cmd/go/internal/modfetch: wrap errors from HTTP response bodies
The Read method on the Body returned from a net/http.Transport does
not wrap errors returned by the underlying io.Reader and returns a
bare io.ErrUnexpectedEOF if the body is shorter than the declared
Content-Length.
Since we can't feasibly add detail on the net/http side without
breaking established users, we must instead add detail on the caller
side. Since the net/http client uses url.Error for most of its own
errors, we use that same error type here.
I have not added a regression test for this change. (While it is
theoretically possible to set up a GOPROXY that returns incorrect
Content-Length headers, the change seems straightforward enough that
it isn't worth the complex test setup.)
Fixes #52727.
Change-Id: Id00b04ae4fd518148106a49188fe169aadbcce2c
Reviewed-on: https://go-review.googlesource.com/c/go/+/406675
Auto-Submit: Bryan Mills <bcmills@google.com>
Run-TryBot: Bryan Mills <bcmills@google.com>
Reviewed-by: Michael Matloob <matloob@golang.org>
TryBot-Result: Gopher Robot <gobot@golang.org>
diff --git a/src/cmd/go/internal/modfetch/proxy.go b/src/cmd/go/internal/modfetch/proxy.go
index 31d453c..4d63dd5 100644
--- a/src/cmd/go/internal/modfetch/proxy.go
+++ b/src/cmd/go/internal/modfetch/proxy.go
@@ -247,10 +247,17 @@
return nil, err
}
defer body.Close()
- return io.ReadAll(body)
+
+ b, err := io.ReadAll(body)
+ if err != nil {
+ // net/http doesn't add context to Body errors, so add it here.
+ // (See https://go.dev/issue/52727.)
+ return b, &url.Error{Op: "read", URL: pathpkg.Join(p.redactedURL, path), Err: err}
+ }
+ return b, nil
}
-func (p *proxyRepo) getBody(path string) (io.ReadCloser, error) {
+func (p *proxyRepo) getBody(path string) (r io.ReadCloser, err error) {
fullPath := pathpkg.Join(p.url.Path, path)
target := *p.url
@@ -407,7 +414,8 @@
if err != nil {
return p.versionError(version, err)
}
- body, err := p.getBody("@v/" + encVer + ".zip")
+ path := "@v/" + encVer + ".zip"
+ body, err := p.getBody(path)
if err != nil {
return p.versionError(version, err)
}
@@ -415,6 +423,9 @@
lr := &io.LimitedReader{R: body, N: codehost.MaxZipFile + 1}
if _, err := io.Copy(dst, lr); err != nil {
+ // net/http doesn't add context to Body errors, so add it here.
+ // (See https://go.dev/issue/52727.)
+ err = &url.Error{Op: "read", URL: pathpkg.Join(p.redactedURL, path), Err: err}
return p.versionError(version, err)
}
if lr.N <= 0 {
