deps

.github/workflows/ci.yml

@@ -75,40 +75,42 @@ jobs:
       matrix:
         toolchain:
           - stable
-          - beta
+          - 1.65.0  # keep in sync with manifest MSRV
+        target:
+          - thumbv7em-none-eabihf
 
     steps:
       - uses: actions/checkout@v2
-
       - name: Install Rust ${{ matrix.toolchain }}
         uses: actions-rs/toolchain@v1
         with:
           toolchain: ${{ matrix.toolchain }}
-          target: thumbv7em-none-eabihf
+          target: ${{ matrix.target }}
           override: true
 
       - name: Cargo Check
         uses: actions-rs/cargo@v1
         with:
           command: check
-          args: --verbose
+          args: --verbose --target ${{ matrix.target }}
 
       - name: Cargo Build [No-Features]
         uses: actions-rs/cargo@v1
         with:
           command: build
-          args: --no-default-features
+          args: --no-default-features --target ${{ matrix.target }}
 
       - name: Cargo Build
         uses: actions-rs/cargo@v1
         with:
           command: build
+          args: --target ${{ matrix.target }}
 
       - name: Cargo Build [Release]
         uses: actions-rs/cargo@v1
         with:
           command: build
-          args: --release
+          args: --release --target ${{ matrix.target }}
 
       - name: Cargo Build [Examples]
         uses: actions-rs/cargo@v1
@@ -117,7 +119,17 @@ jobs:
           args: --examples
 
   test:
-    runs-on: ubuntu-20.04
+    runs-on: ubuntu-latest
+    strategy:
+      matrix:
+        toolchain:
+          - stable
+          - 1.65.0  # keep in sync with manifest MSRV
+        args:
+          - --all-features
+          - --no-default-features
+          - --no-default-features --features json
+
     steps:
       - uses: actions/checkout@v2
 
@@ -130,20 +142,22 @@ jobs:
         uses: actions-rs/toolchain@v1
         with:
           override: true
-          toolchain: stable
+          toolchain: ${{ matrix.toolchain }}
           profile: minimal
 
       - name: Cargo Test
         uses: actions-rs/cargo@v1
         with:
           command: test
+          args: ${{ matrix.args }}
 
   examples:
-    runs-on: ubuntu-20.04
+    runs-on: ubuntu-latest
     strategy:
       matrix:
         example:
           - mqtt
+          - readback
     steps:
       - uses: actions/checkout@v2
 

CHANGELOG.md

@@ -6,6 +6,10 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ## Unreleased
 
+### Added
+
+* `json` feature to enable the `Serde<JsonCoreSlash>` spec. Enabled by default.
+
 ### Changed
 
 * [breaking] The `Miniconf` trait is now generic over the `Deserializer`/`Serializer`. It
@@ -29,6 +33,9 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 * [breaking] `iter_paths`/`MiniconfIter` is now generic over the type
   to write the path into. Downstream crates should replace `iter_paths::<L, TS>()` with
   `iter_paths::<L, heapless::String<TS>>()`.
+* The `mqtt-client` feature has been renamed into `mqtt` with backward compatibility.
+* [breaking] Re-exports of `heapless` and `serde-json-core` have been removed as they are
+  not needed to work with the public API.
 
 ## [0.7.1] (https://github.com/quartiq/miniconf/compare/v0.7.0...v0.7.1)
 

Cargo.toml

@@ -1,31 +1,33 @@
 [package]
 name = "miniconf"
-
 # Don't forget to change `miniconf_derive`'s version as well.
 version = "0.7.1"
-
 authors = ["James Irwin <[email protected]>", "Ryan Summers <[email protected]", "Robert Jördens <[email protected]>"]
 edition = "2021"
 license = "MIT"
 description = "Inspect serde namespaces by path"
 repository = "https://github.com/quartiq/miniconf"
 keywords = ["settings", "serde", "no_std", "json", "mqtt"]
 categories = ["no-std", "config", "rust-patterns", "parsing"]
-rust-version = "1.65.0"
+rust-version = "1.65.0"  # keep in sync with CI
+resolver = "2"
 
