add jdbc url parser for adding for database information to the trace

[wuyupengwoaini]

To fix https://github.com/opentracing-contrib/java-spring-cloud/issues/173 I think it is better to add the feature of paring the jdbc url here than to add the feature to the java-spring-cloud project.So I provided the ability to parse jdbc url Here.

But it also brings a problem that almost very databse url is different,so we need to provided more parser.Now i provided four parser (mysql ,oracle ,h2,postgresql)

[wuyupengwoaini]

@pavolloffay @malafeev please help me to review it

[malafeev]

tests failed

[wuyupengwoaini]

tests failed

fixed

[malafeev]

if we

• don't have a parser for some database

or

• parser failed due to jdbc driver can support several forms of url

how stable is instrumentation? I'm afraid that we can break user's application or spans will contain less information than now.

[coveralls]

Pull Request Test Coverage Report for Build 105

• 201 of 213 (94.37%) changed or added relevant lines in 10 files are covered.
• 3 unchanged lines in 2 files lost coverage.
• Overall coverage increased (+16.7%) to 42.509%

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Changes Missing Coverage	Covered Lines	Changed/Added Lines	%
src/main/java/io/opentracing/contrib/jdbc/ConnectionInfo.java	19	20	95.0%
src/main/java/io/opentracing/contrib/jdbc/parser/H2URLParser.java	32	33	96.97%
src/main/java/io/opentracing/contrib/jdbc/parser/OracleURLParser.java	56	57	98.25%
src/main/java/io/opentracing/contrib/jdbc/parser/URLParser.java	18	27	66.67%
<!--	Total:	201	213	94.37%	-->

Files with Coverage Reduction	New Missed Lines	%
src/main/java/io/opentracing/contrib/jdbc/JdbcTracingUtils.java	1	91.18%
src/main/java/io/opentracing/contrib/jdbc/ConnectionInfo.java	2	91.43%
<!--	Total:	3		-->

Totals
Change from base Build 101:	16.7%
Covered Lines:	349
Relevant Lines:	821

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💛 - Coveralls

[wuyupengwoaini]

Now, if we don't have a parser for some database,URLParser wil return a ConnectionInfo.UNKNOWN_CONNECTION_INFO

and I provided a method to the user to register custom parser.

This instrumentation method is Borrowed from skywalking,so I think it is stable enough

[wuyupengwoaini]

The safe way of not breaking user's application is catching the exception of parsing url and return a ConnectionInfo.UNKNOWN_CONNECTION_INFO

what about you @malafeev

[malafeev]

I agree, that's the more safe way.

[wuyupengwoaini]

I catch all exception but I am not sure to add log or do nothing. And I remove the restrict of adding same parser to let user custome there own parser

@malafeev

[malafeev]

thanks @wuyupengwoaini, I think we need to add log message using java.util.logging, at least for debugging