slackUploadFile is hanging

[eyepiz-nflx]

Jenkins and plugins versions report

Environment

Jenkins: 2.504.2
OS: Linux - 6.8.0-1029-aws
Java: 17.0.14.0.101 - Azul Systems, Inc. (OpenJDK 64-Bit Server VM)
---
Parameterized-Remote-Trigger:3.2.1
analysis-model-api:13.2.0
ansicolor:1.0.6
ant:497.v94e7d9fffa_b_9
antisamy-markup-formatter:173.v680e3a_b_69ff3
apache-httpcomponents-client-4-api:4.5.14-269.vfa_2321039a_83
apache-httpcomponents-client-5-api:5.5-150.veb_76e719855b_
asm-api:9.8-135.vb_2239d08ee90
authentication-tokens:1.131.v7199556c3004
aws-java-sdk-ec2:1.12.780-480.v4a_0819121a_9e
aws-java-sdk-minimal:1.12.780-480.v4a_0819121a_9e
aws-java-sdk-sns:1.12.780-480.v4a_0819121a_9e
aws-java-sdk-sqs:1.12.780-480.v4a_0819121a_9e
blesk:1.0
bootstrap4-api:4.6.0-3
bootstrap5-api:5.3.5-1
bouncycastle-api:2.30.1.80-261.v00c0e2618ec3
branch-api:2.1217.v43d8b_b_d8b_2c7
build-blocker-plugin:166.vc82fc20b_a_ed6
build-keeper-plugin:19.va_df8a_2c65123
build-monitor-plugin:1.14-985.v7b_f37b_3d0b_f5
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build-pipeline-plugin:1.5.8
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buildtriggerbadge:251.vdf6ef853f3f5
built-on-column:1.5
caffeine-api:3.2.0-166.v72a_6d74b_870f
cctray-xml:118.vef9f6f9c4122
checks-api:370.vb_61a_c57328f3
claim:599.v95c2f92e1c88
cloudbees-bitbucket-branch-source:809.vc1d904b_30426
cloudbees-disk-usage-simple:241.v0ea_d9a_a_96ee8
cloudbees-folder:6.1023.v4fcb_72152519
cobertura:1.17
code-coverage-api:4.99.0
command-launcher:123.v37cfdc92ef67
commons-compress-api:1.27.1-3
commons-lang3-api:3.17.0-87.v5cf526e63b_8b_
commons-text-api:1.13.1-176.v74d88f22034b_
conditional-buildstep:1.5.0
config-file-provider:988.v0461fcc2b_9d1
copyartifact:770.va_6c69e063442
coverage:2.6.0
credentials:1415.v831096eb_5534
credentials-binding:687.v619cb_15e923f
dashboard-view:2.432.va_712ce35862d
data-tables-api:2.2.2-1
description-setter:264.v1957f215dcd5
display-url-api:2.209.v582ed814ff2f
docker-commons:457.v0f62a_94f11a_3
docker-workflow:1.23
durable-task:587.v84b_877235b_45
dynamic-axis:1.0.3
ec2-ephemeral:1.0
echarts-api:5.6.0-4
eddsa-api:0.3.0.1-19.vc432d923e5ee
email-ext:1876.v28d8d38315b_d
embeddable-build-status:548.v5653c6e28c41
envinject:2.926.v69c9b_3896a_96
envinject-api:1.235.va_14c74f8f487
environment-script:1.2.3
extended-choice-parameter:0.76
extended-read-permission:3.2
file-parameters:367.vc2cc39fb_b_593
flexible-publish:0.16.1
font-awesome-api:6.7.2-1
forensics-api:3.1.0
fstrigger:1.02
git:5.7.0
git-client:6.1.3
git-parameter:439.vb_0e46ca_14534
git-server:1.11
github:1.43.0
github-api:1.321-488.v9b_c0da_9533f8
github-branch-source:1822.v9eec8e5e69e3
golang:1.1
gradle:2.15
groovy:497.v7b_061a_a_de65d
gson-api:2.13.1-139.v4569c2ef303f
handlebars:3.0.8
handy-uri-templates-2-api:2.1.8-22.v77d5b_75e6953
hidden-parameter:237.v4b_df26c7a_f0e
htmlpublisher:425
http_request:1.11
instance-identity:203.v15e81a_1b_7a_38
ionicons-api:88.va_4187cb_eddf1
ivy:2.4
jackson2-api:2.18.3-402.v74c4eb_f122b_2
jacoco:3.3.7
jakarta-activation-api:2.1.3-2
jakarta-mail-api:2.1.3-2
javadoc:327.vdfe586651ee0
javax-activation-api:1.2.0-8
javax-mail-api:1.6.2-11
jaxb:2.3.9-133.vb_ec76a_73f706
jdk-tool:83.v417146707a_3d
jenkins-multijob-plugin:662.vd2e0001f6b_b_d
jira:3.7.1
jjwt-api:0.11.5-120.v0268cf544b_89
jnr-posix-api:3.1.7-1
job-dsl:1.92
job-import-plugin:122.v35289550f1e6
jobConfigHistory:1305.vf20a_356586b_8
joda-time-api:2.14.0-127.v7d9da_295a_d51
jquery:1.12.4-3
jquery-detached:1.2.1
jquery3-api:3.7.1-3
jsch:0.2.16-95.v3eecb_55fa_b_78
json-api:20250517-153.vc8a_a_d87c0ce3
json-path-api:2.9.0-148.v22a_7ffe323ce
