Rest API expand folder then get column

Question

I have a rest api right now that accesses files in a folder. It works and returns the name of the file and a count accurately. I am trying to get data from a column field as well but everything I've done returns as undefined. I have my code cycling through files in the folder and all I need is to get the FileType field for each item.

"/_api/web/GetFolderByServerRelativeUrl('" + folderUrl + "')?$expand=Folders,Files&$select=fileType",

Answer 1

So, you are trying to do two things at once:

• Get the Item Count for the given folder
• Get the 'fileType' column for all items in the folder

This seems like a job better suited to multiple sequential REST calls, but this worked for me:

<server>/_api/web/GetFolderByServerRelativeUrl('/Pages')?$expand=Folders,Files/ListItemAllFields/FieldValuesAsText&$select=ItemCount,Folders/ItemCount,Folders/Name,Files/ListItemAllFields/FieldValuesAsText/File_x005f_x0020_x005f_Type,Files/ListItemAllFields/FieldValuesAsText/fileLeafRef

Here I'm doing multiple levels of expansion and selection:

$expand=Folders,Files/ListItemAllFields/FieldValuesAsText

• The additional expansion on Files was just to get to the File_x005f_x0020_x005f_Type value for each file, which is the same as the file extension

$select=ItemCount,Folders/ItemCount,Folders/Name,Files/ListItemAllFields/FieldValuesAsText/File_x005f_x0020_x005f_Type,Files/ListItemAllFields/FieldValuesAsText/fileLeafRef

• This selects ItemCount for the current folder (the folder you specified in GetFolderByServerRelativeUrl), ItemCount and Name for each sub-folder, and File_x005f_x0020_x005f_Type and fileLeafRef (the literal file name) for all files contained in the current folder, regardless of sub-folders.

Since this query goes several levels deep, it returns a lot of metadata that you probably don't need. So I would recommend using the odata=nometadata headers when making your REST call:

Accept:application/json;odata=nometadata Content-Type:application/json;odata=nometadata

Edit: If I recall correctly, the nometadata property only works with SP 2016+