Validate that required functionality in Elasticsearch is available upon initial connection (#1015)

Author: kares

CHANGELOG.md

@@ -1,3 +1,6 @@
+## 11.0.2
+ - Validate that required functionality in Elasticsearch is available upon initial connection [#1015](https://github.com/logstash-plugins/logstash-output-elasticsearch/pull/1015)
+
 ## 11.0.1
  - Fix: DLQ regression shipped in 11.0.0 [#1012](https://github.com/logstash-plugins/logstash-output-elasticsearch/pull/1012)
  - [DOC] Fixed broken link in list item [#1011](https://github.com/logstash-plugins/logstash-output-elasticsearch/pull/1011)

lib/logstash/outputs/elasticsearch/license_checker.rb

@@ -11,7 +11,7 @@ def initialize(logger)
     # @param url [LogStash::Util::SafeURI] ES node URL
     # @return [Boolean] true if provided license is deemed appropriate
     def appropriate_license?(pool, url)
-      license = pool.get_license(url)
+      license = extract_license(pool.get_license(url))
       case license_status(license)
       when 'active'
         true
@@ -24,20 +24,26 @@ def appropriate_license?(pool, url)
       end
     end
 
+    NO_LICENSE = {}.freeze
+    private_constant :NO_LICENSE
+
+    def extract_license(license)
+      license.fetch("license", NO_LICENSE)
+    end
+
     def license_status(license)
-      license.fetch("license", {}).fetch("status", nil)
+      license.fetch("status", nil)
     end
 
     private
 
     def warn_no_license(url)
-      @logger.error("Connecting to an OSS distribution of Elasticsearch is no longer supported, " +
-                    "please upgrade to the default distribution of Elasticsearch", url: url.sanitized.to_s)
+      @logger.error("Could not connect to a compatible version of Elasticsearch", url: url.sanitized.to_s)
     end
 
     def warn_invalid_license(url, license)
-      @logger.warn("WARNING: Current Elasticsearch license is not active, " +
-                   "please check Elasticsearch's licensing information", url: url.sanitized.to_s, license: license)
+      @logger.warn("Elasticsearch license is not active, please check Elasticsearch’s licensing information",
+                   url: url.sanitized.to_s, license: license)
     end
 
   end

logstash-output-elasticsearch.gemspec

@@ -1,6 +1,6 @@
 Gem::Specification.new do |s|
   s.name            = 'logstash-output-elasticsearch'
-  s.version         = '11.0.1'
+  s.version         = '11.0.2'
 
   s.licenses        = ['apache-2.0']
   s.summary         = "Stores logs in Elasticsearch"