openethereum/parity/cli/usage.rs

228 lines
5.4 KiB
Rust

// Copyright 2015-2017 Parity Technologies (UK) Ltd.
// This file is part of Parity.
// Parity is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
// Parity is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU General Public License for more details.
// You should have received a copy of the GNU General Public License
// along with Parity. If not, see <http://www.gnu.org/licenses/>.
macro_rules! println_stderr(
($($arg:tt)*) => { {
let r = writeln!(&mut ::std::io::stderr(), $($arg)*);
r.expect("failed printing to stderr");
} }
);
macro_rules! otry {
($e: expr) => (
match $e {
Some(ref v) => v,
None => {
return None;
}
}
)
}
macro_rules! usage {
(
{
$(
$field_a:ident : $typ_a:ty,
)*
}
{
$(
$field:ident : $typ:ty = $default:expr, or $from_config:expr,
)*
}
{
$(
$field_s:ident : $typ_s:ty, display $default_s:expr, or $from_config_s:expr,
)*
}
) => {
use toml;
use std::{fs, io, process};
use std::io::{Read, Write};
use util::version;
use docopt::{Docopt, Error as DocoptError};
use helpers::replace_home;
#[derive(Debug)]
pub enum ArgsError {
Docopt(DocoptError),
Decode(toml::de::Error),
Config(String, io::Error),
}
impl ArgsError {
pub fn exit(self) -> ! {
match self {
ArgsError::Docopt(e) => e.exit(),
ArgsError::Decode(e) => {
println_stderr!("You might have supplied invalid parameters in config file.");
println_stderr!("{}", e);
process::exit(2)
},
ArgsError::Config(path, e) => {
println_stderr!("There was an error reading your config file at: {}", path);
println_stderr!("{}", e);
process::exit(2)
},
}
}
}
impl From<DocoptError> for ArgsError {
fn from(e: DocoptError) -> Self {
ArgsError::Docopt(e)
}
}
impl From<toml::de::Error> for ArgsError {
fn from(e: toml::de::Error) -> Self {
ArgsError::Decode(e)
}
}
#[derive(Debug, PartialEq)]
pub struct Args {
$(
pub $field_a: $typ_a,
)*
$(
pub $field: $typ,
)*
$(
pub $field_s: $typ_s,
)*
}
impl Default for Args {
fn default() -> Self {
Args {
$(
$field_a: Default::default(),
)*
$(
$field: $default.into(),
)*
$(
$field_s: Default::default(),
)*
}
}
}
#[derive(Default, Debug, PartialEq, Clone, Deserialize)]
struct RawArgs {
$(
$field_a: $typ_a,
)*
$(
$field: Option<$typ>,
)*
$(
$field_s: Option<$typ_s>,
)*
}
impl Args {
pub fn parse<S: AsRef<str>>(command: &[S]) -> Result<Self, ArgsError> {
let raw_args = RawArgs::parse(command)?;
// Skip loading config file if no_config flag is specified
if raw_args.flag_no_config {
return Ok(raw_args.into_args(Config::default()));
}
let config_file = raw_args.flag_config.clone().unwrap_or_else(|| raw_args.clone().into_args(Config::default()).flag_config);
let config_file = replace_home(&::dir::default_data_path(), &config_file);
let config = match (fs::File::open(&config_file), raw_args.flag_config.is_some()) {
// Load config file
(Ok(mut file), _) => {
println_stderr!("Loading config file from {}", &config_file);
let mut config = String::new();
file.read_to_string(&mut config).map_err(|e| ArgsError::Config(config_file, e))?;
Self::parse_config(&config)?
},
// Don't display error in case default config cannot be loaded.
(Err(_), false) => Config::default(),
// Config set from CLI (fail with error)
(Err(e), true) => {
return Err(ArgsError::Config(config_file, e));
},
};
Ok(raw_args.into_args(config))
}
#[cfg(test)]
pub fn parse_without_config<S: AsRef<str>>(command: &[S]) -> Result<Self, ArgsError> {
Self::parse_with_config(command, Config::default())
}
#[cfg(test)]
fn parse_with_config<S: AsRef<str>>(command: &[S], config: Config) -> Result<Self, ArgsError> {
RawArgs::parse(command).map(|raw| raw.into_args(config)).map_err(ArgsError::Docopt)
}
fn parse_config(config: &str) -> Result<Config, ArgsError> {
Ok(toml::from_str(config)?)
}
pub fn print_version() -> String {
format!(include_str!("./version.txt"), version())
}
}
impl RawArgs {
fn into_args(self, config: Config) -> Args {
let mut args = Args::default();
$(
args.$field_a = self.$field_a;
)*
$(
args.$field = self.$field.or_else(|| $from_config(&config)).unwrap_or_else(|| $default.into());
)*
$(
args.$field_s = self.$field_s.or_else(|| $from_config_s(&config)).unwrap_or(None);
)*
args
}
pub fn parse<S: AsRef<str>>(command: &[S]) -> Result<Self, DocoptError> {
Docopt::new(Self::usage()).and_then(|d| d.argv(command).deserialize())
}
fn usage() -> String {
format!(
include_str!("./usage.txt"),
$(
$field={ let v: $typ = $default.into(); v },
// Uncomment this to debug
// "named argument never used" error
// $field = $default,
)*
$(
$field_s = $default_s,
)*
)
}
}
};
}