Feature Request: Bun Support

[diavrank]

Hi, I'm trying to run my app with Bun but I'm getting this error and it seems the root cause is the package of dd-trace. I know this is not your responsibility to fix this kind of issues, however, I wonder if there's any chance you take a look in case you can support the Bun project by fixing the problem from your side or giving feedback about what is the incompatibility issue with this library and Bun.

Expected behaviour

Start the Nestjs server successfully with Bun.

NPM script:

"start": "NODE_ENV=localdev nest start --watch --exec "bun run"",

Actual behaviour

It's throwing the following error when starting a Nest.js app:

[2:20:07 AM] Starting compilation in watch mode...

[2:20:24 AM] Found 0 errors. Watching for file changes.



error: Cannot find module "./hooks" from "[object Object]"

Steps to reproduce

1. Create a Nestjs app
2. Install the dependency ddt-trace with Bun 1.0.8
3. Execute bun start command:

Have the start script as: "start": "NODE_ENV=localdev nest start --watch --exec "bun run"",

Environment

• Operation system: Mac OS Sonoma
• Node.js version: v18.16.1 (But it was run with Bun 1.0.8)
• Tracer version: ^4.12.0" (Additionally, "nestjs-ddtrace": "^3.0.4",)
• Agent version: what is this?
• Relevant library versions: Bun 1.0.8

[diavrank]

Btw, I also reported the same issue in Bun repo https://github.com/oven-sh/bun/issues/6374

[Koka]

For anyone looking for a way to enable DD tracing in a Bun runtime - there's a (hacky) way to do so (see gist https://gist.github.com/Koka/f1801289b526eeb5853894cc4e3e747d)

Short summary - I had to monkey patch dogstatsd.CustomMetrics to avoid sending metrics through UDP (not supported by Bun runtime yet) and add a shim BlockList to node net module (blocklist is not supported by Bun runtime yet and shim is built in but detection doesn't play well with Bun)

Using this technique you can run functional APM tracing without any metrics being sent, and without any integrations, so you have to call tracer.trace manually

[Jarred-Sumner]

dd-trace should work in Bun as of Bun v1.1.6 (current: Bun v1.1.10)

Relevant PRs:

• https://github.com/oven-sh/bun/pull/10568
• https://github.com/oven-sh/bun/pull/7271

We manually tested it works when using Express and CommonJS. I don't think it supports tracing ESM imports, as we haven't implemented the Node.js loader API (though we do support a module loader API which works both with CommonJS & ESM without extra work to support both)

[hpx7]

Is there an issue for tracking support for tracing ESM imports?

[chin2km]

dd-trace should work in Bun as of Bun v1.1.6 (current: Bun v1.1.10)

Relevant PRs:

• final steps to getting dd-trace to work oven-sh/bun#10568
• UDP support oven-sh/bun#7271

We manually tested it works when using Express and CommonJS. I don't think it supports tracing ESM imports, as we haven't implemented the Node.js loader API (though we do support a module loader API which works both with CommonJS & ESM without extra work to support both)

Is there an example for this integration somewhere you could share please?

I followed the different options from the official Datadog documentation here, but no luck so far.

[rburgst]

any updates here?

[rburgst]

i got most of it working however, it appears that incoming http headers from a node based service are not being picked up, so in my APM traces I dont see the connection from node service -> bun service I am running elysia.js (https://elysiajs.com/) via bun. I can confirm that the x-datadog-* headers are being sent by the node server:

[na-ji]

Hello!

