nsq使用的TOML配置文件规范文档中文版

在阅读 nsq 源码的时候，发现nsq使用 TOML 配置文件规范。顺带翻译了大部分。采用英中文混排的方式，这样比较容易理解。

toml-lang/toml

TOML

Tom's Obvious, Minimal Language.     直观的，最小化的语言

By Tom Preston-Werner.

Latest tagged version:  v0.2.0.

Be warned, this spec is still changing a lot. Until it's marked as 1.0, you should assume that it is unstable and act accordingly.

Objectives

TOML aims to be a minimal configuration file format that's easy to read due to obvious semantics. TOML is designed to map unambiguously to a hash table. TOML should be easy to parse into data structures in a wide variety of languages.

最小化配置文件格式，直观的语意，很容易阅读。没有歧义的映射成哈希表。可以简单的解析成各类语言的数据结构。

Example

# This is a TOML document. Boom.

title  = "TOML Example"

[owner]
name  = "Tom Preston-Werner"
organization  = "GitHub"
bio  = "GitHub Cofounder & CEO\nLikes tater tots and beer."
dob  = 1979-05-27T07:32:00Z  # First class dates? Why not?

[database]
server  = "192.168.1.1"
ports  = [ 8001, 8001, 8002 ]
connection_max  = 5000
enabled  =  true

[servers]

   # You can indent as you please. Tabs or spaces. TOML don't care.
  [servers.alpha]
  ip  = "10.0.0.1"
  dc  = "eqdc10"

  [servers.beta]
  ip  = "10.0.0.2"
  dc  = "eqdc10"

[clients]
data  = [ ["gamma", "delta"], [1, 2] ]

# Line breaks are OK when inside arrays
hosts  = [
  "alpha",
  "omega"
]

Spec

• TOML is case sensitive.
• Whitespace means tab (0x09) or space (0x20).

规范

     TOML 是大小写敏感的

     空白符 指的是(0x09) tab 和 空格(0x20)

Comment

Speak your mind with the hash symbol. They go from the symbol to the end of the line.

# I am a comment. Hear me roar. Roar.
key  = "value"  # Yeah, you can do this.

注释

使用 # 代表你的想法。从 # 开始，到行的结尾

String

There are four ways to express strings: basic, multi-line basic, literal, and multi-line literal. All strings must contain only valid UTF-8 characters.

字符串

有四中方式表达字符串：基础，多行基础，字面，多行字面。全部的只能包含 UTF-8 字符

Basic strings are surrounded by quotation marks. Any Unicode character may be used except those that must be escaped: quotation mark, backslash, and the control characters (U+0000 to U+001F).

"I'm a string. \"You can quote me\". Name\tJos\u00E9\nLocation\tSF.”

基础字符串  双引号包裹。Unicode 字符均可以使用。部分字符须要转义，包括，引号，反斜杠，控制字符 (U+0000 to U+001F)

For convenience, some popular characters have a compact escape sequence.

\b        - backspace      (U+0008)
\t        - tab            (U+0009)
\n        - linefeed        (U+000A)
\f        - form feed      (U+000C)
\r        - carriage return (U+000D)
\"        - quote          (U+0022)
\/        - slash          (U+002F)
\\        - backslash      (U+005C)
\uXXXX    - unicode        (U+XXXX)
\UXXXXXXXX - unicode        (U+XXXXXXXX)

Any Unicode character may be escaped with the \uXXXX or \UXXXXXXXX forms. Note that the escape codes must be valid Unicode code points.

Unicode 字符能够转义，使用 \uXXXX 或者 \UXXXX 的形式。编码必须是有效的 unicode 编码点。好比“中文”的 unicode 编码：\u4e2d\u6587

Other special characters are reserved and, if used, TOML should produce an error.

其余特殊字符不容许，TOML 会出错。

ProTip™: You may notice that the above string specification is the same as JSON's string definition, except that TOML requires UTF-8 encoding. This is on purpose.

ProTip：上面的字符串定义和json字符串一致。除了 TOML 须要 utf-8 编码，相似于 java 中的 native2ascii 方法，而 json 字符串直接能够写中文。这是有意为之的。

Sometimes you need to express passages of text (e.g. translation files) or would like to break up a very long string into multiple lines. TOML makes this easy.  Multi-line basic strings are surrounded by three quotation marks on each side and allow newlines. If the first character after the opening delimiter is a newline (0x0A), then it is trimmed. All other whitespace remains intact.

