使用Flask和Python从Mongo中提取多个记录

Question

我还在这里学习，目前正在尝试使用FLASK来创建一个Restful接口。

我想做的是从一个mongo数据库中提取一组记录。我已经成功使用了find_one()，现在在探索如何遍历一个游标。

这段代码只显示了一条记录，而我知道至少有5条。

@app.route('/oer/api/v1.0/getType/', methods = ['GET'])
def getType():

    # Prepare a dictionary object to hold the result of any processing
    result = {}

    # Get hold of DB connection
    db_connection = getDbConnection()
    db = db_connection['OER']
    # Extract all records passed for the paramater that matches "Type": ie MOOC
    oerType = request.args.get("oerType");
    # test to see that there is something in the string if so try to get a record
    # Not doing this test yet lets get it working with a known record first 

    for d in db.oer_records.find({"Type":oerType}): 
        result.update(make_public_page(d))

    return jsonify(result) 

所以它能工作，但只返回了一条json文档，而不是一组记录？我以为result.update会在每次循环时添加一条新记录。顺便说一下，make_public_page()会去掉BISON ID，以便jsonify能够正常工作。

这是它返回的内容：

{
    "Account No": 1,
    "Country/ continent": "Argentina",
    "Educational Level": "Schools",
    "Educational Level (ISCED)": "2|3",
    "End year": "",
    "Funders": "",
    "Geolocation": "",
    "Initiative HQ address": "",
    "Initiative HQ city": "",
    "Initiative URL": "http://www.gleducar.org.ar",
    "Type": "OER"
}

任何帮助都非常感谢。

谢谢

Answer 1

当你使用 dict.update(dict2) 时，你是在把字典 dict2 的键值对添加到 dict 中，这样就变成了一个大的字典。如果你想要的其实是创建一个字典的列表，那就需要用不同的方法。

mylist = []
mylist.append(dict)

这段话可以用你的代码来表示：

@app.route('/oer/api/v1.0/getType/', methods = ['GET'])
def getType():

    # Prepare a dictionary object to hold the result of any processing
    result = []  # create a list instead of dict

    # Get hold of DB connection
    db_connection = getDbConnection()
    db = db_connection['OER']
    # Extract all records passed for the paramater that matches "Type": ie MOOC
    oerType = request.args.get("oerType");
    # test to see that there is something in the string if so try to get a record
    # Not doing this test yet lets get it working with a known record first 

    for d in db.oer_records.find({"Type":oerType}): 
        result.append(make_public_page(d))  # append to the list of dicts

    return jsonify(items=result)