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bitter-ability-32190

12/28/2022, 3:12 PM
I'm getting a cryptic error on the rust side (with some new changes), I think it's coming from trying to read a file on disk with perms 
600
, and my user. When running with the daemon I see the error, without I see a different error (later in the code). What perms/user does the daemon run as?
e

enough-analyst-54434

12/28/2022, 3:31 PM
ps -ef | grep pantsd
or your favorite variant to see the user.
b

bitter-ability-32190

12/28/2022, 3:31 PM
Running as my user 🤔
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$ ps -ef | grep pantsd
josh       31864   18485  0 09:31 pts/0    00:00:00 grep --color=auto pantsd
The file in question:
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$ ls -l ~/.aws/credentials 
-rw------- 1 josh josh 116 Nov 15 08:56 /home/josh/.aws/credentials
e

enough-analyst-54434

12/28/2022, 3:33 PM
The ps has 0 hits though, that's just a hit for your grep
b

bitter-ability-32190

12/28/2022, 3:33 PM
I don't think so, see 
--color=auto
? Makes me think it matched the daemon
e

enough-analyst-54434

12/28/2022, 3:34 PM
Maybe widen the scope to python or just read the pid file to find the pid.
b

bitter-ability-32190

12/28/2022, 3:34 PM
oh thats the arg to grep, lol
e

enough-analyst-54434

12/28/2022, 3:35 PM
Then muck about in /proc/<pid>/... - 18 ways
b

bitter-ability-32190

12/28/2022, 3:48 PM
better:
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josh       36453   12042  4 09:46 ?        00:00:07 pantsd [/home/josh/work/pants]
still me
e

enough-analyst-54434

12/28/2022, 4:01 PM
Depending what / where the error is, this could be a good thing. If a X00 file makes it in the lmdb, you've likely just been owned, by yourself. Anything in lmdb can be just as easily remoted and the visible to everyone hooked up to your remoting.
b

bitter-ability-32190

12/28/2022, 4:02 PM
This is a file being read directly on the rust side. For transparency I'm looking into maybe supporting s3 as a URI, and that requires AWS credentials
e

enough-analyst-54434

12/28/2022, 4:03 PM
Ok, watch that lmdb!
b

bitter-ability-32190

12/28/2022, 4:03 PM
So I'm leveraging a library that reads the correct config(s) directly. With the daemon I get some vague error (I blame the library) without the daemon I have no affliction
e

enough-analyst-54434

12/28/2022, 4:04 PM
Ok, I'll let you have the pleasure of finding things out there. Just wanted to raise that dire prospect in case you were drifting there. The number of times Twitter leaked credentials to OSS was embarrassing, left mental scars.
b

bitter-ability-32190

12/28/2022, 4:06 PM
Well it's still a slight cry for help. I'm admittedly out of my element as I've only used Unix for a year now 😛 If the daemon is running as 
josh
, should it not be able to read a file whose owner is 
josh
? Perhaps I'll test this with an empty file in my source tree with those perms
e

enough-analyst-54434

12/28/2022, 4:30 PM
Please provide all details if you want help. What's the backtrace / error and where is the code. Same as I'd ask of a general question.
b

bitter-ability-32190

12/28/2022, 4:42 PM
Anyway to get a traceback from native code?
e

enough-analyst-54434

12/28/2022, 4:49 PM
RUST_BACKTRACE=1 for rust controlled panics. If it's segfaulty, you need to attach gdb to the process and then get thread backtraces from within the gdb session.
b

