Initial commit of handlebars helpers library

Cargo.toml

@@ -0,0 +1,8 @@
+[package]
+name = "handlebars-helpers"
+version = "0.1.0"
+authors = ["Adrian Malacoda <adrian.malacoda@monarch-pass.net>"]
+
+[dependencies]
+handlebars = "0.32.2"
+serde_json = "^1.0.0"

src/lib.rs

@@ -0,0 +1,25 @@
+extern crate handlebars;
+use serde_json::Value;
+use handlebars::{Handlebars, Helper, HelperDef, RenderContext, RenderError};
+
+extern crate serde_json;
+
+fn json_format_helper(helper: &Helper, _: &Handlebars, render_context: &mut RenderContext) -> Result<(), RenderError> {
+    let param = helper.param(0).ok_or(RenderError::new("Param 0 is required for format helper.",),)?;
+    render_context.writer.write(param.value().to_string().into_bytes().as_ref())?;
+    Ok(())
+}
+
+struct EqHelper;
+impl HelperDef for EqHelper {
+    fn call_inner(&self, helper: &Helper, _: &Handlebars, _: &mut RenderContext) -> Result<Option<Value>, RenderError> {
+        let param1 = helper.param(0).ok_or(RenderError::new("Param 0 is required for eq helper.",),)?.value();
+        let param2 = helper.param(1).ok_or(RenderError::new("Param 1 is required for eq helper.",),)?.value();
+        Ok(Some(Value::Bool(param1 == param2)))
+    }
+}
+
+pub fn register(handle: &mut Handlebars) {
+    handle.register_helper("JSONstringify", Box::new(json_format_helper));
+    handle.register_helper("eq", Box::new(EqHelper));
+}