polybar/include/components/config.hpp

231 lines
6.2 KiB
C++

#pragma once
#include <boost/lexical_cast.hpp>
#include <boost/property_tree/ini_parser.hpp>
#include <boost/property_tree/ptree.hpp>
#include "common.hpp"
#include "components/logger.hpp"
#include "utils/file.hpp"
#include "utils/string.hpp"
LEMONBUDDY_NS
using ptree = boost::property_tree::ptree;
DEFINE_ERROR(value_error);
DEFINE_ERROR(key_error);
class config {
public:
/**
* Construct config
*/
explicit config(const logger& logger) : m_logger(logger) {}
/**
* Load configuration and validate bar section
*
* This is done outside the constructor due to boost::di noexcept
*/
void load(string file, string barname) {
m_file = file;
m_current_bar = barname;
if (!file_util::exists(file))
throw application_error("Could not find config file: " + file);
try {
boost::property_tree::read_ini(file, m_ptree);
} catch (const std::exception& e) {
throw application_error(e.what());
}
auto bars = defined_bars();
if (std::find(bars.begin(), bars.end(), m_current_bar) == bars.end())
throw application_error("Undefined bar: " + m_current_bar);
if (has_env("XDG_CONFIG_HOME"))
file = string_util::replace(file, read_env("XDG_CONFIG_HOME"), "$XDG_CONFIG_HOME");
if (has_env("HOME"))
file = string_util::replace(file, read_env("HOME"), "~");
m_logger.trace("config: Loaded %s", file);
m_logger.trace("config: Current bar section: [%s]", bar_section());
}
/**
* Get path of loaded file
*/
string filepath() const {
return m_file;
}
/**
* Get the section name of the bar in use
*/
string bar_section() const {
return "bar/" + m_current_bar;
}
/**
* Get a list of defined bar sections in the current config
*/
vector<string> defined_bars() const {
vector<string> bars;
for (auto&& p : m_ptree) {
if (p.first.compare(0, 4, "bar/") == 0)
bars.emplace_back(p.first.substr(4));
}
return bars;
}
/**
* Build path used to find a parameter in the given section
*/
string build_path(const string& section, const string& key) const {
return section + "." + key;
}
/**
* Get parameter for the current bar by name
*/
template <typename T>
T get(string key) const {
return get<T>(bar_section(), key);
}
/**
* Get value of a variable by section and parameter name
*/
template <typename T>
T get(string section, string key) const {
auto val = m_ptree.get_optional<T>(build_path(section, key));
if (val == boost::none)
throw key_error("Missing property '" + key + "' in section [" + section + "]");
auto str_val = m_ptree.get<string>(build_path(section, key));
return dereference_var<T>(section, key, str_val, val.get());
}
/**
* Get value of a variable by section and parameter name
* with a default value in case the parameter isn't defined
*/
template <typename T>
T get(string section, string key, T default_value) const {
auto val = m_ptree.get_optional<T>(build_path(section, key));
auto str_val = m_ptree.get_optional<string>(build_path(section, key));
return dereference_var<T>(
section, key, str_val.get_value_or(""), val.get_value_or(default_value));
}
/**
* Get list of values for the current bar by name
*/
template <typename T>
T get_list(string key) const {
return get_list<T>(bar_section(), key);
}
/**
* Get list of values by section and parameter name
*/
template <typename T>
vector<T> get_list(string section, string key) const {
vector<T> vec;
optional<T> value;
while ((value = m_ptree.get_optional<T>(
build_path(section, key) + "-" + to_string(vec.size()))) != boost::none) {
auto str_val = m_ptree.get<string>(build_path(section, key) + "-" + to_string(vec.size()));
vec.emplace_back(dereference_var<T>(section, key, str_val, value.get()));
}
if (vec.empty())
throw key_error("Missing property '" + key + "-0' in section [" + section + "]");
return vec;
}
/**
* Get list of values by section and parameter name
* with a default list in case the list isn't defined
*/
template <typename T>
vector<T> get_list(string section, string key, vector<T> default_value) const {
vector<T> vec;
optional<T> value;
while ((value = m_ptree.get_optional<T>(
build_path(section, key) + "-" + to_string(vec.size()))) != boost::none) {
auto str_val = m_ptree.get<string>(build_path(section, key) + "-" + to_string(vec.size()));
vec.emplace_back(dereference_var<T>(section, key, str_val, value.get()));
}
if (vec.empty())
return default_value;
else
return vec;
}
/**
* Configure injection module
*/
template <typename T = const config&>
static di::injector<T> configure() {
return di::make_injector(logger::configure());
}
protected:
/**
* Find value of a config parameter defined as a reference
* variable using ${section.param} or ${env:VAR}
*/
template <typename T>
T dereference_var(string ref_section, string ref_key, string var, const T ref_val) const {
auto n = var.find("${");
auto m = var.find("}");
if (n != 0 || m != var.length() - 1)
return ref_val;
auto path = var.substr(2, m - 2);
if (path.find("env:") == 0) {
if (has_env(path.substr(4).c_str()))
return boost::lexical_cast<T>(read_env(path.substr(4).c_str()));
return ref_val;
}
auto ref_path = build_path(ref_section, ref_key);
if ((n = path.find(".")) == string::npos)
throw value_error("Invalid variable " + ref_path + " => ${" + path + "}");
auto section = string_util::replace(path.substr(0, n), "BAR", bar_section());
auto key = path.substr(n + 1, path.length() - n - 1);
auto val = m_ptree.get_optional<T>(build_path(section, key));
if (val == boost::none)
throw value_error("Variable defined at [" + ref_path +
"] points to a non existing parameter: [" + build_path(section, key) + "]");
auto str_val = m_ptree.get<string>(build_path(section, key));
return dereference_var<T>(section, key, str_val, val.get());
}
private:
const logger& m_logger;
ptree m_ptree;
string m_file;
string m_current_bar;
};
LEMONBUDDY_NS_END