[Archivesspace_Users_Group] partially update a record through API

[Mang Sun]

I am trying to partially update accession records by setting PUBLISH to 
false using REST API, but I can't get it done successfully.
For example, run the following command to update one accession record,
curl_as username password -d "@accession.json" -v "the AS API 
url/repositaries/2/accession/1"

accession.json contains
{
"publish" : false
}

but I get the following complaints

{"error":{"id_0":["Property is required but was 
missing"],"accession_date":["Property is required but was 
missing"]},"warning":null,"invalid_object":"#<JSONModel(:accession) 
{\"publish\"=>true, \"jsonmodel_type\"=>\"accession\", 
\"external_ids\"=>[], \"related_accessions\"=>[], \"subjects\"=>[], 
\"linked_events\"=>[], \"extents\"=>[], \"dates\"=>[], 
\"external_documents\"=>[], \"rights_statements\"=>[], 
\"deaccessions\"=>[], \"related_resources\"=>[], 
\"restrictions_apply\"=>false, \"access_restrictions\"=>false, 
\"use_restrictions\"=>false, \"linked_agents\"=>[], \"instances\"=>[]}>"}


Any idea?

Mang Sun
Rice U.