 [dependencies]
-miniconf_derive = { path = "miniconf_derive" , version = "0.6" }
-serde-json-core = { git = "https://github.com/rust-embedded-community/serde-json-core.git" }
 serde = { version = "1.0.120", features = ["derive"], default-features = false }
-log = "0.4"
-heapless = { version = "0.7", features = ["serde"] }
+miniconf_derive = { path = "miniconf_derive" , version = "0.6" }
+itoa = "1.0.4"
+
+serde-json-core = { git = "https://github.com/rust-embedded-community/serde-json-core.git" , optional = true}
+log = {version = "0.4", optional = true}
+heapless = { version = "0.7", features = ["serde"], optional=true }
 minimq = { version = "0.7", optional = true }
 smlang = { version = "0.6", optional = true }
-itoa = "1.0.4"
 
 [features]
-default = ["mqtt-client"]
-mqtt-client = ["minimq", "smlang"]
+default = ["mqtt"]
+json = ["dep:serde-json-core", "dep:heapless"]
+mqtt = ["dep:minimq", "dep:smlang", "dep:log", "json"]
+mqtt-client = ["mqtt"]  # backwards compat
 
 [dev-dependencies]
 machine = "0.3"
@@ -41,3 +43,8 @@ branch = "feature/0.7"
 
 [[example]]
 name = "mqtt"
+required-features = ["mqtt"]
+
+[[example]]
+name = "readback"
+required-features = ["json"]

README.md

@@ -16,7 +16,7 @@ client](MqttClient) and a Python reference implementation to ineract with it.
 
 ## Example
 ```rust
-use miniconf::{heapless::String, Error, Miniconf, SerDe};
+use miniconf::{Error, Miniconf, SerDe};
 use serde::{Deserialize, Serialize};
 
 #[derive(Deserialize, Serialize, Copy, Clone, Default)]
@@ -97,7 +97,7 @@ let len = settings.get("/struct_", &mut buf)?;
 assert_eq!(&buf[..len], br#"{"a":3,"b":3}"#);
 
 // Iterating over and serializing all paths
-for path in Settings::iter_paths::<3, String<32>>().unwrap() {
+for path in Settings::iter_paths::<3, String>().unwrap() {
     match settings.get(&path, &mut buf) {
         Ok(len) => {
             settings.set(&path, &buf[..len]).unwrap();
@@ -110,7 +110,7 @@ for path in Settings::iter_paths::<3, String<32>>().unwrap() {
     }
 }
 
-# Ok::<(), miniconf::Error<miniconf::serde_json_core::de::Error>>(())
+# Ok::<(), miniconf::Error<serde_json_core::de::Error>>(())
 ```
 
 ## MQTT
@@ -160,4 +160,7 @@ Deferred (non-atomic) access to inner elements of some types is not yet supporte
 * Tuple structs (other than [Option], [Array])
 
 ## Features
-* `mqtt-client` Enabled the MQTT client feature. See the example in [MqttClient].
+* `mqtt` Enable the MQTT client feature. See the example in [MqttClient].
+* `json` Enable the [SerDe] implementation for the [JsonCoreSlash] style.
+
+Both features are enabled by default.

examples/readback.rs

@@ -1,4 +1,4 @@
-use miniconf::{heapless::String, Miniconf, SerDe};
+use miniconf::{Miniconf, SerDe};
 
 #[derive(Debug, Default, Miniconf)]
 struct AdditionalSettings {
@@ -23,7 +23,7 @@ fn main() {
     };
 
     // Maintains our state of iteration.
-    let mut settings_iter = Settings::iter_paths::<5, String<128>>().unwrap();
+    let mut settings_iter = Settings::iter_paths::<5, String>().unwrap();
 
     // Just get one topic/value from the iterator
     if let Some(topic) = settings_iter.next() {

miniconf_derive/Cargo.toml

@@ -13,6 +13,6 @@ categories = ["no-std", "config", "rust-patterns", "parsing"]
 proc-macro = true
 
 [dependencies]
-syn = { version="1.0.58", features=["extra-traits"] }
-quote = "1.0.8"
-proc-macro2 = "1.0.24"
+syn = { version = "2.0", features = ["extra-traits"] }
+quote = "1.0"
+proc-macro2 = "1.0"

miniconf_derive/src/field.rs

@@ -1,4 +1,3 @@
-use super::attributes::{AttributeParser, MiniconfAttribute};
 use syn::{parse_quote, Generics};
 
 pub struct StructField {
@@ -8,14 +7,21 @@ pub struct StructField {
 
 impl StructField {
     pub fn new(field: syn::Field) -> Self {
-        let attributes: Vec<MiniconfAttribute> = field
-            .attrs
-            .iter()
-            .filter(|attr| attr.path.is_ident("miniconf"))
-            .map(|attr| AttributeParser::new(attr.tokens.clone()).parse())
-            .collect();
+        let mut deferred = false;
 
