Dockerless build option

build.sh

@@ -0,0 +1,62 @@
+#!/bin/bash
+# build and pack a rust lambda library
+# https://aws.amazon.com/blogs/opensource/rust-runtime-for-aws-lambda/
+
+set -eo pipefail
+mkdir -p target/lambda
+export PROFILE=${PROFILE:-release}
+export DEBUGINFO=${DEBUGINFO}
+# cargo uses different names for target
+# of its build profiles
+if [[ "${PROFILE}" == "release" ]]; then
+    TARGET_PROFILE="${PROFILE}"
+else
+    TARGET_PROFILE="debug"
+fi
+export CARGO_TARGET_DIR=$PWD/target/lambda
+(
+    if [[ $# -gt 0 ]]; then
+        yum install -y "$@"
+    fi
+    # source cargo
+    . $HOME/.cargo/env
+    # cargo only supports --release flag for release
+    # profiles. dev is implicit
+    if [ "${PROFILE}" == "release" ]; then
+        cargo build ${CARGO_FLAGS:-} --${PROFILE}
+    else
+        cargo build ${CARGO_FLAGS:-}
+    fi
+) 1>&2
+
+function package() {
+    file="$1"
+    if [[ "${PROFILE}" == "release" ]] && [[ -z "${DEBUGINFO}" ]]; then
+        objcopy --only-keep-debug "$file" "$file.debug"
+        objcopy --strip-debug --strip-unneeded "$file"
+        objcopy --add-gnu-debuglink="$file.debug" "$file"
+    fi
+    rm "$file.zip" > 2&>/dev/null || true
+    # note: would use printf "@ $(basename $file)\n@=bootstrap" | zipnote -w "$file.zip"
+    # if not for https://bugs.launchpad.net/ubuntu/+source/zip/+bug/519611
+    if [ "$file" != ./bootstrap ] && [ "$file" != bootstrap ]; then
+        mv "${file}" bootstrap
+        mv "${file}.debug" bootstrap.debug > 2&>/dev/null || true
+    fi
+    zip "$file.zip" bootstrap
+    rm bootstrap
+}
+
+cd "${CARGO_TARGET_DIR}/${TARGET_PROFILE}"
+(
+    . $HOME/.cargo/env
+    if [ -z "$BIN" ]; then
+        IFS=$'\n'
+        for executable in $(cargo metadata --no-deps --format-version=1 | jq -r '.packages[] | .targets[] | select(.kind[] | contains("bin")) | .name'); do
+          package "$executable"
+        done
+    else
+        package "$BIN"
+    fi
+
+) 1>&2

index.js

@@ -4,7 +4,7 @@
 // https://serverless.com/framework/docs/providers/aws/guide/plugins/
 // https://github.com/softprops/lambda-rust/
 
-const { spawnSync } = require("child_process");
+const { spawnSync, execSync } = require("child_process");
 const { homedir } = require("os");
 const path = require("path");
 
@@ -50,11 +50,49 @@ class RustPlugin {
     this.serverless.service.package.excludeDevDependencies = false;
   }
 
