wire is a small, extendable HTTP/1.X client library for Go.
By itself it does very little, probably no more than the very least you'd expect an HTTP client to do: it sends requests and returns their responses, managing keep-alive connections in between. However, a simple middleware system allows the core transport to be extended with all kinds of additional functionality.
Middleware functions which change the functionality of an underlying transport by modifying requests as they go out, and responses as they come in. Pieces of middleware can be used to set a default User-Agent header, or enforce response timeouts, or limit the number of concurrent requests per domain, or transparently follow 3XX redirects, or attach persistent cookie jars, or... well, you get the idea.
See godoc.org for the specifics.
Let me preface this by saying that realistically, issuing HTTP requests isn't
ever going to be the bottleneck in your application (and even if it is, it'll
be due to network latency or bandwidth constraints). In any case, here are some
numbers comparing wire.Transport and http.Transport for small HTTP
round-trips over synthetic keep-alive connections.
net/http 15091 ns/op 2241 B/op 38 allocs/op (100% ops/s)
erkl/wire 4246 ns/op 524 B/op 14 allocs/op (355% ops/s)
erkl/wire ✝ 6753 ns/op 836 B/op 24 allocs/op (223% ops/s)
The benchmark marked ✝ includes a non-nil cancel channel in the RoundTrip
call. This incurs a performance penalty because all I/O has to be carried out
in separate goroutines.
Copyright (c) 2015, Erik Lundin.
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