From f5daf91e8d46687e40f8844d6cdf68f2fe85e8f6 Mon Sep 17 00:00:00 2001
From: Andris Reinman <andris@reinman.eu>
Date: Wed, 6 Mar 2024 11:54:32 +0200
Subject: [PATCH] fix(fetch): Allow to set the fetch batch size limit with a
 cli argument

---
 lib/consts.js  |  2 +-
 lib/mailbox.js | 10 +++++++---
 2 files changed, 8 insertions(+), 4 deletions(-)

diff --git a/lib/consts.js b/lib/consts.js
index 43fc6c89..1a535188 100644
--- a/lib/consts.js
+++ b/lib/consts.js
@@ -167,7 +167,7 @@ module.exports = {
     FETCH_RETRY_INTERVAL: 1000,
     FETCH_RETRY_EXPONENTIAL: 2,
     FETCH_RETRY_MAX: 60 * 1000,
-    MAX_FETCH_RANGE: Number((process.env.EENGINE_MAX_FETCH_RANGE || '').toString().trim()) || 1000,
+    DEFAULT_FETCH_BATCH_SIZE: 1000,
 
     generateWebhookTable() {
         let entries = [];
diff --git a/lib/mailbox.js b/lib/mailbox.js
index ee3b78c4..2e4a35d6 100644
--- a/lib/mailbox.js
+++ b/lib/mailbox.js
@@ -9,12 +9,14 @@ const {
     download,
     filterEmptyObjectValues,
     validUidValidity,
-    calculateFetchBackoff
+    calculateFetchBackoff,
+    readEnvValue
 } = require('./tools');
 const msgpack = require('msgpack5')();
 const he = require('he');
 const libmime = require('libmime');
 const settings = require('./settings');
+const config = require('wild-config');
 const { bounceDetect } = require('./bounce-detect');
 const { arfDetect } = require('./arf-detect');
 const appendList = require('./append-list');
@@ -38,9 +40,11 @@ const {
     REDIS_PREFIX,
     MAX_INLINE_ATTACHMENT_SIZE,
     MAX_ALLOWED_DOWNLOAD_SIZE,
-    MAX_FETCH_RANGE
+    DEFAULT_FETCH_BATCH_SIZE
 } = require('./consts');
 
+const FETCH_BATCH_SIZE = Number(readEnvValue('EENGINE_FETCH_BATCH_SIZE') || config.service.fetchBatchSize) || DEFAULT_FETCH_BATCH_SIZE;
+
 // Do not check for flag updates using full sync more often than this value
 const FULL_SYNC_DELAY = 30 * 60 * 1000;
 
@@ -54,7 +58,7 @@ function getFetchRange(totalMessages, lastRange) {
     if (startUid > totalMessages) {
         return false;
     }
-    let endMarker = startUid + MAX_FETCH_RANGE - 1;
+    let endMarker = startUid + FETCH_BATCH_SIZE - 1;
     if (endMarker >= totalMessages) {
         endMarker = '*';
     }