ZAPI-757 VMAPI should dump core when an uncaught error is thrown

Reviewed by: Trent Mick <trentm@gmail.com>

lib/SaferJsonClient.js

@@ -96,6 +96,18 @@ SaferJsonClient.prototype.parse = function parse(req, callback) {
 
         function finish() {
             var body = Buffer.concat(chunks, len);
+
+            /*
+             * Save the original response's body in case this is the best error
+             * message we can output to the user. The responsibility to use this
+             * property is left to the user of this custom JSON client.
+             *
+             * See lib/cli.js and joyent/node-triton#30 for a concrete use case.
+             */
+            if (resErr) {
+                resErr.originalBody = body;
+            }
+
             if (res.log.trace()) {
                 res.log.trace({body: body.toString(), len: len},
                     'body received');
@@ -139,9 +151,6 @@ SaferJsonClient.prototype.parse = function parse(req, callback) {
             }
 
             // Special error handling.
-            if (resErr) {
-                resErr.message = body.toString('utf8');
-            }
             if (res && res.statusCode >= 400) {
                 // Upcast error to a RestError (if we can)
                 // Be nice and handle errors like

lib/cli.js

@@ -693,12 +693,22 @@ function main(argv) {
     cli.main(argv, function (err) {
         var exitStatus = (err ? err.exitStatus || 1 : 0);
         var showErr = (cli.showErr !== undefined ? cli.showErr : true);
+        var errHelp;
+        var errMessage;
 
         if (err && showErr) {
             var code = (err.body ? err.body.code : err.code) || err.restCode;
             if (code === 'NoCommand') {
                 /* jsl:pass */
-            } else if (err.message !== undefined) {
+            } else if (err.name === 'InternalServerError') {
+                /*
+                 * Internal server error, we want to provide a useful error
+                 * message without exposing internals.
+                 */
+                console.error('%s: internal error. Please try again later, ' +
+                    'and contact support in case the error persists.',
+                    cmdln.nameFromErr(err));
+            } else {
                 /*
                  * If the err has `body.errors`, as some Triton/SDC APIs do per
                  *      // JSSTYLED
@@ -715,17 +725,38 @@ function main(argv) {
                     });
                 }
 
+                /*
+                 * Try to find the most descriptive message to output.
+                 *
+                 * 1. If there's a message property on the error object, we
+                 * assume this is suitable to output to the user.
+                 *
+                 * 2. Otherwise, if there's an "orignalBody" property, we output
+                 * its content per joyent/node-triton#30.
+                 *
+                 * 3. We fall back to using the error's name as the error
+                 * message.
+                 */
+                if (typeof (err.message) === 'string' && err.message !== '') {
+                    errMessage = err.message;
+                } else if (err.originalBody !== undefined) {
+                    errMessage = err.originalBody.toString();
+                } else {
+                    errMessage = err.name;
+                }
+
                 console.error('%s: error%s: %s%s',
                     cmdln.nameFromErr(err),
                     (code ? format(' (%s)', code) : ''),
-                    (cli.showErrStack ? err.stack : err.message),
+                    (cli.showErrStack ? err.stack : errMessage),
                     bodyErrors);
-                var errHelp = cmdln.errHelpFromErr(err);
+            }
+
+            errHelp = cmdln.errHelpFromErr(err);
             if (errHelp) {
                 console.error(errHelp);
             }
         }
-        }
 
         /*
          * We'd like to NOT use `process.exit` because that doesn't always