feat(router-proxy): added support for proxy endpoint

[carloseustaquio]

Description

Implements proxy method in the Router interface that uses the proxy option of hapi.js server. Allow clients to redirect app requests to a custom backend server.

Issues Resolved

1. Add proxy option on Router #854

Check List

• New functionality includes testing.
  • All tests pass
• New functionality has been documented.
  • New functionality has javadoc added
• Commits are signed per the DCO using --signoff

[opensearch-ci-bot]

❌   DCO Check Failed 45b6937
Run ./dev-tools/signoff-check.sh remotes/origin/main 45b6937b557deec19fa568e0698655dc83d16dc6 to check locally
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[rios0rios0]

Many thanks!

[opensearch-ci-bot]

✅   DCO Check Passed 349d346

[kavilla]

Thanks for opening this will check it out as soon as possible.

[boktorbb]

Thanks for the contribution! I will check this out sometime today

[boktorbb]

@carloseustaquio would it be possible to get more information about the security implications here? More information can be added in your issue or an RFC issue can be opened for a more detailed breakdown

[boktorbb]

@carloseustaquio just checking in on the security information

[rios0rios0]

@carloseustaquio just checking in on the security information

@boktorbb-amzn we will answer you and @kavilla. At the moment we are running to deliver another feature. When we have time, we will attend to your questions. Give some time, please.

[tmarkley]

@carloseustaquio @rios0rios0 any updates? Just want to make sure this PR doesn't stay stale for too long.

[rios0rios0]

@carloseustaquio @rios0rios0 any updates? Just want to make sure this PR doesn't stay stale for too long.

We don't know the kind of security information / RFC that @boktorbb-amzn needs.
We're exposing the HAPI feature in a different way. Because in our case, we need a plugin that forward requests to another backend. We are using OSD authentication only. So, we created an interface that some backend plugins can implement, registering the routes.

With this PR, we can do:

router.proxy({
  path: '<SOME_PATH_HERE>',
  proxyPath: '<DESTINATION_PATH_HERE>',
  validate: false,
  additionalHeaders: async request => {
    <SOME AUTH STUFF>
  },
  onResponse: (_err, res, req) => {
    <SOME LOGGIN STUFF>
    return res;
  },
});

What do we need to test to give make sure that we aren't violating security?

[boktorbb]

@rios0rios0 your last comment actually addressed my concern. The PR looks good to me

[tmarkley]

So, we created an interface that some backend plugins can implement, registering the routes.

Can we add documentation for this? We should address the [ ] New functionality has been documented. step.

[kavilla]

Hello @carloseustaquio, this pull request has not had activity recently. We will close this in 7 days if no further updates. If it closes by the time you make the requested updates then please re-open the pull request. Thank you!