1 files changed, 497 insertions, 0 deletions
diff --git a/extensions/fetch/lib.rs b/extensions/fetch/lib.rs
new file mode 100644
index 000000000..36a5b5afd
--- /dev/null
+++ b/extensions/fetch/lib.rs
@@ -0,0 +1,497 @@
+// Copyright 2018-2021 the Deno authors. All rights reserved. MIT license.
+
+use deno_core::error::bad_resource_id;
+use deno_core::error::generic_error;
+use deno_core::error::null_opbuf;
+use deno_core::error::type_error;
+use deno_core::error::AnyError;
+use deno_core::futures::Future;
+use deno_core::futures::Stream;
+use deno_core::futures::StreamExt;
+use deno_core::include_js_files;
+use deno_core::op_async;
+use deno_core::op_sync;
+use deno_core::url::Url;
+use deno_core::AsyncRefCell;
+use deno_core::CancelFuture;
+use deno_core::CancelHandle;
+use deno_core::CancelTryFuture;
+use deno_core::Extension;
+use deno_core::OpState;
+use deno_core::RcRef;
+use deno_core::Resource;
+use deno_core::ResourceId;
+use deno_core::ZeroCopyBuf;
+
+use data_url::DataUrl;
+use deno_file::BlobUrlStore;
+use reqwest::header::HeaderMap;
+use reqwest::header::HeaderName;
+use reqwest::header::HeaderValue;
+use reqwest::header::USER_AGENT;
+use reqwest::redirect::Policy;
+use reqwest::Body;
+use reqwest::Client;
+use reqwest::Method;
+use reqwest::Response;
+use serde::Deserialize;
+use serde::Serialize;
+use std::borrow::Cow;
+use std::cell::RefCell;
+use std::convert::From;
+use std::fs::File;
+use std::io::Read;
+use std::path::Path;
+use std::path::PathBuf;
+use std::pin::Pin;
+use std::rc::Rc;
+use tokio::io::AsyncReadExt;
+use tokio::sync::mpsc;
+use tokio_stream::wrappers::ReceiverStream;
+use tokio_util::io::StreamReader;
+
+pub use reqwest; // Re-export reqwest
+
+pub fn init<P: FetchPermissions + 'static>(
+  user_agent: String,
+  ca_data: Option<Vec<u8>>,
+) -> Extension {
+  Extension::builder()
+    .js(include_js_files!(
+      prefix "deno:extensions/fetch",
+      "01_fetch_util.js",
+      "11_streams.js",
+      "20_headers.js",
+      "21_formdata.js",
+      "22_body.js",
+      "22_http_client.js",
+      "23_request.js",
+      "23_response.js",
+      "26_fetch.js",
+    ))
+    .ops(vec![
+      ("op_fetch", op_sync(op_fetch::<P>)),
+      ("op_fetch_send", op_async(op_fetch_send)),
+      ("op_fetch_request_write", op_async(op_fetch_request_write)),
+      ("op_fetch_response_read", op_async(op_fetch_response_read)),
+      ("op_create_http_client", op_sync(op_create_http_client::<P>)),
+    ])
+    .state(move |state| {
+      state.put::<reqwest::Client>({
+        create_http_client(user_agent.clone(), ca_data.clone()).unwrap()
+      });
+      state.put::<HttpClientDefaults>(HttpClientDefaults {
+        ca_data: ca_data.clone(),
+        user_agent: user_agent.clone(),
+      });
+      Ok(())
+    })
+    .build()
+}
+
+pub struct HttpClientDefaults {
+  pub user_agent: String,
+  pub ca_data: Option<Vec<u8>>,
+}
+
+pub trait FetchPermissions {
+  fn check_net_url(&mut self, _url: &Url) -> Result<(), AnyError>;
+  fn check_read(&mut self, _p: &Path) -> Result<(), AnyError>;
+}
+
+/// For use with `op_fetch` when the user does not want permissions.
