) Microsoft Corporation.
+// Licensed under the MIT License.
+
+use clap::{Parser, Subcommand, ValueEnum};
+
+#[derive(Debug, Clone, PartialEq, Eq, ValueEnum)]
+pub enum TraceFormat {
+    Default,
+    Plaintext,
+    Json,
+}
+
+#[derive(Debug, Clone, PartialEq, Eq, ValueEnum)]
+pub enum TraceLevel {
+    Error,
+    Warning,
+    Info,
+    Debug,
+    Trace
+}
+
+#[derive(Parser)]
+#[clap(name = "runcommandonset", version = "0.0.1", about = "Run a command on set", long_about = None)]
+pub struct Arguments {
+
+    #[clap(subcommand)]
+    pub subcommand: SubCommand,
+    #[clap(short = 'l', long, help = "Trace level to use", value_enum, default_value = "info")]
+    pub trace_level: TraceLevel,
+    #[clap(short = 'f', long, help = "Trace format to use", value_enum, default_value = "json")]
+    pub trace_format: TraceFormat,
+}
+
+#[derive(Debug, PartialEq, Eq, Subcommand)]
+pub enum SubCommand {
+    #[clap(name = "get", about = "Get formatted command to run on set.")]
+    Get {
+        #[clap(short = 'a', long, help = "The arguments to pass to the executable.")]
+        arguments: Option<Vec<String>>,
+        #[clap(short = 'e', long, help = "The executable to run.")]
+        executable: Option<String>,
+        #[clap(short = 'c', long, help = "The expected exit code to indicate success, if non-zero.", default_value = "0")]
+        exit_code: i32,
+    },
+    #[clap(name = "set", about = "Run formatted command.")]
+    Set {
+        #[clap(short = 'a', long, help = "The arguments to pass to the executable.")]
+        arguments: Option<Vec<String>>,
+        #[clap(short = 'e', long, help = "The executable to run.")]
+        executable: Option<String>,
+        #[clap(short = 'c', long, help = "The expected exit code to indicate success, if non-zero.", default_value = "0")]
+        exit_code: i32,
+    }
+}

runcommandonset/src/main.rs

@@ -0,0 +1,62 @@
+// Copyright (c) Microsoft Corporation.
+// Licensed under the MIT License.
+
+use atty::Stream;
+use clap::{Parser};
+use std::{io::{self, Read}, process::exit};
+use tracing::{error, warn, debug};
+
+use args::{Arguments, SubCommand};
+use runcommand::{RunCommand};
+use utils::{enable_tracing, invoke_command, parse_input, EXIT_INVALID_ARGS};
+
+pub mod args;
+pub mod runcommand;
+pub mod utils;
+
+fn main() {
+    let args = Arguments::parse();
+    enable_tracing(&args.trace_level, &args.trace_format);
+    warn!("This resource is not idempotent");
+
+    let stdin = if atty::is(Stream::Stdin) {
+        None
+    } else {
+        debug!("Reading input from STDIN");
+        let mut buffer: Vec<u8> = Vec::new();
+        io::stdin().read_to_end(&mut buffer).unwrap();
+        let stdin = match String::from_utf8(buffer) {
+            Ok(stdin) => stdin,
+            Err(e) => {
+                error!("Invalid UTF-8 sequence: {e}");
+                exit(EXIT_INVALID_ARGS);
+            },
+        };
+        // parse_input expects at most 1 input, so wrapping Some(empty input) would throw it off
+        if stdin.is_empty() {
+            debug!("Input from STDIN is empty");
+            None
+        }
+        else {
+            Some(stdin)
+        }
+    };
+
+    let mut command: RunCommand;
+
+    match args.subcommand {
+        SubCommand::Get { arguments, executable, exit_code } => {
+            command = parse_input(arguments, executable, exit_code, stdin);
+        }
+        SubCommand::Set { arguments, executable, exit_code } => {
+            command = parse_input(arguments, executable, exit_code, stdin);
+            let (exit_code, stdout, stderr) = invoke_command(command.executable.as_ref(), command.arguments.clone());
+            // TODO: convert this to tracing json once other PR is merged to handle tracing from resources
+            eprintln!("Stdout: {stdout}");
+            eprintln!("Stderr: {stderr}");
+            command.exit_code = exit_code;
+        }
+    }
+
+    println!("{}", command.to_json());
+}

