From d80d1e24e9b1a278f7e94d894dfe6c0c4c80cd43 Mon Sep 17 00:00:00 2001
From: Klaus K Wilting <Klaus.K.Wilting@deutschebahn.com>
Date: Tue, 18 Sep 2018 22:58:02 +0200
Subject: [PATCH] ota.cpp: added a retry loop for write-to-flash

---
 platformio.ini      |  2 +-
 src/ota.cpp         | 36 +++++++++++++++++++++++++-----------
 src/paxcounter.conf |  1 +
 3 files changed, 27 insertions(+), 12 deletions(-)

diff --git a/platformio.ini b/platformio.ini
index 5ca50241..7cf58877 100644
--- a/platformio.ini
+++ b/platformio.ini
@@ -26,7 +26,7 @@ description = Paxcounter is a proof-of-concept ESP32 device for metering passeng
 
 [common]
 ; for release_version use max.10 chars total, use any decimal format like "a.b.c"
-release_version = 1.4.33
+release_version = 1.4.34
 ; DEBUG LEVEL: For production run set to 0, otherwise device will leak RAM while running!
 ; 0=None, 1=Error, 2=Warn, 3=Info, 4=Debug, 5=Verbose
 debug_level = 0
diff --git a/src/ota.cpp b/src/ota.cpp
index 5d94bbed..34136f85 100644
--- a/src/ota.cpp
+++ b/src/ota.cpp
@@ -112,7 +112,7 @@ void processOTAUpdate(const String &version) {
       }
     }
 
-    // ESP_LOGI(TAG, "Requesting: " + firmwarePath);
+    ESP_LOGI(TAG, "Requesting %s", firmwarePath);
 
     client.print(String("GET ") + firmwarePath + " HTTP/1.1\r\n");
     client.print(String("Host: ") + currentHost + "\r\n");
@@ -185,20 +185,33 @@ void processOTAUpdate(const String &version) {
 
   // check whether we have everything for OTA update
   if (contentLength && isValidContentType) {
-    if (Update.begin(contentLength)) {
-      ESP_LOGI(TAG, "Starting OTA update. This will take some time to "
-                    "complete...");
-      size_t written = Update.writeStream(client);
 
-      if (written == contentLength) {
-        ESP_LOGI(TAG, "Written %d bytes successfully", written);
-      } else {
-        ESP_LOGI(TAG, "Written only %d of %d bytes, OTA update cancelled.",
-                 written, contentLength);
-        // Retry??
+    size_t written;
+
+    if (Update.begin(contentLength)) {
+
+      int i = FLASH_MAX_TRY;
+      while ((i--) && (written != contentLength)) {
+
+        ESP_LOGI(TAG,
+                 "Starting OTA update, attempt %d of %d. This will take some "
+                 "time to complete...",
+                 i, FLASH_MAX_TRY);
+
+        written = Update.writeStream(client);
+
+        if (written == contentLength) {
+          ESP_LOGI(TAG, "Written %d bytes successfully", written);
+          break;
+        } else {
+          ESP_LOGI(TAG,
+                   "Written only %d of %d bytes, OTA update attempt cancelled.",
+                   written, contentLength);
+        }
       }
 
       if (Update.end()) {
+        
         if (Update.isFinished()) {
           ESP_LOGI(TAG, "OTA update completed. Rebooting to runmode.");
           ESP.restart();
@@ -209,6 +222,7 @@ void processOTAUpdate(const String &version) {
       } else {
         ESP_LOGI(TAG, "An error occurred. Error #: %d", Update.getError());
       }
+
     } else {
       ESP_LOGI(TAG, "There isn't enough space to start OTA update");
       client.flush();
diff --git a/src/paxcounter.conf b/src/paxcounter.conf
index 92380894..1c6c6948 100644
--- a/src/paxcounter.conf
+++ b/src/paxcounter.conf
@@ -67,6 +67,7 @@
 
 // OTA settings
 #define WIFI_MAX_TRY                    20      // maximum number of wifi connect attempts for OTA update [default = 20]
+#define FLASH_MAX_TRY                   3       // maximum number of attempts for writing update binary to flash [default = 3]
 
 // LMIC settings
 // define hardware independent LMIC settings here, settings of standard library in /lmic/config.h will be ignored