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628 lines
25 KiB
Markdown
628 lines
25 KiB
Markdown
---
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toc_priority: 19
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toc_title: HTTP客户端
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---
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# HTTP客户端 {#http-interface}
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HTTP接口允许您在任何编程语言的任何平台上使用ClickHouse。我们使用它在Java和Perl以及shell脚本中工作。在其他部门中,HTTP接口用于Perl、Python和Go。HTTP接口比原生接口受到更多的限制,但它具有更好的兼容性。
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默认情况下,`clickhouse-server`会在`8123`端口上监控HTTP请求(这可以在配置中修改)。
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如果你发送了一个未携带任何参数的`GET /`请求,它会返回一个字符串 «Ok.»(结尾有换行)。可以将它用在健康检查脚本中。
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如果你发送了一个未携带任何参数的`GET /`请求,它返回响应码200和`OK`字符串定义,可在[Http服务响应配置](../operations/server-configuration-parameters/settings.md#server_configuration_parameters-http_server_default_response)定义(在末尾添加换行)
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``` bash
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$ curl 'http://localhost:8123/'
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Ok.
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```
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通过URL中的 `query` 参数来发送请求,或者发送POST请求,或者将查询的开头部分放在URL的`query`参数中,其他部分放在POST中(我们会在后面解释为什么这样做是有必要的)。URL的大小会限制在16KB,所以发送大型查询时要时刻记住这点。
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如果请求成功,将会收到200的响应状态码和响应主体中的结果。
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如果发生了某个异常,将会收到500的响应状态码和响应主体中的异常描述信息。
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当使用GET方法请求时,`readonly`会被设置。换句话说,若要作修改数据的查询,只能发送POST方法的请求。可以将查询通过POST主体发送,也可以通过URL参数发送。
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示例:
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``` bash
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$ curl 'http://localhost:8123/?query=SELECT%201'
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1
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$ wget -nv -O- 'http://localhost:8123/?query=SELECT 1'
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1
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$ echo -ne 'GET /?query=SELECT%201 HTTP/1.0\r\n\r\n' | nc localhost 8123
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HTTP/1.0 200 OK
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Date: Wed, 27 Nov 2019 10:30:18 GMT
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Connection: Close
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Content-Type: text/tab-separated-values; charset=UTF-8
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X-ClickHouse-Server-Display-Name: clickhouse.ru-central1.internal
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X-ClickHouse-Query-Id: 5abe861c-239c-467f-b955-8a201abb8b7f
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X-ClickHouse-Summary: {"read_rows":"0","read_bytes":"0","written_rows":"0","written_bytes":"0","total_rows_to_read":"0"}
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1
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```
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可以看到,curl 命令由于空格需要 URL 转义,所以不是很方便。尽管 wget 命令对url做了 URL 转义,但我们并不推荐使用他,因为在 HTTP 1.1 协议下使用 keep-alive 和 Transfer-Encoding: chunked 头部设置它并不能很好的工作。
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``` bash
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$ echo 'SELECT 1' | curl 'http://localhost:8123/' --data-binary @-
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1
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$ echo 'SELECT 1' | curl 'http://localhost:8123/?query=' --data-binary @-
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1
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$ echo '1' | curl 'http://localhost:8123/?query=SELECT' --data-binary @-
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1
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```
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如您所见,curl有些不方便,因为空格必须进行URL转义。
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尽管wget本身会对所有内容进行转义,但我们不推荐使用它,因为在使用keepalive和传输编码chunked时,它在HTTP 1.1上不能很好地工作。
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``` bash
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$ echo 'SELECT 1' | curl 'http://localhost:8123/' --data-binary @-
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1
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$ echo 'SELECT 1' | curl 'http://localhost:8123/?query=' --data-binary @-
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1
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$ echo '1' | curl 'http://localhost:8123/?query=SELECT' --data-binary @-
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1
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```
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如果部分查询是在参数中发送的,部分是在POST中发送的,则在这两个数据部分之间插入换行。
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错误示例:
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``` bash
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$ echo 'ECT 1' | curl 'http://localhost:8123/?query=SEL' --data-binary @-
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Code: 59, e.displayText() = DB::Exception: Syntax error: failed at position 0: SEL
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ECT 1
