61 lines
2.0 KiB
Markdown
61 lines
2.0 KiB
Markdown
go.grace [](http://travis-ci.org/daaku/go.grace)
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========
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Package grace provides a library that makes it easy to build socket
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based servers that can be gracefully terminated & restarted (that is,
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without dropping any connections).
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It provides a convenient API for HTTP servers, especially if you need to listen
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on multiple ports (for example a secondary internal only admin server).
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Additionally it is implemented using the same API as systemd providing [socket
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activation](http://0pointer.de/blog/projects/socket-activation.html)
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compatibility to also provide lazy activation of the server.
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Usage
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-----
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Demo HTTP Server with graceful termination and restart:
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https://github.com/daaku/go.grace/blob/master/gracedemo/demo.go
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1. Install the demo application
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go get github.com/daaku/go.grace/gracedemo
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1. Start it in the first terminal
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gracedemo
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This will output something like:
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2013/03/25 19:07:33 Serving [::]:48567, [::]:48568, [::]:48569 with pid 14642.
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1. In a second terminal start a slow HTTP request
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curl 'http://localhost:48567/sleep/?duration=20s'
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1. In a third terminal trigger a graceful server restart (using the pid from your output):
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kill -USR2 14642
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1. Trigger another shorter request that finishes before the earlier request:
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curl 'http://localhost:48567/sleep/?duration=0s'
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If done quickly enough, this shows the second quick request will be served by
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the new process (as indicated by the PID) while the slow first request will be
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served by the first server. It shows how the active connection was gracefully
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served before the server was shutdown. It is also showing that at one point
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both the new as well as the old server was running at the same time.
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Documentation
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-------------
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http level graceful termination and restart:
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http://godoc.org/github.com/daaku/go.grace/gracehttp
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net.Listener level graceful termination and restart:
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http://godoc.org/github.com/daaku/go.grace
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