ci: Add test for Logspout extension

.github/workflows/scripts/run-tests-logspout.sh

@@ -0,0 +1,52 @@
+#!/usr/bin/env bash
+
+set -eu
+set -o pipefail
+
+
+source "$(dirname ${BASH_SOURCE[0]})/lib/testing.sh"
+
+
+cid_es="$(container_id elasticsearch)"
+cid_ls="$(container_id logspout)"
+
+ip_es="$(service_ip elasticsearch)"
+ip_ls="$(service_ip logspout)"
+
+log 'Waiting for readiness of Elasticsearch'
+poll_ready "$cid_es" "http://${ip_es}:9200/" -u 'elastic:testpasswd'
+
+log 'Waiting for readiness of Logspout'
+poll_ready "$cid_ls" "http://${ip_ls}/health"
+
+# When Logspout starts, it prints the following log line:
+#   2021/01/07 16:14:52 # logspout v3.2.13-custom by gliderlabs
+#
+# which we expect to find by querying:
+#   docker.image:"docker-elk_logspout" AND message:"logspout gliderlabs"~3
+#
+log 'Searching a log entry forwarded by Logspout'
+
+declare response
+declare -i count
+
+# retry for max 60s (30*2s)
+for _ in $(seq 1 30); do
+	response="$(curl "http://${ip_es}:9200/_count?q=docker.image:%22docker-elk_logspout%22%20AND%20message:%22logspout%20gliderlabs%22~3&pretty" -s -u elastic:testpasswd)"
+	count="$(jq -rn --argjson data "${response}" '$data.count')"
+	if [[ $count -gt 0 ]]; then
+		break
+	fi
+
+	echo -n 'x' >&2
+	sleep 2
+done
+echo -e '\n' >&2
+
+echo "$response"
+# Logspout may restart if Logstash isn't ready yet, so we tolerate multiple
+# results
+if [[ $count -lt 1 ]]; then
+	echo "Expected at least 1 document, got ${count}"
+	exit 1
+fi