feat: ✨ Initial commit

src/main.rs

@@ -0,0 +1,146 @@
+use std::borrow::Borrow;
+/**
+ * A simple personnal tutorial for my first baby steps with Rust.
+ */
+use std::fs;
+use std::fs::File;
+use std::io::{BufReader, Cursor};
+
+
+use chrono::DateTime;
+use clap::Parser;
+use json::object;
+use rss::Channel;
+
+// use log::debug;
+use log::error;
+use log::info;
+// use log::warn;
+
+#[derive(Parser, Debug)]
+#[clap(author, version, about, long_about = None)]
+struct Args {
+    #[clap(short, long, required = true)]
+    input: String,
+
+    #[clap(short, long, default_value_t=String::new())]
+    output: String,
+
+    #[clap(short, long, default_value_t = false)]
+    pretty: bool,
+}
+
+fn main() -> std::io::Result<()> {
+    env_logger::init();
+
+    let args = Args::parse();
+
+    // TODO handle remote http feed discovery by parsing index and search for the feed link
+
+    let channel: Channel;
+
+    if args.input.starts_with("http://") || args.input.starts_with("https://") {
+        // process download
+        match reqwest::blocking::get(args.input).unwrap().bytes() {
+            Ok(content) => {
+                info!("Extracted {} bytes", content.len());
+                let cursor = Cursor::new(content);
+                channel = Channel::read_from(cursor).unwrap();
+            }
+            Err(e) => {
+                error!("{}", e);
+                std::process::exit(1);
+            }
+        }
+    } else {
+        // read locale file
+        let file = File::open(args.input).unwrap();
+        channel = Channel::read_from(BufReader::new(file)).unwrap();
+    }
+
+    // Initialize root object with channel informations, using object macro from json crate
+    let mut data = object! {
+        channel: object!{
+            title: channel.title(),
+            link: channel.link(),
+            description: channel.description(),
+            last_build_date: channel.last_build_date(),
+            language: channel.language(),
+            copyright: channel.copyright(),
+            generator: channel.generator()
+        }
+    };
+
+    // declare an mutable array to populate it with channel item data
+    let mut items_data = json::JsonValue::new_array();
+
+    // populate the items array
+    for item in channel.items() {
+        let pub_datetime = DateTime::parse_from_rfc2822(item.pub_date().unwrap()).unwrap();
+
+        // create object to hold item data
+        let mut item_data = object! {
+        title: item.title(),
+        link: item.link(),
+        pub_date: item.pub_date(),
+        pub_ts: pub_datetime.timestamp(),
+        description: item.description(),
+        // author: item.author()
+        };
+
+        // populate categories
+        let mut categories = json::JsonValue::new_array();
+
+        for category in item.categories() {
+            match categories.push(category.name()) {
+                Ok(_) => {}
+                Err(e) => {
+                    // memory overflow ? as a beginner, style puzzled by rust
+                    error!("Error pushing to items_data {}", e);
+                }
+            }
+        }
+
+        item_data["categories"] = categories;
+
+        if item.content().is_some() {
+            item_data["content"] = json::JsonValue::String(item.content().unwrap().to_string());
+        }
+
+        match items_data.push(item_data) {
+            Ok(_) => {}
+            Err(e) => {
+                // memory overflow ? as a beginner, style puzzled by rust
+                error!("Error pushing to items_data {}", e);
+            }
+        }
+    }
+
+    // attach the items to the json data root
+    data["items"] = items_data;
+
+    // output result
+    let output_string: String = if args.pretty {
+        data.pretty(4)
+    } else {
+        data.dump()
+    };
+
+    if args.output.len() > 0 {
+        let output_length = output_string.len();
+        let filename = args.output.to_string();
+        match fs::write(filename, output_string) {
+            Ok(_) => {
+                info!("saving {} characters to {}", output_length, args.output);
+            }
+            Err(e) => {
+                error!("{:?}", e);
+            }
+        }
+        Ok(())
+    } else {
+        // no file name specified, dump json to stdout
+        println!("{}", output_string);
+        Ok(())
+    }
+}