runcommandonset/src/runcommand.rs

@@ -0,0 +1,31 @@
+// Copyright (c) Microsoft Corporation.
+// Licensed under the MIT License.
+
+use serde::{Deserialize, Serialize};
+
+#[derive(Debug, Deserialize, Clone, PartialEq, Serialize)]
+pub struct RunCommand {
+    pub executable: String,
+    #[serde(skip_serializing_if = "Option::is_none")]
+    pub arguments: Option<Vec<String>>,
+    // default value for exit code is 0
+    #[serde(default, skip_serializing_if = "is_default")]
+    pub exit_code: i32,
+}
+
+impl RunCommand {
+    #[must_use]
+    pub fn to_json(&self) -> String {
+        match serde_json::to_string(self) {
+            Ok(json) => json,
+            Err(e) => {
+                eprintln!("Failed to serialize to JSON: {e}");
+                String::new()
+            }
+        }
+    }
+}
+
+fn is_default<T: Default + PartialEq>(t: &T) -> bool {
+    t == &T::default()
+}

runcommandonset/src/utils.rs

@@ -0,0 +1,178 @@
+// Copyright (c) Microsoft Corporation.
+// Licensed under the MIT License.
+
+use std::{io::Read, process::{Command, exit, Stdio}};
+use tracing::{Level, error, debug};
+use tracing_subscriber::{filter::EnvFilter, layer::SubscriberExt, Layer};
+
+use crate::args::{TraceFormat, TraceLevel};
+use crate::runcommand;
+
+pub const EXIT_INVALID_ARGS: i32 = 1;
+pub const EXIT_DSC_ERROR: i32 = 2;
+pub const EXIT_CODE_MISMATCH: i32 = 3;
+pub const EXIT_INVALID_INPUT: i32 = 4;
+pub const EXIT_PROCESS_TERMINATED: i32 = 5;
+
+/// Initialize `RunCommand` struct from input provided via stdin or via CLI arguments.
+///
+/// # Arguments
+///
+/// * `arguments` - Optional arguments to pass to the command
+/// * `executable` - The command to execute
+/// * `exit_code` - The expected exit code upon success, if non-zero
+/// * `stdin` - Optional JSON or YAML input provided via stdin
+///
+/// # Errors
+///
+/// Error message then exit if the `RunCommand` struct cannot be initialized from the provided inputs.
+pub fn parse_input(arguments: Option<Vec<String>>, executable: Option<String>, exit_code: i32, stdin: Option<String>) -> runcommand::RunCommand {
+    let command: runcommand::RunCommand;
+    if let Some(input) = stdin {
+        debug!("Input: {}", input);
+        command = match serde_json::from_str(&input) {
+            Ok(json) => json,
+            Err(err) => {
+                error!("Error: Input is not valid: {err}");
+                exit(EXIT_INVALID_INPUT);
+            }
+        }
+    } else if let Some(executable) = executable {
+        command = runcommand::RunCommand {
+            executable,
+            arguments,
+            exit_code,
+        };
+    }
+    else {
+        error!("Error: Executable is required when input is not provided via stdin");
+        exit(EXIT_INVALID_INPUT);
+    }
+    command
+}
+
+/// Setup tracing subscriber based on the provided trace level and format.
+///
+/// # Arguments
+///
+/// * `trace_level` - The level of information of to output
+/// * `trace_format` - The format of the output
+///
+/// # Errors
+///
+/// If unable to initialize the tracing subscriber, an error message is printed and tracing is disabled.
+pub fn enable_tracing(trace_level: &TraceLevel, trace_format: &TraceFormat) {
+    // originally implemented in dsc/src/util.rs
+    let tracing_level = match trace_level {
+        TraceLevel::Error => Level::ERROR,
+        TraceLevel::Warning => Level::WARN,
+        TraceLevel::Info => Level::INFO,
+        TraceLevel::Debug => Level::DEBUG,
+        TraceLevel::Trace => Level::TRACE,