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, expected One of: SHOW TABLES, SHOW DATABASES, SELECT, INSERT, CREATE, ATTACH, RENAME, DROP, DETACH, USE, SET, OPTIMIZE., e.what() = DB::Exception
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```
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默认情况下,返回的数据是`TabSeparated`格式的,更多信息,见[Formats](../interfaces/formats/)部分。
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您可以使用查询的FORMAT子句来设置其他格式。
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另外,还可以使用`default_format`URL参数或`X-ClickHouse-Format`头来指定TabSeparated之外的默认格式。
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``` bash
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$ echo 'SELECT 1 FORMAT Pretty' | curl 'http://localhost:8123/?' --data-binary @-
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┏━━━┓
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┃ 1 ┃
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┡━━━┩
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│ 1 │
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└───┘
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```
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INSERT必须通过POST方法来插入数据。在这种情况下,您可以在URL参数中编写查询的开始部分,并使用POST传递要插入的数据。例如,要插入的数据可以是来自MySQL的一个以tab分隔的存储。通过这种方式,INSERT查询替换了从MySQL查询的LOAD DATA LOCAL INFILE。
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示例: 创建一个表:
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``` bash
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$ echo 'CREATE TABLE t (a UInt8) ENGINE = Memory' | curl 'http://localhost:8123/' --data-binary @-
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```
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使用类似INSERT的查询来插入数据:
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``` bash
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$ echo 'INSERT INTO t VALUES (1),(2),(3)' | curl 'http://localhost:8123/' --data-binary @-
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```
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数据可以从查询中单独发送:
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``` bash
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$ echo '(4),(5),(6)' | curl 'http://localhost:8123/?query=INSERT%20INTO%20t%20VALUES' --data-binary @-
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```
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您可以指定任何数据格式。`Values`格式与将INSERT写入`t`值时使用的格式相同:
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``` bash
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$ echo '(7),(8),(9)' | curl 'http://localhost:8123/?query=INSERT%20INTO%20t%20FORMAT%20Values' --data-binary @-
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```
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若要插入tab分割的数据,需要指定对应的格式:
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``` bash
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$ echo -ne '10\n11\n12\n' | curl 'http://localhost:8123/?query=INSERT%20INTO%20t%20FORMAT%20TabSeparated' --data-binary @-
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```
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从表中读取内容。由于查询处理是并行的,数据以随机顺序输出。
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``` bash
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$ curl 'http://localhost:8123/?query=SELECT%20a%20FROM%20t'
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7
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8
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9
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10
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11
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12
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1
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2
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3
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4
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5
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6
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```
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删除表:
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``` bash
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$ echo 'DROP TABLE t' | curl 'http://localhost:8123/' --data-binary @-
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```
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成功请求后并不会返回数据,返回一个空的响应体。
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在传输数据时,可以使用ClickHouse内部压缩格式。压缩的数据具有非标准格式,您需要使用特殊的`clickhouse-compressor`程序来处理它(它是与`clickhouse-client`包一起安装的)。为了提高数据插入的效率,您可以通过使用[http_native_compression_disable_checksumming_on_decompress](../operations/settings/settings.md#settings-http_native_compression_disable_checksumming_on_decompress)设置禁用服务器端校验。
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如果在URL中指定了`compress=1`,服务会返回压缩的数据。
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如果在URL中指定了`decompress=1`,服务会解压通过POST方法发送的数据。
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您也可以选择使用[HTTP compression](https://en.wikipedia.org/wiki/HTTP_compression)。发送一个压缩的POST请求,附加请求头`Content-Encoding: compression_method`。为了使ClickHouse响应,您必须附加`Accept-Encoding: compression_method`。ClickHouse支持`gzip`,`br`和`deflate` [compression methods](https://en.wikipedia.org/wiki/HTTP_compression#Content-Encoding_tokens)。要启用HTTP压缩,必须使用ClickHouse[启用Http压缩](../operations/settings/settings.md#settings-enable_http_compression)配置。您可以在[Http zlib压缩级别](#settings-http_zlib_compression_level)设置中为所有压缩方法配置数据压缩级别。
