lambda-zig/build.zig
2021-10-03 13:07:47 -07:00

175 lines
8.7 KiB
Zig

const builtin = @import("builtin");
const std = @import("std");
const pkgs = @import("deps.zig").pkgs;
pub fn build(b: *std.build.Builder) !void {
// Standard target options allows the person running `zig build` to choose
// what target to build for. Here we do not override the defaults, which
// means any target is allowed, and the default is native. Other options
// for restricting supported target set are available.
// We want the target to be aarch64-linux for deploys
const target = std.zig.CrossTarget{
.cpu_arch = .aarch64,
.os_tag = .linux,
};
// Standard release options allow the person running `zig build` to select
// between Debug, ReleaseSafe, ReleaseFast, and ReleaseSmall.
// const mode = b.standardReleaseOptions();
const exe = b.addExecutable("bootstrap", "src/main.zig");
pkgs.addAllTo(exe);
exe.setTarget(target);
exe.setBuildMode(.ReleaseSafe);
const debug = b.option(bool, "debug", "Debug mode (do not strip executable)") orelse false;
exe.strip = !debug;
exe.install();
// TODO: We can cross-compile of course, but stripping and zip commands
// may vary
if (std.builtin.os.tag == .linux) {
// Package step
const package_step = b.step("package", "Package the function");
package_step.dependOn(b.getInstallStep());
// strip may not be installed or work for the target arch
// TODO: make this much less fragile
const strip = if (debug)
try std.fmt.allocPrint(b.allocator, "true", .{})
else
try std.fmt.allocPrint(b.allocator, "[ -x /usr/aarch64-linux-gnu/bin/strip ] && /usr/aarch64-linux-gnu/bin/strip {s}", .{b.getInstallPath(exe.install_step.?.dest_dir, exe.install_step.?.artifact.out_filename)});
defer b.allocator.free(strip);
package_step.dependOn(&b.addSystemCommand(&.{ "/bin/sh", "-c", strip }).step);
const function_zip = b.getInstallPath(exe.install_step.?.dest_dir, "function.zip");
const zip = try std.fmt.allocPrint(b.allocator, "zip -qj9 {s} {s}", .{ function_zip, b.getInstallPath(exe.install_step.?.dest_dir, exe.install_step.?.artifact.out_filename) });
defer b.allocator.free(zip);
package_step.dependOn(&b.addSystemCommand(&.{ "/bin/sh", "-c", zip }).step);
// Deployment
const deploy_step = b.step("deploy", "Deploy the function");
var deal_with_iam = true;
if (b.args) |args| {
for (args) |arg| {
if (std.mem.eql(u8, "--role", arg)) {
deal_with_iam = false;
break;
}
}
}
var iam_role: []u8 = &.{};
const iam_step = b.step("iam", "Create/Get IAM role for function");
deploy_step.dependOn(iam_step); // iam_step will either be a noop or all the stuff below
if (deal_with_iam) {
// if someone adds '-- --role arn...' to the command line, we don't
// need to do anything with the iam role. Otherwise, we'll create/
// get the IAM role and stick the name in a file in our destination
// directory to be used later
const iam_role_name_file = b.getInstallPath(exe.install_step.?.dest_dir, "iam_role_name");
iam_role = try std.fmt.allocPrint(b.allocator, "--role $(cat {s})", .{iam_role_name_file});
// defer b.allocator.free(iam_role);
if (!fileExists(iam_role_name_file)) {
// Role get/creation command
const ifstatement_fmt =
\\ if aws iam get-role --role-name lambda_basic_execution 2>&1 |grep -q NoSuchEntity; then aws iam create-role --output text --query Role.Arn --role-name lambda_basic_execution --assume-role-policy-document '{
\\ "Version": "2012-10-17",
\\ "Statement": [
\\ {
\\ "Sid": "",
\\ "Effect": "Allow",
\\ "Principal": {
\\ "Service": "lambda.amazonaws.com"
\\ },
\\ "Action": "sts:AssumeRole"
\\ }
\\ ]}' > /dev/null; fi && \
\\ aws iam attach-role-policy --policy-arn arn:aws:iam::aws:policy/AWSLambdaExecute --role-name lambda_basic_execution && \