I tried to set up an app using Elysiajs in Bun too, and noticed that at least one plugin isn't working: the tcp plugin. When I start my application, the tracer in debug mode is logging this:

64 | function onError (err) {
65 |   const { formatted, cause } = getErrorLog(err)
66 | 
67 |   // calling twice logger.error() because Error cause is only available in nodejs v16.9.0
68 |   // TODO: replace it with Error(message, { cause }) when cause has broad support
69 |   if (formatted) withNoop(() => logger.error(new Error(formatted)))
                                                      ^
error: Error in plugin handler:
      at /myproject/node_modules/dd-trace/packages/dd-trace/src/log/writer.js:69:50
      at withNoop (/myproject/node_modules/dd-trace/packages/dd-trace/src/log/writer.js:25:1)
      at onError (/myproject/node_modules/dd-trace/packages/dd-trace/src/log/writer.js:82:7)
      at publish (node:diagnostics_channel:79:10)
      at error (/myproject/node_modules/dd-trace/packages/dd-trace/src/log/index.js:82:20)
      at wrappedHandler (/myproject/node_modules/dd-trace/packages/dd-trace/src/plugins/plugin.js:104:5)
      at /myproject/node_modules/dd-trace/packages/dd-trace/src/plugins/plugin.js:21:42
      at publish (node:diagnostics_channel:79:10)
      at /myproject/node_modules/dd-trace/packages/datadog-instrumentations/src/net.js:118:18
      at runInAsyncScope (node:async_hooks:128:18)

 9 | 
10 |   constructor (...args) {
11 |     super(...args)
12 | 
13 |     this.addTraceSub('connection', ({ socket }) => {
14 |       const span = this.activeSpan
                             ^
TypeError: undefined is not an object (evaluating 'this.activeSpan.addTags')
      at /myproject/node_modules/dd-trace/packages/datadog-plugin-net/src/tcp.js:14:25
      at wrappedHandler (/myproject/node_modules/dd-trace/packages/dd-trace/src/plugins/plugin.js:99:44)
      at /myproject/node_modules/dd-trace/packages/dd-trace/src/plugins/plugin.js:21:42
      at publish (node:diagnostics_channel:79:10)
      at /myproject/node_modules/dd-trace/packages/datadog-instrumentations/src/net.js:118:18
      at runInAsyncScope (node:async_hooks:128:18)
      at onceWrapper (node:events:164:21)
      at emit (node:events:56:48)
      at runInAsyncScope (node:async_hooks:128:18)
      at open (node:net:73:9)

Disabling plugin: undefined

I tried to debug a little, and noticed that the activeSpan that should be stored in an AsyncLocalStorage is lost between the start of a span and the end. This might be because of this issue on bun side: https://github.com/oven-sh/bun/issues/6393

Other than this issue, nearly no data is actually sent to the agent. My APM service does appear in the fleet automation page, linked to the correct agent handling it. But then I get a 404 error page when I try to open the service page.

Thanks!

[rburgst]

@na-ji how do I run the tracer in debug?

[na-ji]

@na-ji how do I run the tracer in debug?

You need to run your instrumented app with this env variable DD_TRACE_DEBUG=true:

https://docs.datadoghq.com/tracing/troubleshooting/tracer_debug_logs/#manual-debug-log-collection

[rburgst]

ok, I managed to get dd-trace to work (so so) in bun, however it messes with exceptions being logged, see https://github.com/rburgst/bun-dd-trace and https://github.com/oven-sh/bun/issues/15486, basically I get the following exception when remote fetch calls fail:

[07:12:33.795] ERROR (10977): error during upstream request {}
    err: {
      "type": "TypeError",
      "message": "|this| is not an object",
      "stack":
          TypeError: |this| is not an object
              at reject (native:1:11)
              at processTicksAndRejections (native:7:39)
    }

[zackradisic]

Noting here that if you use dd-trace/init with the runtimeMetrics option set to true, this will use the @datadog/native-metrics NAPI module which uses libuv and V8 functions which we currently do not support

You will see an error like dyld[89513]: missing symbol called (on macOS for example)

There is a list of the libuv / V8 C++ APIs which are supported here: https://github.com/oven-sh/bun/issues/4290

[seslly]

For anyone else who got here because of the missing symbol or segfault errors, to be very explicit on getting past that:

You need to disable profiling AND runtimeMetrics which are the specific code branches that causes errors. This can be configured through the tracer.init and/or through env vars DD_PROFILING_ENABLED=false and DD_RUNTIME_METRICS_ENABLED=false

tracer.init({
  logInjection: true,
  port: 8126,
  sampleRate: 0.5
  profiling: false,
  runtimeMetrics: false,
});