jsoup:1.20.1-46.ve5f1416988c2
junit:1335.v6b_a_a_e18534e1
label-linked-jobs:5.0.1
ldap:780.vcb_33c9a_e4332
lockable-resources:2.15
log-parser:2.2
mailer:489.vd4b_25144138f
mapdb-api:1.0.9.0
matrix-auth:3.2.6
matrix-project:849.v0cd64ed7e531
maven-plugin:3.26
metrics:4.2.32-476.v5042e1c1edd7
mina-sshd-api-common:2.15.0-161.vb_200831a_c15b_
mina-sshd-api-core:2.15.0-161.vb_200831a_c15b_
modernstatus:1.3
momentjs:1.1.1
monitoring:2.5.0
multibranch-scan-webhook-trigger:1.0.9
multiple-scms:0.8
naginator:1.504.vfc3736332f16
nested-view:239.vb_8c100b_46b_a_8
next-build-number:66.v4b_4762172d53
nflx-agent-management:1.0
nflx-agent-management-api:1.0
nflx-analytics:1.0
nflx-build-status-api:1.0
nflx-gandalf-authz:1.0
nflx-graceful-shutdown:1.0
nflx-initializer:1.0
nflx-job-management:1.0
nflx-managed-delivery:1.0
nflx-markperm:1.0
nflx-meechum-realm:1.1.0.0.0
nflx-metrics:1.0
nflx-metrics-api:1.0
nflx-parameters:1.0
nflx-queue-management:1.0
nflx-rocket-ci:1.0
nflx-rocket-ci-api:e9fbebaf
nflx-stash-notifier:1.0
nflx-webservice-api:1.0
nodejs:1.4.3
nodelabelparameter:759.vb_b_e95db_f3251
nodenamecolumn:1.2
nunit:571.v30a_1e3f86709
okhttp-api:4.11.0-189.v976fa_d3379d6
oneshot-agent:1.0
oss-symbols-api:324.v432cce4172ca_
p4:1.14.4
pam-auth:1.12
parameterized-scheduler:285.ve611986d4c48
parameterized-trigger:859.vb_e3907a_07a_16
people-view:1.2
performance:3.20
permissive-script-security:0.7
pipeline-as-yaml:270.vc348a_45d9214
pipeline-build-step:567.vea_ce550ece97
pipeline-graph-analysis:241.vc3d48fb_b_2582
pipeline-graph-view:551.vde72dc246b_c4
pipeline-groovy-lib:752.vdddedf804e72
pipeline-input-step:527.vd61b_1d3c5078
pipeline-milestone-step:138.v78ca_76831a_43
pipeline-model-api:2.2255.v56a_15e805f12
pipeline-model-definition:2.2255.v56a_15e805f12
pipeline-model-extensions:2.2255.v56a_15e805f12
pipeline-rest-api:2.38
pipeline-stage-step:322.vecffa_99f371c
pipeline-stage-tags-metadata:2.2255.v56a_15e805f12
pipeline-stage-view:2.38
pipeline-utility-steps:2.19.0
plain-credentials:195.vb_906e9073dee
plugin-usage-plugin:4.10
plugin-util-api:6.1.0
popper-api:1.16.1-2
popper2-api:2.11.6-2
postbuild-task:1.9
postbuildscript:3.4.1-695.vf6b_0b_8053979
preSCMbuildstep:0.3
prism-api:1.30.0-1
promoted-builds:992.va_00888f21b_74
rebuild:338.va_0a_b_50e29397
remote-file:1.14
resource-disposer:0.25
restricted-node-label:1.0
run-condition:243.v3c3f94e46a_8b_
scm-api:704.v3ce5c542825a_
script-security:1373.vb_b_4a_a_c26fa_00
sectioned-view:1.30
simple-smooth:1.0
simple-theme-plugin:211.v5424a_5510e47
slack:761.v2a_8770f0d169
snakeyaml-api:2.3-125.v4d77857a_b_402
ssh-agent:386.v36cc0c7582f0
ssh-credentials:355.v9b_e5b_cde5003
ssh-slaves:3.1031.v72c6b_883b_869
sshd:3.353.v2b_d33c46e970
stashNotifier:1.516.v6d49910f22a_5
structs:350.v3b_30f09f2363
swarm:3.28
takeout:1.0
testng-plugin:940.vc244edffc2ec
text-finder:1.10
throttle-concurrents:2.8
timestamper:1.29
titus:1.0
token-macro:444.v52de7e9c573d
trilead-api:2.209.v0e69b_c43c245
unique-id:2.117.v7a_81333a_584b_
uno-choice:2.8.8
variant:70.va_d9f17f859e0
versioncolumn:320.v6b_b_814ca_01f7
versionnumber:1.9
view-job-filters:1.26
warnings-ng:12.6.0
workflow-aggregator:608.v67378e9d3db_1
workflow-api:1373.v7b_813f10efa_b_
workflow-basic-steps:1079.vce64b_a_929c5a_
workflow-cps:4106.v7a_8a_8176d450
workflow-cps-global-lib:581.ve633085a_8a_87
workflow-durable-task-step:1405.v1fcd4a_d00096
workflow-job:1532.va_9a_d244074a_3
workflow-multibranch:806.vb_b_688f609ee9
workflow-scm-step:437.v05a_f66b_e5ef8
workflow-step-api:700.v6e45cb_a_5a_a_21
workflow-support:968.v8f17397e87b_8
ws-cleanup:0.48
xtrigger-api:1.2
xvfb:1.2

