How to get Content-Length header without downloading the resource?

[enricorotundo]

I'd need to prod a number of large files over HTTP to get their Content-Length. How to do it in resty?

I see there's a way to do a HEAD request, however while curl works:

curl -L -I https://gist.githubusercontent.com/enricorotundo/990f0ad01a50d08dfb580e4ad404870e/raw/aa6934257351a0da93f1e740c72f27128590cebc/foo_data.txt
HTTP/1.1 200 OK
[...]
Content-Length: 574
[...]

the following resty code returns nothing:

response, err := client.R().EnableTrace().Head("https://gist.githubusercontent.com/enricorotundo/990f0ad01a50d08dfb580e4ad404870e/raw/aa6934257351a0da93f1e740c72f27128590cebc/foo_data.txt")

What am I missing here?

Ah snap! How about this? 👇

resty/response.go

Lines 116 to 118 in 313f419

	// Size method returns the HTTP response size in bytes. Ya, you can relay on HTTP `Content-Length` header,
	// however it won't be good for chucked transfer/compressed response. Since Resty calculates response size
	// at the client end. You will get actual size of the http response.

[enricorotundo]

@jeevatkm Can you shed a light please? 🙃

[jeevatkm]

@enricorotundo I'm sorry for the delay. You could do -

client := resty.New()
rsp, err := client.R().EnableTrace().Head("https://gist.githubusercontent.com/enricorotundo/990f0ad01a50d08dfb580e4ad404870e/raw/aa6934257351a0da93f1e740c72f27128590cebc/foo_data.txt")
fmt.Println(err)
fmt.Println(rsp.Header().Get("Content-Length"))

Output:

574