http.NewRequest（）解码我的URL输入

Question

When using http.NewRequest("GET", url , nil) for URLs that contain a % followed by some number, *example: https://api.deutschebahn.com/freeplan/v1/journeyDetails/356418%252F128592%252F57070%252F90271%252F80%253fstation_evaId%253D8000261) Go will encode the string to a "/" in the url. How can I avoid that?

Answer 1

Explicitly set the RawPath field of the URL struct:

req := http.NewRequest("GET", "https://api.deutschebahn.com/freeplan/v1/journeyDetails/356418%252F128592%252F57070%252F90271%252F80%253fstation_evaId%253D8000261", nil)
req.URL.RawPath = "/freeplan/v1/journeyDetails/356418%252F128592%252F57070%252F90271%252F80%253fstation_evaId%253D8000261"

This functionality is documented for this use case:

Note that the Path field is stored in decoded form: /%47%6f%2f becomes /Go/. A consequence is that it is impossible to tell which slashes in the Path were slashes in the raw URL and which were %2f. This distinction is rarely important, but when it is, code must not use Path directly.

Go 1.5 introduced the RawPath field to hold the encoded form of Path. The Parse function sets both Path and RawPath in the URL it returns, and URL's String method uses RawPath if it is a valid encoding of Path, by calling the EscapedPath method.