Use sk-cbor library instead of serde_cbor

 - Bump crate version to 0.2.0
 - Move to be no_std; drop use of maplit crate in tests.
 - Change encoding methods to consume `self`.
 - Change encoding methods to be fallible.

Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "coset"
-version = "0.1.2"
+version = "0.2.0"
 authors = ["David Drysdale <[email protected]>"]
 edition = "2018"
 license = "Apache-2.0"
@@ -10,9 +10,7 @@ keywords = ["cryptography", "cose"]
 categories = ["cryptography"]
 
 [dependencies]
-maplit = "^1.0"
-serde_cbor = { version = "^0.11.1", features = ["std", "tags"] }
-serde = { version = "^1.0.127", features = ["derive"] }
+sk-cbor = "^0.1.0"
 
 [dev-dependencies]
 hex = "^0.4.2"

README.md

@@ -6,13 +6,17 @@
 
 This crate holds a set of Rust types for working with CBOR Object Signing and Encryption (COSE) objects, as defined in
 [RFC 8152](https://tools.ietf.org/html/rfc8152).  It builds on the core [CBOR](https://tools.ietf.org/html/rfc7049)
-parsing functionality from the [`serde_cbor` crate](https://docs.rs/serde_cbor).
+parsing functionality from the [`sk-cbor` crate](https://docs.rs/sk-cbor).
 
 See [crate docs](https://google.github.io/coset/rust/coset/index.html), or the [signature
 example](examples/signature.rs) for documentation on how to use the code.
 
 **This repo is under construction** and so details of the API and the code may change without warning.
 
+## `no_std` Support
+
+This crate supports `no_std`, but uses the `alloc` crate.
+
 ## Working on the Code
 
 Local coding conventions are enforced by the [continuous integration jobs](.github/workflows) and include:

examples/signature.rs

@@ -15,7 +15,6 @@
 ////////////////////////////////////////////////////////////////////////////////
 
 //! Example program demonstrating signature creation.
-
 use coset::{iana, CborSerializable};
 
 #[derive(Copy, Clone)]
@@ -62,7 +61,7 @@ fn main() {
         "'{}' + '{}' => {}",
         String::from_utf8_lossy(pt),
         String::from_utf8_lossy(aad),
-        hex::encode(sign1.to_vec().unwrap())
+        hex::encode(&sign1_data)
     );
 
     // At the receiving end, deserialize the bytes back to a `CoseSign1` object.