Java¶

作者： 刘锐、宋龙奇

Introduction¶

Here we mainly introduce some extended functions of DDTrace-Java. List of main features:

• JDBC SQL obfuscation
• xxl-jobs
• Dubbo 2/3
• Thrift
• RocketMQ
• log pattern
• hsf
• Support Alibaba Cloud RocketMQ 5.0
• redis trace parameters
• Get the input parameter information of a specific function
• MongoDB obfuscation
• Supported DM8 Database
• Supported trace-128-bit-id
• Supported Apache Pulsar MQ
• Support placing trace_id in the response header
• Support putting the requested header information into the span tags
• Support add HTTP Response Body information in the trace data

HTTP Response Body in the trace¶

The command line opening parameter is -Ddd.trace.response.body.enabled=true, the corresponding environment variable is DD_TRACE_RESPONSE_BODY_ENABLED=true, and the default value is false.

Since getting response body causes damage to response, the encoding adjustment of response body defaults to utf-8. If you need to adjust it, use -Ddd.trace.response.body.encoding=gbk.

DDTrace supported version: v1.30.1

Tracing Header¶

The link information will put the header information of the request and response into the tag.The default state is off. If it needs to be turned on, add the parameter -Ddd.trace.headers.enabled=true during startup.

DDTrace supported version: v1.25.2

supported trace-128-id¶

Datakit-1.8.0 DDTrace-1.4.0-guance

The default trace-id of the DDTrace agent is 64 bit, and the Datakit also supports 64 bit trace-id in the received link data. Starting from v1.11.0, it supports the W3C protocol and supports receiving 128 bit trace-id. However, the trace id sent to the link is still 64 bit.

To this end, secondary development was carried out on the observation cloud, which incorporated trace_128_bit_id is placed in the link data and sent to the Datakit, the DDTrace and OTEL links can be concatenated.

how to config:

# open trace.128.bit, and use W3C propagation.
-Ddd.trace.128.bit.traceid.generation.enabled=true -Ddd.trace.propagation.style=tracecontext

This is GitHub issue

At present, only DDTrace and OTEL are connected in series, and there is currently no testing with other APM manufacturers.

supported MongoDB obfuscation¶

Use startup parameter -DDd.mongo.obfuscation=true or environment variable DD_MONGO_OBFUSION Turn on desensitization. This way, a specific command can be seen from the observation cloud.

Currently, the types that can achieve desensitization include Int32, Int64, Boolean, Double, and String. The remaining ones have no reference significance, so they are currently not supported.

supported version：

• all

DDTrace supported version: v1.12.1

supported DM8 Database¶

Add DM8 Database trace information. supported version：

• v8

Get the input parameter information of a specific function¶

Specific function mainly refers to the function specified by the business to obtain the corresponding input parameters.

Specific functions need to be defined and declared through specific parameters. Currently, ddtrace provides two ways to trace specific functions:

1. Marked by startup parameters: -Ddd.trace.methods ，reference documents： Class or method injection Trace

2. By introducing the SDK, use @Trace to mark, refer to the document function level burying point

After the declaration is made in the above way, the corresponding method will be marked as trace, and the corresponding Span information will be generated at the same time, including the input parameter information of the function (input parameter name, type, value).

DDTrace supported version： v1.12.1

ddtrace agent default port¶

ddtrace changes the default remote port 8126 to 9529.

redis command args¶

The Resource in the redis link will only display redis.command information, and will not display parameter information.

Enable this function: start the command to add the environment variable -Ddd.redis.command.args, and a tag will be added in the details of the observation cloud link: redis.command.args=key val.

Supported version: redis1.4.0 and above.

log pattern¶

By modifying the default log pattern, application logs and links are correlated, thereby reducing deployment costs. The logging framework log4j2 is currently supported, but logback is not currently supported.

-Ddd.logs.pattern like -Ddd.logs.pattern="%d{yyyy-MM-dd HH:mm:ss.SSS} [%thread] %-5level %logger - %X{dd.service} %X{dd.trace_id} %X{dd.span_id} - %msg%n"

supported version： log4j2

SQL obfuscation¶

By default, DDTrace converts parameters in SQL to ?, which prevents users from obtaining more accurate information when troubleshooting. The new probe will extract the parameters into the Trace data separately in Key-Value mode, which is convenient for users to view.

In the Java startup command, add the following command line parameters to enable this function:

-Ddd.jdbc.sql.obfuscation=true

Display of results¶

Take setString() as an example. The location of the new probe is at java.sql.PreparedStatement/setString(key, value)。

There are two parameters here, the first one is the subscript of the placeholder parameter (starting from 1), the second one is the string type, after calling the setString(index, value) method, the corresponding string value will be stored into the span.

After the SQL is executed, this map will be filled into the Span. The final data structure format is as follows:

"meta": {
  "component":
  "java-jdbc-prepared_statement",

  "db.instance":"tmalldemodb",
  "db.operation":"INSERT",

  "db.sql.origin":"INSERT product
    (product_id,
     product_name,
     product_title,
     product_price,
     product_sale_price,
     product_create_date,
     product_isEnabled,
     product_category_id)
    VALUES(null, ?, ?, ?, ?, ?, ?, ?)",

  "db.type":"mysql",
  "db.user":"root",
  "env":"test",
  "peer.hostname":"49.232.153.84",
  "span.kind":"client",
  "thread.name": "http-nio-8080-exec-6",

  "sql.params.index_1":"图书",
  "sql.params.index_2":"十万个为什么",
  "sql.params.index_3":"100.0",
  "sql.params.index_4":"99.0",
  "sql.params.index_5":"2022-11-10 14:08:21",
  "sql.params.index_6":"0",
  "sql.params.index_7":"16"
}

supported version： Version 2.3 and above are currently supported.

DDTrace supported version：v0.113.0

Dubbo supported¶

Dubbo is an open source framework of Alibaba Cloud, which currently supports Dubbo2 and Dubbo3.

supported version: Dubbo2: 2.7.0 and above, Dubbo3 has no version restrictions.

RocketMQ¶

RocketMQ is an open source message queuing framework contributed by Alibaba Cloud to the Apache Foundation. Note: Alibaba Cloud RocketMQ 5.0 and the Apache Foundation are two different libraries.

There is a difference when referencing the library, the apache RocketMQ artifactId: rocketmq-client, and the artifactId of Alibaba Cloud RocketMQ 5.0: rocketmq-client-java

supported version: Currently supports version 4.8.0 and above. Alibaba Cloud RocketMQ service supports version 5.0 and above.

Thrift supported¶

Thrift is an apache project. Some customers use thrift RPC for communication in the project, and we support it.

supported version: 0.9.3 and above.

batch injection DDTrace-Java Agent¶

The native DDTrace-Java batch injection method has certain flaws, and does not support dynamic parameter injection (such as -Ddd.agent=xxx, -Ddd.agent.port=yyy, etc.).

The extended DDTrace-Java adds dynamic parameter injection. For specific usage, see here