updated .envrc-aws

.envrc-aws

@@ -1,10 +1,12 @@
+#!/usr/bin/env bash
+#  vim:ts=4:sts=4:sw=4:et
 #
 #  Author: Hari Sekhon
 #  Date: 2021-07-27 12:42:32 +0100 (Tue, 27 Jul 2021)
 #
 #  vim:ts=4:sts=4:sw=4:et
 #
-#  https://github.com/HariSekhon/bash-tools
+#  https://github.com/HariSekhon/DevOps-Bash-tools
 #
 #  License: see accompanying Hari Sekhon LICENSE file
 #
@@ -14,21 +16,39 @@
 #
 
 set -euo pipefail
-[ -n "${debug:-}" ] && set -x
-#srcdir="$(dirname "${bash_source[0]}")"
+[ -n "${DEBUG:-}" ] && set -x
+srcdir="$(dirname "${BASH_SOURCE[0]}")"
 
-# XXX: Edit
+# XXX: Edit - crucial to set to the right environment, the rest of the inferred settings below depend on this
 export AWS_PROFILE="default"
 
-# XXX: Edit
-export AWS_DEFAULT_REGION="eu-west-2"
+AWS_ACCOUNT="$(aws sts get-caller-identity --query Account --output text || aws configure get sso_account_id || :)"
+export AWS_ACCOUNT
+AWS_DEFAULT_REGION="$(aws configure get region || :)"  # use region configured in profile by default
+AWS_DEFAULT_REGION="${AWS_DEFAULT_REGION:-eu-west-2}"  # XXX: Edit default fallback region
+export AWS_DEFAULT_REGION
 export AWS_DEFAULT_OUTPUT=json
 
 # XXX: Edit
-export EKS_CONTEXT="MYCONTEXT"
+export EKS_CLUSTER="mycluster"
+# If EKS_CLUSTER isn't set and there is only one EKS cluster in this account and region, then use it - smart, but slower, prefer setting it explicitly for speed
+if [ -z "${EKS_CLUSTER:-}" ]; then
+    eks_clusters=()
+    while IFS='' read -r line; do
+        eks_clusters+=("$line")
+    done < <(aws eks list-clusters --output=json | jq -r '.clusters[]')
+    if [ "${#eks_clusters[@]}" -eq 1 ]; then
+        export EKS_CLUSTER="${eks_clusters[*]}"
+    fi
+fi
+
+if [ -n "${EKS_CLUSTER:-}" ]; then
+    # kubectl context is easily created by running adjacent aws_kube_creds.sh script first
+    export EKS_CONTEXT="arn:aws:eks:$AWS_DEFAULT_REGION:$AWS_ACCOUNT:cluster/$EKS_CLUSTER"
 
-# shellcheck disable=SC1090
-. "$srcdir/.envrc-kubernetes" "$EKS_CONTEXT"
+    # shellcheck disable=SC1090
+    . "$srcdir/.envrc-kubernetes" "$EKS_CONTEXT"
+fi
 
 # better to load this dynamically from credentials, using functions in .bash.d/aws.sh
 #export AWS_ACCESS_KEY_ID=...