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您可以使用它在传输大量数据时减少网络流量,或者创建立即压缩的转储。
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通过压缩发送数据的例子:
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``` bash
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#Sending data to the server:
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$ curl -vsS "http://localhost:8123/?enable_http_compression=1" -d 'SELECT number FROM system.numbers LIMIT 10' -H 'Accept-Encoding: gzip'
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#Sending data to the client:
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$ echo "SELECT 1" | gzip -c | curl -sS --data-binary @- -H 'Content-Encoding: gzip' 'http://localhost:8123/'
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```
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!!! note "警告"
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一些HTTP客户端可能会在默认情况下从服务器解压数据(使用`gzip`和`deflate`),即使您未正确地使用了压缩设置,您也可能会得到解压数据。
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您可以使用`database`URL参数或`X-ClickHouse-Database`头来指定默认数据库。
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``` bash
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$ echo 'SELECT number FROM numbers LIMIT 10' | curl 'http://localhost:8123/?database=system' --data-binary @-
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0
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1
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2
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3
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4
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5
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6
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7
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8
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9
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```
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默认情况下,在服务器设置中注册的数据库被用作默认数据库。默认情况下,它是名为`default`的数据库。或者,您可以始终在表名之前使用点来指定数据库。
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用户名和密码可以通过以下三种方式指定:
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1. 通过HTTP Basic Authentication。示例:
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<!-- -->
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``` bash
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$ echo 'SELECT 1' | curl 'http://user:password@localhost:8123/' -d @-
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```
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1. 通过URL参数中的`user`和`password`。示例:
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<!-- -->
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``` bash
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$ echo 'SELECT 1' | curl 'http://localhost:8123/?user=user&password=password' -d @-
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```
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1. 使用`X-ClickHouse-User`或`X-ClickHouse-Key`头指定,示例:
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<!-- -->
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``` bash
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$ echo 'SELECT 1' | curl -H 'X-ClickHouse-User: user' -H 'X-ClickHouse-Key: password' 'http://localhost:8123/' -d @-
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```
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如果未指定用户名,则使用`default`。如果未指定密码,则使用空密码。
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您还可以使用URL参数来指定处理单个查询或整个设置配置文件的任何设置。例子:`http://localhost:8123/?profile=web&max_rows_to_read=1000000000&query=SELECT+1`
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更多信息,详见[设置](../operations/settings/index.md#settings)部分。
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``` bash
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$ echo 'SELECT number FROM system.numbers LIMIT 10' | curl 'http://localhost:8123/?' --data-binary @-
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0
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1
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2
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3
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4
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5
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6
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7
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8
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9
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```
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有关其他参数的信息,请参考`SET`一节。
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类似地,您可以在HTTP协议中使用ClickHouse会话。为此,需要向请求添加`session_id`GET参数。您可以使用任何字符串作为会话ID。默认情况下,会话在60秒不活动后终止。要更改此超时配置,请修改服务器配置中的`default_session_timeout`设置,或向请求添加`session_timeout`GET参数。要检查会话状态,使用`session_check=1`参数。一次只能在单个会话中执行一个查询。
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您可以在`X-ClickHouse-Progress`响应头中收到查询进度的信息。为此,启用[Http Header携带进度](../operations/settings/settings.md#settings-send_progress_in_http_headers)。示例:
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``` text
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X-ClickHouse-Progress: {"read_rows":"2752512","read_bytes":"240570816","total_rows_to_read":"8880128"}
