ooni-probe-cli/internal/errorsx/dialer.go
Simone Basso 8174d88bac
refactor(i/errorsx): always use the same error reporting pattern (#478)
For consistency and also because the SafeErrorWrapperBuilder seems
to be the building pattern than the original code assumed.

New code should not use it, but I'd rather keep legacy code consistent
formally and with its own original assumptions.

In particular, it matters that SafeErrorWrapperBuilder assigns the
most relevant operation that failed. We were not doing that when we
were manually creating a new ErrWrapper.

Part of https://github.com/ooni/probe/issues/1591
2021-09-07 17:23:24 +02:00

80 lines
2.0 KiB
Go

package errorsx
import (
"context"
"net"
"github.com/ooni/probe-cli/v3/internal/netxlite/errorsx"
)
// Dialer establishes network connections.
type Dialer interface {
// DialContext behaves like net.Dialer.DialContext.
DialContext(ctx context.Context, network, address string) (net.Conn, error)
}
// ErrorWrapperDialer is a dialer that performs error wrapping. The connection
// returned by the DialContext function will also perform error wrapping.
type ErrorWrapperDialer struct {
// Dialer is the underlying dialer.
Dialer
}
// DialContext implements Dialer.DialContext.
func (d *ErrorWrapperDialer) DialContext(ctx context.Context, network, address string) (net.Conn, error) {
conn, err := d.Dialer.DialContext(ctx, network, address)
if err != nil {
return nil, SafeErrWrapperBuilder{
Classifier: errorsx.ClassifyGenericError,
Operation: errorsx.ConnectOperation,
Error: err,
}.MaybeBuild()
}
return &errorWrapperConn{Conn: conn}, nil
}
// errorWrapperConn is a net.Conn that performs error wrapping.
type errorWrapperConn struct {
// Conn is the underlying connection.
net.Conn
}
// Read implements net.Conn.Read.
func (c *errorWrapperConn) Read(b []byte) (int, error) {
count, err := c.Conn.Read(b)
if err != nil {
return 0, SafeErrWrapperBuilder{
Classifier: errorsx.ClassifyGenericError,
Operation: errorsx.ReadOperation,
Error: err,
}.MaybeBuild()
}
return count, nil
}
// Write implements net.Conn.Write.
func (c *errorWrapperConn) Write(b []byte) (int, error) {
count, err := c.Conn.Write(b)
if err != nil {
return 0, SafeErrWrapperBuilder{
Classifier: errorsx.ClassifyGenericError,
Operation: errorsx.WriteOperation,
Error: err,
}.MaybeBuild()
}
return count, nil
}
// Close implements net.Conn.Close.
func (c *errorWrapperConn) Close() error {
err := c.Conn.Close()
if err != nil {
return SafeErrWrapperBuilder{
Classifier: errorsx.ClassifyGenericError,
Operation: errorsx.CloseOperation,
Error: err,
}.MaybeBuild()
}
return nil
}