1
  2
  3
  4
  5
  6
  7
  8
  9
 10
 11
 12
 13
 14
 15
 16
 17
 18
 19
 20
 21
 22
 23
 24
 25
 26
 27
 28
 29
 30
 31
 32
 33
 34
 35
 36
 37
 38
 39
 40
 41
 42
 43
 44
 45
 46
 47
 48
 49
 50
 51
 52
 53
 54
 55
 56
 57
 58
 59
 60
 61
 62
 63
 64
 65
 66
 67
 68
 69
 70
 71
 72
 73
 74
 75
 76
 77
 78
 79
 80
 81
 82
 83
 84
 85
 86
 87
 88
 89
 90
 91
 92
 93
 94
 95
 96
 97
 98
 99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178

//! This crate is a library for generating structs based on a config file at build time.
//! It is intended for use in a `build.rs` file so should be included in your
//! `[build-dependencies]`.
//!
//! The core library is agnostic to the markup language of the config, but there are a few
//! features included to make it easier to use with a few markup languages:
//!
//! 1.  `json-parsing`
//! 2.  `ron-parsing`
//! 3.  `toml-parsing`
//! 4.  `yaml-parsing`
//!
//! None of these are included by default, so be sure to include one in your `Cargo.toml`.
//!
//! # Examples
//!
//! ```rust,ignore
//! // build.rs
//! extern crate config_struct;
//!
//! use config_struct::toml_parsing;
//!
//! fn main() {
//!     let toml_config = toml_parsing::parse_config_from_file("config.toml").unwrap();
//!
//!     config_struct::write_config_module(
//!         "src/config.rs",
//!         &toml_config,
//!         &Default::default()).unwrap();
//! }
//! ```
//!
//! The above build script will take the following `config.toml` file and generate `config.rs`:
//!
//! ```toml
//! // config.toml
//! name = "Application"
//! version = 5
//! features = [
//!     "one",
//!     "two",
//!     "three"
//! ]
//! ```
//!
//! ```rust,ignore
//! // config.rs
//! use std::borrow::Cow;
//!
//! #[derive(Debug, Clone, Serialize, Deserialize)]
//! #[allow(non_camel_case_types)]
//! pub struct Config {
//!     pub features: Cow<'static, [Cow<'static, str>]>,
//!     pub name: Cow<'static, str>,
//!     pub version: i64,
//! }
//!
//! pub const CONFIG: Config = Config {
//!     features: Cow::Borrowed(&[Cow::Borrowed("one"), Cow::Borrowed("two"), Cow::Borrowed("three")]),
//!     name: Cow::Borrowed("Application"),
//!     version: 5,
//! };
//! ```
//!
//! Strings and arrays are represented by `Cow` types, which allows the entire Config struct to
//! be either heap allocated at runtime, or a compile time constant, as shown above.


#[cfg(feature = "json-parsing")]
extern crate serde_json;

#[cfg(feature = "ron-parsing")]
extern crate ron;

#[cfg(feature = "toml-parsing")]
extern crate toml;

#[cfg(feature = "yaml-parsing")]
extern crate serde_yaml;


#[cfg(feature = "json-parsing")]
pub mod json_parsing;

#[cfg(feature = "ron-parsing")]
pub mod ron_parsing;

#[cfg(feature = "toml-parsing")]
pub mod toml_parsing;

#[cfg(feature = "yaml-parsing")]
pub mod yaml_parsing;


#[macro_use]
extern crate failure;


#[cfg(any(feature = "json-parsing", feature = "ron-parsing", feature = "toml-parsing", feature = "yaml-parsing"))]
mod parsing;

mod generation;
mod options;
mod validation;
mod value;


use std::path::Path;

use failure::Error;

pub use options::{ Options };
pub use validation::StructGenerationError;
pub use value::{ RawValue, RawStructValue };


/// Generate Rust code for a RawStructValue.
///
/// This will recursively generate code for all nested structs within the given value.
///
/// The easiest way to get a RawStructValue is to use the `parse_config` or
/// `parse_config_from_file` function from one of the parsing modules.
pub fn create_config_module(
    raw_config: &RawStructValue,
    options: &Options) -> Result<String, StructGenerationError>
{
    validation::validate_options(options)?;

    let raw_config = {
        // TODO: Ugh, this is really ugly
        let mut config = raw_config.clone();
        config.struct_name = options.struct_name.clone();
        config
    };

    validation::validate_struct_value(&raw_config)?;

    let mut code = String::new();

    code.push_str("use std::borrow::Cow;\n\n");

    let structs = generation::generate_structs(&raw_config, options);
    code.push_str(&structs);

    let const_name = options.const_name.clone().unwrap_or(options.struct_name.to_uppercase());

    code.push_str(
        &format!(
            "pub const {}: {} = {};\n",
            const_name,
            options.struct_name,
            generation::struct_value_string(&raw_config, 0)));

    Ok(code)
}


/// Generate Rust code for a RawStructValue and write it to a file.
///
/// This simply writes the result of `create_config_module` to a file.
pub fn write_config_module<P>(
    module_path: P,
    raw_config: &RawStructValue,
    options: &Options) -> Result<(), Error>
where
    P: AsRef<Path>
{
    use std::fs::File;
    use std::io::Write;

    let code = create_config_module(raw_config, options)?;

    let file = &mut File::create(module_path)?;
    file.write_all(code.as_bytes())?;

    Ok(())
}