Bug/33659 pin generation queue messages are too large (#1244)

* [admin] add config.prepareCheckMessageBatchSize

* [admin] FIX: prepare check message size too large

Allow a configurable number of messages to be sent across to the prepare-check queue to work around the fact that
20 messages was too large.

* [admin] add logging

admin/config.js

@@ -37,6 +37,7 @@ module.exports = {
   OVERRIDE_AVAILABILITY_MIDDLEWARE: false,
   OverridePinExpiry: process.env.hasOwnProperty('OVERRIDE_PIN_EXPIRY') ? toBool(process.env.OVERRIDE_PIN_EXPIRY) : false,
   PORT: process.env.PORT || '3001',
+  prepareCheckMessageBatchSize: process.env.hasOwnProperty('PREPARE_CHECK_MESSAGE_BATCH_SIZE') ? parseInt(process.env.PREPARE_CHECK_MESSAGE_BATCH_SIZE, 10) : 5,
   PUPIL_APP_URL: process.env.PUPIL_APP_URL,
   PupilAppUseCompression: process.env.hasOwnProperty('PUPIL_APP_USE_COMPRESSION') ? toBool(process.env.PUPIL_APP_USE_COMPRESSION) : true,
   RESTART_MAX_ATTEMPTS: 2,

admin/services/check-start.service.js

@@ -150,9 +150,14 @@ checkStartService.prepareCheck2 = async function (
 
   // Send batch messages each containing the up to 20 prepare check messages.   This avoids hitting the max message size
   // for Azure Queues of 64Kb
-  const batches = R.splitEvery(20, prepareCheckQueueMessages)
+  logger.info(`check start service: prepare check batch size is ${config.prepareCheckMessageBatchSize}`)
+  const batches = R.splitEvery(config.prepareCheckMessageBatchSize, prepareCheckQueueMessages)
+  let batchCount = 1
+  let totalBatches = batches.length
   for (let batch of batches) {
+    logger.info(`check start service: sending batch ${batchCount} of ${totalBatches} for school ${schoolId}`)
     await azureQueueService.addMessageAsync(prepareCheckQueueName, { version: 2, messages: batch })
+    batchCount += 1
   }
 
   // Store the `config` section from the preparedCheckMessages into the DB