翻译---express 4.x版本官网的app.set()的属性和使用方法

2019-11-08 02:39:53

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app.set(name, value)

Assigns setting name to value, where name is one of the PRoperties from theapp settings table.

分配设定名字给值，这里的名字是一个 app 设定表的属性

Calling app.set('foo', true) for a Boolean property is the same as callingapp.enable('foo'). Similarly, calling app.set('foo', false) for a Boolean property

把 app.set('foo', true) 作为一个布尔类型属性是和 app.enable('foo')一样的。相似地，把app.set('foo', false)作为一个布尔类型属性

is the same as calling app.disable('foo').

是和 app.disable('foo')一样的。

Retrieve the value of a setting with app.get().

检索设置的值用 app.get().

app.set('title', 'My Site');app.get('title'); // "My Site"

application Settings

应用设定

If name is one of the application settings, it affects the behavior of the application. The following table lists application settings.

如果名字是一个应用程序设置，它会影响应用程序的行为方式。下表列出应用程序设置

Property Type Value Default

Property	Type	Value	Default
`case sensitive routing` `区分大小写` `路由选择`	Boolean	Enable case sensitivity. 启用区分大小写	Disabled. Treats "/Foo" and "/foo" as the same. 不启用。把"/Foo" and "/foo" 看作是一样的
`env` `外部命令`	String	Environment mode. 列出所有环境变量及其赋值	`process.env.NODE_ENV` (`NODE_ENV` environment variable) or “development”.
`etag` `被请求变量的实体值，实体标签`	Varied	Set the ETag response header. For possible values, see the `etag` options table. 设置 ETag 请求的报头。对于可能的值，看 `etag` options table More about the HTTP ETag header.
`jsonp callback name` `jsonp 回调名字`	String	Specifies the default JSONP callback name. 指定默认 jsonp 回调名字（开启透明的 jsonp支持）	`?callback=`
`json replacer` `json 替代者`	String	JSON replacer callback. JSON 替代者回调	`null` `空`
`json spaces` `json 空间`	Number	When set, sends prettified JSON string indented with the specified amount of spaces. 当设置好的时候, 发送修饰好了的和打算的指定大小的空间 json 字符串	Disabled. 不启用
`query parser` `查询解析器`	String	The query parser to use, either “simple” or “extended”. The simple query parser is based on Node’s 查询解析器使用，要么简单要么拓展。这个简单的查询解析器是基于 node 的本地查询解析器， native query parser, querystring. The extended query parser is based on qs. querystring. 这个拓展的查询解析器是基于 qs.querystring.	"extended"
`strict routing` `严格的路由选择` `（严格路径）`	Boolean	Enable strict routing. 启用严格的路由选择（启用后不会忽略路径末尾的 '/'）	Disabled. Treats "/foo" and "/foo/" as the 不启用。把"/Foo" and "/foo" 看作是一样的 same by the router.
`subdomain` `offset` `子域名偏移量`	Number	The number of dot-separated parts of the host to remove to access subdomain. 许多用点号分隔的主机部分被移除为了访问子域	2
`trust proxy` `信任代理`	Varied	Indicates the app is behind a front-facing proxy, and to use the `X-Forwarded-` headers to determine the connection and the ip address of the client. NOTE: `X-Forwarded-` headers are easily spoofed and the detected IP addresses are unreliable. `trust proxy` is disabled by default. When enabled, Express attempts to determine the IP address of the client connected through the front-facing proxy, or series of proxies. The `req.ips` property, then, contains an array of IP addresses the client is connected through. To enable it, use the values described in the `trust proxy` options table. The `trust proxy` setting is implemented using the proxy-addr package. For more information, see its documentation. 指示应用程序是一个前置代理的背后，并用x-forwarded 头来确定连接和客户端的IP地址。注：x-forwarded 头很容易伪造并且检测到的IP地址是不可靠的。 zhǐ指 shì示 yìng应 yòng用 chéng程 xù序 shì是 yī一 gè个 qián前 zhì置 dài代 lǐ理 de的 bèi背 hòu后， bìng并 yòng用 x - f o r w a r d e d * tóu头 lái来 què确 dìng定 lián连 jiē接 hé和 kè客 hù户 duān端 de的 I P dì地 zhǐ址。 zhù注： x - f o r w a r d e d * tóu头 hěn很 róng容 yì易 wěi伪 zào造 hé和 jiǎn检 cè测 dào到 de的 I P dì地 zhǐ址 shì是 bù不 kě可 kào靠 de的。 trust proxy is disabled by default. When enabled, Express attempts to determine the IP address of the client connected through the front-facing proxy, or series of proxies. The req.ips property, then, contains an array of IP addresses the client is connected through. To enable it, use the values described in the trust proxy options table. 默认情况下信任代理已禁用。启用时，表示试图通过前面的代理或一系列代理连接来确定客户端的IP地址的req.ips财产，然后，包含IP地址的客户端连接到阵列。要启用它，请使用“信任代理选项表”中描述的值。 mò默 rèn认 qíng情 kuàng况 xià下 xìn信 rèn任 dài代 lǐ理 yǐ已 jìn禁 yòng用。 qǐ启 yòng用 shí时， biǎo表 shì示 shì试 tú图 tōng通 guò过 qián前 miàn面 dī的 dài代 lǐ理 huò或 yī一 xì系 liè列 dài代 lǐ理 lián连 jiē接 lái来 què确 dìng定 kè客 hù户 duān端 de的 I P dì地 zhǐ址。 de的 r e q . i p s cái财 chǎn产， rán然 hòu后， bāo包 hán含 I P dì地 zhǐ址 de的 kè客 hù户 duān端 lián连 jiē接 dào到 zhèn阵 liè列。 yào要 qǐ启 yòng用 tā它， qǐng请 shǐ使 yòng用 “ xìn信 rèn任 dài代 lǐ理 xuǎn选 xiàng项 biǎo表 ” zhōng中 miáo描 shù述 de的 zhí值。 The trust proxy setting is implemented using the proxy-addr package. For more information, see its documentation. 信托代理设置使用代理地址封装实现。有关更多信息，请参见其文档。	Disabled.
`views` `视图`	String or Array	A directory or an array of directories for the application's views. 应用程序视图的一个目录或者一组目录（用于存放模板文件） If an array, the views are looked up in the order they occur in the array. 如果是一个数组，这个视图是按出现在数组里的顺序查询的	`process.cwd() + '/views'`
`view cache` `视图缓存`	Boolean	Enables view template compilation caching. 启用视图模板编译缓存	`true` in production. 在生产中true
`view engine` `视图模板引擎`	String	The default engine extension to use when omitted. 当省略了的时候默认的拓展引擎会被使用
`x-powered-by` `x驱动`	Boolean	Enables the "X-Powered-By: Express" HTTP header. 启用"X-Powered-By，Express" HTTP 报头	`true`

