Stop raising on unsupported log_level

judoscale-ruby/lib/judoscale/config.rb

@@ -59,6 +59,10 @@ def as_json
       end
     end
 
+    BLANK_REGEXP = /\A[[:space:]]*\z/.freeze
+
+    private_constant :BLANK_REGEXP
+
     include Singleton
 
     @adapter_configs = []
@@ -110,7 +114,7 @@ def reset
     end
 
     def log_level=(new_level)
-      @log_level = new_level ? ::Logger::Severity.const_get(new_level.to_s.upcase) : nil
+      @log_level = blank_log_level?(new_level) ? nil : get_severity_log_level(new_level)
     end
 
     def as_json
@@ -127,5 +131,23 @@ def as_json
     def ignore_large_requests?
       @max_request_size_bytes
     end
+
+    private
+
+    def blank_log_level?(log_level)
+      log_level.nil? || log_level.match?(BLANK_REGEXP)
+    end
+
+    def get_severity_log_level(log_level)
+      upcased_log_level = log_level.to_s.upcase
+
+      if ::Logger::Severity.const_defined?(upcased_log_level)
+        ::Logger::Severity.const_get(upcased_log_level)
+      else
+        logger.warn "Invalid log_level detected: #{log_level}"
+
+        nil
+      end
+    end
   end
 end

judoscale-ruby/test/config_test.rb

@@ -89,6 +89,19 @@ module Judoscale
       end
     end
 
+    it 'gracefully handles invalid JUDOSCALE_LOG_LEVEL values' do
+      env = {
+        "JUDOSCALE_LOG_LEVEL" => "not_a_real_log_level"
+      }
+
+      use_env env do
+        config = Config.instance
+        _(config.log_level).must_be_nil
+      end
+
+      _(log_string).must_include "Invalid log_level detected: not_a_real_log_level"
+    end
+
     it "supports legacy ENV var configs" do
       env = {
         "RAILS_AUTOSCALE_MAX_QUEUES" => "42",
@@ -133,6 +146,28 @@ module Judoscale
       _(enabled_adapter_configs).must_be :empty?
     end
 
+    it 'gracefully handles invalid log_level values and logs a warning' do
+      Judoscale.configure do |config|
+        config.log_level = :not_a_real_log_level
+      end
+
+      config = Config.instance
+      _(config.log_level).must_be_nil
+
+      _(log_string).must_include "Invalid log_level detected: not_a_real_log_level"
+    end
+
+    it 'gracefully handles blank log_level values' do
+      Judoscale.configure do |config|
+        config.log_level = " "
+      end
+
+      config = Config.instance
+      _(config.log_level).must_be_nil
+
+      _(log_string).wont_include "Invalid log_level detected"
+    end
+
     it "dumps the configuration options as json" do
       _(Config.instance.as_json).must_equal({
         log_level: nil,