Rename wasm module, write readme.

Cargo.toml

@@ -6,7 +6,7 @@ members = [
     "bamboo-rs-core-test",
     "bamboo-rs-cli",
     "generate-test-vectors",
-    "bamboo-rs-wasm"
+    "bamboo-wasm"
 ]
 
 exclude = [

bamboo-rs-wasm/Cargo.toml → bamboo-wasm/Cargo.toml

@@ -1,6 +1,6 @@
 [package]
-name = "bamboo-rs-wasm"
-version = "0.5.0"
+name = "bamboo-wasm"
+version = "0.5.1"
 authors = ["Piet Geursen <[email protected]>"]
 edition = "2018"
 

bamboo-wasm/README.md

@@ -0,0 +1,98 @@
+# @bamboo-logs/bamboo-wasm
+
+`publish`, `verify` and `decode` bamboo entries from javascript / typescript.
+
+## About
+
+This is a low level module. It's unlikely you want this. See [@bamboo-logs/bamboo-log](https://www.npmjs.com/package/@bamboo-logs/bamboo-log) for a module that wraps these functions and provides an easier to use API.
+
+## Example
+
+Publish and verify our first entry!
+
+```js
+const {publish, verify, decode, KeyPair} = require('@bamboo-logs/bamboo-wasm')
+
+// Create a new cryptographic keypair for signing our entries
+const keyPair = new KeyPair()
+
+// The payload for our first entry
+const payload = Buffer.from("Hello World!")
+
+// The bamboo log id that we'll publish to. See the bamboo spec for more.
+// Note that logId is a BigInt because it can be up to 2^64 -1.
+const logId = 0n
+
+// Is this the entry the last entry for this logId?
+const isEndOfFeed = false
+
+// Publish our first entry!
+const entryBytes = publish(keyPair.publicKeyBytes(), keyPair.secretKeyBytes(), logId, payload, isEndOfFeed)
+
+// Decode the entry bytes as an `Entry` 
+const entry = decode(entryBytes)
+
+console.log(entry)
+
+try {
+  // verify throws (with a useful exception) if the entry is invalid
+  verify(entryBytes, payload)
+  console.log("Entry was valid")
+}catch(e){ }
+
+```
+
+Outputs:
+
+( Array contents omitted for clarity )
+
+```
+{
+  entryHash: Uint8Array(66) [ ... ],
+  payloadHash: Uint8Array(66) [ ... ],
+  lipmaaLinkHash: undefined,
+  backLinkHash: undefined,
+  signature: Uint8Array(64) [ ... ],
+  author: Uint8Array(32) [ ... ],
+  isEndOfFeed: false,
+  logId: 0n,
+  payloadSize: 12n,
+  sequence: 1n
+}
+Entry was valid
+```
+
+## Api
+
+See the Typescript types in `index.d.ts`
+
+### NPM
+
+[Published on npm](https://www.npmjs.com/package/@bamboo-logs/bamboo-wasm)
+
+### 🛠️ Build with `wasm-pack build`
+
+```
+wasm-pack build  -t nodejs --scope bamboo-logs --release --out-name index
+```
+
+### 🔬 Test in Headless Browsers with `wasm-pack test`
+
+```
+wasm-pack test --headless --firefox
+```
+
+### 🎁 Publish to NPM with `wasm-pack publish`
+
+```
+wasm-pack publish
+```
+
+## 🔋 Batteries Included
+
+* [`wasm-bindgen`](https://github.com/rustwasm/wasm-bindgen) for communicating
+  between WebAssembly and JavaScript.
+* [`console_error_panic_hook`](https://github.com/rustwasm/console_error_panic_hook)
+  for logging panic messages to the developer console.
+* [`wee_alloc`](https://github.com/rustwasm/wee_alloc), an allocator optimized
+  for small code size.

bamboo-rs-wasm/src/lib.rs → bamboo-wasm/src/lib.rs

@@ -138,7 +138,6 @@ pub fn verify(
 
 #[wasm_bindgen]
 pub fn publish(
-    out: &mut [u8],
     public_key: &[u8],
     secret_key: &[u8],
     log_id: u64,
@@ -147,7 +146,11 @@ pub fn publish(
     last_seq_num: Option<u64>,
     lipmaa_entry_vec: Option<Vec<u8>>,
     backlink_vec: Option<Vec<u8>>,
-) -> Result<usize, JsValue> {
+) -> Result<Vec<u8>, JsValue> {
+
+    let mut out = Vec::with_capacity(bamboo_rs_core::entry::MAX_ENTRY_SIZE);
+    out.resize(bamboo_rs_core::entry::MAX_ENTRY_SIZE, 0);
+
     let public_key =
         PublicKey::from_bytes(public_key).map_err(|e| JsValue::from_str(&e.to_string()))?;
 
@@ -160,7 +163,7 @@ pub fn publish(
     };
 
     publish_entry(
-        out,
+        &mut out[..],
         Some(&key_pair),
         log_id,
         payload,
@@ -170,6 +173,11 @@ pub fn publish(
         backlink_vec.as_ref().map(|vec| vec.as_slice()),
     )
     .map_err(|err| JsValue::from_str(&err.to_string()))
+    .map(|entry_size| {
+        out.truncate(entry_size);
+        out
+    })
+
 }
 
 //TODO: keygen.