feat: Added Gura support

Cargo.toml

@@ -15,11 +15,12 @@ edition = "2018"
 maintenance = { status = "actively-developed" }
 
 [features]
-default = ["toml", "json", "yaml", "ini", "ron", "json5", "convert-case", "async"]
+default = ["toml", "json", "yaml", "ini", "ron", "json5", "gura", "convert-case", "async"]
 json = ["serde_json"]
 yaml = ["yaml-rust"]
 ini = ["rust-ini"]
 json5 = ["json5_rs", "serde/derive"]
+gura = ["serde_gura"]
 convert-case = ["convert_case"]
 preserve_order = ["indexmap", "toml?/preserve_order", "serde_json?/preserve_order", "ron?/indexmap"]
 async = ["async-trait"]
@@ -36,6 +37,7 @@ yaml-rust = { version = "0.4", optional = true }
 rust-ini = { version = "0.19", optional = true }
 ron = { version = "0.8", optional = true }
 json5_rs = { version = "0.4", optional = true, package = "json5" }
+serde_gura = { version = "0.1", optional = true }
 indexmap = { version = "2.0.0", features = ["serde"], optional = true }
 convert_case = { version = "0.6", optional = true }
 pathdiff = "0.2"

README.md

@@ -11,7 +11,7 @@
 
  - Set defaults
  - Set explicit values (to programmatically override)
- - Read from [JSON], [TOML], [YAML], [INI], [RON], [JSON5] files
+ - Read from [JSON], [TOML], [YAML], [INI], [RON], [JSON5], [GURA] files
  - Read from environment
  - Loosely typed — Configuration values may be read in any supported type, as long as there exists a reasonable conversion
  - Access nested fields using a formatted path — Uses a subset of JSONPath; currently supports the child ( `redis.port` ) and subscript operators ( `databases[0].name` )
@@ -22,6 +22,7 @@
 [INI]: https://github.com/zonyitoo/rust-ini
 [RON]: https://github.com/ron-rs/ron
 [JSON5]: https://github.com/callum-oakley/json5-rs
+[GURA]: https://github.com/gura-conf/gura-rs-parser
 
 Please note this library
 
@@ -43,6 +44,7 @@ config = "0.13.1"
  - `toml` - Adds support for reading TOML files
  - `ron` - Adds support for reading RON files
  - `json5` - Adds support for reading JSON5 files
+ - `gura` - Adds support for reading GURA files
 
 ### Support for custom formats
 

src/file/format/gura.rs

@@ -0,0 +1,14 @@
+use std::error::Error;
+
+use crate::format;
+use crate::map::Map;
+use crate::value::Value;
+
+pub fn parse(
+    uri: Option<&String>,
+    text: &str,
+) -> Result<Map<String, Value>, Box<dyn Error + Send + Sync>> {
+    // Parse a Gura input from the provided text
+    let value = format::from_parsed_value(uri, serde_gura::from_str(text)?);
+    format::extract_root_table(uri, value)
+}

src/file/format/mod.rs

@@ -27,6 +27,9 @@ mod ron;
 #[cfg(feature = "json5")]
 mod json5;
 
+#[cfg(feature = "gura")]
+mod gura;
+
 /// File formats provided by the library.
 ///
 /// Although it is possible to define custom formats using [`Format`] trait it is recommended to use FileFormat if possible.
@@ -55,6 +58,10 @@ pub enum FileFormat {
     /// JSON5 (parsed with json5)
     #[cfg(feature = "json5")]
     Json5,
+
+    /// GURA (parsed with serde_gura)
+    #[cfg(feature = "gura")]
+    Gura,
 }
 
 lazy_static! {
@@ -81,6 +88,9 @@ lazy_static! {
         #[cfg(feature = "json5")]
         formats.insert(FileFormat::Json5, vec!["json5"]);
 
+        #[cfg(feature = "gura")]
+        formats.insert(FileFormat::Gura, vec!["ura"]);
+
         formats
     };
 }
@@ -117,13 +127,17 @@ impl FileFormat {
             #[cfg(feature = "json5")]
             FileFormat::Json5 => json5::parse(uri, text),
 
