Ruby-on-rails 什么是 JSON 八位字节，为什么需要两个？
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What is a JSON octet and why are two required?
提问by MorningHacker
I have incoming data, which I store in a variable messages:
我有传入的数据，我将其存储在一个变量中messages：
connection = ContextIO::Connection.new(key, secret)
messages = connection.all_messages(:account => account, :limit => 100, :since => (Time.now - 3000.day ))
The variable messagesis formatted in JSON. Then I execute this:
该变量messages采用 JSON 格式。然后我执行这个：
foo = JSON.parse(messages)['data']
Most of the time this works. Every now and again, I get this error message:
大多数时候这是有效的。时不时地，我收到此错误消息：
A JSON text must at least contain two octets!
That error message then refers to the line JSON.parse(messages)['data']
该错误消息然后指的是该行 JSON.parse(messages)['data']
What is an octet?
Why must JSON text contain at least two octets?
How do I prevent my code from breaking every time
messagesdoes not have two octets?
什么是八位字节？
为什么 JSON 文本必须至少包含两个八位字节？
每次
messages没有两个八位字节时，如何防止我的代码被破坏？
Thanks!
谢谢！
回答by phihag
- An octet is a group of 8 bits. Today, octet is synonymous with byte, but byte historically referred to any "native" grouping of bits, and that could mean 4,6,7, or 8 bits.
- JSON text must contain at least two octets because the top-level structure of a JSON document is an array or object, and the shortest representations of those are
[]and{}, respectively. - Check the value
messages. It is probably empty, unset or consists of a single digit (like4), which is notvalid JSON, but accepted by many JSON implementations.
- 八位字节是一组 8 位。今天，八位字节是字节的同义词，但字节在历史上指的是任何“本机”位分组，这可能意味着 4、6、7 或 8 位。
- JSON 文本必须至少包含两个八位字节，因为 JSON 文档的顶级结构是数组或对象，它们的最短表示分别是
[]和{}。 - 检查值
messages。它可能为空、未设置或由单个数字（如4）组成，这不是有效的 JSON，但被许多 JSON 实现接受。
回答by Stephen Moore
While I totally agree with the other answer, in my case I had a valid JSONstring but was still receiving the "JSON text must contain at least two octets" error message when trying to JSON.parse.
虽然我完全同意另一个答案，但在我的情况下，我有一个有效的JSON字符串，但在尝试JSON.parse.
My issue was that I was not specifying content type of application/json. Once I added that, JSON.parseworked without error.
我的问题是我没有指定application/json. 一旦我添加了它，就可以正常JSON.parse工作。
Hope this helps someone else.
希望这对其他人有帮助。
