om hack: Initialize (#319)

#316 

This doesn't do much right now, but renders the Markdown from
`om.hack.default.readme`. Spec will change in future iterations.

<img width="1058" alt="image"
src="https://github.com/user-attachments/assets/7514a389-eecc-418c-b444-5957f4518527">

Cargo.toml

@@ -5,6 +5,7 @@ members = [
   "crates/omnix-common",
   "crates/omnix-cli",
   "crates/omnix-init",
+  "crates/omnix-hack",
   "crates/nix_rs",
   "crates/nixci",
   "crates/nix_health",
@@ -40,6 +41,7 @@ nix_rs = { version = "1.0.0", path = "./crates/nix_rs" }
 nonempty = { version = "0.10.0", features = ["serialize"] }
 omnix-common = { version = "0.1.0", path = "./crates/omnix-common" }
 omnix-init = { version = "0.1.0", path = "./crates/omnix-init" }
+omnix-hack = { version = "0.1.0", path = "./crates/omnix-hack" }
 os_info = "3.7.0"
 reqwest = { version = "0.11", features = ["blocking", "json"] }
 regex = "1.9.3"

crates/nix_rs/src/command.rs

@@ -74,14 +74,14 @@ static NIXCMD: OnceCell<NixCmd> = OnceCell::const_new();
 /// rest of the instrumentation parameters.
 #[instrument(name = "command")]
 pub fn trace_cmd(cmd: &tokio::process::Command) {
-    trace_cmd_with("🐚", cmd);
+    trace_cmd_with("〕", cmd);
 }
 
 /// Like [trace_cmd] but with a custom icon
 #[instrument(name = "command")]
 pub fn trace_cmd_with(icon: &str, cmd: &tokio::process::Command) {
     use colored::Colorize;
-    tracing::info!("{} {}️", icon, to_cli(cmd).bright_blue());
+    tracing::info!("{} {}️", icon, to_cli(cmd).dimmed());
 }
 
 impl NixCmd {

crates/omnix-cli/Cargo.toml

@@ -26,6 +26,7 @@ nix_health = { workspace = true }
 nix_rs = { workspace = true }
 omnix-common = { workspace = true }
 omnix-init = { workspace = true }
+omnix-hack = { workspace = true }
 tabled = { workspace = true }
 tokio = { workspace = true }
 tracing = { workspace = true }

crates/omnix-cli/src/command/core.rs

@@ -7,6 +7,8 @@ pub enum Command {
 
     Init(super::init::InitCommand),
 
+    Hack(super::hack::HackCommand),
+
     CI(super::ci::CICommand),
 
     Health(super::health::HealthCommand),
@@ -24,6 +26,7 @@ impl Command {
         match self {
             Command::Show(cmd) => cmd.run().await,
             Command::Init(cmd) => cmd.run().await,
+            Command::Hack(cmd) => cmd.run().await,
             Command::CI(cmd) => cmd.run(verbosity).await,
             Command::Health(cmd) => cmd.run().await,
             Command::Completion(cmd) => cmd.run(),

crates/omnix-cli/src/command/hack.rs

@@ -0,0 +1,12 @@
+use clap::Parser;
+
+/// Prepare to hack on a flake project
+#[derive(Parser, Debug)]
+pub struct HackCommand {}
+
+impl HackCommand {
+    pub async fn run(&self) -> anyhow::Result<()> {
+        omnix_hack::core::hack_on().await?;
+        Ok(())
+    }
+}

crates/omnix-cli/src/command/mod.rs

@@ -1,6 +1,7 @@
 pub mod ci;
 pub mod completion;
 pub mod core;
+pub mod hack;
 pub mod health;
 pub mod init;
 pub mod show;

crates/omnix-hack/Cargo.toml

@@ -0,0 +1,26 @@
+[package]
+authors = ["Sridhar Ratnakumar <[email protected]>"]
+edition = "2021"
+# If you change the name here, you must also do it in flake.nix (and run `cargo generate-lockfile` afterwards)
+name = "omnix-hack"
+version = "0.1.0"
+repository = "https://github.com/juspay/omnix"
+description = "Implementation for the `om hack` command"
+license = "Apache-2.0"
+
+[lib]
+crate-type = ["cdylib", "rlib"]
+
+# See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
+
+[dependencies]
+anyhow = { workspace = true }
+lazy_static = { workspace = true }
+nix_rs = { workspace = true }
+serde = { workspace = true }
+serde_json = { workspace = true }
+syntect = { workspace = true }
+thiserror = { workspace = true }
+tokio = { workspace = true }
+tracing = { workspace = true }
+omnix-common = { workspace = true }

crates/omnix-hack/crate.nix

@@ -0,0 +1,24 @@
+{ flake
+, pkgs
+, lib
+, rust-project
+, ...
+}:
+
+{
+  autoWire = lib.optionals
+    (lib.elem pkgs.system [ "x86_64-linux" "aarch64-darwin" ])
+    [ "doc" "clippy" ];
+  crane.args = {
+    buildInputs = lib.optionals pkgs.stdenv.isDarwin (
+      with pkgs.apple_sdk_frameworks; [
+        IOKit
+      ]
+    );
+    inherit (rust-project.crates."nix_rs".crane.args)
+      DEFAULT_FLAKE_SCHEMAS
+      INSPECT_FLAKE
+      NIX_SYSTEMS
+      ;
+  };
+}