+pub struct NoFetchPermissions;
+
+impl FetchPermissions for NoFetchPermissions {
+  fn check_net_url(&mut self, _url: &Url) -> Result<(), AnyError> {
+    Ok(())
+  }
+
+  fn check_read(&mut self, _p: &Path) -> Result<(), AnyError> {
+    Ok(())
+  }
+}
+
+pub fn get_declaration() -> PathBuf {
+  PathBuf::from(env!("CARGO_MANIFEST_DIR")).join("lib.deno_fetch.d.ts")
+}
+
+#[derive(Deserialize)]
+#[serde(rename_all = "camelCase")]
+pub struct FetchArgs {
+  method: String,
+  url: String,
+  headers: Vec<(String, String)>,
+  client_rid: Option<u32>,
+  has_body: bool,
+}
+
+#[derive(Serialize)]
+#[serde(rename_all = "camelCase")]
+pub struct FetchReturn {
+  request_rid: ResourceId,
+  request_body_rid: Option<ResourceId>,
+}
+
+pub fn op_fetch<FP>(
+  state: &mut OpState,
+  args: FetchArgs,
+  data: Option<ZeroCopyBuf>,
+) -> Result<FetchReturn, AnyError>
+where
+  FP: FetchPermissions + 'static,
+{
+  let client = if let Some(rid) = args.client_rid {
+    let r = state
+      .resource_table
+      .get::<HttpClientResource>(rid)
+      .ok_or_else(bad_resource_id)?;
+    r.client.clone()
+  } else {
+    let client = state.borrow::<reqwest::Client>();
+    client.clone()
+  };
+
+  let method = Method::from_bytes(args.method.as_bytes())?;
+  let url = Url::parse(&args.url)?;
+
+  // Check scheme before asking for net permission
+  let scheme = url.scheme();
+  let (request_rid, request_body_rid) = match scheme {
+    "http" | "https" => {
+      let permissions = state.borrow_mut::<FP>();
+      permissions.check_net_url(&url)?;
+
+      let mut request = client.request(method, url);
+
+      let request_body_rid = if args.has_body {
+        match data {
+          None => {
+            // If no body is passed, we return a writer for streaming the body.
+            let (tx, rx) = mpsc::channel::<std::io::Result<Vec<u8>>>(1);
+            request = request.body(Body::wrap_stream(ReceiverStream::new(rx)));
+
+            let request_body_rid =
+              state.resource_table.add(FetchRequestBodyResource {
+                body: AsyncRefCell::new(tx),
+                cancel: CancelHandle::default(),
+              });
+
+            Some(request_body_rid)
+          }
+          Some(data) => {
+            // If a body is passed, we use it, and don't return a body for streaming.
+            request = request.body(Vec::from(&*data));
+            None
+          }
+        }
+      } else {
+        None
+      };
+
+      for (key, value) in args.headers {
+        let name = HeaderName::from_bytes(key.as_bytes()).unwrap();
+        let v = HeaderValue::from_str(&value).unwrap();
+        request = request.header(name, v);
+      }
+
+      let fut = request.send();
+
+      let request_rid = state
+        .resource_table
+        .add(FetchRequestResource(Box::pin(fut)));
+
+      (request_rid, request_body_rid)
+    }
+    "data" => {
+      let data_url = DataUrl::process(url.as_str())
+        .map_err(|e| type_error(format!("{:?}", e)))?;
+
+      let (body, _) = data_url
+        .decode_to_vec()
+        .map_err(|e| type_error(format!("{:?}", e)))?;
+
+      let response = http::Response::builder()
+        .status(http::StatusCode::OK)
+        .header(http::header::CONTENT_TYPE, data_url.mime_type().to_string())
+        .body(reqwest::Body::from(body))?;
+
+      let fut = async move { Ok(Response::from(response)) };
+
+      let request_rid = state
+        .resource_table
+        .add(FetchRequestResource(Box::pin(fut)));
+
+      (request_rid, None)
+    }
+    "blob" => {
+      let blob_url_storage =
+        state.try_borrow::<BlobUrlStore>().ok_or_else(|| {
+          type_error("Blob URLs are not supported in this context.")
+        })?;
+
+      let blob = blob_url_storage
+        .get(url)?
