feature: Upgrade the wasm demo developed by rust(#255) (#475)

demo/faas/code/rust/.gitignore

@@ -0,0 +1,15 @@
+# Generated by Cargo
+# will have compiled files and executables
+**/target/
+# These are backup files generated by rustfmt
+**/*.rs.bk
+
+.DS_Store
+
+# The cache for docker container dependency
+.cargo
+
+# The cache for chain data in container
+.local
+
+.idea/

demo/faas/code/rust/.rustfmt.toml

@@ -0,0 +1,7 @@
+format_strings = true
+group_imports = "StdExternalCrate"
+hex_literal_case = "Lower"
+imports_granularity = "Crate"
+reorder_impl_items = true
+use_field_init_shorthand = true
+wrap_comments = true

demo/faas/code/rust/Cargo.toml

@@ -0,0 +1,6 @@
+[profile.release]
+panic = "abort"
+lto = true
+
+[workspace]
+members = ["./client", "./proxy-wasm", "./server"]

demo/faas/code/rust/README.md

@@ -0,0 +1,5 @@
+# Build
+
+* `cargo build --target=wasm32-unknown-unknown --release`
+* Copy `target/wasm32-unknown-unknown/release/function_1.wasm` and `target/wasm32-unknown-unknown/release/function_2.wasm` to your actual directory.
+* Test the demo follow [https://mosn.io/layotto/#/zh/start/faas/start](https://mosn.io/layotto/#/zh/start/faas/start).

demo/faas/code/rust/client/Cargo.toml

@@ -0,0 +1,13 @@
+[package]
+name = "client"
+version = "0.1.0"
+edition = "2021"
+
+[lib]
+name = "function_1"
+crate-type = ["cdylib"]
+
+# See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
+
+[dependencies]
+proxy-wasm = { path = "../proxy-wasm" }

demo/faas/code/rust/client/src/lib.rs

@@ -0,0 +1,81 @@
+use std::str;
+
+use proxy_wasm::{
+    dispatcher, get_buffer, invoke_service, log, set_buffer,
+    traits::{Context, DefaultRootContext, HttpContext, RootContext},
+    types::*,
+};
+
+fn get_query_param(body: &str, param_name: &str) -> Option<String> {
+    for item in body.split("&") {
+        let key = format!("{:}=", param_name);
+        if item.starts_with(&key) {
+            return Some((&item[key.len()..]).to_owned());
+        }
+    }
+    None
+}
+
+fn get_book_name(body: &Option<Bytes>) -> Option<String> {
+    match body {
+        Some(body) => match str::from_utf8(body) {
+            Ok(body) => get_query_param(body, "name"),
+            _ => None,
+        },
+        None => None,
+    }
+}
+
+#[no_mangle]
+pub fn _start() {
+    dispatcher::set_root_context(|_| -> Box<dyn RootContext> {
+        Box::new(DefaultRootContext::<ClientHttpContext>::default())
+    });
+}
+
+#[no_mangle]
+#[allow(unused_must_use)]
+pub extern "C" fn proxy_get_id() {
+    set_buffer(BufferType::BufferTypeCallData, 0, b"id_1");
+}
+
+#[derive(Default)]
+struct ClientHttpContext {}
+
+impl Context for ClientHttpContext {}
+
+#[allow(unused_must_use)]
+impl HttpContext for ClientHttpContext {
+    fn on_http_request_body(&mut self, body_size: usize, _end_of_stream: bool) -> Action {
+        let book_name = get_buffer(BufferType::HttpRequestBody, 0, body_size)
+            .map_or(None, |buffer| get_book_name(&buffer));
+        match book_name {
+            Some(book_name) => match invoke_service("id_2", "", &book_name) {
+                Ok(response) => {
+                    let response = response.map_or("".to_string(), |v| {
+                        String::from_utf8(v).unwrap_or("".to_string())
+                    });
+                    set_buffer(
+                        BufferType::HttpResponseBody,
+                        0,
+                        format!("There are {:} inventories for {:}.\n", response, book_name)
+                            .as_bytes(),
+                    )
+                    .unwrap();
+                    Action::Continue
+                }
+                Err(status) => {
+                    log(
+                        LogLevel::Error,
+                        &format!("Invoke service failed: {}", status as u32),
+                    );
+                    Action::Pause
+                }
+            },
+            None => {
+                log(LogLevel::Error, "Param 'name' not found");
+                Action::Pause
+            }
+        }
+    }
+}

demo/faas/code/rust/proxy-wasm/Cargo.toml

@@ -0,0 +1,8 @@
+[package]
+name = "proxy-wasm"
+version = "0.1.0"
+edition = "2021"
+
+# See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
+
+[dependencies]