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1.request

\n
var request = require( 'request' );\napp.all( '/proxy/*', function( req, res ){\n    req.pipe( request({\n        url: config.backendUrl + req.params[0],\n        qs: req.query,\n        method: req.method\n    })).pipe( res );\n});
\n

It works fine if remote host is available, but if remote host is unavailable the whole node server crashes with unhandled exception

\n
app.all( '/proxy/*', function( req, res ){\n  req.pipe( request({\n      url: config.backendUrl + req.params[0],\n      qs: req.query,\n      method: req.method\n  }, function(error, response, body){\n    if (error.code === 'ECONNREFUSED'){\n      console.error('Refused connection');\n    } else { \n      throw error; \n    }\n  })).pipe( res );\n});
\n

You should actually try to prevent the ECONNREFUSED exception from becoming uncaught:

\n
var request = require( 'request' );\napp.all( '/proxy/*', function( req, res ){\n    req.pipe( request({\n        url: config.backendUrl + req.params[0],\n        qs: req.query,\n        method: req.method\n    }))\n    .on('error', err => {\n        const msg = 'Error on connecting to the webservice.';\n        console.error(msg, err);\n        res.status(500).send(msg);\n    })\n    .pipe( res );\n});
\n

If you get an actual uncaught exception, then you should just let the application die.

\n
    \n
  1. If you store any state on your servers that you don’t want to loose when a server is down then store your state on the two specific database servers - a master and a replica. If you don’t know which database server to pick then let me know and I will ask you additional questions to help.
    2. \n
  2. If a client code that is using your servers is under your control then implement all the fault tolerance logic in there. The simplest way of doing this is the “round robin” - you connect to a random server until you find a server which serves your request. Google “round robin” for more details.
    3. \n
  3. If a client code is not under your control then you should use BGP load balancing. The main idea of that is that once a server is down another server gets the IP address of the first one, such as on a client side everything is perfect. For more details just google “bgp load balancing”.
    4. \n
\n

2.blueburd

\n

3.domain

\n

4.cluster

\n

5.forever

\n

6.pm2

\n

7.morgan

\n

8.bunyan

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