多行基础字符串 表示文本段，或者想分裂长的字符串到多行。3个双引号包裹，容许新行。开始标识符后面的换行符会被删除（显而易见）。其它空白符不会受到影响。

# The following strings are byte-for-byte equivalent: key3 更直观
key1  = "One\nTwo"
key2  = """One\nTwo"""
key3  = """
One
Two"""

For writing long strings without introducing extraneous whitespace, end a line with a \. The \ will be trimmed along with all whitespace (including newlines) up to the next non-whitespace character or closing delimiter. If the first two characters after the opening delimiter are a backslash and a newline (0x5C0A), then they will both be trimmed along with all whitespace (including newlines) up to the next non-whitespace character or closing delimiter. All of the escape sequences that are valid for basic strings are also valid for multi-line basic strings.

为了写长字符串而不引入无关空白符，使用 \ 结束一行。

\ 字符，一直到下一个非空白字符或者结束标识符之间的全部空白字符包括换行符，都会被删除掉。

开始标识符若是后面是 \ 字符，直到下一个非空白字符之间的全部字符，包括换行符都会被删除掉。

基础字符串中的转义字符对多行基础字符串仍然有效。

# The following strings are byte-for-byte equivalent:    这是个好例子
key1  = "The quick brown fox jumps over the lazy dog."

key2  = """
The quick brown \


  fox jumps over \
    the lazy dog."""

key3  = """\
      The quick brown \
      fox jumps over \
      the lazy dog.\
      """

Any Unicode character may be used except those that must be escaped: backslash and the control characters (U+0000 to U+001F). Quotation marks need not be escaped unless their presence would create a premature closing delimiter.

unicode 字符的规则和基础字符串一致。双引号不须要转义，除了那些制造歧义的状况。

If you're a frequent specifier of Windows paths or regular expressions, then having to escape backslashes quickly becomes tedious and error prone. To help, TOML supports literal strings where there is no escaping allowed at all.  Literal strings are surrounded by single quotes. Like basic strings, they must appear on a single line:

若是频繁指定windows路径或正则表达式，转义反斜杠很快变得枯燥且容易出错。 TOML 支持 字面字符串，不容许转义，单引号包裹，单行。

# What you see is what you get.
winpath   = 'C:\Users\nodejs\templates'
winpath2  = '\\ServerX\admin$\system32\'
quoted   = 'Tom "Dubs" Preston-Werner'
regex     = '<\i\c*\s*>'

Since there is no escaping, there is no way to write a single quote inside a literal string enclosed by single quotes. Luckily, TOML supports a multi-line version of literal strings that solves this problem.  Multi-line literal strings are surrounded by three single quotes on each side and allow newlines. Like literal strings, there is no escaping whatsoever. If the first character after the opening delimiter is a newline (0x0A), then it is trimmed. All other content between the delimiters is interpreted as-is without modification.

由于没有转义，因此单引号包裹的字面字符串不能包含单引号。很是幸运，TOML 支持多行字面字符串。3个单引号包裹，支持换行，一样不能转义。起始标识符后面跟随的换行会被删除。其它内容原封不动的保留。

regex2  = '''I [dw]on't need \d{2} apples'''
lines   = '''
The first newline is
trimmed in raw strings.
  All other whitespace
  is preserved.
'''

For binary data it is recommended that you use Base64 or another suitable ASCII or UTF-8 encoding. The handling of that encoding will be application specific.

Integer

Integers are bare numbers, all alone. Feeling negative? Do what's natural. 64-bit minimum size expected.

Float

Floats are numbers with a single dot within. There must be at least one number on each side of the decimal point. 64-bit (double) precision expected.

Boolean

Booleans are just the tokens you're used to. Always lowercase.

Datetime

Datetimes are ISO 8601 dates, but only the full zulu form is allowed.

Array

Arrays are square brackets with other primitives inside. Whitespace is ignored. Elements are separated by commas. Data types may not be mixed.

中括号包裹基本类型，忽略空白符，元素逗号分隔，数据类型不能混合，必须单一。

[ 1, 2, 3 ]
[ "red", "yellow", "green" ]
[ [ 1, 2 ], [3, 4, 5] ]
[ [ 1, 2 ], ["a", "b", "c"] ]  # this is ok
[ 1, 2.0 ]  # note: this is NOT ok

Arrays can also be multiline. So in addition to ignoring whitespace, arrays also ignore newlines between the brackets. Terminating commas are ok before the closing bracket.

支持多行。忽略空白符，一样还忽略中括号内的换行符，闭括号前的逗号也会忽略。

key  = [
  1, 2, 3
]

key  = [
  1,
  2,  # this is ok
]

Table

Tables (also known as hash tables or dictionaries) are collections of key/value pairs. They appear in square brackets on a line by themselves. You can tell them apart from arrays because arrays are only ever values.

