Added proxy from env support (#885)

* added proxy from env support

* fixed package name

* fixed err wrapping

* evoid 2 err wrapping in the same format

fasthttpproxy/proxy_env.go

@@ -0,0 +1,108 @@
+package fasthttpproxy
+
+import (
+	"bufio"
+	"encoding/base64"
+	"fmt"
+	"net"
+	"net/url"
+	"sync"
+	"time"
+
+	"golang.org/x/net/http/httpproxy"
+
+	"github.com/valyala/fasthttp"
+)
+
+// FasthttpProxyHTTPDialer returns a fasthttp.DialFunc that dials using
+// the the env(HTTP_PROXY, HTTPS_PROXY and NO_PROXY) configured HTTP proxy.
+//
+// Example usage:
+//	c := &fasthttp.Client{
+//		Dial: FasthttpProxyHTTPDialer(),
+//	}
+func FasthttpProxyHTTPDialer() fasthttp.DialFunc {
+	return FasthttpProxyHTTPDialerTimeout(0)
+}
+
+// FasthttpProxyHTTPDialer returns a fasthttp.DialFunc that dials using
+// the env(HTTP_PROXY, HTTPS_PROXY and NO_PROXY) configured HTTP proxy using the given timeout.
+//
+// Example usage:
+//	c := &fasthttp.Client{
+//		Dial: FasthttpProxyHTTPDialerTimeout(time.Second * 2),
+//	}
+func FasthttpProxyHTTPDialerTimeout(timeout time.Duration) fasthttp.DialFunc {
+	proxier := httpproxy.FromEnvironment().ProxyFunc()
+
+	// map on proxy URL and its encoded auth barrier
+	authBarriers := map[*url.URL]string{}
+	authBarriersLock := sync.RWMutex{}
+
+	return func(addr string) (net.Conn, error) {
+
+		proxyURL, err := proxier(&url.URL{Host: addr})
+		if err != nil {
+			return nil, err
+		}
+
+		if proxyURL == nil {
+			if timeout == 0 {
+				return fasthttp.Dial(addr)
+			}
+			return fasthttp.DialTimeout(addr, timeout)
+		}
+
+		var conn net.Conn
+		if timeout == 0 {
+			conn, err = fasthttp.Dial(proxyURL.String())
+		} else {
+			conn, err = fasthttp.DialTimeout(proxyURL.String(), timeout)
+		}
+		if err != nil {
+			return nil, err
+		}
+
+		req := "CONNECT " + addr + " HTTP/1.1\r\n"
+		if proxyURL.User != nil {
+			authBarriersLock.RLock()
+			barrier, ok := authBarriers[proxyURL]
+			authBarriersLock.RUnlock()
+
+			if !ok {
+				barrier = base64.StdEncoding.EncodeToString([]byte(proxyURL.User.String()))
+				authBarriersLock.Lock()
+				authBarriers[proxyURL] = barrier
+				authBarriersLock.Unlock()
+			}
+
+			req += "Proxy-Authorization: Basic " + barrier + "\r\n"
+		}
+		req += "\r\n"
+
+		if _, err := conn.Write([]byte(req)); err != nil {
+			return nil, err
+		}
+
+		res := fasthttp.AcquireResponse()
+		defer fasthttp.ReleaseResponse(res)
+
+		res.SkipBody = true
+
+		if err := res.Read(bufio.NewReader(conn)); err != nil {
+			if connErr := conn.Close(); connErr != nil {
+				return nil, fmt.Errorf("conn close err %v followed by read conn err %w", connErr, err)
+			}
+			return nil, err
+		}
+		if res.Header.StatusCode() != 200 {
+			if connErr := conn.Close(); connErr != nil {
+				return nil, fmt.Errorf(
+					"conn close err %v followed by connect to proxy: code: %d body %s",
+					connErr, res.StatusCode(), string(res.Body()))
+			}
+			return nil, fmt.Errorf("could not connect to proxy: code: %d body %s", res.StatusCode(), string(res.Body()))
+		}
+		return conn, nil
+	}
+}