case sensitive routing

区分大小写

路由选择

Boolean

Enable case sensitivity.

启用区分大小写

Disabled. Treats "/Foo" and "/foo" as the same.

不启用。把"/Foo" and "/foo" 看作是一样的

env

外部命令

String

Environment mode.

列出所有环境变量及其赋值

process.env.NODE_ENV (NODE_ENV environment variable) or “development”.

etag

被请求变量的实体值，实体标签

Varied

Set the ETag response header. For possible values, see the etag options table.

设置 ETag 请求的报头。对于可能的值，看 etag options table

More about the HTTP ETag header.

jsonp callback name

jsonp 回调名字

String

Specifies the default JSONP callback name.

指定默认 jsonp 回调名字（开启透明的 jsonp支持）

?callback=

json replacer

json 替代者

String

JSON replacer callback.

JSON 替代者回调

null

空

json spaces

json 空间

Number

When set, sends prettified JSON string indented with the specified amount of spaces.

当设置好的时候, 发送修饰好了的和打算的指定大小的空间 json 字符串

Disabled.

不启用

query parser

查询解析器

String

The query parser to use, either “simple” or “extended”. The simple query parser is based on Node’s

查询解析器使用，要么简单要么拓展。这个简单的查询解析器是基于 node 的本地查询解析器，

native query parser, querystring. The extended query parser is based on qs.

querystring. 这个拓展的查询解析器是基于 qs.querystring.

"extended"

strict routing

严格的路由选择

（严格路径）

Boolean

Enable strict routing.

启用严格的路由选择（启用后不会忽略路径末尾的 '/'）

Disabled. Treats "/foo" and "/foo/" as the

不启用。把"/Foo" and "/foo" 看作是一样的

same by the router.

subdomain

offset

子域名偏移量

Number

The number of dot-separated parts of the host to remove to access subdomain.

许多用点号分隔的主机部分被移除为了访问子域

trust proxy

信任代理

Varied

Indicates the app is behind a front-facing proxy, and to use the X-Forwarded-* headers to determine the connection and the ip address of the client. NOTE: X-Forwarded-* headers are easily spoofed and the detected IP addresses are unreliable.

trust proxy is disabled by default. When enabled, Express attempts to determine the IP address of the client connected through the front-facing proxy, or series of proxies. The req.ips property, then, contains an array of IP addresses the client is connected through. To enable it, use the values described in the trust proxy options table.

The trust proxy setting is implemented using the proxy-addr package. For more information, see its documentation.

