add ca helper when run anyproxy -i

check and help to generate the root CA when run in https interception mode, and install the CA after user's confirmation (Mac only for now)

bin/rootCACheck.js

@@ -0,0 +1,33 @@
+/**
+* check if root CA exists and installed
+* will prompt to generate when needed
+*/
+
+const thunkify = require('thunkify');
+const AnyProxy = require('../proxy');
+const logUtil = require('../lib/log');
+
+const certMgr = AnyProxy.utils.certMgr;
+
+function checkRootCAExists() {
+  return certMgr.isRootCAFileExists();
+}
+
+module.exports = function *() {
+  try {
+    if (!checkRootCAExists()) {
+      logUtil.warn('Missing root CA, generating now');
+      yield thunkify(certMgr.generateRootCA)();
+      yield certMgr.trustRootCA();
+    } else {
+      const isCATrusted = yield thunkify(certMgr.ifRootCATrusted)();
+      if (!isCATrusted) {
+        logUtil.warn('ROOT CA NOT INSTALLED YET');
+        yield certMgr.trustRootCA();
+      }
+    }
+  } catch (e) {
+    console.error(e);
+  }
+};
+