first commit

grafana/dashboards/requests/node_modules/sync-rpc/lib/index.js

@@ -0,0 +1,181 @@
+'use strict';
+
+const path = require('path');
+const spawn = require('child_process').spawn;
+const spawnSync = require('child_process').spawnSync;
+const JSON = require('./json-buffer');
+
+const host = '127.0.0.1';
+function nodeNetCatSrc(port, input) {
+  return (
+    "var c=require('net').connect(" +
+    port +
+    ",'127.0.0.1',()=>{c.pipe(process.stdout);c.end(" +
+    JSON.stringify(input)
+      .replace(/\u2028/g, '\\u2028')
+      .replace(/\u2029/g, '\\u2029') +
+    ')})'
+  );
+}
+
+const FUNCTION_PRIORITY = [nativeNC, nodeNC];
+
+let started = false;
+const configuration = {port: null, fastestFunction: null};
+function start() {
+  if (!spawnSync) {
+    throw new Error(
+      'Sync-request requires node version 0.12 or later.  If you need to use it with an older version of node\n' +
+        'you can `npm install sync-request@2.2.0`, which was the last version to support older versions of node.'
+    );
+  }
+  const port = findPort();
+  const p = spawn(process.execPath, [require.resolve('./worker'), port], {
+    stdio: 'inherit',
+    windowsHide: true,
+  });
+  p.unref();
+  process.on('exit', () => {
+    p.kill();
+  });
+  waitForAlive(port);
+  const fastestFunction = getFastestFunction(port);
+  configuration.port = port;
+  configuration.fastestFunction = fastestFunction;
+  started = true;
+}
+
+function findPort() {
+  const findPortResult = spawnSync(
+    process.execPath,
+    [require.resolve('./find-port')],
+    {
+      windowsHide: true,
+    }
+  );
+  if (findPortResult.error) {
+    if (typeof findPortResult.error === 'string') {
+      throw new Error(findPortResult.error);
+    }
+    throw findPortResult.error;
+  }
+  if (findPortResult.status !== 0) {
+    throw new Error(
+      findPortResult.stderr.toString() ||
+        'find port exited with code ' + findPortResult.status
+    );
+  }
+  const portString = findPortResult.stdout.toString('utf8').trim();
+  if (!/^[0-9]+$/.test(portString)) {
+    throw new Error('Invalid port number string returned: ' + portString);
+  }
+  return +portString;
+}
+
+function waitForAlive(port) {
+  let response = null;
+  let err = null;
+  let timeout = Date.now() + 10000;
+  while (response !== 'pong' && Date.now() < timeout) {
+    const result = nodeNC(port, 'ping\r\n');
+    response = result.stdout && result.stdout.toString();
+    err = result.stderr && result.stderr.toString();
+  }
+  if (response !== 'pong') {
+    throw new Error(
+      'Timed out waiting for sync-rpc server to start (it should respond with "pong" when sent "ping"):\n\n' +
+        err +
+        '\n' +
+        response
+    );
+  }
+}
+
+function nativeNC(port, input) {
+  return spawnSync('nc', [host, port], {
+    input: input,
+    windowsHide: true,
+    maxBuffer: Infinity,
+  });
+}
+
+function nodeNC(port, input) {
+  const src = nodeNetCatSrc(port, input);
+  if (src.length < 1000) {
+    return spawnSync(process.execPath, ['-e', src], {
+      windowsHide: true,
+      maxBuffer: Infinity,
+    });
+  } else {
+    return spawnSync(process.execPath, [], {
+      input: src,
+      windowsHide: true,
+      maxBuffer: Infinity,
+    });
+  }
+}
+
+function test(fn, port) {
+  const result = fn(port, 'ping\r\n');
+  const response = result.stdout && result.stdout.toString();
+  return response === 'pong';
+}
+
+function getFastestFunction(port) {
+  for (let i = 0; i < FUNCTION_PRIORITY.length; i++) {
+    if (test(FUNCTION_PRIORITY[i], port)) {
+      return FUNCTION_PRIORITY[i];
+    }
+  }
+}
+
+function sendMessage(input) {
+  if (!started) start();
+  const res = configuration.fastestFunction(
+    configuration.port,
+    JSON.stringify(input) + '\r\n'
+  );
+  try {
+    return JSON.parse(res.stdout.toString('utf8'));
+  } catch (ex) {
+    if (res.error) {
+      if (typeof res.error === 'string') res.error = new Error(res.error);
+      throw res.error;
+    }
+    if (res.status !== 0) {
+      throw new Error(
+        configuration.fastestFunction.name +
+          ' failed:\n' +
+          (res.stdout && res.stdout.toString()) +
+          '\n' +
+          (res.stderr && res.stderr.toString())
+      );
+    }
+    throw new Error(
+      configuration.fastestFunction.name +
+        ' failed:\n' +
+        (res.stdout && res.stdout).toString() +
+        '\n' +
+        (res.stderr && res.stderr).toString()
+    );
+  }
+}
+function extractValue(msg) {
+  if (!msg.s) {
+    const error = new Error(msg.v.message);
+    error.code = msg.v.code;
+    throw error;
+  }
+  return msg.v;
+}
+
+function createClient(filename, args) {
+  const id = extractValue(sendMessage({t: 1, f: filename, a: args}));
+  return function(args) {
+    return extractValue(sendMessage({t: 0, i: id, a: args}));
+  };
+}
+createClient.FUNCTION_PRIORITY = FUNCTION_PRIORITY;
+createClient.configuration = configuration;
+
+module.exports = createClient;