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X-ClickHouse-Progress: {"read_rows":"5439488","read_bytes":"482285394","total_rows_to_read":"8880128"}
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X-ClickHouse-Progress: {"read_rows":"8783786","read_bytes":"819092887","total_rows_to_read":"8880128"}
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```
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显示字段信息:
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- `read_rows` — 读取的行数。
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- `read_bytes` — 读取的数据字节数。
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- `total_rows_to_read` — 读取的数据总行数。
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- `written_rows` — 写入数据行数。
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- `written_bytes` — 写入数据字节数。
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如果HTTP连接丢失,运行的请求不会自动停止。解析和数据格式化是在服务器端执行的,使用Http连接可能无效。
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可选的`query_id`参数可能当做query ID传入(或者任何字符串)。更多信息,详见[replace_running_query](../operations/settings/settings.md)部分。
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可选的`quota_key`参数可能当做quota key传入(或者任何字符串)。更多信息,详见[Quotas](../operations/quotas.md#quotas)部分。
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HTTP接口允许传入额外的数据(外部临时表)来查询。更多信息,详见[外部数据查询处理](../engines/table-engines/special/external-data.md)部分。
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## 响应缓冲 {#response-buffering}
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可以在服务器端启用响应缓冲。提供了`buffer_size`和`wait_end_of_query`两个URL参数来达此目的。
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`buffer_size`决定了查询结果要在服务内存中缓冲多少个字节数据. 如果响应体比这个阈值大,缓冲区会写入到HTTP管道,剩下的数据也直接发到HTTP管道中。
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为了确保整个响应体被缓冲,可以设置`wait_end_of_query=1`。这种情况下,存入内存的数据会被缓冲到服务端的一个临时文件中。
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示例:
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``` bash
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$ curl -sS 'http://localhost:8123/?max_result_bytes=4000000&buffer_size=3000000&wait_end_of_query=1' -d 'SELECT toUInt8(number) FROM system.numbers LIMIT 9000000 FORMAT RowBinary'
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```
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查询请求响应状态码和HTTP头被发送到客户端后,若发生查询处理出错,使用缓冲区可以避免这种情况的发生。在这种情况下,响应主体的结尾会写入一条错误消息,而在客户端,只能在解析阶段检测到该错误。
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### 查询参数 {#cli-queries-with-parameters}
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您可以使用参数创建查询,并通过相应的HTTP请求参数为它们传递值。有关更多信息,请参见[CLI查询参数](../interfaces/cli.md#cli-queries-with-parameters)。
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### 示例 {#example}
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``` bash
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$ curl -sS "<address>?param_id=2¶m_phrase=test" -d "SELECT * FROM table WHERE int_column = {id:UInt8} and string_column = {phrase:String}"
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```
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## 特定的HTTP接口 {#predefined_http_interface}
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ClickHouse通过HTTP接口支持特定的查询。例如,您可以如下所示向表写入数据:
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``` bash
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$ echo '(4),(5),(6)' | curl 'http://localhost:8123/?query=INSERT%20INTO%20t%20VALUES' --data-binary @-
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```
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ClickHouse还支持预定义的HTTP接口,可以帮助您更容易与第三方工具集成,如[Prometheus Exporter](https://github.com/percona-lab/clickhouse_exporter).
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示例:
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- 首先,将此部分添加到服务器配置文件中:
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<!-- -->
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``` xml
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<http_handlers>
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<rule>
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<url>/predefined_query</url>
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<methods>POST,GET</methods>
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<handler>
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<type>predefined_query_handler</type>
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<query>SELECT * FROM system.metrics LIMIT 5 FORMAT Template SETTINGS format_template_resultset = 'prometheus_template_output_format_resultset', format_template_row = 'prometheus_template_output_format_row', format_template_rows_between_delimiter = '\n'</query>
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</handler>
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</rule>
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<rule>...</rule>
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<rule>...</rule>
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</http_handlers>
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```
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- 请求Prometheus格式的URL以获取数据:
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<!-- -->
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``` bash
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$ curl -v 'http://localhost:8123/predefined_query'
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* Trying ::1...
