sql-crud-adapter.js

function SqlCrudAdapter (queryExecutorFunction) {
    function getObjects (tableName, filter, callback) {
      filter = filter || [];
      let where = "";
      if (filter.length > 0) {
        where += " WHERE " + filter.map(fi => "" + fi.name + fi.op + fi.value).join(" AND ");
      }
  
      const command = "SELECT * FROM " + tableName + where;
      queryExecutorFunction(command, (error, results) => {
        if (error) {
          throw error;
        }
        callback(results.rows);
      });
    }
  
    function deleteObject (tableName, idValue, callback) {
      const command = "DELETE FROM " + tableName + " WHERE id='" + idValue + "'";
      queryExecutorFunction(command, (error, results) => {
        if (error) {
          throw error;
        }
        callback(results);
      });
    }
  
    function createObject (tableName, object, callback) {
      const valueNames = [];
      const valueIndexes = [];
      const values = [];
      Object.keys(object).forEach((key, index) => {
        if (object[key] !== undefined) {
          valueNames.push(key);
          valueIndexes.push("$" + (index + 1));
          values.push(object[key]);
        }
      });
      const command = "INSERT INTO " + tableName + " (" + valueNames.join(", ") + ") VALUES (" + valueIndexes.join(", ") + ") RETURNING id";
      queryExecutorFunction(command, values, (error, results) => {
        if (error) {
          throw error;
        }
        callback(results.rows[0].id);
      });
    }
  
    function updateObject (tableName, object, callback) {
      const valueNames = [];
      const values = [];
      Object.keys(object).forEach((key, index) => {
        if (object[key] !== undefined) {
          valueNames.push(key + " = $" + (index + 1));
          values.push(object[key]);
        }
      });
      const command = "UPDATE " + tableName + " SET " + valueNames.join(", ") + " WHERE id = '" + object.id  + "'";
      queryExecutorFunction(command, values, (error) => {
        if (error) {
          throw error;
        }
        callback(object);
      });
    }
  
    return {
      create: createObject,
      retrieve: getObjects,
      update: updateObject,
      delete: deleteObject
    }
}

module.exports = SqlCrudAdapter;