// GetResponseWriter returns the http.ResponseWriter from the provided
// context. If not present, ErrNoResponseWriterContext is returned. The
// returned instance provides instrumentation in the context.
func GetResponseWriter(ctx dctx.Context) (http.ResponseWriter, error) {
v := ctx.Value("http.response")
rw, ok := v.(http.ResponseWriter)
if !ok || rw == nil {
return nil, ErrNoResponseWriterContext
}
return rw, nil
}
// WithRequest places the request on the context. The context of the request
// is assigned a unique id, available at "http.request.id". The request itself
// is available at "http.request". Other common attributes are available under
// the prefix "http.request.". If a request is already present on the context,
// this method will panic.
func WithRequest(ctx dctx.Context, r *http.Request) dctx.Context {
if ctx.Value("http.request") != nil {
// NOTE(stevvooe): This needs to be considered a programming error. It
// is unlikely that we'd want to have more than one request in
// context.
panic("only one request per context")
}
return &httpRequestContext{
Context: ctx,
startedAt: time.Now(),
id: uuid.Generate().String(),
r: r,
}
}
// GetRequest returns the http request in the given context. Returns
// ErrNoRequestContext if the context does not have an http request associated
// with it.
func GetRequest(ctx dctx.Context) (*http.Request, error) {
if r, ok := ctx.Value("http.request").(*http.Request); r != nil && ok {
return r, nil
}
return nil, ErrNoRequestContext
}