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* Connected to localhost (::1) port 8123 (#0)
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> GET /predefined_query HTTP/1.1
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> Host: localhost:8123
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> User-Agent: curl/7.47.0
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> Accept: */*
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>
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< HTTP/1.1 200 OK
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< Date: Tue, 28 Apr 2020 08:52:56 GMT
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< Connection: Keep-Alive
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< Content-Type: text/plain; charset=UTF-8
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< X-ClickHouse-Server-Display-Name: i-mloy5trc
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< Transfer-Encoding: chunked
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< X-ClickHouse-Query-Id: 96fe0052-01e6-43ce-b12a-6b7370de6e8a
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< X-ClickHouse-Format: Template
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< X-ClickHouse-Timezone: Asia/Shanghai
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< Keep-Alive: timeout=3
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< X-ClickHouse-Summary: {"read_rows":"0","read_bytes":"0","written_rows":"0","written_bytes":"0","total_rows_to_read":"0"}
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<
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# HELP "Query" "Number of executing queries"
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# TYPE "Query" counter
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"Query" 1
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# HELP "Merge" "Number of executing background merges"
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# TYPE "Merge" counter
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"Merge" 0
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# HELP "PartMutation" "Number of mutations (ALTER DELETE/UPDATE)"
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# TYPE "PartMutation" counter
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"PartMutation" 0
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# HELP "ReplicatedFetch" "Number of data parts being fetched from replica"
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# TYPE "ReplicatedFetch" counter
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"ReplicatedFetch" 0
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# HELP "ReplicatedSend" "Number of data parts being sent to replicas"
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# TYPE "ReplicatedSend" counter
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"ReplicatedSend" 0
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* Connection #0 to host localhost left intact
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* Connection #0 to host localhost left intact
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```
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|
||
正如您从示例中看到的,如果在`config.xml`文件中配置了`http_handlers`,并且`http_handlers`可以包含许多`规则`。ClickHouse将把接收到的HTTP请求与`rule`中的预定义类型进行匹配,第一个匹配的将运行处理程序。如果匹配成功,ClickHouse将执行相应的预定义查询。
|
||
|
||
现在`rule`可以配置`method`, `header`, `url`, `handler`:
|
||
- `method` 负责匹配HTTP请求的方法部分。 `method`完全符合HTTP协议中[method](https://developer.mozilla.org/en-US/docs/Web/HTTP/Methods)的定义。这是一个可选的配置。如果它没有在配置文件中定义,那么它与HTTP请求的方法部分不匹配。
|
||
|
||
- `url` 负责匹配HTTP请求的URL部分。它匹配[RE2](https://github.com/google/re2)正则表达式。这是一个可选的配置。如果配置文件中没有定义它,则它与HTTP请求的URL部分不匹配。
|
||
|
||
- `headers` 负责匹配HTTP请求的头部分。它与RE2的正则表达式兼容。这是一个可选的配置。如果它没有在配置文件中定义,那么它与HTTP请求的头部分不匹配。
|
||
|
||
- `handler` 包含主要的处理部分。现在`handler`可以配置`type`, `status`, `content_type`, `response_content`, `query`, `query_param_name`。
|
||
`type` 目前支持三种类型:[特定查询](#predefined_query_handler), [动态查询](#dynamic_query_handler), [static](#static).
