Rails：如何处理“属性应该是数组，但是是字符串”。错误？ [英] Rails: How to handle "Attribute was supposed to be a Array, but was a String" error?

问题描述

我有一张表，其中一栏是文本类型。
其中有一个小字符串，应将其序列化为数组

I have a table with one column that is of text type. There's a small string in it that should be serialized as an array

serialize :image_urls, Array 

有时候，SQL插入数据的速度更快。
在这种情况下，我以字符串形式进行插入

There are times when SQL is just faster for inserting data. When this is the case, I do the insert as a string

["image1.jpg", "image2.jpg"]

由于我在插入字符串时，Rails应用程序在尝试读取字符串时会崩溃数据，并显示以下错误消息：

Since I'm inserting a string my Rails app crashes when it tries to read the data, with the following error message:

Attribute was supposed to be a Array, but was a String

有没有办法避免抛出此错误，或者捕获并转换数据？

我的意思是将字符串转换为数组只是一个简单的调用，因此，这应该很容易。我只是不知道在哪里或如何实现。

---

我认为可以覆盖object_from_yaml，但是我不确定在哪里进行这项工作。

我在正确的轨道上吗？

I mean converting the string to an array is just a simple call, so, this should be easy. I just don't know where, or how to accomplish it.

---

I sort of think overriding object_from_yaml, but I'm not sure where to do this work.
Am I in the right track?

推荐答案

来自精读手册：

serialize （attr_name，class_name = Object）

[...]序列化是通过YAML完成的。

serialize(attr_name, class_name = Object)
[...] The serialization is done through YAML.

因此，该列应包含 image_urls 但'[ image1 .jpg， image2.jpg]'不是YAML数组。如果您想处理原始序列化数据，则应该使用类似

So the column should contain a YAMLized version of your image_urls but '["image1.jpg", "image2.jpg"]' is not a YAML array. If you want to muck around with the raw serialized data then you should use something like

["image1.jpg", "image2.jpg"].to_yaml
# ---------------------------^^^^^^^

生成字符串。

或者更好的是，停止使用 serialize 完全支持一个单独的表。

Or better, stop using serialize altogether in favor of a separate table.

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