go.mod

@@ -7,7 +7,7 @@ require (
 	github.com/klauspost/compress v1.10.7
 	github.com/valyala/bytebufferpool v1.0.0
 	github.com/valyala/tcplisten v0.0.0-20161114210144-ceec8f93295a
-	golang.org/x/crypto v0.0.0-20190308221718-c2843e01d9a2
-	golang.org/x/net v0.0.0-20200602114024-627f9648deb9
-	golang.org/x/sys v0.0.0-20200602225109-6fdc65e7d980
+	golang.org/x/crypto v0.0.0-20200622213623-75b288015ac9
+	golang.org/x/net v0.0.0-20201016165138-7b1cca2348c0
+	golang.org/x/sys v0.0.0-20200930185726-fdedc70b468f
 )

go.sum

@@ -8,10 +8,17 @@ github.com/valyala/tcplisten v0.0.0-20161114210144-ceec8f93295a h1:0R4NLDRDZX6Jc
 github.com/valyala/tcplisten v0.0.0-20161114210144-ceec8f93295a/go.mod h1:v3UYOV9WzVtRmSR+PDvWpU/qWl4Wa5LApYYX4ZtKbio=
 golang.org/x/crypto v0.0.0-20190308221718-c2843e01d9a2 h1:VklqNMn3ovrHsnt90PveolxSbWFaJdECFbxSq0Mqo2M=
 golang.org/x/crypto v0.0.0-20190308221718-c2843e01d9a2/go.mod h1:djNgcEr1/C05ACkg1iLfiJU5Ep61QUkGW8qpdssI0+w=
-golang.org/x/net v0.0.0-20200602114024-627f9648deb9 h1:pNX+40auqi2JqRfOP1akLGtYcn15TUbkhwuCO3foqqM=
-golang.org/x/net v0.0.0-20200602114024-627f9648deb9/go.mod h1:qpuaurCH72eLCgpAm/N6yyVIVM9cpaDIP3A8BGJEC5A=
+golang.org/x/crypto v0.0.0-20200622213623-75b288015ac9 h1:psW17arqaxU48Z5kZ0CQnkZWQJsqcURM6tKiBApRjXI=
+golang.org/x/crypto v0.0.0-20200622213623-75b288015ac9/go.mod h1:LzIPMQfyMNhhGPhUkYOs5KpL4U8rLKemX1yGLhDgUto=
+golang.org/x/net v0.0.0-20190404232315-eb5bcb51f2a3/go.mod h1:t9HGtf8HONx5eT2rtn7q6eTqICYqUVnKs3thJo3Qplg=
+golang.org/x/net v0.0.0-20201016165138-7b1cca2348c0 h1:5kGOVHlq0euqwzgTC9Vu15p6fV1Wi0ArVi8da2urnVg=
+golang.org/x/net v0.0.0-20201016165138-7b1cca2348c0/go.mod h1:sp8m0HH+o8qH0wwXwYZr8TS3Oi6o0r6Gce1SSxlDquU=
 golang.org/x/sys v0.0.0-20190215142949-d0b11bdaac8a/go.mod h1:STP8DvDyc/dI5b8T5hshtkjS+E42TnysNCUPdjciGhY=
-golang.org/x/sys v0.0.0-20200323222414-85ca7c5b95cd/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
-golang.org/x/sys v0.0.0-20200602225109-6fdc65e7d980 h1:OjiUf46hAmXblsZdnoSXsEUSKU8r1UEzcL5RVZ4gO9Y=
-golang.org/x/sys v0.0.0-20200602225109-6fdc65e7d980/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
+golang.org/x/sys v0.0.0-20190412213103-97732733099d/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
+golang.org/x/sys v0.0.0-20200930185726-fdedc70b468f h1:+Nyd8tzPX9R7BWHguqsrbFdRx3WQ/1ib8I44HXV5yTA=
+golang.org/x/sys v0.0.0-20200930185726-fdedc70b468f/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
+golang.org/x/text v0.3.0 h1:g61tztE5qeGQ89tm6NTjjM9VPIm088od1l6aSorWRWg=
 golang.org/x/text v0.3.0/go.mod h1:NqM8EUOU14njkJ3fqMW+pc6Ldnwhi/IjpwHt7yyuwOQ=
+golang.org/x/text v0.3.3 h1:cokOdA+Jmi5PJGXLlLllQSgYigAEfHXJAERHVMaCc2k=
+golang.org/x/text v0.3.3/go.mod h1:5Zoc/QRtKVWzQhOtBMvqHzDpF6irO9z98xDceosuGiQ=
+golang.org/x/tools v0.0.0-20180917221912-90fa682c2a6e/go.mod h1:n7NCudcB/nEzxVGmLbDWY5pfWTLqBcC2KZ6jyYvM4mQ=