chore: make channel optional on UploadFileV2 (#1293)

* Support no channel

* added test

* fix channel id param name

files.go

@@ -522,11 +522,13 @@ func (api *Client) completeUploadExternal(ctx context.Context, fileID string, pa
  return nil, err
  }
  values := url.Values{
- "token": {api.token},
- "files": {string(requestBytes)},
- "channel_id": {params.channel},
+ "token": {api.token},
+ "files": {string(requestBytes)},
  }
 
+ if params.channel != "" {
+ values.Add("channel_id", params.channel)
+ }
  if params.initialComment != "" {
  values.Add("initial_comment", params.initialComment)
  }
@@ -555,17 +557,15 @@ func (api *Client) UploadFileV2(params UploadFileV2Parameters) (*FileSummary, er
 // UploadFileV2 uploads file to a given slack channel using 3 steps with a custom context -
 // 1. Get an upload URL using files.getUploadURLExternal API
 // 2. Send the file as a post to the URL provided by slack
-// 3. Complete the upload and share it to the specified channel using files.completeUploadExternal
+// 3. Complete the upload and if a channel is specified, post it to the specified channel using files.completeUploadExternal
 func (api *Client) UploadFileV2Context(ctx context.Context, params UploadFileV2Parameters) (file *FileSummary, err error) {
  if params.Filename == "" {
  return nil, fmt.Errorf("file.upload.v2: filename cannot be empty")
  }
  if params.FileSize == 0 {
  return nil, fmt.Errorf("file.upload.v2: file size cannot be 0")
  }
- if params.Channel == "" {
- return nil, fmt.Errorf("file.upload.v2: channel cannot be empty")
- }
+
  u, err := api.getUploadURLExternal(ctx, getUploadURLExternalParameters{
  altText: params.AltTxt,
  fileName: params.Filename,

files_test.go

@@ -272,4 +272,13 @@ func TestUploadFileV2(t *testing.T) {
  if _, err := api.UploadFileV2(params); err != nil {
  t.Errorf("Unexpected error: %s", err)
  }
+
+ reader = bytes.NewBufferString("test no channel")
+ params = UploadFileV2Parameters{
+ Filename: "test.txt",
+ Reader: reader,
+ FileSize: 15}
+ if _, err := api.UploadFileV2(params); err != nil {
+ t.Errorf("Unexpected error: %s", err)
+ }
 }