Can I use $expand to get Managed Metadata column values?

Question

I want to get a list, using REST, which include Managed Metadata columns. Currently I get a TermGuid for these columns, which I then have to do more work on to get their actual default values.

Is there a way to do this all in one call? Something like:

/sites/mysite/_api/web/lists/getbytitle('My List')/items?$expand=managed_metadata

Answer 1

SP.Taxonomy.TaxonomyFieldValue type exposes the following properties via SharePoint REST API:

• Label
• TermGuid
• WssId

How to retrieve Taxonomy field values using SharePoint REST in JavaScript

Assume Pages library contains:

• Category single valued taxonomy field
• Categories mutli-valued taxonomy field

Then the following example demonstrates how to perform GET request to retrieve taxonomy field values:

function getJson(url,success,failure)
{
    $.ajax({
      type: "GET", 
      headers: { 
            "accept": "application/json;odata=verbose",
            "content-type": "application/json;odata=verbose"
      }, 
      url: url, 
      success: success,
      failure: failure 
   });
}

function getListItems(listTitle,success,failure)
{
    var endpointUrl = _spPageContextInfo.webAbsoluteUrl + "/_api/web/lists/GetByTitle('" + listTitle + "')/items";
    getJson(endpointUrl,
      function(data){
        success(data.d.results);    
      },
      failure);
}


//Usage
getListItems('Pages',
  function(items){
      //print info
      for(var i = 0; i < items.length; i++) {
          console.log(items[i].Category.Label);  //single-valued taxonomy field  
          if(items[i].Categories.results.length > 0) 
             console.log(items[i].Categories.results[0].Label);  //print first value of multiple taxonomy field
      }
  },
  function(error){
     console.log(JSON.stringify(error)); 
  }
);

But unfortunately there is a known bug with retrieving a Label from single-valued taxonomy field using SharePoint REST GET request.

The workaround is to perform POST request to retrieve taxonomy field values as demonstrated below:

function postJson(endpointUrl,payload,success,failure)
{
    $.ajax({
      type: "POST", 
      headers: { 
            "accept": "application/json;odata=verbose",
            "content-type": "application/json;odata=verbose",
            "X-RequestDigest": $("#__REQUESTDIGEST").val()
      }, 
      data: JSON.stringify(payload),
      url: endpointUrl, 
      success: success,
      failure: failure 
   });
}


function getListItems(listTitle, queryViewXml,success,failure)
{
   var queryPayload = { 
       'query':{ 
           '__metadata': { 'type': 'SP.CamlQuery' },
           'ViewXml': queryViewXml
        } 
   }; 
   var endpointUrl = _spPageContextInfo.webAbsoluteUrl + "/_api/web/lists/getbytitle('" + listTitle + "')/getitems";
   postJson(endpointUrl,queryPayload,
     function(data){
        success(data.d.results);    
     },failure);
}

//Usage
getListItems('Pages','<View><Query/></View>',
  function(items){
      //print info  
      for(var i = 0; i < items.length; i++) {
          console.log(items[i].Category.Label);  //single-valued taxonomy field  
          if(items[i].Categories.results.length > 0)  
             console.log(items[i].Categories.results[0].Label);  //print first value of multiple taxonomy field
      }
  },
  function(error){
     console.log(JSON.stringify(error)); 
  });  

Answer 2

You can do a workaround using the TaxCatchAll field as long as you know which terms belong to which taxonomy field - if you have multiple.

/_api/web/Lists/GetByTitle('<list>')/Items/?$select=*,TaxCatchAll/Term&$filter=TaxCatchAll/Term eq 'Puzzlepart'&$expand=TaxCatchAll