imag/libimagrt/src/configuration.rs

278 lines
9 KiB
Rust

//
// imag - the personal information management suite for the commandline
// Copyright (C) 2015, 2016 Matthias Beyer <mail@beyermatthias.de> and contributors
//
// This library is free software; you can redistribute it and/or
// modify it under the terms of the GNU Lesser General Public
// License as published by the Free Software Foundation; version
// 2.1 of the License.
//
// This library 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
// Lesser General Public License for more details.
//
// You should have received a copy of the GNU Lesser General Public
// License along with this library; if not, write to the Free Software
// Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
//
use std::path::PathBuf;
use std::result::Result as RResult;
use std::ops::Deref;
use toml::{Parser, Value};
generate_error_module!(
generate_error_types!(ConfigError, ConfigErrorKind,
NoConfigFileFound => "No config file found",
ConfigOverrideError => "Config override error",
ConfigOverrideKeyNotAvailable => "Key not available",
ConfigOverrideTypeNotMatching => "Configuration Type not matching"
);
);
use self::error::{ConfigError, ConfigErrorKind};
/**
* Result type of this module. Either `T` or `ConfigError`
*/
pub type Result<T> = RResult<T, ConfigError>;
/// `Configuration` object
///
/// Holds all config variables which are globally available plus the configuration object from the
/// config parser, which can be accessed.
#[derive(Debug)]
pub struct Configuration {
/// The plain configuration object for direct access if necessary
config: Value,
/// The verbosity the program should run with
verbosity: bool,
/// The editor which should be used
editor: Option<String>,
///The options the editor should get when opening some file
editor_opts: String,
}
impl Configuration {
/// Get a new configuration object.
///
/// The passed runtimepath is used for searching the configuration file, whereas several file
/// names are tested. If that does not work, the home directory and the XDG basedir are tested
/// with all variants.
///
/// If that doesn't work either, an error is returned.
pub fn new(rtp: &PathBuf) -> Result<Configuration> {
fetch_config(&rtp).map(|cfg| {
let verbosity = get_verbosity(&cfg);
let editor = get_editor(&cfg);
let editor_opts = get_editor_opts(&cfg);
debug!("Building configuration");
debug!(" - verbosity : {:?}", verbosity);
debug!(" - editor : {:?}", editor);
debug!(" - editor-opts: {}", editor_opts);
Configuration {
config: cfg,
verbosity: verbosity,
editor: editor,
editor_opts: editor_opts,
}
})
}
pub fn editor(&self) -> Option<&String> {
self.editor.as_ref()
}
#[allow(dead_code)] // Why do I actually need this annotation on a pub function?
pub fn config(&self) -> &Value {
&self.config
}
pub fn store_config(&self) -> Option<&Value> {
match self.config {
Value::Table(ref tabl) => tabl.get("store"),
_ => None,
}
}
/// Override the configuration.
/// The `v` parameter is expected to contain 'key=value' pairs where the key is a path in the
/// TOML tree, the value to be an appropriate value.
///
/// The override fails if the configuration which is about to be overridden does not exist or
/// the `value` part cannot be converted to the type of the configuration value.
///
/// If `v` is empty, this is considered to be a successful `override_config()` call.
pub fn override_config(&mut self, v: Vec<String>) -> Result<()> {
use libimagutil::key_value_split::*;
use libimagutil::iter::*;
use self::error::ConfigErrorKind as CEK;
use libimagerror::into::IntoError;
v.into_iter()
.map(|s| { debug!("Trying to process '{}'", s); s })
.filter_map(|s| {
match s.into_kv() {
Some(kv) => Some(kv.into()),
None => {
warn!("Could split at '=' - will be ignore override");
None
}
}
})
.map(|(k, v)| {
match self.config.lookup_mut(&k[..]) {
Some(value) => {
match into_value(value, v) {
Some(v) => {
*value = v;
info!("Successfully overridden: {} = {}", k, value);
Ok(())
},
None => Err(CEK::ConfigOverrideTypeNotMatching.into_error()),
}
},
None => Err(CEK::ConfigOverrideKeyNotAvailable.into_error()),
}
})
.fold_defresult(|i| i)
.map_err(Box::new)
.map_err(|e| CEK::ConfigOverrideError.into_error_with_cause(e))
}
}
/// Tries to convert the String `s` into the same type as `value`.
