Enable use AWS profiles other than default (#1248)

* Use AWS_PROFILE with fallback to AWS_DEFAULT_PROFILE env variables
when reading ~/.aws/credentials file; use "default" when not set.

Signed-off-by: Nik Krumm <nkrumm@gmail.com>

* Add documentation.

Signed-off-by: Nik Krumm <nkrumm@gmail.com>

docs/awscloud.rst

@@ -38,6 +38,9 @@ Nextflow will use the AWS credentials defined in your environment, using the sta
     * ``AWS_SECRET_ACCESS_KEY``
     * ``AWS_DEFAULT_REGION``
 
+If ``AWS_ACCESS_KEY_ID`` and ``AWS_SECRET_ACCESS_KEY`` are not defined in the environment, Nextflow will attempt to 
+retrieve credentials from your ``~/.aws/credentials`` or ``~/.aws/config`` files. The ``default`` profile can be
+overridden via the environmental variable ``AWS_PROFILE`` (or ``AWS_DEFAULT_PROFILE``).
 
 Alternatively AWS credentials can be specified in the Nextflow configuration file.
 See :ref:`AWS configuration<config-aws>` for more details.

modules/nf-commons/src/main/nextflow/Global.groovy

@@ -101,8 +101,9 @@ class Global {
 
         for( Path it : files ) {
             final conf = new IniFile(it)
-            if( (a=conf.section('default').aws_access_key_id) && (b=conf.section('default').aws_secret_access_key) ) {
-                log.debug "Using AWS credential defined in `default` section in file: ${conf.file}"
+            final profile = env.get('AWS_PROFILE', env.get('AWS_DEFAULT_PROFILE', 'default'))
+            if( (a=conf.section(profile).aws_access_key_id) && (b=conf.section(profile).aws_secret_access_key) ) {
+                log.debug "Using AWS credential defined in `${profile}` section in file: ${conf.file}"
                 return [a,b]
             }
         }