Minor fixes to agent installation (#24)

*Issue #, if available:*
N/A
*Description of changes:*
* Updated both the install script and the systemd service to use the
executable name that is built (aws_secretsmanager_agent) instead of the
previous aws-secrets-manager-agent.
* Due to install script running as root, files in bin directory are not
owned by the AGENTUSER. This is necessary for systemd run processes.
Added additional chown to recursively set the owner to AGENTUSER within
AGENTDIR.
* Added minor change to not fail if the AGENTUSER already exists.

By submitting this pull request, I confirm that my contribution is made
under the terms of the Apache 2.0 license.

aws_secretsmanager_agent/configuration/awssmastartup.service

@@ -13,7 +13,7 @@ Environment="AWS_TOKEN=file:///var/run/awssmatoken"
 Type=exec
 Restart=always
 TimeoutSec=1min
-ExecStart=/opt/aws/secretsmanageragent/bin/aws-secrets-manager-agent
+ExecStart=/opt/aws/secretsmanageragent/bin/aws_secretsmanager_agent
 
 [Install]
 WantedBy=multi-user.target

aws_secretsmanager_agent/configuration/install

@@ -3,7 +3,7 @@
 PATH=/bin:/usr/bin:/sbin:/usr/sbin # Use a safe path
 
 AGENTDIR=/opt/aws/secretsmanageragent
-AGENTBIN=aws-secrets-manager-agent
+AGENTBIN=aws_secretsmanager_agent
 TOKENGROUP=awssmatokenreader
 AGENTUSER=awssmauser
 TOKENSCRIPT=awssmaseedtoken
@@ -27,11 +27,12 @@ if [ ! -r ${AGENTBIN} ]; then
 fi
 
 groupadd -f ${TOKENGROUP}
-useradd -r -m -g ${TOKENGROUP} -d ${AGENTDIR} ${AGENTUSER}
+useradd -r -m -g ${TOKENGROUP} -d ${AGENTDIR} ${AGENTUSER} || true
 chmod 755 ${AGENTDIR}
 
 install -D -T -m 755 ${AGENTBIN} ${AGENTDIR}/bin/${AGENTBIN}
 install -D -T -m 755 ${TOKENSCRIPT} ${AGENTDIR}/bin/${TOKENSCRIPT}
+chown -R ${AGENTUSER} ${AGENTDIR}
 install -T -m 755 ${TOKENSCRIPT}.service ${SYSTEMDFILES}/${TOKENSCRIPT}.service 
 install -T -m 755 ${AGENTSCRIPT}.service ${SYSTEMDFILES}/${AGENTSCRIPT}.service