crates/omnix-hack/src/config.rs

@@ -0,0 +1,40 @@
+use serde::Deserialize;
+
+use nix_rs::{command::NixCmd, flake::url::FlakeUrl};
+use omnix_common::config::OmConfig;
+
+use crate::readme::Readme;
+
+#[derive(Debug, Deserialize, Clone)]
+pub struct HackConfig {
+    pub cache: CacheConfig,
+    pub readme: Readme,
+}
+
+#[derive(Debug, Deserialize, Clone)]
+pub struct CacheConfig {
+    pub cachix: CachixConfig,
+}
+
+#[derive(Debug, Deserialize, Clone)]
+pub struct CachixConfig {
+    /// If enabled, configure environment to use the cache.
+    pub enable: bool,
+    /// Name of the cachix cache (`https://<name>.cachix.org`)
+    pub name: String,
+    /// The read-only auth token to use if this is a private cache
+    ///
+    /// If provided, will run `cachix authtoken <auth_token>`.
+    pub auth_token: Option<String>,
+}
+
+impl HackConfig {
+    pub async fn from_flake(url: &FlakeUrl) -> anyhow::Result<Self> {
+        let v = OmConfig::<Self>::from_flake_url(NixCmd::get().await, url, &["om.hack"])
+            .await?
+            .config;
+        v.get("default")
+            .cloned()
+            .ok_or_else(|| anyhow::anyhow!("Missing key default for om.hack"))
+    }
+}

crates/omnix-hack/src/core.rs

@@ -0,0 +1,20 @@
+use std::path::Path;
+
+use nix_rs::flake::url::FlakeUrl;
+use omnix_common::markdown::print_markdown;
+
+use crate::config::HackConfig;
+
+pub async fn hack_on() -> anyhow::Result<()> {
+    let here_flake: FlakeUrl = Into::<FlakeUrl>::into(Path::new("."));
+    let cfg = HackConfig::from_flake(&here_flake).await?;
+
+    // TODO: cachix check
+    // TODO: `om health`
+
+    let pwd = std::env::current_dir()?;
+    eprintln!();
+    print_markdown(&pwd, &cfg.readme.get_markdown()).await?;
+
+    Ok(())
+}

crates/omnix-hack/src/lib.rs

@@ -0,0 +1,3 @@
+pub mod config;
+pub mod core;
+pub mod readme;

crates/omnix-hack/src/readme.rs

@@ -0,0 +1,38 @@
+use serde::Deserialize;
+
+// TODO(idea): What if we provide `om health` like checkmark for each item. Automatically check if the user is in Nix shell or direnv, and ✅ the title accordingly. If not, nudge them to do it.
+const OM_SHELL: &str = r#"## Enter the Nix shell
+
+We recommend that you setup nix-direnv (a convenient template provided at <https://github.com/juspay/nixos-unified-template>), and then run the following in the project terminal to activate the Nix shell:
+
+```sh-session
+direnv allow
+```
+
+From this point, anytime you `cd` to this project directory, the Nix shell will be automatically activated.
+"#;
+
+const OM_IDE: &str = r#"## IDE or editor setup
+
+>[!IMPORTANT] ❗Make sure you have setup `direnv` as stated above.
+
+You can now launch your favourite editor or IDE from inside the Nix devshell. For VSCode in particular, consult <https://nixos.asia/en/vscode>.
+
+"#;
+
+/// The README to display at the end.
+///
+/// Placeholder parameters:
+/// - `OM_SHELL`: Instructions to enter the Nix shell.
+/// - `OM_IDE`: Instructions to setup the IDE.
+#[derive(Debug, Deserialize, Clone)]
+pub struct Readme(pub String);
+
+impl Readme {
+    /// Get the Markdown string, after doing parameter replacements.
+    pub fn get_markdown(&self) -> String {
+        self.0
+            .replace("OM_SHELL", OM_SHELL)
+            .replace("OM_IDE", OM_IDE)
+    }
+}

doc/src/SUMMARY.md

@@ -7,6 +7,7 @@
 - [CLI](om/index.md)
     - [Show](om/show.md)
     - [Health](om/health.md)
+    - [Hack](om/hack.md)
     - [CI](om/ci.md)
     - [Init](om/init.md)
 

doc/src/history.md

@@ -4,6 +4,7 @@
 
 ### Enhancements
 
+- `om hack`: New command
 - `om init`
   - Initial working version of `om init` command
 - `om health`

doc/src/om/hack.md

@@ -0,0 +1,4 @@
+# Hack
+
+> [!TODO]
+> `om hack` is a work in progress

justfile

@@ -14,6 +14,9 @@ alias f := fmt
 watch *ARGS:
     bacon --job run -- -- {{ ARGS }}
 
+run *ARGS:
+    cargo run -p omnix-cli {{ ARGS }}
+
 alias w := watch
 
 # Run CI locally

nix/modules/om.nix

@@ -67,6 +67,37 @@
           # min_disk_space = "2T";
         };
       };
+      hack.default = {
+        # TODO: This is not implemented yet.
+        cache.cachix = {
+          enable = true;
+          name = "om";
+          # authToken = "xxx";
+        };
+        readme = ''
+          🍾 Welcome to the **omnix** project
+
+          OM_SHELL
+
+          OM_IDE
+
+          ## Running `omnix` inside devShell
+
+          This will run `cargo watch` and run the resultant program, and then restart the same as you modify the Rust sources:
+
+          ```sh-session
+          just watch <args>
+          ```
+
+          ## Running `omnix` through Nix
+          ```sh-session
+          nix --accept-flake-config run github:juspay/omnix
+          ```
+
+          ## Read more
+          For details, see [README.md](README.md)
+        '';
+      };
     };
   };
 }