字典

key/value对 的集合。做为单独一行，出如今方括号中。和数组的不一样就是，数组是做为值存在。

Under that, and until the next table or EOF are the key/values of that table. Keys are on the left of the equals sign and values are on the right. Keys start with the first character that isn't whitespace or [ and end with the last non-whitespace character before the equals sign. Keys cannot contain a # character. Key/value pairs within tables are not guaranteed to be in any specific order.

在这之下，直到下一个表，或者 EOF，都是字典的 key/value 对。等号的左边是 key，右边是值。key 从第一个非空白字符或 [ 开始，到等号左边的最后一个非空白字符结束。key 不能包含 # 符号。表中的 key/value 对不保证某种顺序。

You can indent keys and their values as much as you like. Tabs or spaces. Knock yourself out. Why, you ask? Because you can have nested tables. Snap.

key 和 value 可使用空白符缩进。随便！为何要这么作，由于 字典支持缩进。

Nested tables are denoted by table names with dots in them. Name your tables whatever crap you please, just don't use #, ., [ or ].

嵌套字典点表示法，名中有点号。字典名能够随便起，只要不包含 #, ., [, ]。

[dog.tater]
type  = "pug"

In JSON land, that would give you the following structure:

{ "dog": { "tater": { "type": "pug" } } }

You don't need to specify all the super-tables if you don't want to. TOML knows how to do it for you.

下面这个例子很 happy

# [x] you
# [x.y] don't
# [x.y.z] need these
[x.y.z.w]  # for this to work

Empty tables are allowed and simply have no key/value pairs within them.

支持空字典。

As long as a super-table hasn't been directly defined and hasn't defined a specific key, you may still write to it.

尽管父字典没有直接定义，也没有定义具体的 key，你仍然能够往里面写。

You cannot define any key or table more than once. Doing so is invalid.

key 和 table 不能重复定义！

# DO NOT DO THIS

[a]
b  = 1

[a]
c  = 2

# DO NOT DO THIS EITHER

[a]
b  = 1

[a.b]
c  = 2

All table names and keys must be non-empty.

# NOT VALID TOML
[]
[a.]
[a..b]
[.b]
[.]
= "no key name"  # not allowed

Array of Tables

The last type that has not yet been expressed is an array of tables. These can be expressed by using a table name in double brackets. Each table with the same double bracketed name will be an element in the array. The tables are inserted in the order encountered. A double bracketed table without any key/value pairs will be considered an empty table.

字典数组

双中括号包裹字典名。有相同字典名的每个字典是数组中的一个元素。（记住上面，普通字典名不能重复定义）。元素的顺序按定义插入数组中。没有 key/value 对的字典是空的。

[[products]]
name  = "Hammer"
sku  = 738594937

[[products]]

[[products]]
name  = "Nail"
sku  = 284758393
color  = "gray"

In JSON land, that would give you the following structure.

{
  "products": [
    { "name": "Hammer", "sku": 738594937 },
    { },
    { "name": "Nail", "sku": 284758393, "color": "gray" }
  ]
}

You can create nested arrays of tables as well. Just use the same double bracket syntax on sub-tables. Each double-bracketed sub-table will belong to the most recently defined table element above it.

字典数组支持嵌套。子字典数组的语法和数组字典同样。

[[fruit]]
  name  = "apple"

  [fruit.physical]
    color  = "red"
    shape  = "round"

  [[fruit.variety]]
    name  = "red delicious"

  [[fruit.variety]]
    name  = "granny smith"

[[fruit]]
  name  = "banana"

  [[fruit.variety]]
    name  = "plantain"

The above TOML maps to the following JSON.

{
  "fruit": [
    {
      "name": "apple",
      "physical": {
        "color": "red",
        "shape": "round"
      },
      "variety": [
        { "name": "red delicious" },
        { "name": "granny smith" }
      ]
    },
    {
      "name": "banana",
      "variety": [
        { "name": "plantain" }
      ]
    }
  ]
}

Attempting to define a normal table with the same name as an already established array must produce an error at parse time.

# INVALID TOML DOC
[[fruit]]
  name  = "apple"

  [[fruit.variety]]
    name  = "red delicious"

   # This table conflicts with the previous table
  [fruit.variety]
    name  = "granny smith"

Seriously?

Yep.

But why?

Because we need a decent human-readable format that unambiguously maps to a hash table and the YAML spec is like 80 pages long and gives me rage. No, JSON doesn't count. You know why.

YAML 的规范80页长，让我恼火。

Oh god, you're right

Yuuuup. Wanna help? Send a pull request. Or write a parser. BE BRAVE.

Implementations

If you have an implementation, send a pull request adding to this list. Please note the commit SHA1 or version tag that your parser supports in your Readme.