What Operating System are you using (both controller, and any agents involved in the problem)?

Controller: Ubuntu 22.04.5 LTS (jammy): 6.8.0-1029-aws x86_64 GNU/Linux
Agent: Ubuntu 22.04.5 LTS (jammy): 6.8.0-1030-aws x86_64 GNU/Linux

Reproduction steps

1. Create a pipeline

3. Go to Configure -> Pipeline

3. Select Pipeline script and add this code to the Script section:

def test(String channel, String comment) {
    echo "begin $comment - '$channel'"
    
    def slackUploadFile = slackUploadFile filePath: "*.txt", channel: "$channel"
    // ^ this hangs
    
    echo "end $comment - '$channel'"
}
node {
    sh "echo testing > blah.txt"

    // make sure to add the Jenkins app to the channel below
    test "your-slack-channel", "Testing slackUploadFile"
}

Be sure to update "your-slack-channel" to an actual Slack channel and add the Jenkins Slack app to that channel

4. Go back to the dashboard and click Build Now

Expected Results

The blah.txt file should be uploaded to the Slack channel that you specified. It would look something like this:

Actual Results

The job just hangs on the slackUploadFile step and the file is never uploaded. Navigate to the build's Console Output to see it hanging.

Anything else?

No response

Are you interested in contributing a fix?

No response

[timja]

Do you have a firewall of some kind in the way?

Potentially its blocking the file upload?

[eyepiz-nflx]

We don't have a firewall, our egress is unrestricted.

[timja]

Is there anything in the system log?

Otherwise you could enable more logging with a log recorder for org.apache.hc.client5.http
see also: https://github.com/jenkinsci/slack-plugin#enable-additional-logging

[aishchenko-readdle]

We also encountered an issue with file uploads.
It seems that the latest version 3.x of the Jenkins Slack Plugin has broken the file upload functionality.
We temporarily resolved the issue by downgrading the plugin to the previous version, 2.49.

No changes were made to the setup.

[timja]

Which version? the latest is this: https://github.com/jenkinsci/slack-plugin/releases/tag/761.v2a_8770f0d169

[vtkachuk-readdle]

Which version? the latest is this: https://github.com/jenkinsci/slack-plugin/releases/tag/761.v2a_8770f0d169

Yes, exactly 761.v2a_8770f0d169. We use the plugin not in a pipe, but via web Jenkins job config:

No errors in the log, no file mentions as well. Here OnSuccessNotification snippet:
Posting: to localization on company: {"attachments":[{"fallback":"PE Mac Code Localizable Strings Changes Canary - #47127 Success after 2.9 sec (<https://cloud-rd2-ci.od.company.com/job/PE%20Mac%20Code%20Localizable%20Strings%20Changes%20Canary/47127/display/redirect|Open>)\nHello, localization robot speaking :robot_face:\nProgrammer(s) have just changed some localizable strings in 'PEM Localization'.\n@translators please find the list of changes in the attached file below :arrow_down:","color":"good","fields":[{"short":false,"value":"PE Mac Code Localizable Strings Changes Canary - #47127 Success after 2.9 sec (<https://cloud-rd2-ci.od.company.com/job/PE%20Mac%20Code%20Localizable%20Strings%20Changes%20Canary/47127/display/redirect|Open>)\nHello, localization robot speaking :robot_face:\nProgrammer(s) have just changed some localizable strings in 'PEM Localization'.\n@translators please find the list of changes in the attached file below :arrow_down:"}],"mrkdwn_in":["pretext","text","fields"]}],"link_names":"1","unfurl_links":"true","unfurl_media":"true","channel":"localization","as_user":"true"}

[timja]

This is a different issue then, please create a new one.

Including which version you upgraded from and to.