func ExampleLBClient() {
// Requests will be spread among these servers.
servers := []string{
"google.com:80",
"foobar.com:8080",
"127.0.0.1:123",
}
// Prepare clients for each server
var lbc fasthttp.LBClient
for _, addr := range servers {
c := &fasthttp.HostClient{
Addr: addr,
}
lbc.Clients = append(lbc.Clients, c)
}
// Send requests to load-balanced servers
var req fasthttp.Request
var resp fasthttp.Response
for i := 0; i < 10; i++ {
url := fmt.Sprintf("http://abcedfg/foo/bar/%d", i)
req.SetRequestURI(url)
if err := lbc.Do(&req, &resp); err != nil {
log.Fatalf("Error when sending request: %s", err)
}
if resp.StatusCode() != fasthttp.StatusOK {
log.Fatalf("unexpected status code: %d. Expecting %d", resp.StatusCode(), fasthttp.StatusOK)
}
useResponseBody(resp.Body())
}
}
func (c *Client) run() {
var resp fasthttp.Response
r := new(fasthttp.Request)
c.request.CopyTo(r)
for range c.Jobsch {
s := time.Now()
err := c.Do(r, &resp)
if err != nil {
if err == fasthttp.ErrTimeout {
timeouts.Inc()
}
errors.Inc()
c.withErrorMessage(err.Error()).Inc()
}
sc := resp.StatusCode()
if c.successStatusCode == sc {
requestSuccess.Inc()
}
c.withStatusCode(sc).Inc()
requestDuration.Observe(float64(time.Since(s).Seconds()))
requestSum.Inc()
}
}
func fetchFromUpstream(h *fasthttp.RequestHeader, key []byte) *ybc.Item {
upstreamUrl := fmt.Sprintf("%s://%s%s", *upstreamProtocol, *upstreamHost, h.RequestURI())
var req fasthttp.Request
req.SetRequestURI(upstreamUrl)
var resp fasthttp.Response
err := upstreamClient.Do(&req, &resp)
if err != nil {
logRequestError(h, "Cannot make request for [%s]: [%s]", key, err)
return nil
}
if resp.StatusCode() != fasthttp.StatusOK {
logRequestError(h, "Unexpected status code=%d for the response [%s]", resp.StatusCode(), key)
return nil
}
contentType := string(resp.Header.ContentType())
if contentType == "" {
contentType = "application/octet-stream"
}
body := resp.Body()
contentLength := len(body)
itemSize := contentLength + len(contentType) + 1
txn, err := cache.NewSetTxn(key, itemSize, ybc.MaxTtl)
if err != nil {
logRequestError(h, "Cannot start set txn for response [%s], itemSize=%d: [%s]", key, itemSize, err)
return nil
}
if err = storeContentType(h, txn, contentType); err != nil {
txn.Rollback()
return nil
}
n, err := txn.Write(body)
if err != nil {
logRequestError(h, "Cannot read response [%s] body with size=%d to cache: [%s]", key, contentLength, err)
txn.Rollback()
return nil
}
if n != contentLength {
logRequestError(h, "Unexpected number of bytes copied=%d from response [%s] to cache. Expected %d", n, key, contentLength)
txn.Rollback()
return nil
}
item, err := txn.CommitItem()
if err != nil {
logRequestError(h, "Cannot commit set txn for response [%s], size=%d: [%s]", key, contentLength, err)
return nil
}
atomic.AddInt64(&stats.BytesReadFromUpstream, int64(n))
return item
}
func runRequests(b *testing.B, pb *testing.PB, c *fasthttp.HostClient) {
var req fasthttp.Request
req.SetRequestURI("http://foo.bar/baz")
var resp fasthttp.Response
for pb.Next() {
if err := c.Do(&req, &resp); err != nil {
b.Fatalf("unexpected error: %s", err)
}
if resp.StatusCode() != fasthttp.StatusOK {
b.Fatalf("unexpected status code: %d. Expecting %d", resp.StatusCode(), fasthttp.StatusOK)
}
}
}
