31 lines
1.4 KiB
Markdown
31 lines
1.4 KiB
Markdown
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# cleanhttp
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Functions for accessing "clean" Go http.Client values
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-------------
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The Go standard library contains a default `http.Client` called
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`http.DefaultClient`. It is a common idiom in Go code to start with
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`http.DefaultClient` and tweak it as necessary, and in fact, this is
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encouraged; from the `http` package documentation:
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> The Client's Transport typically has internal state (cached TCP connections),
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so Clients should be reused instead of created as needed. Clients are safe for
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concurrent use by multiple goroutines.
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Unfortunately, this is a shared value, and it is not uncommon for libraries to
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assume that they are free to modify it at will. With enough dependencies, it
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can be very easy to encounter strange problems and race conditions due to
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manipulation of this shared value across libraries and goroutines (clients are
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safe for concurrent use, but writing values to the client struct itself is not
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protected).
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Making things worse is the fact that a bare `http.Client` will use a default
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`http.Transport` called `http.DefaultTransport`, which is another global value
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that behaves the same way. So it is not simply enough to replace
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`http.DefaultClient` with `&http.Client{}`.
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This repository provides some simple functions to get a "clean" `http.Client`
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-- one that uses the same default values as the Go standard library, but
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returns a client that does not share any state with other clients.
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