+        .ok_or_else(|| type_error("Blob for the given URL not found."))?;
+
+      if method != "GET" {
+        return Err(type_error("Blob URL fetch only supports GET method."));
+      }
+
+      let response = http::Response::builder()
+        .status(http::StatusCode::OK)
+        .header(http::header::CONTENT_LENGTH, blob.data.len())
+        .header(http::header::CONTENT_TYPE, blob.media_type)
+        .body(reqwest::Body::from(blob.data))?;
+
+      let fut = async move { Ok(Response::from(response)) };
+
+      let request_rid = state
+        .resource_table
+        .add(FetchRequestResource(Box::pin(fut)));
+
+      (request_rid, None)
+    }
+    _ => return Err(type_error(format!("scheme '{}' not supported", scheme))),
+  };
+
+  Ok(FetchReturn {
+    request_rid,
+    request_body_rid,
+  })
+}
+
+#[derive(Serialize)]
+#[serde(rename_all = "camelCase")]
+pub struct FetchResponse {
+  status: u16,
+  status_text: String,
+  headers: Vec<(String, String)>,
+  url: String,
+  response_rid: ResourceId,
+}
+
+pub async fn op_fetch_send(
+  state: Rc<RefCell<OpState>>,
+  rid: ResourceId,
+  _data: Option<ZeroCopyBuf>,
+) -> Result<FetchResponse, AnyError> {
+  let request = state
+    .borrow_mut()
+    .resource_table
+    .take::<FetchRequestResource>(rid)
+    .ok_or_else(bad_resource_id)?;
+
+  let request = Rc::try_unwrap(request)
+    .ok()
+    .expect("multiple op_fetch_send ongoing");
+
+  let res = match request.0.await {
+    Ok(res) => res,
+    Err(e) => return Err(type_error(e.to_string())),
+  };
+
+  //debug!("Fetch response {}", url);
+  let status = res.status();
+  let url = res.url().to_string();
+  let mut res_headers = Vec::new();
+  for (key, val) in res.headers().iter() {
+    let key_string = key.to_string();
+
+    if val.as_bytes().is_ascii() {
+      res_headers.push((key_string, val.to_str().unwrap().to_owned()))
+    } else {
+      res_headers.push((
+        key_string,
+        val
+          .as_bytes()
+          .iter()
+          .map(|&c| c as char)
+          .collect::<String>(),
+      ));
+    }
+  }
+
+  let stream: BytesStream = Box::pin(res.bytes_stream().map(|r| {
+    r.map_err(|err| std::io::Error::new(std::io::ErrorKind::Other, err))
+  }));
+  let stream_reader = StreamReader::new(stream);
+  let rid = state
+    .borrow_mut()
+    .resource_table
+    .add(FetchResponseBodyResource {
+      reader: AsyncRefCell::new(stream_reader),
+      cancel: CancelHandle::default(),
+    });
+
+  Ok(FetchResponse {
+    status: status.as_u16(),
+    status_text: status.canonical_reason().unwrap_or("").to_string(),
+    headers: res_headers,
+    url,
+    response_rid: rid,
+  })
+}
+
+pub async fn op_fetch_request_write(
+  state: Rc<RefCell<OpState>>,
+  rid: ResourceId,
+  data: Option<ZeroCopyBuf>,
+) -> Result<(), AnyError> {
+  let data = data.ok_or_else(null_opbuf)?;
+  let buf = Vec::from(&*data);
+
+  let resource = state
+    .borrow()
+    .resource_table
+    .get::<FetchRequestBodyResource>(rid)
+    .ok_or_else(bad_resource_id)?;
+  let body = RcRef::map(&resource, |r| &r.body).borrow_mut().await;
+  let cancel = RcRef::map(resource, |r| &r.cancel);
+  body.send(Ok(buf)).or_cancel(cancel).await??;
+
+  Ok(())
+}
+
+pub async fn op_fetch_response_read(
+  state: Rc<RefCell<OpState>>,
+  rid: ResourceId,
+  data: Option<ZeroCopyBuf>,
+) -> Result<usize, AnyError> {
+  let data = data.ok_or_else(null_opbuf)?;
+
+  let resource = state