+    };
+
+    let filter = EnvFilter::try_from_default_env()
+        .or_else(|_| EnvFilter::try_new("warning"))
+        .unwrap_or_default()
+        .add_directive(tracing_level.into());
+    let layer = tracing_subscriber::fmt::Layer::default().with_writer(std::io::stderr);
+    let fmt = match trace_format {
+        TraceFormat::Default => {
+            layer
+                .with_ansi(true)
+                .with_level(true)
+                .with_line_number(true)
+                .boxed()
+        },
+        TraceFormat::Plaintext => {
+            layer
+                .with_ansi(false)
+                .with_level(true)
+                .with_line_number(false)
+                .boxed()
+        },
+        TraceFormat::Json => {
+            layer
+                .with_ansi(false)
+                .with_level(true)
+                .with_line_number(true)
+                .json()
+                .boxed()
+        }
+    };
+
+    let subscriber = tracing_subscriber::Registry::default().with(fmt).with(filter);
+
+    if tracing::subscriber::set_global_default(subscriber).is_err() {
+        eprintln!("Unable to set global default tracing subscriber.  Tracing is diabled.");
+    }
+}
+
+/// Invoke a command and return the exit code, stdout, and stderr.
+///
+/// # Arguments
+///
+/// * `executable` - The command to execute
+/// * `args` - Optional arguments to pass to the command
+///
+/// # Errors
+///
+/// Error message then exit if the command fails to execute or stdin/stdout/stderr cannot be opened.
+pub fn invoke_command(executable: &str, args: Option<Vec<String>>) -> (i32, String, String) {
+    // originally implemented in dsc_lib/src/dscresources/command_resource.rs
+    debug!("Invoking command {} with args {:?}", executable, args);
+    let mut command = Command::new(executable);
+
+    command.stdout(Stdio::piped());
+    command.stderr(Stdio::piped());
+    if let Some(args) = args {
+        command.args(args);
+    }
+
+    let mut child = match command.spawn() {
+        Ok(child) => child,
+        Err(e) => {
+            error!("Failed to execute {}: {e}", executable);
+            exit(EXIT_DSC_ERROR);
+        }
+    };
+
+    let Some(mut child_stdout) = child.stdout.take() else {
+        error!("Failed to open stdout for {}", executable);
+        exit(EXIT_DSC_ERROR);
+    };
+    let mut stdout_buf = Vec::new();
+    match child_stdout.read_to_end(&mut stdout_buf) {
+        Ok(_) => (),
+        Err(e) => {
+            error!("Failed to read stdout for {}: {e}", executable);
+            exit(EXIT_DSC_ERROR);
+        }
+    }
+
+    let Some(mut child_stderr) = child.stderr.take() else {
+        error!("Failed to open stderr for {}", executable);
+        exit(EXIT_DSC_ERROR);
+    };
+    let mut stderr_buf = Vec::new();
+    match child_stderr.read_to_end(&mut stderr_buf) {
+        Ok(_) => (),
+        Err(e) => {
+            error!("Failed to read stderr for {}: {e}", executable);
+            exit(EXIT_DSC_ERROR);
+        }
+    }
+
+    let exit_status = match child.wait() {
+        Ok(exit_status) => exit_status,
+        Err(e) => {
+            error!("Failed to wait for {}: {e}", executable);
+            exit(EXIT_DSC_ERROR);
+        }
+    };
+
+    let exit_code = exit_status.code().unwrap_or(EXIT_PROCESS_TERMINATED);
+    let stdout = String::from_utf8_lossy(&stdout_buf).to_string();
+    let stderr = String::from_utf8_lossy(&stderr_buf).to_string();
+    (exit_code, stdout, stderr)
+}