|
||
|
||
- `query` — 使用`predefined_query_handler`类型,在调用处理程序时执行查询。
|
||
|
||
- `query_param_name` — 与`dynamic_query_handler`类型一起使用,提取并执行HTTP请求参数中与`query_param_name`值对应的值。
|
||
|
||
- `status` — 与`static`类型一起使用,响应状态代码。
|
||
|
||
- `content_type` — 与`static`类型一起使用,响应信息[content-type](https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/Content-Type)。
|
||
|
||
- `response_content` — 与`static`类型一起使用,响应发送给客户端的内容,当使用前缀`file://`或`config://`时,从发送给客户端的文件或配置中查找内容。
|
||
|
||
接下来是不同`type`的配置方法。
|
||
|
||
### 特定查询 {#predefined_query_handler}
|
||
|
||
`predefined_query_handler` 支持设置`Settings`和`query_params`参数。您可以将`query`配置为`predefined_query_handler`类型。
|
||
|
||
`query` 是一个预定义的`predefined_query_handler`查询,它由ClickHouse在匹配HTTP请求并返回查询结果时执行。这是一个必须的配置。
|
||
|
||
以下是定义的[max_threads](../operations/settings/settings.md#settings-max_threads)和`max_alter_threads`设置, 然后查询系统表以检查这些设置是否设置成功。
|
||
|
||
示例:
|
||
|
||
``` xml
|
||
<http_handlers>
|
||
<rule>
|
||
<url><![CDATA[/query_param_with_url/\w+/(?P<name_1>[^/]+)(/(?P<name_2>[^/]+))?]]></url>
|
||
<method>GET</method>
|
||
<headers>
|
||
<XXX>TEST_HEADER_VALUE</XXX>
|
||
<PARAMS_XXX><![CDATA[(?P<name_1>[^/]+)(/(?P<name_2>[^/]+))?]]></PARAMS_XXX>
|
||
</headers>
|
||
<handler>
|
||
<type>predefined_query_handler</type>
|
||
<query>SELECT value FROM system.settings WHERE name = {name_1:String}</query>
|
||
<query>SELECT name, value FROM system.settings WHERE name = {name_2:String}</query>
|
||
</handler>
|
||
</rule>
|
||
</http_handlers>
|
||
```
|
||
|
||
``` bash
|
||
$ curl -H 'XXX:TEST_HEADER_VALUE' -H 'PARAMS_XXX:max_threads' 'http://localhost:8123/query_param_with_url/1/max_threads/max_alter_threads?max_threads=1&max_alter_threads=2'
|
||
1
|
||
max_alter_threads 2
|
||
```
|
||
|
||
!!! note "警告"
|
||
在一个`predefined_query_handler`中,只支持insert类型的一个`查询`。
|
||
|
||
### 动态查询 {#dynamic_query_handler}
|
||
|
||
`dynamic_query_handler`时,查询以HTTP请求参数的形式编写。区别在于,在`predefined_query_handler`中,查询是在配置文件中编写的。您可以在`dynamic_query_handler`中配置`query_param_name`。
|
||
|
||
ClickHouse提取并执行与HTTP请求URL中的`query_param_name`值对应的值。`query_param_name`的默认值是`/query`。这是一个可选的配置。如果配置文件中没有定义,则不会传入参数。
|
||
|
||
为了试验这个功能,示例定义了[max_threads](../operations/settings/settings.md#settings-max_threads)和`max_alter_threads`,`queries`设置是否成功的值。
|
||
|
||
示例:
|
||
|
||
``` xml
|
||
<http_handlers>
|
||
<rule>
|
||
<headers>
|
||
<XXX>TEST_HEADER_VALUE_DYNAMIC</XXX> </headers>
|
||
<handler>
|
||
<type>dynamic_query_handler</type>
|
||
<query_param_name>query_param</query_param_name>
|
||
</handler>
|
||
</rule>
|
||
</http_handlers>
|
||
```
|
||
|
||
``` bash
|
||
$ curl -H 'XXX:TEST_HEADER_VALUE_DYNAMIC' 'http://localhost:8123/own?max_threads=1&max_alter_threads=2¶m_name_1=max_threads¶m_name_2=max_alter_threads&query_param=SELECT%20name,value%20FROM%20system.settings%20where%20name%20=%20%7Bname_1:String%7D%20OR%20name%20=%20%7Bname_2:String%7D'
|
||
max_threads 1
|
||
max_alter_threads 2
|
||
```
|
||
|
||
### static {#static}
|
||
|
||
`static`可以返回[content_type](https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/Content-Type), [status](https://developer.mozilla.org/en-US/docs/Web/HTTP/Status)和`response_content`。`response_content`可以返回指定的内容。
|
||
|
||
示例:
|
||
|
||
返回信息.
