base64编码长度参数

问题描述

我正在解码base64字符串，对其进行修改，然后使用Ruby重新对其进行编码.我重新编码时的问题是，ruby编码库在60个左右的字符后添加了换行符.如何告诉我每行没有最大字符数?

I am decoding a base64 string, modifying it, and re-encoding it with Ruby. The problem when I re-encode it is that the ruby encode library is adding a linebreak after 60 or so characters. How can I tell it to not have max characters per line limit?

val = "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"

decoded_val = Base64.decode64(val)
encoded_val = Base64.encode64(val)

#=> QmFzZTY0IGlzIGEgZ2VuZXJpYyB0ZXJtIGZvciBhIG51bWJlciBvZiBzaW1p
#   bGFyIGVuY29kaW5nIHNjaGVtZXMgdGhhdCBlbmNvZGUgYmluYXJ5IGRhdGEg
#   YnkgdHJlYXRpbmcgaXQgbnVtZXJpY2FsbHkgYW5kIHRyYW5zbGF0aW5nIGl0
#   IGludG8gYSBiYXNlIDY0IHJlcHJlc2VudGF0aW9uLiBUaGUgQmFzZTY0IHRl
#   cm0gb3JpZ2luYXRlcyBmcm9tIGEgc3BlY2lmaWMgTUlNRSBjb250ZW50IHRy
#   YW5zZmVyIGVuY29kaW5nLg0KDQpCYXNlNjQgZW5jb2Rpbmcgc2NoZW1lcyBh
#   cmUgY29tbW9ubHkgdXNlZCB3aGVuIHRoZXJlIGlzIGEgbmVlZCB0byBlbmNv
#   ZGUgYmluYXJ5IGRhdGEgdGhhdCBuZWVkcyBiZSBzdG9yZWQgYW5kIHRyYW5z
#   ZmVycmVkIG92ZXIgbWVkaWEgdGhhdCBhcmUgZGVzaWduZWQgdG8gZGVhbCB3
#   aXRoIHRleHR1YWwgZGF0YS4gVGhpcyBpcyB0byBlbnN1cmUgdGhhdCB0aGUg
#   ZGF0YSByZW1haW5zIGludGFjdCB3aXRob3V0IG1vZGlmaWNhdGlvbiBkdXJp
#   bmcgdHJhbnNwb3J0LiBCYXNlNjQgaXMgdXNlZCBjb21tb25seSBpbiBhIG51
#   bWJlciBvZiBhcHBsaWNhdGlvbnMgaW5jbHVkaW5nIGVtYWlsIHZpYSBNSU1F
#   LCBhbmQgc3RvcmluZyBjb21wbGV4IGRhdGEgaW4gWE1MLg==

推荐答案

RFC 4648:Base16，Base32和Base64数据编码的意思是:

因此换行符很好，即使它们不严格符合RFC 4648，几乎所有内容都将忽略它们.

So the newlines are fine and pretty much everything will ignore them even if they're not strictly compliant with RFC 4648.

此外，精细手册这么说:

返回bin的Base64编码版本.此方法符合RFC2045.每60个编码的字符都会添加换行符[sic].

Returns the Base64-encoded version of bin. This method complies with RFC 2045. Line feeds are added to every 60 encoded charactors [sic].

所以60个字符的行长度是有意的并且是指定的.如果您想要严格的RFC 4648 Base64(即没有换行符)，则有:

So the 60 character line length is intentional and specified. If you want strict RFC 4648 Base64 (i.e. no newlines), then there is strict_encode64:

返回bin的Base64编码版本.此方法符合RFC4648.不添加换行符.

Returns the Base64-encoded version of bin. This method complies with RFC 4648. No line feeds are added.

所以您可以说Base64.strict_encode64(val)来获取所需的输出.

So you can say Base64.strict_encode64(val) to get the output you're looking for.

作为参考，这是RFC 2045的相关部分:

And for reference, here's the relevant section of RFC 2045:

所以60个字符的行长多少有些随意，但自60 < 76起符合RFC 2045.

So the 60 character line length is somewhat arbitrary but compliant with RFC 2045 since 60 < 76.

这篇关于base64编码长度参数的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持！