3 files changed, 23 insertions, 6 deletions
diff --git a/dhall/Cargo.toml b/dhall/Cargo.toml
index 376506f..adf92d6 100644
--- a/dhall/Cargo.toml
+++ b/dhall/Cargo.toml
@@ -19,13 +19,20 @@ once_cell = "1.3.1"
 percent-encoding = "2.1.0"
 pest = "2.1"
 pest_consume = "1.0"
-reqwest = { version = "0.10", features = ["blocking"] }
 serde = "1.0"
 serde_cbor = "0.9.0"
 sha2 = "0.8.1"
 smallvec = "1.0.0"
 url = "2.1"
 
+[target.'cfg(not(target_arch = "wasm32"))'.dependencies]
+reqwest = { version = "0.10", features = ["blocking"] }
+
+[target.'cfg(target_arch = "wasm32")'.dependencies]
+# Disable native tls because hyper doesn't build on wasm
+reqwest = { version = "0.10", default-features = false }
+blocking = "0.4.3"
+
 [dev-dependencies]
 pretty_assertions = "0.6.1"
 version-sync = "0.8"
diff --git a/dhall/src/semantics/parse.rs b/dhall/src/semantics/parse.rs
index 2326471..82396e0 100644
--- a/dhall/src/semantics/parse.rs
+++ b/dhall/src/semantics/parse.rs
@@ -4,7 +4,7 @@ use std::path::Path;
 use url::Url;
 
 use crate::error::Error;
-use crate::semantics::resolve::ImportLocation;
+use crate::semantics::resolve::{download_http_text, ImportLocation};
 use crate::syntax::binary;
 use crate::syntax::parse_expr;
 use crate::Parsed;
@@ -17,7 +17,7 @@ pub fn parse_file(f: &Path) -> Result<Parsed, Error> {
 }
 
 pub fn parse_remote(url: Url) -> Result<Parsed, Error> {
-    let body = reqwest::blocking::get(url.clone()).unwrap().text().unwrap();
+    let body = download_http_text(url.clone())?;
     let expr = parse_expr(&body)?;
     let root = ImportLocation::Remote(url);
     Ok(Parsed(expr, root))
diff --git a/dhall/src/semantics/resolve/resolve.rs b/dhall/src/semantics/resolve/resolve.rs
index 3b72b9e..fb770db 100644
--- a/dhall/src/semantics/resolve/resolve.rs
+++ b/dhall/src/semantics/resolve/resolve.rs
@@ -159,9 +159,7 @@ impl ImportLocation {
     fn fetch_text(self) -> Result<String, Error> {
         Ok(match self {
             ImportLocation::Local(path) => std::fs::read_to_string(&path)?,
-            ImportLocation::Remote(url) => {
-                reqwest::blocking::get(url).unwrap().text().unwrap()
-            }
+            ImportLocation::Remote(url) => download_http_text(url)?,
             ImportLocation::Env(var_name) => match env::var(var_name) {
                 Ok(val) => val,
                 Err(_) => return Err(ImportError::MissingEnvVar.into()),
@@ -197,6 +195,18 @@ fn mkexpr(kind: UnspannedExpr) -> Expr {
     Expr::new(kind, Span::Artificial)
 }
 
+// TODO: error handling
+#[cfg(not(target_arch = "wasm32"))]
+pub(crate) fn download_http_text(url: Url) -> Result<String, Error> {
+    Ok(reqwest::blocking::get(url).unwrap().text().unwrap())
+}
+#[cfg(target_arch = "wasm32")]
+pub(crate) fn download_http_text(url: Url) -> Result<String, Error> {
+    blocking::block_on(async {
+        Ok(reqwest::get(url).await.unwrap().text().await.unwrap())
+    })
+}
+
 fn make_aslocation_uniontype() -> Expr {
     let text_type = mkexpr(ExprKind::Builtin(Builtin::Text));
     let mut union = BTreeMap::default();