serde_ipld_dagcbor crate NIF wrapper

lib/hexpds/dagcbor.ex

@@ -0,0 +1,7 @@
+defmodule Hexdps.DagCBOR do
+  defmodule Internal do
+    use Rustler, otp_app: :hexpds, crate: "hexpds_dagcbor_internal"
+      @spec encode_dag_cbor(binary()) :: {:ok, binary()} | {:error, String.t()}
+      def encode_dag_cbor(_json), do: :erlang.nif_error(:nif_not_loaded)
+  end
+end

native/hexpds_dagcbor_internal/.cargo/config.toml

@@ -0,0 +1,5 @@
+[target.'cfg(target_os = "macos")']
+rustflags = [
+    "-C", "link-arg=-undefined",
+    "-C", "link-arg=dynamic_lookup",
+]

native/hexpds_dagcbor_internal/.gitignore

@@ -0,0 +1,14 @@
+# Generated by Cargo
+# will have compiled files and executables
+debug/
+target/
+
+# Remove Cargo.lock from gitignore if creating an executable, leave it for libraries
+# More information here https://doc.rust-lang.org/cargo/guide/cargo-toml-vs-cargo-lock.html
+Cargo.lock
+
+# These are backup files generated by rustfmt
+**/*.rs.bk
+
+# MSVC Windows builds of rustc generate these, which store debugging information
+*.pdb

native/hexpds_dagcbor_internal/Cargo.toml

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+[package]
+name = "hexpds_dagcbor_internal"
+version = "0.1.0"
+authors = [ "NetWatchInc" ]
+edition = "2021"
+
+[lib]
+name = "hexpds_dagcbor_internal"
+path = "src/lib.rs"
+crate-type = ["cdylib"]
+
+[dependencies]
+rustler = "0.31.0"
+serde_ipld_dagcbor = "0.4.2"
+serde_json = "1.0.113"

native/hexpds_dagcbor_internal/README.md

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+# NIF for Elixir.Hexpds.DagCBOR.Internal
+
+## To build the NIF module:
+
+- Your NIF will now build along with your project.
+
+## To load the NIF:
+
+```elixir
+defmodule Hexpds.DagCBOR.Internal do
+  use Rustler, otp_app: :hexpds, crate: "hexpds_dagcbor_internal"
+
+  # When your NIF is loaded, it will override this function.
+  def encode_dag_cbor(json), do: :erlang.nif_error(:nif_not_loaded)
+end
+```
+
+## Examples
+
+[This](https://github.com/rusterlium/NifIo) is a complete example of a NIF written in Rust.

native/hexpds_dagcbor_internal/src/lib.rs

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+use rustler::Encoder;
+use rustler::Env;
+use rustler::Term;
+use serde_json::from_str;
+use serde_ipld_dagcbor::to_vec;
+
+mod atoms {
+    rustler::atoms! {
+        ok,
+        error,
+    }
+}
+
+#[rustler::nif]
+fn encode_dag_cbor(env: Env, json: String) -> Term {
+    let parsed_json = match from_str(&json) {
+        Ok(json) => json,
+        Err(e) => return (atoms::error(), format!("Failed to parse JSON: {}", e)).encode(env),
+    };
+
+    let cbor_data = match to_vec(&parsed_json) {
+        Ok(data) => data,
+        Err(e) => return (atoms::error(), format!("Failed to encode to DAG-CBOR: {}", e)).encode(env),
+    };
+
+    (atoms::ok(), cbor_data).encode(env)
+}
+
+rustler::init!("Elixir.Hexpds.DagCBOR.Internal", [encode_dag_cbor]);