Merge pull request #2 from marcoradocchia/1-read-from-stdin

Added feature closing #1

CHANGELOG.md

@@ -1,11 +1,18 @@
 # Changelog
 
-## [unreleased]
+## [0.2.0] - 2022-07-18
 
 ### Added
 
+- Feature to read string to encode from standard input, which allows to pipe
+  commands to `qr-rs` (closing issue #1).
 - `border` CLI option to specify border size.
-- `error-correction-level` CLI option to specify QR *error-correction-level*.
+- `error-correction-level` CLI option to specify QR *error-correction-level* as
+  one of the following values:
+  - **low**;
+  - **medium**;
+  - **quartile**;
+  - **high**.
 
 ## [0.1.0] - 2022-07-15
 

Cargo.toml

@@ -1,10 +1,10 @@
 [package]
 name = "qr-rs"
-version = "0.1.0"
+version = "0.2.0"
 authors = ["Marco Radocchia <[email protected]"]
 edition = "2021"
 rust-version = "1.62.0"
-description = "Encode URLs or text into QR codes."
+description = "A CLI utility to encode URLs or text into QR codes in various formats and colors."
 readme = "README.md"
 repository = "https://github.com/marcoradocchia/qr-rs"
 license = "GPL-3.0-only"

docs/README.md

@@ -73,25 +73,44 @@ paru -S qr-rs-bin
 [^1]: Currently only `x86_64`
 
 ## Usage
+
 ```
-qr-rs 0.1.0
+qr-rs 0.2.0
 Marco Radocchia <[email protected]>
-Encode URLs or text into QR codes.
+A CLI utility to encode URLs or text into QR codes in various formats and colors.
 
 USAGE:
-    qr [OPTIONS] <STRING>
+    qr [OPTIONS] [STRING]
 
 ARGS:
     <STRING>    String to encode
 
 OPTIONS:
-    -b, --bg <BG>            Foreground color (hex code) [default: #FFF]
-    -f, --fg <FG>            Background color (hex code) [default: #000]
-    -h, --help               Print help information
-    -o, --output <OUTPUT>    Output file (supported file extensions: jpeg, jpg, png, svg); omit to
-                             print QR code to console
-    -s, --scale <SCALE>      Scale factor (raster image output only) [default: 25]
-    -V, --version            Print version information
+    -b, --bg <BG>
+            Foreground color (hex code) [default: #FFF]
+
+    -B, --border <BORDER>
+            Border size (expressed in unit blocks) [default: 1]
+
+        --error-correction-level <ERROR_CORRECTION_LEVEL>
+            QR error orrection level [default: medium] [possible values: low, medium, quartile,
+            high]
+
+    -f, --fg <FG>
+            Background color (hex code) [default: #000]
+
+    -h, --help
+            Print help information
+
+    -o, --output <OUTPUT>
+            Output file (supported file extensions: jpeg, jpg, png, svg); omit to print QR code to
+            console
+
+    -s, --scale <SCALE>
+            Scale factor (raster image output only) [default: 25]
+
+    -V, --version
+            Print version information
 ```
 
 ## Changelog

src/args.rs

@@ -19,7 +19,7 @@ pub use clap::Parser;
 use qrcodegen::QrCodeEcc;
 use std::path::PathBuf;
 
-/// Encode URLs or text into QR codes.
+/// A CLI utility to encode URLs or text into QR codes in various formats and colors.
 #[derive(Parser, Debug)]
 #[clap(
     author = "Marco Radocchia <[email protected]>",
@@ -72,5 +72,5 @@ pub struct Args {
 
     /// String to encode.
     #[clap(value_parser)]
-    pub string: String,
+    pub string: Option<String>,
 }

src/main.rs

@@ -23,7 +23,13 @@ use dialoguer::{theme::ColorfulTheme, Confirm};
 use error::{Error, ErrorKind, Warning};
 use image::{ImageBuffer, RgbImage};
 use qrcodegen::QrCode;
-use std::{fmt::Write as _, fs, io::Write, path::Path, process};
+use std::{
+    fmt::Write as _,
+    fs,
+    io::{self, Read, Write},
+    path::Path,
+    process,
+};
 use utils::hex_to_rgb;
 
 /// QR code.
@@ -42,7 +48,7 @@ impl Qr {
     fn new(data: QrCode, border: u8) -> Self {
         Self {
             data,
-            border: border.into()
+            border: border.into(),
         }
     }
 }
@@ -144,20 +150,45 @@ impl QrOutput for Qr {
         Ok(())
     }
 
+    /// Print QR code to standard output.
     fn console(&self) {
         for y in -self.border..self.data.size() + self.border {
             for x in -self.border..self.data.size() + self.border {
-                print!("{0}{0}", if self.data.get_module(x, y) { '█' } else { ' ' });
+                print!(
+                    "{0}{0}",
+                    if self.data.get_module(x, y) {
+                        '█'
+                    } else {
+                        ' '
+                    }
+                );
             }
             println!();
         }
     }
 }
 
 /// Runs the program & catches errors.
-fn run(args: &Args) -> Result<(), ErrorKind> {
+fn run(args: Args) -> Result<(), ErrorKind> {
+    // If string to encode is not passed in as CLI argument, check stdin for piped string.
+    let string = args.string.unwrap_or_else(|| {
+        if atty::is(atty::Stream::Stdin) {
+            clap::Command::new("qr [OPTIONS] [STRING]")
+                .error(
+                    clap::ErrorKind::MissingRequiredArgument,
+                    "Missing input string.\n\n\
+                        \tEither provide it as a CLI argument or pipe it in from standard input.",
+                )
+                .exit();
+        } else {
+            let mut string = String::new();
+            io::stdin().lock().read_to_string(&mut string).unwrap();
+            string.trim_end().to_string()
+        }
+    });
+
     // Generate QR code.
-    let qr = match QrCode::encode_text(&args.string, args.error_correction_level) {
+    let qr = match QrCode::encode_text(&string, args.error_correction_level) {
         Ok(data) => Qr::new(data, args.border),
         Err(err) => return Err(ErrorKind::Error(Error::QrCodeErr(err.to_string()))),
     };
@@ -200,7 +231,7 @@ fn run(args: &Args) -> Result<(), ErrorKind> {
 
 /// Main function: calls run function and prints errors.
 fn main() {
-    if let Err(e) = run(&Args::parse()) {
+    if let Err(e) = run(Args::parse()) {
         e.colorize().unwrap();
         process::exit(1);
     }

src/utils.rs

@@ -41,7 +41,11 @@ pub fn parse_error_correction_level(ecl: &str) -> Result<QrCodeEcc, String> {
     })
 }
 
-/// This conversion assumes the HEX string as valid color and returns corresponding RGB value.
+/// Convert HEX color code to RGB values
+///
+/// # Note
+///
+/// This function assumes `hex` parameter being a valid HEX color code.
 pub fn hex_to_rgb(hex: &str) -> [u8; 3] {
     let mut hex = hex.strip_prefix('#').unwrap().to_string();
     if hex.len() == 3 {