Slow Uploading to S3 when using IAM Role

[edwardjlam]

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Issue Details

If filing a bug report, please include a list of steps that describe how to
reproduce the bug you are experiencing. Include your config being passed to the S3Plugin.

Versions used:
os: ubuntu 16.04
node: 8.11.4
npm: 6.4.0
webpack: 3.12.0
s3-webpack-plugin: 1.0.0-rc.0

Issue:
When uploading to s3 the process is slow when credentials are pulled through the IAM Role meta-data that is associated with the ec2 instance.

Steps to reproduce:
Run webpack with the s3-webpack-plugin and attempt to upload to s3 with out providing credentials in either the config file or as an environment variable.

Expected result: uploading of all assets should take the same time when using IAM role or hard coding credentials

Actual results: uploading with the IAM role takes about 4 times as long as hardcoding the Credentials.

[MikaAK]

I have no idea why this would be, any further investigation is welcome.

[gracefullee]

@eddjlam upgrade your webpack-s3-plugin to 1.0.2, that did the trick for us.

[edwardjlam]

@gracefullee I'm unable to update to 1.0.2 as it has a dependency of webpack4. I've worked around this issue by getting the AWS credentials from the meta data endpoint and placing them in environment variables. the root cause seems to be the AWS STS endpoint

[MikaAK]

Please make a new issue with more info @lasantha57