Add Multipart

config.go

@@ -2,7 +2,9 @@ package requests
 
 import (
  "compress/gzip"
+ "fmt"
  "io"
+ "mime/multipart"
  "net/http/httptest"
 )
 
@@ -43,3 +45,33 @@ func TestServerConfig(s *httptest.Server) Config {
  Client(s.Client())
  }
 }
+
+// Multipart returns a Config
+// that uses a multipart.Writer for the request body.
+// If boundary is "", a multipart boundary is chosen at random.
+// The content type of the request is set to multipart/form-data
+// with the correct boundary.
+// The multipart.Writer is automatically closed if the callback succeeds.
+func Multipart(boundary string, h func(multi *multipart.Writer) error) Config {
+ return func(rb *Builder) {
+ if boundary == "" {
+ multi := multipart.NewWriter(nil)
+ boundary = multi.Boundary()
+ }
+ rb.
+ ContentType("multipart/form-data; boundary=" + boundary).
+ BodyWriter(func(w io.Writer) error {
+ multi := multipart.NewWriter(w)
+ if err := multi.SetBoundary(boundary); err != nil {
+ return fmt.Errorf("setting boundary: %w", err)
+ }
+ if err := h(multi); err != nil {
+ return err
+ }
+ if err := multi.Close(); err != nil {
+ return fmt.Errorf("closing multipart writer: %w", err)
+ }
+ return nil
+ })
+ }
+}

config_example_test.go

@@ -4,8 +4,12 @@ import (
  "compress/gzip"
  "context"
  "fmt"
+ "io"
+ "mime/multipart"
  "net/http"
  "net/http/httptest"
+ "net/http/httputil"
+ "net/textproto"
  "strings"
 
  "github.com/carlmjohnson/requests"
@@ -100,3 +104,57 @@ func ExampleTestServerConfig() {
  // Hello, world!
  // Howdy, planet!
 }
+
+func ExampleMultipart() {
+ req, err := requests.
+ URL("http://example.com").
+ Config(requests.Multipart("abc", func(multi *multipart.Writer) error {
+ w, err := multi.CreateFormFile("file", "en.txt")
+ if err != nil {
+ return err
+ }
+ _, err = io.WriteString(w, "Hello, World!")
+ if err != nil {
+ return err
+ }
+ // Create a part with a content type
+ h := make(textproto.MIMEHeader)
+ h.Set("Content-Disposition", `form-data; name="file"; filename="jp.txt"`)
+ h.Set("Content-Type", "text/plain; utf-8")
+ w, err = multi.CreatePart(h)
+ if err != nil {
+ panic(err)
+ }
+ _, err = io.WriteString(w, "こんにちは世界!")
+ if err != nil {
+ return err
+ }
+ return nil
+ })).
+ Request(context.Background())
+ if err != nil {
+ panic(err)
+ }
+ b, err := httputil.DumpRequest(req, true)
+ if err != nil {
+ panic(err)
+ }
+
+ fmt.Println(strings.ReplaceAll(string(b), "\r", ""))
+ // Output:
+ // POST / HTTP/1.1
+ // Host: example.com
+ // Content-Type: multipart/form-data; boundary=abc
+ //
+ // --abc
+ // Content-Disposition: form-data; name="file"; filename="en.txt"
+ // Content-Type: application/octet-stream
+ //
+ // Hello, World!
+ // --abc
+ // Content-Disposition: form-data; name="file"; filename="jp.txt"
+ // Content-Type: text/plain; utf-8
+ //
+ // こんにちは世界!
+ // --abc--
+}