Add client for hello contract (#196)

- Update video for hello

Author: yanganto

README.md

@@ -14,7 +14,7 @@ Furthermore, there is also [wiki site](https://github.com/second-state/SewUp/wik
 ## Slides & Demo
 | Date       | Event                 | Slides / Demo video                                                                                                                                                                            |
 |------------|-----------------------|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
-| 2021/09/07 | Version 0.1 release   | [KV](https://youtu.be/LUpYIFGG36s) [RDB](https://youtu.be/sJLOcJRheIw) [ERC-20](https://youtu.be/sVGEuNBY1dc) [ERC-721](https://youtu.be/ivZIqnhOAfA) [ERC-1155](https://youtu.be/BsbAFT5rNGw) |
+| 2021/09/07 | Version 0.1 release   | [Hello](https://youtu.be/kbe3uuxkBNQ), [KV](https://youtu.be/LUpYIFGG36s), [RDB](https://youtu.be/sJLOcJRheIw), [ERC-20](https://youtu.be/sVGEuNBY1dc), [ERC-721](https://youtu.be/ivZIqnhOAfA), [ERC-1155](https://youtu.be/BsbAFT5rNGw) |
 | 2021/06/22 | Rust online meetup    | [v0.0.2](https://slides.com/yanganto/ethereum-wasm-in-rust)                                                                                                                                    |
 | 2021/06/19 | Rust meetup (Beijing) | [v0.0.1-pre](https://slides.com/yanganto/sewup)                                                                                                                                                |
 

examples/hello-contract/Cargo.toml

@@ -7,13 +7,26 @@ description = "The example contract using sewup default feature"
 
 [lib]
 path = "src/lib.rs"
-crate-type = ["cdylib"]
+crate-type = ["cdylib", "lib"]
+
+[[bin]]
+name = "hello-client"
+path = "src/client.rs"
+required-features = ["client"]
 
 [dependencies]
 sewup ={ version = "*", path = "../../sewup" }
 sewup-derive = { version = "*", path = "../../sewup-derive" }
 anyhow = "1.0.40"
 
+cargo-sewup = { version = "*", path = "../../cargo-sewup", optional = true }
+web3 = { version = "0.16.0", optional = true }
+tokio = { version = "1.0", features = ["full"], optional = true }
+secp256k1 = { version = "0.20.3", optional = true }
+reqwest = { version = "0.11.4", features = ["json"], optional = true }
+serde_json = { version = "1.0.66", optional = true }
+bincode = { version = "1.3", optional = true }
+
 [profile.release]
 incremental = false
 panic = "abort"
@@ -32,3 +45,4 @@ address = "0xXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX"
 [features]
 constructor = []
 constructor-test = []
+client = [ "web3", "tokio", "secp256k1", "reqwest", "serde_json", "bincode", "cargo-sewup"]

examples/hello-contract/src/client.rs

@@ -0,0 +1,37 @@
+/// A example client to interact with kv-contract
+use std::str::FromStr;
+
+use anyhow::Result;
+use cargo_sewup::config::{get_deploy_config, Deploy};
+use sewup_derive::ewasm_input;
+use tokio;
+use web3::{
+    types::{Address, CallRequest},
+    Web3,
+};
+
+use hello_contract::*;
+
+#[tokio::main]
+async fn main() -> Result<()> {
+    // NOTE: modify the contract addr after you deploy the contract
+    let contract_addr = "0xc2f4023e7c181e4419da30eaaa01816afb23be08";
+
+    let Deploy { url, address, .. } = get_deploy_config().await?;
+
+    let transport = web3::transports::Http::new(&url)?;
+    let web3 = Web3::new(transport);
+
+    let input = ewasm_input!(None for hello);
+
+    let call_req = CallRequest {
+        from: Some(Address::from_str(&address)?),
+        data: Some(input.into()),
+        to: Some(Address::from_str(&contract_addr)?),
+        ..Default::default()
+    };
+
+    let resp = web3.eth().call(call_req, None).await?;
+    println!("resp from contract: {}", std::str::from_utf8(&resp.0)?);
+    Ok(())
+}

sewup-derive/src/lib.rs

@@ -518,17 +518,20 @@ pub fn ewasm_input(item: TokenStream) -> TokenStream {
     if let Some(cap) = re.captures(&item.to_string()) {
         let sig = cap.name("sig").unwrap().as_str();
         let instance = cap.name("instance").unwrap().as_str();
-        format!(
-            "{{
-            let mut input = {}.to_vec();
-            input.append(&mut bincode::serialize(&{}).unwrap());
-            input
-        }}",
-            write_function_signature(sig),
-            instance
-        )
-        .parse()
-        .unwrap()
+        let output = if instance == "None" {
+            format!("{}.to_vec()", write_function_signature(sig),)
+        } else {
+            format!(
+                "{{
+                let mut input = {}.to_vec();
+                input.append(&mut bincode::serialize(&{}).unwrap());
+                input
+            }}",
+                write_function_signature(sig),
+                instance
+            )
+        };
+        output.parse().unwrap()
     } else {
         panic!("ewasm_input input incorrect")
     }