指示应用程序是一个前置代理的背后，并用x-forwarded *头来确定连接和客户端的IP地址。注：x-forwarded *头很容易伪造并且检测到的IP地址是不可靠的。

zhǐ指 shì示 yìng应 yòng用 chéng程 xù序 shì是 yī一 gè个 qián前 zhì置 dài代 lǐ理 de的 bèi背 hòu后， bìng并 yòng用 x - f o r w a r d e d * tóu头 lái来 què确 dìng定 lián连 jiē接 hé和 kè客 hù户 duān端 de的 I P dì地 zhǐ址。 zhù注： x - f o r w a r d e d * tóu头 hěn很 róng容 yì易 wěi伪 zào造 hé和 jiǎn检 cè测 dào到 de的 I P dì地 zhǐ址 shì是 bù不 kě可 kào靠 de的。

trust proxy is disabled by default. When enabled, Express attempts to determine the IP address of the client connected through the front-facing proxy, or series of proxies. The req.ips property, then, contains an array of IP addresses the client is connected through. To enable it, use the values described in the trust proxy options table.

默认情况下信任代理已禁用。启用时，表示试图通过前面的代理或一系列代理连接来确定客户端的IP地址的req.ips财产，然后，包含IP地址的客户端连接到阵列。要启用它，请使用“信任代理选项表”中描述的值。

mò默 rèn认 qíng情 kuàng况 xià下 xìn信 rèn任 dài代 lǐ理 yǐ已 jìn禁 yòng用。 qǐ启 yòng用 shí时， biǎo表 shì示 shì试 tú图 tōng通 guò过 qián前 miàn面 dī的 dài代 lǐ理 huò或 yī一 xì系 liè列 dài代 lǐ理 lián连 jiē接 lái来 què确 dìng定 kè客 hù户 duān端 de的 I P dì地 zhǐ址。 de的 r e q . i p s cái财 chǎn产， rán然 hòu后， bāo包 hán含 I P dì地 zhǐ址 de的 kè客 hù户 duān端 lián连 jiē接 dào到 zhèn阵 liè列。 yào要 qǐ启 yòng用 tā它， qǐng请 shǐ使 yòng用 “ xìn信 rèn任 dài代 lǐ理 xuǎn选 xiàng项 biǎo表 ” zhōng中 miáo描 shù述 de的 zhí值。

The trust proxy setting is implemented using the proxy-addr package. For more information, see its documentation.

信托代理设置使用代理地址封装实现。有关更多信息，请参见其文档。

Disabled.

views

视图

String or Array

A directory or an array of directories for the application's views.

应用程序视图的一个目录或者一组目录（用于存放模板文件）

If an array, the views are looked up in the order they occur in the array.

如果是一个数组，这个视图是按出现在数组里的顺序查询的

process.cwd() + '/views'

view cache

视图缓存

Boolean

Enables view template compilation caching.

启用视图模板编译缓存

true in production.

在生产中true

view engine

视图模板引擎

String

The default engine extension to use when omitted.

当省略了的时候默认的拓展引擎会被使用

x-powered-by

x驱动

Boolean

Enables the "X-Powered-By: Express" HTTP header.

启用"X-Powered-By，Express" HTTP 报头

true

Options for `trust proxy` setting

Type	Value
Boolean	If `true`, the client’s IP address is understood as the left-most entry in the `X-Forwarded-*` header. If `false`, the app is understood as directly facing the Internet and the client’s IP address is derived from `req.connection.remoteAddress`. This is the default setting.
IP addresses	An IP address, subnet, or an array of IP addresses, and subnets to trust. The following is the list of pre-configured subnet names. loopback - `127.0.0.1/8`, `::1/128`linklocal - `169.254.0.0/16`, `fe80::/10`uniquelocal - `10.0.0.0/8`, `172.16.0.0/12`, `192.168.0.0/16`, `fc00::/7` Set IP addresses in any of the following ways: app.set('trust proxy', 'loopback') // specify a single subnet app.set('trust proxy', 'loopback, 123.123.123.123') // specify a subnet and an address app.set('trust proxy', 'loopback, linklocal, uniquelocal') // specify multiple subnets as CSV app.set('trust proxy', ['loopback', 'linklocal', 'uniquelocal']) // specify multiple subnets as an array When specified, the IP addresses or the subnets are excluded from the address determination process, and the untrusted IP address nearest to the application server is determined as the client’s IP address.
Number	Trust the `n`th hop from the front-facing proxy server as the client.
Function	Custom trust implementation. Use this only if you know what you are doing. app.set('trust proxy', function (ip) { if (ip === '127.0.0.1' \|\| ip === '123.123.123.123') return true; // trusted IPs else return false; })

Options for `etag` setting

Type	Value
Boolean	`true` enables weak ETag. This is the default setting.`false` disables ETag altogether.
String	If "strong", enables strong ETag.If "weak", enables weak ETag.
Function	Custom ETag function implementation. Use this only if you know what you are doing. app.set('etag', function (body, encoding) { return generateHash(body, encoding); // consider the function is defined })

http://www.expressjs.com.cn/4x/api.html#app.set （English版本）

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