+            #[cfg(feature = "gura")]
+            FileFormat::Gura => gura::parse(uri, text),
+
             #[cfg(all(
                 not(feature = "toml"),
                 not(feature = "json"),
                 not(feature = "yaml"),
                 not(feature = "ini"),
                 not(feature = "ron"),
                 not(feature = "json5"),
+                not(feature = "gura"),
             ))]
             _ => unreachable!("No features are enabled, this library won't work without features"),
         }

src/lib.rs

@@ -6,7 +6,7 @@
 //!  - Environment variables
 //!  - String literals in well-known formats
 //!  - Another Config instance
-//!  - Files: TOML, JSON, YAML, INI, RON, JSON5 and custom ones defined with Format trait
+//!  - Files: TOML, JSON, YAML, INI, RON, JSON5, GURA and custom ones defined with Format trait
 //!  - Manual, programmatic override (via a `.set` method on the Config instance)
 //!
 //! Additionally, Config supports:

tests/Settings-enum-test.ura

@@ -0,0 +1,3 @@
+# comment
+
+bar: "bar is a lowercase param"

tests/Settings.ura

@@ -0,0 +1,20 @@
+#comment
+
+debug: true
+debug_gura: true
+production: false
+arr: [1, 2, 3, 4, 5, 6, 7, 8, 9, 10]
+place:
+    name: "Torre di Pisa"
+    longitude: 43.7224985
+    latitude: 10.3970522
+    favorite: false
+    reviews: 3866
+    rating: 4.5
+    creator:
+        name: "John Smith"
+        username: "jsmith"
+        email: "jsmith@localhost"
+
+FOO: "FOO should be overridden"
+bar: "I am bar"

