fix: fix several issues with JS bindings

.github/workflows/wasmstan.yml

@@ -20,7 +20,7 @@ jobs:
         targets: wasm32-unknown-unknown,wasm32-wasip1
     - uses: taiki-e/install-action@v2
       with:
-        tool: cargo-binstall,just,wasmtime
+        tool: cargo-binstall,just,ripgrep,wasmtime
     - name: Install deps
       run: just components/install-deps
     - uses: actions/setup-node@v4

components/js/prophet-wasmstan/README.md

@@ -26,3 +26,24 @@ prophet.predict({ ds: [ 1713717414 ]})
 ```
 
 See the documentation for `@bsull/augurs` for more details.
+
+## Troubleshooting
+
+### Webpack
+
+The generated Javascript bindings in this package may require some additional Webpack configuration to work.
+Adding this to your `webpack.config.js` should be enough:
+
+```javascript
+{
+  experiments: {
+    // Required to load WASM modules.
+    asyncWebAssembly: true,
+  },
+  resolve: {
+    fallback: {
+      fs: false,
+    },
+  },
+}
+```

components/js/prophet-wasmstan/run.js

@@ -0,0 +1,17 @@
+// Note: this function comes from https://stackoverflow.com/questions/30401486/ecma6-generators-yield-promise.
+// It is used to convert a generator function into a promise.
+// `jco transpile` generates a similar function but it didn't work for me.
+// I'm not sure why, but I'll raise an issue on the `jco` repo.
+// See the `justfile` for how this gets shimmed into the transpiled code;
+// in short, we use `ripgrep` as in
+// https://unix.stackexchange.com/questions/181180/replace-multiline-string-in-files
+// (it was a Stack-Overflow heavy day...)
+// The indentation is intentional so the function matches the original.
+  function run(g) {
+    return Promise.resolve(function step(v) {
+      const res = g.next(v);
+      if (res.done) return res.value;
+      return res.value.then(step);
+    }());
+  }
+  return run(gen);

components/justfile

@@ -74,21 +74,17 @@ transpile: build
     --name prophet-wasmstan \
     --out-dir js/prophet-wasmstan \
     cpp/prophet-wasmstan/wit/prophet-wasmstan.wit
-
-transpile-min: build
-  jco transpile \
-    --name prophet-wasmstan \
-    --minify \
-    --optimize \
-    --out-dir js/prophet-wasmstan \
-    cpp/prophet-wasmstan/prophet-wasmstan-component.wasm
-  jco types \
-    --name prophet-wasmstan \
-    --out-dir js/prophet-wasmstan \
-    cpp/prophet-wasmstan/wit/prophet-wasmstan.wit
+  rg --replace="$(rg --invert-match --no-line-number '//' js/prophet-wasmstan/run.js)" \
+    --multiline --multiline-dotall \
+    --passthru \
+    --no-line-number \
+    '  let promise, resolve, reject;.+?return promise \|\| maybeSyncReturn;' \
+    js/prophet-wasmstan/prophet-wasmstan.js \
+    > js/prophet-wasmstan/prophet-wasmstan.fixed.js
+  mv js/prophet-wasmstan/prophet-wasmstan.fixed.js js/prophet-wasmstan/prophet-wasmstan.js
 
 test: transpile
   cd js/prophet-wasmstan && npm ci && npm run test:ci
 
-publish: transpile-min
+publish: transpile
   cd js/prophet-wasmstan && npm ci && npm publish --access public

crates/augurs-js/README.md

@@ -8,7 +8,7 @@ Javascript bindings to the [`augurs`][repo] time series framework.
 
