contrib: add support for github.com/go-pg/pg

[patriczek]

In this MR i would add gopg tracing.

Signed-off-by: Patrik Helia patashelia@gmail.com

[gbbr]

We need an example_test.go file too, along with documentation and copyright headers.

[gbbr]

CI should be better once you rebase on master.

[knusbaum]

Thanks for contributing this.

[patriczek]

Hi guys, thank you for your feedback, hope all your feedback are now fixed, if i missed something please let me know, i'll try to fix.

For now CI passed, hope everything is done.

[gbbr]

Thanks for making the changes. Left a few more comments.

[gbbr]

Please remember to add an example file as suggested in #686 (review)

[patriczek]

Please remember to add an example file as suggested in #686 (review)

Will add later.

[gbbr]

Thanks for making further changes. I hope you'll be patient with us until we go through a couple of iterations in the review process.

Can you lastly try out this integration with an actual application and perhaps post a screenshot of what the result would be in the Datadog application?

[patriczek]

We need an example_test.go file too, along with documentation and copyright headers.

I added example file.
I'm not sure, if i have correct imports, can you check it please?

[gbbr]

I left some comments on your example file but please spend some time and go through all comments because you have not addressed everything (e.g. @knusbaum's comments)

[patriczek]

I left some comments on your example file but please spend some time and go through all comments because you have not addressed everything (e.g. @knusbaum's comments)

Can you please point me what i missed? I think i did all changes suggested by @knusbaum

[gbbr]

For example this one: #686 (comment). Best way to not miss any is to just go through them one by one, address them, and once done resolve them on Github.

Please note that there will be more comments with regards to the docs and styling, I hope that's ok with you and you'll have the patience to go through them with us.

[knusbaum]

@patriczek, CI shows the issue with the package path/name:

# gopkg.in/DataDog/dd-trace-go.v1/contrib/go-pg
package gopkg.in/DataDog/dd-trace-go.v1/contrib/go-pg (test)
	imports gopkg.in/DataDog/dd-trace-go.v1/contrib/go-pg/pg: cannot find module providing package gopkg.in/DataDog/dd-trace-go.v1/contrib/go-pg/pg
FAIL	gopkg.in/DataDog/dd-trace-go.v1/contrib/go-pg [setup failed]

For the package to be gopkg.in/DataDog/dd-trace-go.v1/contrib/go-pg/pg, the files need to be under directory contrib/go-pg/pg/ rather than what you have currently: contrib/go-pg/

[patriczek]

@patriczek, CI shows the issue with the package path/name:

# gopkg.in/DataDog/dd-trace-go.v1/contrib/go-pg
package gopkg.in/DataDog/dd-trace-go.v1/contrib/go-pg (test)
	imports gopkg.in/DataDog/dd-trace-go.v1/contrib/go-pg/pg: cannot find module providing package gopkg.in/DataDog/dd-trace-go.v1/contrib/go-pg/pg
FAIL	gopkg.in/DataDog/dd-trace-go.v1/contrib/go-pg [setup failed]

For the package to be gopkg.in/DataDog/dd-trace-go.v1/contrib/go-pg/pg, the files need to be under directory contrib/go-pg/pg/ rather than what you have currently: contrib/go-pg/

Should by fixed, i forget push last commit from 2nd pc

[knusbaum]

Thank you for working through this with us, @patriczek
I have just a few more comments around the example. We should improve the language in the comments to make sure it's very clear for users. Please see our garyburd/redigo example for a good demonstration of a clear example with good documentation.

dd-trace-go/contrib/garyburd/redigo/example_test.go

Lines 19 to 39 in 9495abe

	// To start tracing Redis commands, use the TracedDial function to create a connection,
	// passing in a service name of choice.
	func Example() {
	c, err := redigotrace.Dial("tcp", "127.0.0.1:6379")
	if err != nil {
	log.Fatal(err)
	}
	// Emit spans per command by using your Redis connection as usual
	c.Do("SET", "vehicle", "truck")
	// Use a context to pass information down the call chain
	root, ctx := tracer.StartSpanFromContext(context.Background(), "parent.request",
	tracer.ServiceName("web"),
	tracer.ResourceName("/home"),
	)
	// When passed a context as the final argument, c.Do will emit a span inheriting from 'parent.request'
	c.Do("SET", "food", "cheese", ctx)
	root.Finish()
	}

[knusbaum]

Hi, @patriczek. Will you have time to finish this up? I think we're nearly there.

[patriczek]

Hi, @patriczek. Will you have time to finish this up? I think we're nearly there.

Hi, @knusbaum, i hope tomorrow i will have some spare time to finish it.

[gbbr]

This is great code-wise! Thanks for the effort. One last question about the example.

[gbbr]

Why? Won't it work without context? If not, let's correct the spelling a bit:

Suggested change

	// For correct tracing, must be query execute with context.
	// For queries to be traced, context must be used because ...

If it will, let's just remove this coment.

[gbbr]

Nice work! Thank you!

[knusbaum]

🎉