tests/file_gura.rs

@@ -0,0 +1,199 @@
+#![cfg(feature = "gura")]
+
+use serde_derive::Deserialize;
+
+use config::{Config, File, FileFormat, Map, Value};
+use float_cmp::ApproxEqUlps;
+
+#[derive(Debug, Deserialize)]
+struct Place {
+    name: String,
+    longitude: f64,
+    latitude: f64,
+    favorite: bool,
+    telephone: Option<String>,
+    reviews: u64,
+    creator: Map<String, Value>,
+    rating: Option<f32>,
+}
+
+#[derive(Debug, Deserialize)]
+struct Settings {
+    debug: f64,
+    production: Option<String>,
+    place: Place,
+    #[serde(rename = "arr")]
+    elements: Vec<String>,
+}
+
+fn make() -> Config {
+    Config::builder()
+        .add_source(File::new("tests/Settings", FileFormat::Gura))
+        .build()
+        .unwrap()
+}
+
+#[test]
+fn test_file() {
+    let c = make();
+
+    // Deserialize the entire file as single struct
+    let s: Settings = c.try_deserialize().unwrap();
+
+    assert!(s.debug.approx_eq_ulps(&1.0, 2));
+    assert_eq!(s.production, Some("false".to_string()));
+    assert_eq!(s.place.name, "Torre di Pisa");
+    assert!(s.place.longitude.approx_eq_ulps(&43.722_498_5, 2));
+    assert!(s.place.latitude.approx_eq_ulps(&10.397_052_2, 2));
+    assert!(!s.place.favorite);
+    assert_eq!(s.place.reviews, 3866);
+    assert_eq!(s.place.rating, Some(4.5));
+    assert_eq!(s.place.telephone, None);
+    assert_eq!(s.elements.len(), 10);
+    assert_eq!(s.elements[3], "4".to_string());
+    if cfg!(feature = "preserve_order") {
+        assert_eq!(
+            s.place
+                .creator
+                .into_iter()
+                .collect::<Vec<(String, config::Value)>>(),
+            vec![
+                ("name".to_string(), "John Smith".into()),
+                ("username".into(), "jsmith".into()),
+                ("email".into(), "jsmith@localhost".into()),
+            ]
+        );
+    } else {
+        assert_eq!(
+            s.place.creator["name"].clone().into_string().unwrap(),
+            "John Smith".to_string()
+        );
+    }
+}
+
+#[test]
+fn test_gura_vec() {
+    let c = Config::builder()
+        .add_source(File::from_str(
+            r#"
+            hosts: [
+                "alpha",
+                "omega"
+            ]
+            "#,
+            FileFormat::Gura,
+        ))
+        .build()
+        .unwrap();
+
+    let v = c.get_array("hosts").unwrap();
+    let mut vi = v.into_iter();
+    assert_eq!(vi.next().unwrap().into_string().unwrap(), "alpha");
+    assert_eq!(vi.next().unwrap().into_string().unwrap(), "omega");
+    assert!(vi.next().is_none());
+}
+
+#[derive(Debug, Deserialize, PartialEq)]
+enum EnumSettings {
+    Bar(String),
+}
+
+#[derive(Debug, Deserialize, PartialEq)]
+struct StructSettings {
+    foo: String,
+    bar: String,
+}
+#[derive(Debug, Deserialize, PartialEq)]
+#[allow(non_snake_case)]
+struct CapSettings {
+    FOO: String,
+}
+
+#[test]
+fn test_override_uppercase_value_for_struct() {
+    std::env::set_var("APP_FOO", "I HAVE BEEN OVERRIDDEN_WITH_UPPER_CASE");
+
+    let cfg = Config::builder()
+        .add_source(File::new("tests/Settings", FileFormat::Gura))
+        .add_source(config::Environment::with_prefix("APP").separator("_"))
+        .build()
+        .unwrap();
+
+    let cap_settings = cfg.clone().try_deserialize::<CapSettings>();
+    let lower_settings = cfg.try_deserialize::<StructSettings>().unwrap();
+
+    match cap_settings {
+        Ok(v) => {
+            // this assertion will ensure that the map has only lowercase keys
+            assert_ne!(v.FOO, "FOO should be overridden");
+            assert_eq!(
+                lower_settings.foo,
+                "I HAVE BEEN OVERRIDDEN_WITH_UPPER_CASE".to_string()
+            );
+        }
+        Err(e) => {
+            if e.to_string().contains("missing field `FOO`") {
+                println!("triggered error {:?}", e);
+                assert_eq!(
+                    lower_settings.foo,
+                    "I HAVE BEEN OVERRIDDEN_WITH_UPPER_CASE".to_string()
+                );
+            } else {
+                panic!("{}", e);
+            }
+        }
+    }
+}
+
+#[test]
+fn test_override_lowercase_value_for_struct() {
+    std::env::set_var("config_foo", "I have been overridden_with_lower_case");
+
+    let cfg = Config::builder()
+        .add_source(File::new("tests/Settings", FileFormat::Gura))
+        .add_source(config::Environment::with_prefix("config").separator("_"))
+        .build()
+        .unwrap();
+
+    let values: StructSettings = cfg.try_deserialize().unwrap();
+    assert_eq!(
+        values.foo,
+        "I have been overridden_with_lower_case".to_string()
+    );
+    assert_ne!(values.foo, "I am bar".to_string());
+}
+
+#[test]
+fn test_override_uppercase_value_for_enums() {
+    std::env::set_var("APPS_BAR", "I HAVE BEEN OVERRIDDEN_WITH_UPPER_CASE");
+
+    let cfg = Config::builder()
+        .add_source(File::new("tests/Settings-enum-test", FileFormat::Gura))
+        .add_source(config::Environment::with_prefix("APPS").separator("_"))
+        .build()
+        .unwrap();
+    let val: EnumSettings = cfg.try_deserialize().unwrap();
+
+    assert_eq!(
+        val,
+        EnumSettings::Bar("I HAVE BEEN OVERRIDDEN_WITH_UPPER_CASE".to_string())
+    );
+}
+
+#[test]
+fn test_override_lowercase_value_for_enums() {
+    std::env::set_var("test_bar", "I have been overridden_with_lower_case");
+
+    let cfg = Config::builder()
+        .add_source(File::new("tests/Settings-enum-test", FileFormat::Gura))
+        .add_source(config::Environment::with_prefix("test").separator("_"))
+        .build()
+        .unwrap();
+
+    let param: EnumSettings = cfg.try_deserialize().unwrap();
+
+    assert_eq!(
+        param,
+        EnumSettings::Bar("I have been overridden_with_lower_case".to_string())
+    );
+}