Extend storage of Testrun Messages and truncate long output

app/models/testrun_message.rb

@@ -11,14 +11,14 @@ class TestrunMessage < ApplicationRecord
     turtlebatch: 4,
     render: 5,
     exit: 6,
-    timeout: 7,
-    out_of_memory: 8,
-    status: 9,
-    hint: 10,
-    client_kill: 11,
-    exception: 12,
-    result: 13,
-    canvasevent: 14,
+    status: 7,
+    hint: 8,
+    client_kill: 9,
+    exception: 10,
+    result: 11,
+    canvasevent: 12,
+    timeout: 13, # TODO: Shouldn't be in the data, this is a status and can be removed after the migration finished
+    out_of_memory: 14, # TODO: Shouldn't be in the data, this is a status and can be removed after the migration finished
   }, _default: :write, _prefix: true
 
   enum stream: {
@@ -34,21 +34,52 @@ class TestrunMessage < ApplicationRecord
   validate :either_data_or_log
 
   def self.create_for(testrun, messages)
+    # We don't want to store anything if the testrun passed
+    return if testrun.passed?
+
     messages.map! do |message|
       # We create a new hash and move all known keys
       result = {}
       result[:testrun] = testrun
-      result[:log] = message.delete(:log) || (message.delete(:data) if message[:cmd] == :write)
+      result[:log] = (message.delete(:log) || message.delete(:data)) if message[:cmd] == :write || message.key?(:log)
       result[:timestamp] = message.delete :timestamp
-      result[:stream] = message.delete :stream
+      result[:stream] = message.delete :stream if message.key?(:stream)
       result[:cmd] = message.delete :cmd
       # The remaining keys will be stored in the `data` column
-      result[:data] = message.presence
+      result[:data] = message.presence if message.present?
       result
     end
 
+    # Before storing all messages, we truncate some to save storage
+    filtered_messages = filter_messages_by_size testrun, messages
+
     # An array with hashes is passed, all are stored
-    TestrunMessage.create!(messages)
+    TestrunMessage.create!(filtered_messages)
+  end
+
+  def self.filter_messages_by_size(testrun, messages)
+    limits = if testrun.submission.cause == 'requestComments'
+               {data: {limit: 25, size: 0}, log: {limit: 5000, size: 0}}
+             else
+               {data: {limit: 10, size: 0}, log: {limit: 500, size: 0}}
+             end
+
+    filtered_messages = messages.map do |message|
+      if message.key?(:log) && limits[:log][:size] < limits[:log][:limit]
+        message[:log] = message[:log][0, limits[:log][:limit] - limits[:log][:size]]
+        limits[:log][:size] += message[:log].size
+      elsif message[:data] && limits[:data][:size] < limits[:data][:limit]
+        limits[:data][:size] += 1
+      elsif !message.key?(:log) && limits[:data][:size] < limits[:data][:limit]
+        # Accept short TestrunMessages (e.g. just transporting a status information)
+        # without increasing the `limits[:data][:limit]` before the limit is reached
+      else
+        # Clear all remaining messages
+        message = nil
+      end
+      message
+    end
+    filtered_messages.select(&:present?)
   end
 
   def either_data_or_log