feat: add derivation parsing

Cargo.toml

@@ -7,3 +7,7 @@ edition = "2021"
 
 [dependencies]
 clap = { version = "4", features = ["derive"] }
+
+serde_json = "1.0"
+serde = "1.0"
+serde_derive = "1.0"

src/main.rs

@@ -6,6 +6,8 @@
 
 #[macro_use]
 extern crate clap;
+#[macro_use]
+extern crate serde_derive;
 
 use clap::Parser;
 

src/nix.rs

@@ -1,13 +1,52 @@
+extern crate serde;
+extern crate serde_json;
+
+use std::collections::HashMap;
+
 use std::io::Error;
 use std::process::Command;
 
-pub fn get_derivation(file: &str) -> Result<Vec<u8>, Error> {
-    let output = Command::new("nix")
-        .arg("show-derivation")
-        .arg("-r")
-        .arg("-f")
-        .arg(file)
-        .output()?;
+#[derive(Debug)]
+#[derive(Serialize)]
+#[derive(Deserialize)]
+#[derive(Clone)]
+struct Derivation {
+    outputs: HashMap<String, Output>,
+
+    #[serde(rename = "inputSrcs")]
+    inputs_sources: Vec<String>,
+
+    #[serde(rename = "inputDrvs")]
+    input_derivations: HashMap<String, Vec<String>>,
+
+    system: String,
+
+    builder: String,
+
+    args: Vec<String>,
+
+    env: HashMap<String, String>,
+
+    #[serde(flatten)]
+    extra: HashMap<String, serde_json::Value>,
+}
+
+impl Derivation {
+    pub fn parse_from_file(file: &str) -> Result<Vec<u8>, Error> {
+        let output = Command::new("nix")
+            .arg("show-derivation")
+            .arg("-r")
+            .arg(file)
+            .output()?;
+
+        Ok(output.stdout)
+    }
+}
 
-    Ok(output.stdout)
+#[derive(Debug)]
+#[derive(Serialize)]
+#[derive(Deserialize)]
+#[derive(Clone)]
+struct Output {
+    path: String,
 }