-        let deferred = attributes.iter().any(|x| *x == MiniconfAttribute::Defer);
+        for attr in field.attrs.iter() {
+            if attr.path().is_ident("miniconf") {
+                attr.parse_nested_meta(|meta| {
+                    if meta.path.is_ident("defer") {
+                        deferred = true;
+                        Ok(())
+                    } else {
+                        Err(meta.error(format!("unrecognized miniconf attribute {:?}", meta.path)))
+                    }
+                })
+                .unwrap();
+            }
+        }
 
         Self { deferred, field }
     }

miniconf_derive/src/lib.rs

@@ -2,7 +2,6 @@ use proc_macro::TokenStream;
 use quote::quote;
 use syn::{parse_macro_input, DeriveInput};
 
-mod attributes;
 mod field;
 
 use field::StructField;

src/array.rs

@@ -1,4 +1,4 @@
-use super::{Error, IterError, Metadata, Miniconf};
+use crate::{Error, IterError, Metadata, Miniconf};
 use core::{
     fmt::Write,
     ops::{Deref, DerefMut},
@@ -173,7 +173,7 @@ impl<T: Miniconf, const N: usize> Miniconf for Array<T, N> {
     }
 }
 
-impl<T: crate::Serialize + crate::DeserializeOwned, const N: usize> Miniconf for [T; N] {
+impl<T: serde::Serialize + serde::de::DeserializeOwned, const N: usize> Miniconf for [T; N] {
     fn set_path<'a, 'b: 'a, P, D>(
         &mut self,
         path_parts: &mut P,

src/iter.rs

@@ -1,4 +1,4 @@
-use super::{IterError, Metadata, SerDe};
+use crate::{IterError, Metadata, SerDe};
 use core::{fmt::Write, marker::PhantomData};
 
 /// An iterator over the paths in a Miniconf namespace.

src/json.rs

@@ -0,0 +1,46 @@
+use crate::{Error, Miniconf, SerDe};
+use serde_json_core::{de, ser};
+
+/// Marker struct for the "JSON and `/`" [SerDe] specification.
+///
+/// Access items with `'/'` as path separator and JSON (from `serde-json-core`)
+/// as serialization/deserialization payload format.
+pub struct JsonCoreSlash;
+
+impl<T> SerDe<JsonCoreSlash> for T
+where
+    T: Miniconf,
+{
+    const SEPARATOR: char = '/';
+    type DeError = de::Error;
+    type SerError = ser::Error;
+
+    fn set(&mut self, path: &str, data: &[u8]) -> Result<usize, Error<Self::DeError>> {
+        let mut de = de::Deserializer::new(data);
+        self.set_path(&mut path.split(Self::SEPARATOR).skip(1), &mut de)?;
+        de.end().map_err(Error::PostDeserialization)
+    }
+
+    fn get(&self, path: &str, data: &mut [u8]) -> Result<usize, Error<Self::SerError>> {
+        let mut ser = ser::Serializer::new(data);
+        self.get_path(&mut path.split(Self::SEPARATOR).skip(1), &mut ser)?;
+        Ok(ser.end())
+    }
+}
+
+// These allow unifying serde error information to make writing examples
+// and tests easier. Doing this conversion is optional.
+// #[cfg(any(test, doctest))]
+impl From<Error<ser::Error>> for Error<de::Error> {
+    fn from(value: Error<ser::Error>) -> Self {
+        match value {
+            Error::BadIndex => Self::BadIndex,
+            Error::PathAbsent => Self::PathAbsent,
+            Error::PathNotFound => Self::PathNotFound,
+            Error::PathTooLong => Self::PathTooLong,
+            Error::PathTooShort => Self::PathTooShort,
+            Error::PostDeserialization(_) => Error::PostDeserialization(de::Error::CustomError),
+            Error::SerDe(_) => Self::SerDe(de::Error::CustomError),
+        }
+    }
+}