[Bug]: span tags of type int64 may lose precision

[yurishkuro]

What happened?

UI shows span tag values with a precision loss (jaegertracing/jaeger-ui#982)

Steps to reproduce

1. save a trace with span tag of type int64 that has a very large value
2. view the trace in the UI - it may show rounded up value ([Bug]: span tags of type int64 may lose precision jaeger-ui#982)

Expected behavior

UI should show accurate value stored in the backend.

The issue stems from Javascript not being able to represent full resolution of 64-bit integers. The common workaround for that is to send large numbers as string values. The relevant code is here:

jaeger/model/converter/json/from_domain.go

Line 124 in 2e8c6b2

value = kv.Int64()

Relevant log output

No response

Screenshot

No response

Additional context

The fix should include a fixture with large-enough value that would lose precision when parsed by Javascript.

Jaeger backend version

No response

SDK

No response

Pipeline

No response

Stogage backend

No response

Operating system

No response

Deployment model

No response

Deployment configs

No response

[shubbham1215]

Hi @yurishkuro , as part of my academics, I am looking forward to contribute for an open source project and my first Pull Request. Can I contribute to this issue? You can also assign me #3949 as that also looks a good first issue.

[yurishkuro]

You are welcome to.

[shubbham1215]

Could you please assign the issues to me? I have to send a screenshot of the issues showing that I have been assigned the issues.

[yurishkuro]

assigned

[shubbham1215]

Hi @yurishkuro , I have got a basic understanding of jaeger after going through some of your videos on Youtube. I have built jaeger from source and able to run the demo of hotrod example. But I am not exactly sure how to send a span tag of type int64 that has a very large value. Could you please elaborate more on this?Thanks.

[yurishkuro]

There is a generator in cmd/tracegen, you can add a code there to set a span tag with large int64 value (bigger than the JavaScript limit of 2^53 – 1, e.g. val := int64(1) << 55)

[yurishkuro]

You could also just add that tag to a text fixture and make sure it is converted to a string value in the ui-json output

model/converter/json/fixtures/domain_01.json

[shubbham1215]

Will be raising a PR within the coming week

[shubbham1215]

I am new to Go language. I have managed to do this and seen that the large value is shown as a string in ui_01-actual.json
Is this the correct fix?

value = kv.Bool()
		case model.Int64Type:
			value = kv.Int64()
			if kv.Int64() > 9007199254740991 || kv.Int64() < -9007199254740991 {
				kv.VType = 0
				value = fmt.Sprintf("%v", value)
			}
		case model.Float64Type:

[yurishkuro]

yep, looks right, but use named constants

[shubbham1215]

Additional context

The fix should include a fixture with large-enough value that would lose precision when parsed by Javascript.

Where do I add this fixture? I added it in domain_01.json and ui_01.json but am getting below error after running the test TestFromDomain
Diff:
--- Expected
+++ Actual
@@ -65,5 +65,5 @@
{
- "key":"js_limit",
- "vType":"INT64",
- "vInt64":9223372036854775222
+ "key": "js_limit",
+ "type": "string",
+ "value": "9223372036854775222"
},
Test: TestFromDomain
FAIL
FAIL github.com/jaegertracing/jaeger/model/converter/json 0.005s

[yurishkuro]

those look like the right files. The failure seems to be from the type, not so much from the value.

[yurishkuro]

I recommend creating a WIP PR, it's easier to discuss there, when there's code.