|
||
|
||
``` xml
|
||
<http_handlers>
|
||
<rule>
|
||
<methods>GET</methods>
|
||
<headers><XXX>xxx</XXX></headers>
|
||
<url>/hi</url>
|
||
<handler>
|
||
<type>static</type>
|
||
<status>402</status>
|
||
<content_type>text/html; charset=UTF-8</content_type>
|
||
<response_content>Say Hi!</response_content>
|
||
</handler>
|
||
</rule>
|
||
<http_handlers>
|
||
```
|
||
|
||
``` bash
|
||
$ curl -vv -H 'XXX:xxx' 'http://localhost:8123/hi'
|
||
* Trying ::1...
|
||
* Connected to localhost (::1) port 8123 (#0)
|
||
> GET /hi HTTP/1.1
|
||
> Host: localhost:8123
|
||
> User-Agent: curl/7.47.0
|
||
> Accept: */*
|
||
> XXX:xxx
|
||
>
|
||
< HTTP/1.1 402 Payment Required
|
||
< Date: Wed, 29 Apr 2020 03:51:26 GMT
|
||
< Connection: Keep-Alive
|
||
< Content-Type: text/html; charset=UTF-8
|
||
< Transfer-Encoding: chunked
|
||
< Keep-Alive: timeout=3
|
||
< X-ClickHouse-Summary: {"read_rows":"0","read_bytes":"0","written_rows":"0","written_bytes":"0","total_rows_to_read":"0"}
|
||
<
|
||
* Connection #0 to host localhost left intact
|
||
Say Hi!%
|
||
```
|
||
|
||
从配置中查找发送到客户端的内容。
|
||
|
||
``` xml
|
||
<get_config_static_handler><![CDATA[<html ng-app="SMI2"><head><base href="http://ui.tabix.io/"></head><body><div ui-view="" class="content-ui"></div><script src="http://loader.tabix.io/master.js"></script></body></html>]]></get_config_static_handler>
|
||
|
||
<http_handlers>
|
||
<rule>
|
||
<methods>GET</methods>
|
||
<headers><XXX>xxx</XXX></headers>
|
||
<url>/get_config_static_handler</url>
|
||
<handler>
|
||
<type>static</type>
|
||
<response_content>config://get_config_static_handler</response_content>
|
||
</handler>
|
||
</rule>
|
||
</http_handlers>
|
||
```
|
||
|
||
``` bash
|
||
$ curl -v -H 'XXX:xxx' 'http://localhost:8123/get_config_static_handler'
|
||
* Trying ::1...
