Youtube Channel list brandingSettings empty with forUsername but not id

Question

Using the Youtube Data API's Channels:list with the brandingSettings part works when using the id filter but not the forUsername filter for me.

For example, GET https://www.googleapis.com/youtube/v3/channels?part=brandingSettings&forUsername=h3h3Productions&key={YOUR_API_KEY} results in the following, which is missing brandSettings:

{
 "kind": "youtube#channelListResponse",
 "etag": "\"0KG1mRN7bm3nResDPKHQZpg5-do/Qagk6ayL_umilQ398UZyAHwxK_g\"",
 "pageInfo": {
  "totalResults": 1,
  "resultsPerPage": 5
 },
 "items": [
  {
   "kind": "youtube#channel",
   "etag": "\"0KG1mRN7bm3nResDPKHQZpg5-do/tTzKQvYs0Y2GpqN2wqgudxB2TnQ\"",
   "id": "UCDWIvJwLJsE4LG1Atne2blQ"
  }
 ]
}

But GET https://www.googleapis.com/youtube/v3/channels?part=brandingSettings&id=UCDWIvJwLJsE4LG1Atne2blQ&key={YOUR_API_KEY} (which you'll notice uses the ID of the same user), leaves it intact:

{
 "kind": "youtube#channelListResponse",
 "etag": "\"0KG1mRN7bm3nResDPKHQZpg5-do/2ZOHdezDOZFRR9xisREY04R4OOg\"",
 "pageInfo": {
  "totalResults": 1,
  "resultsPerPage": 1
 },
 "items": [
  {
   "kind": "youtube#channel",
   "etag": "\"0KG1mRN7bm3nResDPKHQZpg5-do/58_5G5_Hi-64MiC8m5NC76sDIOA\"",
   "id": "UCDWIvJwLJsE4LG1Atne2blQ",
   "brandingSettings": {
    "channel": {
     "title": "h3h3Productions",
     "description": "Wacky, zany, goofy comedy. ",
     "keywords": "comedy humor satire parody funny sketch \"sketch comedy\" reaction \"reaction video\" review h3h3 h3h3productions",
     "showRelatedChannels": true,
     "showBrowseView": true,
     "featuredChannelsTitle": "SECOND CHANNEL",
     "featuredChannelsUrls": [
      "UC7pp40MU_6rLK5pvJYG3d0Q"
     ],
     "unsubscribedTrailer": "tVaAv0cPRok",
     "profileColor": "#000000",
     "country": "US"
    },
    "image": {
     "bannerImageUrl": "https://yt3.ggpht.com/-DFbgqVWqgm8/VDV_M-xkJtI/AAAAAAAAAOE/zQeoRrTR-qA/w1060-fcrop64=1,00005a57ffffa5a8-nd/youtube%2Bnew%2Bbanner14.jpg",
     "bannerMobileImageUrl": "https://yt3.ggpht.com/-DFbgqVWqgm8/VDV_M-xkJtI/AAAAAAAAAOE/zQeoRrTR-qA/w640-fcrop64=1,32b75a57cd48a5a8-nd/youtube%2Bnew%2Bbanner14.jpg",
     "bannerTabletLowImageUrl": "https://yt3.ggpht.com/-DFbgqVWqgm8/VDV_M-xkJtI/AAAAAAAAAOE/zQeoRrTR-qA/w1138-fcrop64=1,00005a57ffffa5a8-nd/youtube%2Bnew%2Bbanner14.jpg",
     "bannerTabletImageUrl": "https://yt3.ggpht.com/-DFbgqVWqgm8/VDV_M-xkJtI/AAAAAAAAAOE/zQeoRrTR-qA/w1707-fcrop64=1,00005a57ffffa5a8-nd/youtube%2Bnew%2Bbanner14.jpg",
     "bannerTabletHdImageUrl": "https://yt3.ggpht.com/-DFbgqVWqgm8/VDV_M-xkJtI/AAAAAAAAAOE/zQeoRrTR-qA/w2276-fcrop64=1,00005a57ffffa5a8-nd/youtube%2Bnew%2Bbanner14.jpg",