///
/// Returns None if string cannot be converted.
///
/// Arrays and Tables are not supported and will yield `None`.
fn into_value(value: &Value, s: String) -> Option<Value> {
use std::str::FromStr;
match value {
&Value::String(_) => Some(Value::String(s)),
&Value::Integer(_) => FromStr::from_str(&s[..]).ok().map(|i| Value::Integer(i)),
&Value::Float(_) => FromStr::from_str(&s[..]).ok().map(|f| Value::Float(f)),
&Value::Boolean(_) => {
if s == "true" { Some(Value::Boolean(true)) }
else if s == "false" { Some(Value::Boolean(false)) }
else { None }
}
&Value::Datetime(_) => Some(Value::Datetime(s)),
_ => None,
}
}
impl Deref for Configuration {
type Target = Value;
fn deref(&self) -> &Value {
&self.config
}
}
fn get_verbosity(v: &Value) -> bool {
match *v {
Value::Table(ref t) => t.get("verbose")
.map_or(false, |v| match *v { Value::Boolean(b) => b, _ => false, }),
_ => false,
}
}
fn get_editor(v: &Value) -> Option<String> {
match *v {
Value::Table(ref t) => t.get("editor")
.and_then(|v| match *v { Value::String(ref s) => Some(s.clone()), _ => None, }),
_ => None,
}
}
fn get_editor_opts(v: &Value) -> String {
match *v {
Value::Table(ref t) => t.get("editor-opts")
.and_then(|v| match *v { Value::String(ref s) => Some(s.clone()), _ => None, })
.unwrap_or_default(),
_ => String::new(),
}
}
/**
* Helper to fetch the config file
*
* Tests several variants for the config file path and uses the first one which works.
*/
fn fetch_config(rtp: &PathBuf) -> Result<Value> {
use std::env;
use std::fs::File;
use std::io::Read;
use std::io::Write;
use std::io::stderr;
use xdg_basedir;
use itertools::Itertools;
use libimagutil::variants::generate_variants as gen_vars;
let variants = vec!["config", "config.toml", "imagrc", "imagrc.toml"];
let modifier = |base: &PathBuf, v: &'static str| {
let mut base = base.clone();
base.push(String::from(v));
base
};
vec![
vec![rtp.clone()],
gen_vars(rtp.clone(), variants.clone(), &modifier),
env::var("HOME").map(|home| gen_vars(PathBuf::from(home), variants.clone(), &modifier))
.unwrap_or(vec![]),
xdg_basedir::get_data_home().map(|data_dir| gen_vars(data_dir, variants.clone(), &modifier))
.unwrap_or(vec![]),
].iter()
.flatten()
.filter(|path| path.exists() && path.is_file())
.map(|path| {
let content = {
let mut s = String::new();
let f = File::open(path);
if f.is_err() {
return None
}
let mut f = f.unwrap();
f.read_to_string(&mut s).ok();
s
};
let mut parser = Parser::new(&content[..]);
let res = parser.parse();
if res.is_none() {
write!(stderr(), "Config file parser error:").ok();
for error in parser.errors {
write!(stderr(), "At [{}][{}] <> {}", error.lo, error.hi, error).ok();
write!(stderr(), "in: '{}'", &content[error.lo..error.hi]).ok();
}
None
} else {
res
}
})
.filter(|loaded| loaded.is_some())
.nth(0)
.map(|inner| Value::Table(inner.unwrap()))
.ok_or(ConfigErrorKind::NoConfigFileFound.into())
}