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How do I Implement Gateway Service something similar to Oracle API gateway Using Java and Java based Open Source frameworks only?

• wanted to Implement API Management Using only Java and Java Based Open Source frameworks. Need help how to go about it. I need following things that really make me ready to go " Blue -print and Sample Source Code or any Completely Open Source API management tool that support almost feature Identical to Oracle API gateway or Intel API management or apigee Application available in todays world's". We do not have budget to buy any commercial product from market, we wanted to build our own. Please provide us valuable guidance to go ahead to create an API Management Platform just using Java and Java Based Open Source frameworks

• Answer:

  Full disclosure: I used to work for http://layer7.com/ and played a major role in designing their core gateway product, so don't expect too much objectivity. :) Building your own will take a surprisingly long time, and if you're working for North American software engineer wages, that translates to a surprisingly large amount of money.  I'd say it's pretty likely to exceed what it would cost to buy something off-the-shelf. Try some of the SaaS services first, see if they meet your needs.  On the other hand, if your labour costs are significantly cheaper, and you're not on a tight timeline, here's what I would do, assuming you want to build a gateway, not a purely advisory authentication/authorization system*. Evaluate https://camel.apache.org/how-does-camel-compare-to-mule.html, https://www.mulesoft.com/resources/esb/mule-vs-camel-comparison, https://www.jboss.org/jbossesb and any other competitors that come to mind; see whether any one of them provides a more suitable starting point.  They're all essentially everything-to-everything connectors. Consider using https://www.jboss.org/drools/ to implement your policy logic instead of hard-coding things. Mule and Camel both have Drools support. For authentication and identity management, LDAP can be an immense pain in the ass, but it's usually better than building your own identity provider, and existing J2EE-land tooling will already support it well. I've used OpenLDAP, but that was a long time ago so I don't know if anything else that's come along since is any better. Have fun! :) * In case you're not clear on the difference, a gateway actually proxies the traffic if it meets the policy requirements (and can also mediate between different transports, apply transformations, mux/demux between multiple endpoints...); an auth/authz system merely advises some other system on whether or not to do the proxying.