http: expose Client's Transport

This is again an intentionally minimal change.

The plan is to keep Client's zero value be a usable
client, with optional fields being added over time
(e.g. cookie manager, redirect policy, auth)

R=rsc
CC=golang-dev
https://golang.org/cl/4239044

diff --git a/src/pkg/http/client.go b/src/pkg/http/client.go
index c2e2d3eed16f39fce51b58ff852ab053a203d1d5..cbd628014eaf6bdb9728051dfbc3a7efa5bb1d62 100644 (file)
--- a/src/pkg/http/client.go
+++ b/src/pkg/http/client.go
@@ -16,10 +16,11 @@ import (
        "strings"
 )
 
-// A Client is an HTTP client.
-// It is not yet possible to create custom Clients; use DefaultClient.
+// A Client is an HTTP client. Its zero value (DefaultClient) is a usable client
+// that uses DefaultTransport.
+// Client is not yet very configurable.
 type Client struct {
-       transport ClientTransport // if nil, DefaultTransport is used
+       Transport ClientTransport // if nil, DefaultTransport is used
 }
 
 // DefaultClient is the default Client and is used by Get, Head, and Post.
@@ -87,15 +88,15 @@ func matchNoProxy(addr string) bool {
 // Do sends an HTTP request and returns an HTTP response, following
 // policy (e.g. redirects, cookies, auth) as configured on the client.
 //
-// Callers should close resp.Body when done reading it.
+// Callers should close resp.Body when done reading from it.
 //
 // Generally Get, Post, or PostForm will be used instead of Do.
 func (c *Client) Do(req *Request) (resp *Response, err os.Error) {
-       return send(req, c.transport)
+       return send(req, c.Transport)
 }
 
 
-// send issues an HTTP request.  Caller should close resp.Body when done reading it.
+// send issues an HTTP request.  Caller should close resp.Body when done reading from it.
 //
 // TODO: support persistent connections (multiple requests on a single connection).
 // send() method is nonpublic because, when we refactor the code for persistent
@@ -103,6 +104,10 @@ func (c *Client) Do(req *Request) (resp *Response, err os.Error) {
 func send(req *Request, t ClientTransport) (resp *Response, err os.Error) {
        if t == nil {
                t = DefaultTransport
+               if t == nil {
+                       err = os.NewError("no http.Client.Transport or http.DefaultTransport")
+                       return
+               }
        }
        info := req.URL.RawUserinfo
        if len(info) > 0 {
@@ -138,7 +143,7 @@ func shouldRedirect(statusCode int) bool {
 // finalURL is the URL from which the response was fetched -- identical to the
 // input URL unless redirects were followed.
 //
-// Caller should close r.Body when done reading it.
+// Caller should close r.Body when done reading from it.
 //
 // Get is a convenience wrapper around DefaultClient.Get.
 func Get(url string) (r *Response, finalURL string, err os.Error) {
@@ -156,7 +161,7 @@ func Get(url string) (r *Response, finalURL string, err os.Error) {
 // finalURL is the URL from which the response was fetched -- identical to the
 // input URL unless redirects were followed.
 //
-// Caller should close r.Body when done reading it.
+// Caller should close r.Body when done reading from it.
 func (c *Client) Get(url string) (r *Response, finalURL string, err os.Error) {
        // TODO: if/when we add cookie support, the redirected request shouldn't
        // necessarily supply the same cookies as the original.
@@ -183,7 +188,7 @@ func (c *Client) Get(url string) (r *Response, finalURL string, err os.Error) {
                        break
                }
                url = req.URL.String()
-               if r, err = send(&req, c.transport); err != nil {
+               if r, err = send(&req, c.Transport); err != nil {
                        break
                }
                if shouldRedirect(r.StatusCode) {
@@ -205,7 +210,7 @@ func (c *Client) Get(url string) (r *Response, finalURL string, err os.Error) {
 
 // Post issues a POST to the specified URL.
 //
-// Caller should close r.Body when done reading it.
+// Caller should close r.Body when done reading from it.
 //
 // Post is a wrapper around DefaultClient.Post
 func Post(url string, bodyType string, body io.Reader) (r *Response, err os.Error) {
@@ -214,7 +219,7 @@ func Post(url string, bodyType string, body io.Reader) (r *Response, err os.Erro
 
 // Post issues a POST to the specified URL.
 //
-// Caller should close r.Body when done reading it.
+// Caller should close r.Body when done reading from it.
 func (c *Client) Post(url string, bodyType string, body io.Reader) (r *Response, err os.Error) {
        var req Request
        req.Method = "POST"
@@ -232,13 +237,13 @@ func (c *Client) Post(url string, bodyType string, body io.Reader) (r *Response,
                return nil, err
        }
 
-       return send(&req, c.transport)
+       return send(&req, c.Transport)
 }
 
 // PostForm issues a POST to the specified URL, 
 // with data's keys and values urlencoded as the request body.
 //
-// Caller should close r.Body when done reading it.
+// Caller should close r.Body when done reading from it.
 //
 // PostForm is a wrapper around DefaultClient.PostForm
 func PostForm(url string, data map[string]string) (r *Response, err os.Error) {
@@ -248,7 +253,7 @@ func PostForm(url string, data map[string]string) (r *Response, err os.Error) {
 // PostForm issues a POST to the specified URL, 
 // with data's keys and values urlencoded as the request body.
 //
-// Caller should close r.Body when done reading it.
+// Caller should close r.Body when done reading from it.
 func (c *Client) PostForm(url string, data map[string]string) (r *Response, err os.Error) {
        var req Request
        req.Method = "POST"
@@ -268,7 +273,7 @@ func (c *Client) PostForm(url string, data map[string]string) (r *Response, err
                return nil, err
        }
 
-       return send(&req, c.transport)
+       return send(&req, c.Transport)
 }
 
 // TODO: remove this function when PostForm takes a multimap.
@@ -294,7 +299,7 @@ func (c *Client) Head(url string) (r *Response, err os.Error) {
        if req.URL, err = ParseURL(url); err != nil {
                return
        }
-       return send(&req, c.transport)
+       return send(&req, c.Transport)
 }
 
 type nopCloser struct {

diff --git a/src/pkg/http/client_test.go b/src/pkg/http/client_test.go
index a541ffc08edd2a072fef19998ae77b7953cd8444..1b0fe0350910c8c1c2589ededf8915e497bc96cf 100644 (file)
--- a/src/pkg/http/client_test.go
+++ b/src/pkg/http/client_test.go
@@ -51,7 +51,7 @@ func (t *recordingTransport) Do(req *Request) (resp *Response, err os.Error) {
 
 func TestGetRequestFormat(t *testing.T) {
        tr := &recordingTransport{}
-       client := &Client{transport: tr}
+       client := &Client{Transport: tr}
        url := "http://dummy.faketld/"
        client.Get(url) // Note: doesn't hit network
        if tr.req.Method != "GET" {