bitter-ability-32190

12/28/2022, 5:07 PM
Something has gone very sideways...
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11:06:50.38 [INFO] Filesystem changed during run: retrying `ExportCodegen` in 500ms...
11:06:53.89 [INFO] Filesystem changed during run: retrying `ExportCodegen` in 500ms...
11:06:57.41 [INFO] Filesystem changed during run: retrying `ExportCodegen` in 500ms...
11:07:00.92 [INFO] Filesystem changed during run: retrying `ExportCodegen` in 500ms...
11:07:04.44 [INFO] Filesystem changed during run: retrying `ExportCodegen` in 500ms...
11:07:07.95 [INFO] Filesystem changed during run: retrying `ExportCodegen` in 500ms...
Turning on 
RUST_BACKTRACE
seems to kick the filewatcher continusously
Oddly the log in 
.pants.d/run-tracker
shows:
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11:15:25.14 [31m[ERROR][0m panic at 'called `Result::unwrap()` on an `Err` value: CredentialsNotLoaded(CredentialsNotLoaded { source: "no providers in chain provided credentials" })', src/downloads.rs:119
11:15:25.14 [31m[ERROR][0m Please set RUST_BACKTRACE=1, re-run, and then file a bug at <https://github.com/pantsbuild/pants/issues>.
This is with:
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$ RUST_BACKTRACE=1 ./pants export-codegen //:dumpit
e

enough-analyst-54434

12/28/2022, 5:18 PM
So you have a panic identified now. Presumably you're off and running.
b

bitter-ability-32190

12/28/2022, 5:18 PM
No, since it distinctly isn't logging the backtrace
e

enough-analyst-54434

12/28/2022, 5:19 PM
Well you have file and line.
b

bitter-ability-32190

12/28/2022, 5:19 PM
I knew that previously, it's in the code I'm authoring. That line just calls into a 3rdparty library
e

enough-analyst-54434

12/28/2022, 5:20 PM
Ok. Well, get creative! You need pantsd to launch with that env var, make sure it is getting launched with that.
Catch the panic yourself. I've done that to debug hard to debug. The rust code for that is tricky but we'll documented.
Hopefully you don't need to do that, but it's an option.
b

bitter-ability-32190

12/28/2022, 5:22 PM
I might just have to go manually start following the 3rdparty's source code 😕
Although I think I have a new theorey. The code likely uses 
~
as a path and the home for the daemon is not my home
Yup thats it. It's trying to read 
~/...
and 
HOME
isnt set on the daemon
So, now we understand why it's failing, time to think about fixes. Should the daemon have 
HOME
set? Seems like this certainly would match the behavior of 
--no-pantsd
https://github.com/pantsbuild/pants/pull/11641
Finally, we empty the environment for 
pantsd
runs to enforce explicit usage of `CompleteEnvironment`/`Environment`.
Yeah that's not a bad goal. This particular use comes from the intrinsic though 🤔
It looks like the env vars I might need here are 
HOME
and any 
AWS_*
env vars...
e

enough-analyst-54434

12/28/2022, 7:57 PM
Can the intrinsic not take (portions of) the environment as an explicit parameter?
Basically, just like rules do for Processes
b

bitter-ability-32190

12/28/2022, 7:58 PM
Yeah, I was trying to tease that out from the existing code. It might, but so far I haven't cracked it
MMmm thats a good trail of crumbs to follow
e

enough-analyst-54434

12/28/2022, 7:59 PM
I've got to say I find this chat-whiteboarding befuddling, but I'm glad it works for you.
b

bitter-ability-32190

12/28/2022, 8:45 PM
So looks like normal rules use 
EnvironmentVarsRequest
which I don't think the intrinsics can use. I would assume I could use 
CompleteEnvironmentVars
as an input, but wiring that up gives a GraphError (it also means each download node would depend on all env vars. Not fatal but maybe unfortunate)
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intrinsics.insert(
      Intrinsic {
        product: types.directory_digest,
        inputs: vec![
          DependencyKey::new(types.download_file),
          DependencyKey::new(types.complete_env_vars),
        ],
      },
      Box::new(download_file_to_digest),
    );
# Keep in sync with <http://intrinsics.rs|intrinsics.rs>
oh booooo
I just happened to stumble on that at random
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