-  runDocker(funcArgs, cargoPackage, binary, profile) {
+  compileFunctionBinary({
+    funcArgs,
+    cargoPackage,
+    binary,
+    profile,
+    dockerless
+  }) {
+    if (dockerless) {
+      return this.buildFromShell({ funcArgs, cargoPackage, binary, profile });
+    }
+    return this.buildInDocker({ funcArgs, cargoPackage, binary, profile });
+  }
+
+  buildInDocker({ funcArgs, cargoPackage, binary, profile }) {
+    const dockerTag = (funcArgs || {}).dockerTag || this.custom.dockerTag;
+    return spawnSync(
+      "docker",
+      [
+        ...this.getDockerArgs({ funcArgs, cargoPackage, binary, profile }),
+        `softprops/lambda-rust:${dockerTag}`
+      ],
+      NO_OUTPUT_CAPTURE
+    );
+  }
+
+  buildFromShell({ funcArgs, cargoPackage, binary, profile }) {
+    const buildCommand = [`BIN=${binary}`, `${__dirname}/build.sh`];
+    const cargoFlags = this.getCargoFlags(funcArgs, cargoPackage);
+    if (cargoFlags) {
+      buildCommand.unshift(`CARGO_FLAGS="${cargoFlags}"`);
+    }
+    if (profile) {
+      buildCommand.unshift(`PROFILE=${profile}`);
+    }
+
+    return execSync(`${buildCommand.join(" ")}`);
+  }
+
+  getDockerArgs({ funcArgs, cargoPackage, binary, profile }) {
     const cargoHome = process.env.CARGO_HOME || path.join(homedir(), ".cargo");
     const cargoRegistry = path.join(cargoHome, "registry");
     const cargoDownloads = path.join(cargoHome, "git");
-    const defaultArgs = [
+    const args = [
       "run",
       "--rm",
       "-t",
@@ -67,30 +105,29 @@ class RustPlugin {
       `-v`,
       `${cargoDownloads}:/root/.cargo/git`
     ];
-    const customArgs = [];
-
-    let cargoFlags = (funcArgs || {}).cargoFlags || this.custom.cargoFlags;
+    const cargoFlags = this.getCargoFlags(funcArgs, cargoPackage);
+    if (cargoFlags) {
+      // --features awesome-feature, ect
+      args.push("-e", `CARGO_FLAGS=${cargoFlags}`);
+    }
     if (profile) {
       // release or dev
-      customArgs.push("-e", `PROFILE=${profile}`);
+      args.push("-e", `PROFILE=${profile}`);
     }
+    return args;
+  }
+
+  getCargoFlags(funcArgs, cargoPackage) {
+    let cargoFlags = (funcArgs || {}).cargoFlags || this.custom.cargoFlags;
     if (cargoPackage != undefined) {
       if (cargoFlags) {
         cargoFlags = `${cargoFlags} -p ${cargoPackage}`;
       } else {
         cargoFlags = ` -p ${cargoPackage}`;
       }
     }
-    if (cargoFlags) {
-      // --features awesome-feature, ect
-      customArgs.push("-e", `CARGO_FLAGS=${cargoFlags}`);
-    }
-    const dockerTag = (funcArgs || {}).dockerTag || this.custom.dockerTag;
-    return spawnSync(
-      "docker",
-      [...defaultArgs, ...customArgs, `softprops/lambda-rust:${dockerTag}`],
-      NO_OUTPUT_CAPTURE
-    );
+
+    return cargoFlags;
   }
 
   functions() {
@@ -121,10 +158,16 @@ class RustPlugin {
       }
       this.serverless.cli.log(`Building native Rust ${func.handler} func...`);
       let profile = (func.rust || {}).profile || this.custom.profile;
-      const res = this.runDocker(func.rust, cargoPackage, binary, profile);
+      const res = this.compileFunctionBinary({
+        rust: func.rust,
+        cargoPackage,
+        binary,
+        profile,
+        dockerless: this.custom.dockerless
+      });
       if (res.error || res.status > 0) {
         this.serverless.cli.log(
-          `Dockerized Rust build encountered an error: ${res.error} ${res.status}.`
+          `Rust build encountered an error: ${res.error} ${res.status}.`
         );
         throw new Error(res.error);
       }

package.json

@@ -35,6 +35,7 @@
   "files": [
     "index.js",
     "package.json",
+    "build.sh",
     "README.md"
   ]
 }

tests/test.sh

@@ -10,7 +10,7 @@ export SILENT=1
 
 source "${HERE}"/bashtest.sh
 
-for project in  test-func test-func-dev; do
+for project in  test-func test-func-dev test-func-dockerless; do
 
     cd "${HERE}"/"${project}"
     echo "👩‍🔬 Running tests for $project"