[cli] add generate-abi command (#209)

* [cli] add flag to `build` command to generate abi

* [cli] fix abi console output

* [cli] restore +nightly

* [cli] separate generate-abi command

* [cli] move nightly check to exec_cargo fn

* [cli] add test for generate_abi

cli/src/cmd/abi.rs

+// Copyright 2018-2019 Parity Technologies (UK) Ltd.
+// This file is part of ink!.
+//
+// ink! is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// ink! is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with ink!.  If not, see <http://www.gnu.org/licenses/>.
+
+use crate::cmd::{
+    Result,
+};
+use cargo_metadata::MetadataCommand;
+use std::path::PathBuf;
+
+/// Executes build of the smart-contract which produces a wasm binary that is ready for deploying.
+///
+/// It does so by invoking build by cargo and then post processing the final binary.
+pub(crate) fn execute_generate_abi(dir: Option<&PathBuf>) -> Result<String> {
+    println!(" Generating abi");
+
+    super::exec_cargo("run", &[
+        "--package",
+        "abi-gen",
+        "--verbose",
+    ], dir)?;
+
+    let metadata = MetadataCommand::new().exec()?;
+    let mut abi_path = metadata.target_directory.clone();
+    abi_path.push("abi.json");
+
+    Ok(format!(
+        "Your abi file is ready.\nYou can find it here:\n{}",
+        abi_path.display()
+    ))
+}
+
+#[cfg(test)]
+mod tests {
+    use crate::{
+        cmd::{
+            execute_new,
+            execute_generate_abi,
+            tests::with_tmp_dir,
+        },
+        AbstractionLayer,
+    };
+
+    #[test]
+    fn generate_abi() {
+        with_tmp_dir(|path| {
+            execute_new(AbstractionLayer::Lang, "new_project", Some(path))
+                .expect("new project creation failed");
+            let working_dir = path.join("new_project");
+            super::execute_generate_abi(Some(&working_dir)).expect("generate abi failed");
+
+            let mut abi_file = working_dir.clone();
+            abi_file.push("target");
+            abi_file.push("abi.json");
+            assert!(abi_file.exists())
+        });
+    }
+}

cli/src/cmd/build.rs

@@ -25,14 +25,7 @@ use parity_wasm::elements::{
     Module,
     Section,
 };
-use std::{
-    io::{
-        self,
-        Write,
-    },
-    path::PathBuf,
-    process::Command,
-};
+use std::path::PathBuf;
 
 /// This is the maximum number of pages available for a contract to allocate.
 const MAX_MEMORY_PAGES: u32 = 16;
@@ -96,43 +89,12 @@ pub fn collect_crate_metadata(working_dir: Option<&PathBuf>) -> Result<CrateMeta
 ///
 /// Currently it assumes that user wants to use `+nightly`.
 fn build_cargo_project(working_dir: Option<&PathBuf>) -> Result<()> {
-    let mut cmd = Command::new("cargo");
-    let mut is_nightly_cmd = Command::new("cargo");
-    if let Some(dir) = working_dir {
-        cmd.current_dir(dir);
-        is_nightly_cmd.current_dir(dir);
-    }
-
-    let is_nightly_default = is_nightly_cmd
-        .arg("--version")
-        .output()
-        .map_err(|_| ())
-        .and_then(|o| String::from_utf8(o.stdout).map_err(|_| ()))
-        .unwrap_or_default()
-        .contains("-nightly");
-
-    if !is_nightly_default {
-        cmd.arg("+nightly");
-    }
-
-    let output = cmd
-        .args(&[
-            "build",
-            "--no-default-features",
-            "--release",
-            "--target=wasm32-unknown-unknown",
-            "--verbose",
-        ])
-        .output()?;
-
-    if !output.status.success() {
-        // Dump the output streams produced by cargo into the stdout/stderr.
-        io::stdout().write_all(&output.stdout)?;
-        io::stderr().write_all(&output.stderr)?;
-        return Err(Error::BuildFailed)
-    }
-
-    Ok(())
+    super::exec_cargo("build", &[
+        "--no-default-features",
+        "--release",
+        "--target=wasm32-unknown-unknown",
+        "--verbose",
+    ], working_dir)
 }
 
 /// Ensures the wasm memory import of a given module has the maximum number of pages.

cli/src/cmd/mod.rs

@@ -14,12 +14,23 @@
 // You should have received a copy of the GNU General Public License
 // along with ink!.  If not, see <http://www.gnu.org/licenses/>.
 
+use std::{
+    io::{
+        self,
+        Write,
+    },
+    path::PathBuf,
+    process::Command,
+};
+
+mod abi;
 mod build;
 mod deploy;
 mod error;
 mod new;
 
 pub(crate) use self::{
+    abi::execute_generate_abi,
     build::execute_build,
     deploy::execute_deploy,
     error::{
@@ -29,6 +40,41 @@ pub(crate) use self::{
     new::execute_new,
 };
 
+fn exec_cargo(command: &str, args: &[&'static str], working_dir: Option<&PathBuf>) -> Result<()> {
+    let mut cmd = Command::new("cargo");
+    let mut is_nightly_cmd = Command::new("cargo");
+    if let Some(dir) = working_dir {
+        cmd.current_dir(dir);
+        is_nightly_cmd.current_dir(dir);
+    }
+
+    let is_nightly_default = is_nightly_cmd
+        .arg("--version")
+        .output()
+        .map_err(|_| ())
+        .and_then(|o| String::from_utf8(o.stdout).map_err(|_| ()))
+        .unwrap_or_default()
+        .contains("-nightly");
+
+    if !is_nightly_default {
+        cmd.arg("+nightly");
+    }
+
+    let output = cmd
+        .arg(command)
+        .args(args)
+        .output()?;
+
+    if !output.status.success() {
+        // Dump the output streams produced by cargo into the stdout/stderr.
+        io::stdout().write_all(&output.stdout)?;
+        io::stderr().write_all(&output.stderr)?;
+        return Err(error::CommandError::BuildFailed)
+    }
+
+    Ok(())
+}
+
 #[cfg(test)]
 mod tests {
     use std::path::PathBuf;

cli/src/main.rs

@@ -94,6 +94,9 @@ enum Command {
     /// Builds the smart contract.
     #[structopt(name = "build")]
     Build {},
+    /// Generate abi artifacts
+    #[structopt(name = "generate-abi")]
+    GenerateAbi {},
     /// Test the smart contract off-chain.
     #[structopt(name = "test")]
     Test {},
@@ -142,6 +145,7 @@ fn exec(cmd: Command) -> cmd::Result<String> {
             target_dir,
         } => cmd::execute_new(*layer, name, target_dir.as_ref()),
         Command::Build {} => cmd::execute_build(None),
+        Command::GenerateAbi {} => cmd::execute_generate_abi(None),
         Command::Test {} => Err(CommandError::UnimplementedCommand),
         Command::Deploy {
             url,