|
||
* Connected to localhost (::1) port 8123 (#0)
|
||
> GET /get_config_static_handler HTTP/1.1
|
||
> Host: localhost:8123
|
||
> User-Agent: curl/7.47.0
|
||
> Accept: */*
|
||
> XXX:xxx
|
||
>
|
||
< HTTP/1.1 200 OK
|
||
< Date: Wed, 29 Apr 2020 04:01:24 GMT
|
||
< Connection: Keep-Alive
|
||
< Content-Type: text/plain; charset=UTF-8
|
||
< Transfer-Encoding: chunked
|
||
< Keep-Alive: timeout=3
|
||
< X-ClickHouse-Summary: {"read_rows":"0","read_bytes":"0","written_rows":"0","written_bytes":"0","total_rows_to_read":"0"}
|
||
<
|
||
* Connection #0 to host localhost left intact
|
||
<html ng-app="SMI2"><head><base href="http://ui.tabix.io/"></head><body><div ui-view="" class="content-ui"></div><script src="http://loader.tabix.io/master.js"></script></body></html>%
|
||
```
|
||
|
||
从发送到客户端的文件中查找内容。
|
||
|
||
``` xml
|
||
<http_handlers>
|
||
<rule>
|
||
<methods>GET</methods>
|
||
<headers><XXX>xxx</XXX></headers>
|
||
<url>/get_absolute_path_static_handler</url>
|
||
<handler>
|
||
<type>static</type>
|
||
<content_type>text/html; charset=UTF-8</content_type>
|
||
<response_content>file:///absolute_path_file.html</response_content>
|
||
</handler>
|
||
</rule>
|
||
<rule>
|
||
<methods>GET</methods>
|
||
<headers><XXX>xxx</XXX></headers>
|
||
<url>/get_relative_path_static_handler</url>
|
||
<handler>
|
||
<type>static</type>
|
||
<content_type>text/html; charset=UTF-8</content_type>
|
||
<response_content>file://./relative_path_file.html</response_content>
|
||
</handler>
|
||
</rule>
|
||
</http_handlers>
|
||
```
|
||
|
||
``` bash
|
||
$ user_files_path='/var/lib/clickhouse/user_files'
|
||
$ sudo echo "<html><body>Relative Path File</body></html>" > $user_files_path/relative_path_file.html
|
||
$ sudo echo "<html><body>Absolute Path File</body></html>" > $user_files_path/absolute_path_file.html
|
||
$ curl -vv -H 'XXX:xxx' 'http://localhost:8123/get_absolute_path_static_handler'
|
||
* Trying ::1...
|
||
* Connected to localhost (::1) port 8123 (#0)
|
||
> GET /get_absolute_path_static_handler HTTP/1.1
|
||
> Host: localhost:8123
|
||
> User-Agent: curl/7.47.0
|
||
> Accept: */*
|
||
> XXX:xxx
|
||
>
|
||
< HTTP/1.1 200 OK
|
||
< Date: Wed, 29 Apr 2020 04:18:16 GMT
|
||
< Connection: Keep-Alive
|
||
< Content-Type: text/html; charset=UTF-8
|
||
< Transfer-Encoding: chunked
|
||
< Keep-Alive: timeout=3
|
||
< X-ClickHouse-Summary: {"read_rows":"0","read_bytes":"0","written_rows":"0","written_bytes":"0","total_rows_to_read":"0"}
|
||
<
|
||
<html><body>Absolute Path File</body></html>
|
||
* Connection #0 to host localhost left intact
|
||
$ curl -vv -H 'XXX:xxx' 'http://localhost:8123/get_relative_path_static_handler'
|
||
* Trying ::1...
|
||
* Connected to localhost (::1) port 8123 (#0)
|
||
> GET /get_relative_path_static_handler HTTP/1.1
|
||
> Host: localhost:8123
|
||
> User-Agent: curl/7.47.0
|
||
> Accept: */*
|
||
> XXX:xxx
|
||
>
|
||
< HTTP/1.1 200 OK
|
||
< Date: Wed, 29 Apr 2020 04:18:31 GMT
|
||
< Connection: Keep-Alive
|
||
< Content-Type: text/html; charset=UTF-8
|
||
< Transfer-Encoding: chunked
|
||
< Keep-Alive: timeout=3
|
||
< X-ClickHouse-Summary: {"read_rows":"0","read_bytes":"0","written_rows":"0","written_bytes":"0","total_rows_to_read":"0"}
|
||
<
|
||
<html><body>Relative Path File</body></html>
|
||
* Connection #0 to host localhost left intact
|
||
```
|
||
|
||
[来源文章](https://clickhouse.tech/docs/zh/interfaces/http_interface/) <!--hide-->
|