Jordan Delong
363d1bb20f
This change is mostly for FB internal organizational reasons. Building is not effected beyond the fact that the target now lands in hphp/hhvm/hhvm rather than src/hhvm/hhvm.
29 linhas
1.2 KiB
Plaintext
29 linhas
1.2 KiB
Plaintext
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<h2>What is a Dangling Server</h2>
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Sometimes we need to make sure on one single web page, two AJAX requests hit
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servers that are running with the same version of PHP code. This isn't always
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the case during push time. Dangling server is trying to solve this problem by
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running old instance of server on a different port for longer time before
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shutting down. This way, on new server, if a page detects that the page needs
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to be served from old version, it can simply call:
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if (dangling_server_proxy_old_request()) {
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exit;
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}
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// otherwise continue executing the page with new version
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What dangling_server_proxy_old_request() will do is to send an HTTP request to
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the local dangling server with URL, headers and POST data of current request,
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and update current response's headers and output buffer with what it gets. It
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will return false, if it failed to contact the dangling server that may have
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shut down eventually.
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Similarly, an old server can call dangling_server_proxy_new_request(), if it
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knows which servers will surely get new version of the software first:
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if (dangling_server_proxy_new_request($host)) {
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exit;
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}
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// otherwise, do something about it
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