     "bannerTabletExtraHdImageUrl": "https://yt3.ggpht.com/-DFbgqVWqgm8/VDV_M-xkJtI/AAAAAAAAAOE/zQeoRrTR-qA/w2560-fcrop64=1,00005a57ffffa5a8-nd/youtube%2Bnew%2Bbanner14.jpg",
     "bannerMobileLowImageUrl": "https://yt3.ggpht.com/-DFbgqVWqgm8/VDV_M-xkJtI/AAAAAAAAAOE/zQeoRrTR-qA/w320-fcrop64=1,32b75a57cd48a5a8-nd/youtube%2Bnew%2Bbanner14.jpg",
     "bannerMobileMediumHdImageUrl": "https://yt3.ggpht.com/-DFbgqVWqgm8/VDV_M-xkJtI/AAAAAAAAAOE/zQeoRrTR-qA/w960-fcrop64=1,32b75a57cd48a5a8-nd/youtube%2Bnew%2Bbanner14.jpg",
     "bannerMobileHdImageUrl": "https://yt3.ggpht.com/-DFbgqVWqgm8/VDV_M-xkJtI/AAAAAAAAAOE/zQeoRrTR-qA/w1280-fcrop64=1,32b75a57cd48a5a8-nd/youtube%2Bnew%2Bbanner14.jpg",
     "bannerMobileExtraHdImageUrl": "https://yt3.ggpht.com/-DFbgqVWqgm8/VDV_M-xkJtI/AAAAAAAAAOE/zQeoRrTR-qA/w1440-fcrop64=1,32b75a57cd48a5a8-nd/youtube%2Bnew%2Bbanner14.jpg",
     "bannerTvImageUrl": "https://yt3.ggpht.com/-DFbgqVWqgm8/VDV_M-xkJtI/AAAAAAAAAOE/zQeoRrTR-qA/w2120-fcrop64=1,00000000ffffffff-nd/youtube%2Bnew%2Bbanner14.jpg",
     "bannerTvLowImageUrl": "https://yt3.ggpht.com/-DFbgqVWqgm8/VDV_M-xkJtI/AAAAAAAAAOE/zQeoRrTR-qA/w854-fcrop64=1,00000000ffffffff-nd/youtube%2Bnew%2Bbanner14.jpg",
     "bannerTvMediumImageUrl": "https://yt3.ggpht.com/-DFbgqVWqgm8/VDV_M-xkJtI/AAAAAAAAAOE/zQeoRrTR-qA/w1280-fcrop64=1,00000000ffffffff-nd/youtube%2Bnew%2Bbanner14.jpg",
     "bannerTvHighImageUrl": "https://yt3.ggpht.com/-DFbgqVWqgm8/VDV_M-xkJtI/AAAAAAAAAOE/zQeoRrTR-qA/w1920-fcrop64=1,00000000ffffffff-nd/youtube%2Bnew%2Bbanner14.jpg"
    },
    "hints": [
     {
      "property": "channel.banner.mobile.medium.image.url",
      "value": "https://yt3.ggpht.com/-DFbgqVWqgm8/VDV_M-xkJtI/AAAAAAAAAOE/zQeoRrTR-qA/w640-fcrop64=1,32b75a57cd48a5a8-nd/youtube%2Bnew%2Bbanner14.jpg"
     },
     {
      "property": "channel.banner.image_height.int",
      "value": "0"
     },
     {
      "property": "channel.featured_tab.template.string",
      "value": "Everything"
     },
     {
      "property": "channel.modules.show_comments.bool",
      "value": "True"
     }
    ]
   }
  }
 ]
}

Am I doing something wrong? Keeping everything the same but switching the part to snippet or statistics works how you'd expect in both cases. I've also tried this on a few more channels and get the same results.

Answer 1

I think this is working as intended. See YouTube API - No channel branding settings returned for queries by username. Tl;dr: even though you can look for channels by using their usernames, the migration from V2 carried with it the fact that not every YouTube channel has a unique username, so that's why it works correctly when you use the channel ID (which is unique). I also tried it by specifying forMine instead of the channel ID and it worked as expected.