stdio jsonrpc server npm package (#5332)

- [x] figgure out how to build the packages (that it installs native
optional package automatically)
- [X] Make the gluecode
- [x] expose both the lowerlevel api that desktop uses (~~send objects
and receive objects~~, getting path of rpc-server is enough)
  - [X] and the higher level api needed for bots (jsonrpc client)
  - [X] typescript types
- [x] automatically pick the right binary from npm or allow getting it
from env var, or give out an error (throw error)
- [x] find out how to dev locally (use local built core in dc desktop) -
there is the question of how to link the typescript client and the task
to add a search in the cargo target folder for a debug build or a
different way, find out some good flow that we can use and document for
dc desktop + locally built core development
- [x] build the packages in ci
- [x] fix that deltachat-rpc-server is not executable

postponed:
- [ ] publish from ci
   - [ ] add key/token to deploy to npm 

Closes #4694

## Related prs
- https://github.com/deltachat-bot/echo/pull/69
- https://github.com/deltachat/deltachat-desktop/pull/3567

---------

Co-authored-by: link2xt <link2xt@testrun.org>

deltachat-rpc-server/npm-package/index.js

@@ -0,0 +1,143 @@
+//@ts-check
+import { execFile, spawn } from "node:child_process";
+import { stat, readdir } from "node:fs/promises";
+import os from "node:os";
+import { join, basename } from "node:path";
+import process from "node:process";
+import { promisify } from "node:util";
+import {
+  ENV_VAR_NAME,
+  PATH_EXECUTABLE_NAME,
+  SKIP_SEARCH_IN_PATH,
+} from "./src/const.js";
+import {
+  ENV_VAR_LOCATION_NOT_FOUND,
+  FAILED_TO_START_SERVER_EXECUTABLE,
+  NPM_NOT_FOUND_SUPPORTED_PLATFORM_ERROR,
+  NPM_NOT_FOUND_UNSUPPORTED_PLATFORM_ERROR,
+} from "./src/errors.js";
+
+// Because this is not compiled by typescript, esm needs this stuff (` with { type: "json" };`,
+// nodejs still complains about it being experimental, but deno also uses it, so treefit bets taht it will become standard)
+import package_json from "./package.json" with { type: "json" };
+import { createRequire } from "node:module";
+
+// exports
+// - [ ] a raw starter that has a stdin/out handle thingie like desktop uses
+// - [X] a function that already wraps the stdio handle from above into the deltachat jsonrpc bindings
+
+function findRPCServerInNodeModules() {
+  const arch = os.arch();
+  const operating_system = process.platform;
+  const package_name = `@deltachat/stdio-rpc-server-${operating_system}-${arch}`;
+  try {
+    const { resolve } = createRequire(import.meta.url);
+    return resolve(package_name);
+  } catch (error) {
+    console.debug("findRpcServerInNodeModules", error);
+    if (Object.keys(package_json.optionalDependencies).includes(package_name)) {
+      throw new Error(NPM_NOT_FOUND_SUPPORTED_PLATFORM_ERROR(package_name));
+    } else {
+      throw new Error(NPM_NOT_FOUND_UNSUPPORTED_PLATFORM_ERROR());
+    }
+  }
+}
+
+/** @type {import("./index").FnTypes.getRPCServerPath} */
+export async function getRPCServerPath(
+  options = { skipSearchInPath: false, disableEnvPath: false }
+) {
+  // @TODO: improve confusing naming of these options
+  const { skipSearchInPath, disableEnvPath } = options;
+  // 1. check if it is set as env var
+  if (process.env[ENV_VAR_NAME] && !disableEnvPath) {
+    try {
+      if (!(await stat(process.env[ENV_VAR_NAME])).isFile()) {
+        throw new Error(
+          `expected ${ENV_VAR_NAME} to point to the deltachat-rpc-server executable`
+        );
+      }
+    } catch (error) {
+      throw new Error(ENV_VAR_LOCATION_NOT_FOUND());
+    }
+    return process.env[ENV_VAR_NAME];
+  }
+
+  // 2. check if it can be found in PATH
+  if (!process.env[SKIP_SEARCH_IN_PATH] && !skipSearchInPath) {
+    const exec = promisify(execFile);
+
+    const { stdout: executable } =
+      os.platform() !== "win32"
+        ? await exec("command", ["-v", PATH_EXECUTABLE_NAME])
+        : await exec("where", [PATH_EXECUTABLE_NAME]);
+
+    // by just trying to execute it and then use "command -v deltachat-rpc-server" (unix) or "where deltachat-rpc-server" (windows) to get the path to the executable
+    if (executable.length > 1) {
+      // test if it is the right version
+      try {
+        // for some unknown reason it is in stderr and not in stdout
+        const { stderr } = await promisify(execFile)(executable, ["--version"]);
+        const version = stderr.slice(0, stderr.indexOf("\n"));
+        if (package_json.version !== version) {
+          throw new Error(
+            `version mismatch: (npm package: ${package_json.version})  (installed ${PATH_EXECUTABLE_NAME} version: ${version})`
+          );
+        } else {
+          return executable;
+        }
+      } catch (error) {
+        console.error(
+          "Found executable in PATH, but there was an error: " + error
+        );
+        console.error("So falling back to using prebuild...");
+      }
+    }
+  }
+  // 3. check for prebuilds
+
+  return findRPCServerInNodeModules();
+}
+
+import { StdioDeltaChat } from "@deltachat/jsonrpc-client";
+
+/** @type {import("./index").FnTypes.startDeltaChat} */
+export async function startDeltaChat(directory, options) {
+  const pathToServerBinary = await getRPCServerPath(options);
+  const server = spawn(pathToServerBinary, {
+    env: {
+      RUST_LOG: process.env.RUST_LOG || "info",
+      DC_ACCOUNTS_PATH: directory,
+    },
+  });
+
+  server.on("error", (err) => {
+    throw new Error(FAILED_TO_START_SERVER_EXECUTABLE(pathToServerBinary, err));
+  });
+  let shouldClose = false;
+
+  server.on("exit", () => {
+    if (shouldClose) {
+      return;
+    }
+    throw new Error("Server quit");
+  });
+
+  server.stderr.pipe(process.stderr);
+
+  /** @type {import('./index').DeltaChatOverJsonRpcServer} */
+  //@ts-expect-error
+  const dc = new StdioDeltaChat(server.stdin, server.stdout, true);
+
+  dc.shutdown = async () => {
+    shouldClose = true;
+    if (!server.kill()) {
+      console.log("server termination failed");
+    }
+  };
+
+  //@ts-expect-error
+  dc.pathToServerBinary = pathToServerBinary;
+
+  return dc;
+}