code: function getTags(params, config, conn) {
  
  
    // defaults
    config = config || require('../config/config.js')
  
    params.limit = 100
  
  
    // main
    return new Promise((resolve, reject) => {
  
      if (!conn) {
        var conn = wc_db.getConnection(config.db)
      }
  
      if (params.uri) {
        var sql = 'SELECT t.tag from Media m left join MediaTag mt on m.id = mt.media_id left join Tag t on mt.tag_id = t.id  where m.uri = :uri order by t.tag LIMIT :limit '
      } else {
        var sql = 'SELECT * from Tag order by id LIMIT :limit '
      }
      debug(sql)
  
      conn.query(sql, { replacements: { "limit" : params.limit, "uri" : params.uri } }).then(function(ret){
        return resolve({"ret" : ret, "conn" : conn})
      }).catch(function(err) {
        return reject({"err" : err, "conn" : conn})
      })
  
    })
  
  }
docs: Get list of tags
  @param {Object} params  Info about tags.
  @param {Object} config  The optional config.
  @param {Object} conn    The optional db connection.
  @return {Object} Promise with success or fail.