feat: add pretty print output format

src/main.rs

@@ -26,7 +26,7 @@ struct NixToSBOM {
     #[clap(long, short)]
     file_path: Option<String>,
 
-    /// Output format for the SBOM manifest. Defaults to CycloneDX
+    /// Output format for the SBOM manifest. Defaults to cdx (CycloneDX).
     #[clap(long)]
     format: Option<String>,
 
@@ -113,6 +113,9 @@ fn main() -> Result<std::process::ExitCode, Box<dyn std::error::Error>> {
             );
             return Ok(std::process::ExitCode::FAILURE);
         }
+        crate::sbom::Format::PrettyPrint => {
+            println!("{}", crate::nix::pretty_print_package_graph(&package_graph));
+        }
     };
 
     Ok(std::process::ExitCode::SUCCESS)

src/nix.rs

@@ -148,6 +148,20 @@ impl Derivation {
         }
         vec![]
     }
+
+    pub fn pretty_print(&self) -> Vec<PrettyPrintLine> {
+        let mut response: Vec<PrettyPrintLine> = vec![];
+        if let Some(name) = self.get_name() {
+            response.push(PrettyPrintLine::new(name, 0));
+        } else {
+            response.push(PrettyPrintLine::new("unknown derivation?", 0));
+        }
+        if let Some(url) = self.get_url() {
+            response.push(PrettyPrintLine::new(format!("url: {}", url), 1));
+        }
+
+        response
+    }
 }
 
 #[derive(Debug)]
@@ -206,6 +220,24 @@ pub struct Meta {
     pub packages: HashMap<String, PackageMeta>,
 }
 
+#[derive(Debug)]
+#[derive(Default)]
+pub struct PackageURL {
+    pub scheme: String,
+    pub host: String,
+    pub path: Vec<String>,
+    pub query_params: HashMap<String, String>,
+}
+
+impl PackageURL {
+    pub fn to_string(&self) -> String {
+        let mut full_path = self.path.join("/");
+
+        // TODO add the query params
+        format!("{}://{}/{}", self.scheme, self.host, full_path)
+    }
+}
+
 #[derive(Debug)]
 #[derive(Clone)]
 #[derive(Deserialize)]
@@ -409,8 +441,35 @@ pub struct PackageNode {
     pub children: HashSet<String>,
 }
 
+impl PackageNode {
+    pub fn pretty_print(&self) -> Vec<PrettyPrintLine> {
+        let mut response: Vec<PrettyPrintLine> = vec![];
+        response
+    }
+}
+
 pub type PackageGraph = HashMap<String, PackageNode>;
 
+pub fn pretty_print_package_graph(package_graph: &PackageGraph) -> String {
+    let mut lines: Vec<PrettyPrintLine> = vec![];
+    let mut response = "".to_string();
+
+    for (derivation_path, package_node) in package_graph {
+        for line in package_node.package.pretty_print() {
+            lines.push(line);
+        }
+        for line in package_node.main_derivation.pretty_print() {
+            lines.push(line);
+        }
+    }
+
+    for line in lines {
+        response += &line.to_string();
+        response += "\n";
+    }
+    response
+}
+
 // Small struct to make it easier to pretty-print the
 // internal representation for the package graph.
 #[derive(Debug)]

src/sbom.rs

@@ -1,9 +1,11 @@
 pub const CYCLONE_DX_NAME: &str = "CycloneDX";
 pub const SPDX_NAME: &str = "SPDX";
+pub const PRETTY_PRINT_NAME: &str = "pretty-print";
 
 pub enum Format {
     SPDX,
     CycloneDX,
+    PrettyPrint,
 }
 
 impl Format {
@@ -14,20 +16,26 @@ impl Format {
         if format.ends_with("cdx") {
             return Some(Format::CycloneDX);
         }
+        if format.ends_with("pretty") {
+            return Some(Format::PrettyPrint);
+        }
         None
     }
 
     pub fn to_pretty_name(&self) -> String {
         match self {
             crate::sbom::Format::CycloneDX => CYCLONE_DX_NAME.to_string(),
             crate::sbom::Format::SPDX => SPDX_NAME.to_string(),
+            crate::sbom::Format::PrettyPrint => PRETTY_PRINT_NAME.to_string(),
         }
     }
 
     pub fn get_default_serialization_format(&self) -> SerializationFormat {
         match self {
             crate::sbom::Format::CycloneDX => crate::sbom::SerializationFormat::JSON,
             crate::sbom::Format::SPDX => crate::sbom::SerializationFormat::JSON,
+            // We don't really care which value is returned in this case.
+            crate::sbom::Format::PrettyPrint => crate::sbom::SerializationFormat::XML,
         }
     }
 }