\\ aws iam get-role --role-name lambda_basic_execution --query Role.Arn --output text >
;
const ifstatement = try std.mem.concat(b.allocator, u8, &[_][]const u8{ ifstatement_fmt, iam_role_name_file });
defer b.allocator.free(ifstatement);
iam_step.dependOn(&b.addSystemCommand(&.{ "/bin/sh", "-c", ifstatement }).step);
}
}
const function_name = b.option([]const u8, "function-name", "Function name for Lambda [zig-fn]") orelse "zig-fn";
const function_name_file = b.getInstallPath(exe.install_step.?.dest_dir, function_name);
const ifstatement = "if [ ! -f {s} ] || [ {s} -nt {s} ]; then if aws lambda get-function --function-name {s} 2>&1 |grep -q ResourceNotFoundException; then echo not found > /dev/null; {s}; else echo found > /dev/null; {s}; fi; fi";
// The architectures option was introduced in 2.2.43 released 2021-10-01
// We want to use arm64 here because it is both faster and cheaper for most
// Amazon Linux 2 is the only arm64 supported option
const not_found = "aws lambda create-function --architectures arm64 --runtime provided.al2 --function-name {s} --zip-file fileb://{s} --handler not_applicable {s} && touch {s}";
const not_found_fmt = try std.fmt.allocPrint(b.allocator, not_found, .{ function_name, function_zip, iam_role, function_name_file });
defer b.allocator.free(not_found_fmt);
const found = "aws lambda update-function-code --function-name {s} --zip-file fileb://{s} && touch {s}";
const found_fmt = try std.fmt.allocPrint(b.allocator, found, .{ function_name, function_zip, function_name_file });
defer b.allocator.free(found_fmt);
var found_final: []const u8 = undefined;
var not_found_final: []const u8 = undefined;
if (b.args) |args| {
found_final = try addArgs(b.allocator, found_fmt, args);
not_found_final = try addArgs(b.allocator, not_found_fmt, args);
} else {
found_final = found_fmt;
not_found_final = not_found_fmt;
}
const cmd = try std.fmt.allocPrint(b.allocator, ifstatement, .{
function_name_file,
std.fs.path.dirname(exe.root_src.?.path),
function_name_file,
function_name,
not_found_fmt,
found_fmt,
});
defer b.allocator.free(cmd);
// std.debug.print("{s}\n", .{cmd});
deploy_step.dependOn(package_step);
deploy_step.dependOn(&b.addSystemCommand(&.{ "/bin/sh", "-c", cmd }).step);
// TODO: Looks like IquanaTLS isn't playing nicely with payloads this small
// const payload = b.option([]const u8, "payload", "Lambda payload [{\"foo\":\"bar\"}]") orelse
// \\ {"foo": "bar"}"
// ;
const payload = b.option([]const u8, "payload", "Lambda payload [{\"foo\":\"bar\", \"baz\": \"qux\"}]") orelse
\\ {"foo": "bar", "baz": "qux"}"
;
const run_script =
\\ f=$(mktemp) && \
\\ logs=$(aws lambda invoke \
\\ --cli-binary-format raw-in-base64-out \
\\ --invocation-type RequestResponse \
\\ --function-name {s} \
\\ --payload '{s}' \
\\ --log-type Tail \
\\ --query LogResult \
\\ --output text "$f" |base64 -d) && \
\\ cat "$f" && rm "$f" && \
\\ echo && echo && echo "$logs"
;
const run_script_fmt = try std.fmt.allocPrint(b.allocator, run_script, .{ function_name, payload });
defer b.allocator.free(run_script_fmt);
const run_cmd = b.addSystemCommand(&.{ "/bin/sh", "-c", run_script_fmt });
run_cmd.step.dependOn(deploy_step);
if (b.args) |args| {
run_cmd.addArgs(args);
}
const run_step = b.step("run", "Run the app");
run_step.dependOn(&run_cmd.step);
}
}
fn fileExists(file_name: []const u8) bool {
const file = std.fs.openFileAbsolute(file_name, .{}) catch return false;
defer file.close();
return true;
}
fn addArgs(allocator: *std.mem.Allocator, original: []const u8, args: [][]const u8) ![]const u8 {
var rc = original;
for (args) |arg| {
rc = try std.mem.concat(allocator, u8, &.{ rc, " ", arg });
}
return rc;
}