+    .borrow()
+    .resource_table
+    .get::<FetchResponseBodyResource>(rid)
+    .ok_or_else(bad_resource_id)?;
+  let mut reader = RcRef::map(&resource, |r| &r.reader).borrow_mut().await;
+  let cancel = RcRef::map(resource, |r| &r.cancel);
+  let mut buf = data.clone();
+  let read = reader.read(&mut buf).try_or_cancel(cancel).await?;
+  Ok(read)
+}
+
+struct FetchRequestResource(
+  Pin<Box<dyn Future<Output = Result<Response, reqwest::Error>>>>,
+);
+
+impl Resource for FetchRequestResource {
+  fn name(&self) -> Cow<str> {
+    "fetchRequest".into()
+  }
+}
+
+struct FetchRequestBodyResource {
+  body: AsyncRefCell<mpsc::Sender<std::io::Result<Vec<u8>>>>,
+  cancel: CancelHandle,
+}
+
+impl Resource for FetchRequestBodyResource {
+  fn name(&self) -> Cow<str> {
+    "fetchRequestBody".into()
+  }
+}
+
+type BytesStream =
+  Pin<Box<dyn Stream<Item = Result<bytes::Bytes, std::io::Error>> + Unpin>>;
+
+struct FetchResponseBodyResource {
+  reader: AsyncRefCell<StreamReader<BytesStream, bytes::Bytes>>,
+  cancel: CancelHandle,
+}
+
+impl Resource for FetchResponseBodyResource {
+  fn name(&self) -> Cow<str> {
+    "fetchResponseBody".into()
+  }
+}
+
+struct HttpClientResource {
+  client: Client,
+}
+
+impl Resource for HttpClientResource {
+  fn name(&self) -> Cow<str> {
+    "httpClient".into()
+  }
+}
+
+impl HttpClientResource {
+  fn new(client: Client) -> Self {
+    Self { client }
+  }
+}
+
+#[derive(Deserialize, Default, Debug)]
+#[serde(rename_all = "camelCase")]
+#[serde(default)]
+pub struct CreateHttpClientOptions {
+  ca_file: Option<String>,
+  ca_data: Option<String>,
+}
+
+pub fn op_create_http_client<FP>(
+  state: &mut OpState,
+  args: CreateHttpClientOptions,
+  _zero_copy: Option<ZeroCopyBuf>,
+) -> Result<ResourceId, AnyError>
+where
+  FP: FetchPermissions + 'static,
+{
+  if let Some(ca_file) = args.ca_file.clone() {
+    let permissions = state.borrow_mut::<FP>();
+    permissions.check_read(&PathBuf::from(ca_file))?;
+  }
+
+  let defaults = state.borrow::<HttpClientDefaults>();
+
+  let cert_data =
+    get_cert_data(args.ca_file.as_deref(), args.ca_data.as_deref())?;
+  let client = create_http_client(
+    defaults.user_agent.clone(),
+    cert_data.or_else(|| defaults.ca_data.clone()),
+  )
+  .unwrap();
+
+  let rid = state.resource_table.add(HttpClientResource::new(client));
+  Ok(rid)
+}
+
+fn get_cert_data(
+  ca_file: Option<&str>,
+  ca_data: Option<&str>,
+) -> Result<Option<Vec<u8>>, AnyError> {
+  if let Some(ca_data) = ca_data {
+    Ok(Some(ca_data.as_bytes().to_vec()))
+  } else if let Some(ca_file) = ca_file {
+    let mut buf = Vec::new();
+    File::open(ca_file)?.read_to_end(&mut buf)?;
+    Ok(Some(buf))
+  } else {
+    Ok(None)
+  }
+}
+
+/// Create new instance of async reqwest::Client. This client supports
+/// proxies and doesn't follow redirects.
+pub fn create_http_client(
+  user_agent: String,
+  ca_data: Option<Vec<u8>>,
+) -> Result<Client, AnyError> {
+  let mut headers = HeaderMap::new();
+  headers.insert(USER_AGENT, user_agent.parse().unwrap());
+  let mut builder = Client::builder()
+    .redirect(Policy::none())
+    .default_headers(headers)
+    .use_rustls_tls();
+
+  if let Some(ca_data) = ca_data {
+    let cert = reqwest::Certificate::from_pem(&ca_data)?;
+    builder = builder.add_root_certificate(cert);
+  }
+
+  builder
+    .build()
+    .map_err(|e| generic_error(format!("Unable to build http client: {}", e)))
+}