 ```json
 "dependencies": {
-    "@bsull/augurs": "^0.3.0"
+    "@bsull/augurs": "^0.4.1"
 }
 ```
 
@@ -36,4 +36,30 @@ const { point, lower, upper } = model.predictInSample(predictionInterval);
 const { point: futurePoint, lower: futureLower, upper: futureUpper } = model.predict(10, predictionInterval);
 ```
 
+## Troubleshooting
+
+### Webpack
+
+Some of the dependencies of `augurs` require a few changes to the Webpack configuration to work correctly.
+Adding this to your `webpack.config.js` should be enough:
+
+```javascript
+{
+  experiments: {
+    // Required to load WASM modules.
+    asyncWebAssembly: true,
+  },
+  module: {
+    rules: [
+      {
+        test: /\@bsull\/augurs\/.*\.js$/,
+        resolve: {
+          fullySpecified: false
+        }
+      },
+    ]
+  },
+}
+```
+
 [repo]: https://github.com/grafana/augurs

crates/augurs-js/src/prophet.rs

@@ -1,4 +1,4 @@
-use std::{collections::HashMap, mem, num::TryFromIntError};
+use std::{collections::HashMap, num::TryFromIntError};
 
 use augurs_prophet::PositiveFloat;
 use js_sys::{Float64Array, Int32Array};
@@ -414,28 +414,14 @@ struct Logs {
     pub error: String,
     /// Fatal logs.
     pub fatal: String,
-
-    #[serde(default, skip)]
-    emitted_header: bool,
 }
 
 impl Logs {
-    fn emit(mut self) {
-        let debug = mem::take(&mut self.debug);
-        let info = mem::take(&mut self.info);
-        let warn = mem::take(&mut self.warn);
-        let error = mem::take(&mut self.error);
-        let fatal = mem::take(&mut self.fatal);
-        for line in debug.lines() {
+    fn emit(self) {
+        for line in self.debug.lines() {
             tracing::trace!(target: "augurs::prophet::stan::optimize", "{}", line);
         }
-        for line in info.lines() {
-            if line.contains("Iter") {
-                if self.emitted_header {
-                    return;
-                }
-                self.emitted_header = true;
-            }
+        for line in self.info.lines().filter(|line| !line.contains("Iter")) {
             match ConvergenceLog::new(line) {
                 Some(log) => {
                     tracing::debug!(
@@ -455,13 +441,13 @@ impl Logs {
                 }
             }
         }
-        for line in warn.lines() {
+        for line in self.warn.lines() {
             tracing::warn!(target: "augurs::prophet::stan::optimize", "{}", line);
         }
-        for line in error.lines() {
+        for line in self.error.lines() {
             tracing::error!(target: "augurs::prophet::stan::optimize", "{}", line);
         }
-        for line in fatal.lines() {
+        for line in self.fatal.lines() {
             tracing::error!(target: "augurs::prophet::stan::optimize", "{}", line);
         }
     }
@@ -488,6 +474,7 @@ struct OptimizedParams {
     /// Trend offset.
     pub m: f64,
     /// Observation noise.
+    #[tsify(type = "number")]
     pub sigma_obs: PositiveFloat,
     /// Trend rate adjustments.
     #[tsify(type = "Float64Array")]

crates/augurs-prophet/src/positive_float.rs

@@ -2,7 +2,7 @@
 #[repr(transparent)]
 #[derive(Debug, Clone, Copy, PartialEq, PartialOrd)]
 #[cfg_attr(feature = "bytemuck", derive(bytemuck::Pod, bytemuck::Zeroable))]
-#[cfg_attr(feature = "serde", derive(serde::Serialize, serde::Deserialize))]
+#[cfg_attr(feature = "serde", derive(serde::Serialize))]
 pub struct PositiveFloat(f64);
 
 /// An invalid float was provided when trying to create a [`PositiveFloat`].
@@ -48,3 +48,14 @@ impl From<PositiveFloat> for f64 {
         value.0
     }
 }
+
+#[cfg(feature = "serde")]
+impl<'de> serde::Deserialize<'de> for PositiveFloat {
+    fn deserialize<D>(deserializer: D) -> Result<Self, D::Error>
+    where
+        D: serde::Deserializer<'de>,
+    {
+        let f = f64::deserialize(deserializer)?;
+        Self::try_new(f).map_err(serde::de::Error::custom)
+    }
+}