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cellerich wants to merge 1 commit into from
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Handle chunked / partial data from server #70

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102 changes: 84 additions & 18 deletions src/network.cpp
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Original file line number Diff line number Diff line change
Expand Up @@ -192,24 +192,33 @@ uint8_t* httpGet(const char* url, std::map<String, String> *headers, int32_t* de
Serial.println("[NET] Invalid URL: null or empty");
return nullptr;
}

// Basic URL format validation
if (strncmp(url, "http://", 7) != 0 && strncmp(url, "https://", 8) != 0) {
Serial.printf("[NET] Invalid URL protocol: %s\n", url);
return nullptr;
}

Serial.printf("[NET] downloading file at URL %s\n", url);

// Wait for WiFi to be stable
waitForWiFi();

bool sleep = WiFi.getSleep();
WiFi.setSleep(false);

HTTPClient http;
http.getStream().setNoDelay(true);
// Set longer timeouts (in milliseconds)
http.setConnectTimeout(10000); // 10 seconds for connection
http.setTimeout(30000); // 30 seconds for overall timeout
delaySleep(timeout_sec);

// Connect with HTTP
http.begin(url);
if (!http.begin(url)) {
Serial.println("[NET] Failed to begin HTTP connection");
WiFi.setSleep(sleep);
return nullptr;
}

if (headers) {
for (const auto& header : *headers) {
Expand All @@ -219,11 +228,50 @@ uint8_t* httpGet(const char* url, std::map<String, String> *headers, int32_t* de

int httpCode = http.GET();

if (httpCode < 0) {
Serial.printf("[NET] HTTP error: %d\n", httpCode);
// Common error codes:
// -1: Connection refused
// -2: Send header failed
// -3: Send payload failed
// -4: Not connected
// -5: Connection lost
// -6: No stream
// -7: No HTTP server
// -8: Too large response
// -9: 3xx redirect (not followed)
// -10: 4xx client error (not success)
// -11: Connection failed / Connection refused
switch (httpCode) {
case -1: Serial.println("[NET] Error: Connection refused"); break;
case -2: Serial.println("[NET] Error: Send header failed"); break;
case -3: Serial.println("[NET] Error: Send payload failed"); break;
case -4: Serial.println("[NET] Error: Not connected"); break;
case -5: Serial.println("[NET] Error: Connection lost"); break;
case -6: Serial.println("[NET] Error: No stream"); break;
case -7: Serial.println("[NET] Error: No HTTP server"); break;
case -11: Serial.println("[NET] Error: Connection failed / refused - check server is running"); break;
default: Serial.println("[NET] Error: Unknown"); break;
}
http.end();
WiFi.setSleep(sleep);
return nullptr;
}

int32_t size = http.getSize();
if (size == -1)
Serial.printf("[NET] Content-Length: %d\n", size);

// Handle chunked encoding (size == -1)
if (size == -1) {
Serial.println("[NET] Chunked encoding detected, will read until end");
}

// For chunked encoding or invalid size, use defaultLen
if (size == -1) {
size = *defaultLen;
else
} else {
*defaultLen = size;
}

// Validate size to prevent buffer overflow attacks
const int32_t MAX_HTTP_BUFFER_SIZE = 1024 * 1024; // 1MB limit
Expand All @@ -241,40 +289,58 @@ uint8_t* httpGet(const char* url, std::map<String, String> *headers, int32_t* de
WiFi.setSleep(sleep);
return nullptr;
}
memset(buffer, 0, size); // Zero out buffer
uint8_t *buffPtr = buffer;

int32_t total = http.getSize();
int32_t len = total;
int32_t bytesRead = 0;

uint8_t buff[512] = {0};

WiFiClient* stream = http.getStreamPtr();
while (http.connected() && (len > 0 || len == -1)) {
size_t size = stream->available();

if (size) {
int c = stream->readBytes(
buff, ((size > sizeof(buff)) ? sizeof(buff) : size));
memcpy(buffPtr, buff, c);
size_t available = stream->available();

if (available) {
int c = stream->readBytes(buff, ((available > sizeof(buff)) ? sizeof(buff) : available));
if (c > 0 && bytesRead < size) {
int toCopy = min(c, size - bytesRead);
memcpy(buffPtr, buff, toCopy);
buffPtr += toCopy;
bytesRead += toCopy;
}

if (len > 0) len -= c;
buffPtr += c;
} else if (len == -1) {
len = 0;
// For chunked encoding, break when no more data available
vTaskDelay(10 / portTICK_PERIOD_MS);
if (!stream->available()) {
break;
}
}
}

Serial.printf("[NET] Bytes read: %d\n", bytesRead);

if (httpCode != HTTP_CODE_OK) {
Serial.printf("[NET] Non-200 response: %d from URL %s\n", httpCode, url);
if (size) {
Serial.printf("[NET] HTTP response buffer: \n\n%s\n\n", buffer);
if (bytesRead > 0) {
Serial.printf("[NET] HTTP response buffer (%d bytes): \n", bytesRead);
// Print first 256 bytes as hex for debugging
for (int i = 0; i < min(bytesRead, 256); i++) {
Serial.printf("%02x ", buffer[i]);
if ((i + 1) % 16 == 0) Serial.println();
}
Serial.println();
}
free(buffer);
buffer = 0;
WiFi.setSleep(sleep);
return nullptr;
}

http.end();
WiFi.setSleep(sleep);

return buffer;
}
}
26 changes: 25 additions & 1 deletion src/trmnl.cpp
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Original file line number Diff line number Diff line change
Expand Up @@ -146,6 +146,30 @@ bool trmnlDisplay(const char *url)
return false;
}

// Handle chunked encoding: strip chunk size prefix and trailing markers
uint8_t *jsonStart = buff;
int jsonLen = defaultLen;

// Skip chunk size line (format: "<hex>\r\n")
if (defaultLen > 4 && buff[0] >= '0' && buff[0] <= 'f') {
// Find end of chunk size line (CRLF)
char *crlf = (char*)strstr((char*)buff, "\r\n");
if (crlf) {
jsonStart = (uint8_t*)(crlf + 2); // Skip "\r\n"
jsonLen = defaultLen - (jsonStart - buff);
Serial.printf("[TRMNL][DEBUG] Skipped chunk size prefix\n");
}
}

// Remove trailing chunk marker (usually just "0\r\n")
if (jsonLen > 4) {
// Check for trailing "0\r\n" or "0\r\n\r\n"
if (jsonStart[jsonLen-1] == '\n' && jsonStart[jsonLen-4] == '0') {
jsonLen -= 4; // Remove "\r\n0\r\n"
Serial.printf("[TRMNL][DEBUG] Removed chunk trailer\n");
}
}

// filter here
JsonDocument trmnl_display_filter;
trmnl_display_filter["filename"] = true;
Expand All @@ -155,7 +179,7 @@ bool trmnlDisplay(const char *url)
trmnl_display_filter["error"] = true;

JsonDocument doc;
DeserializationError error = deserializeJson(doc, buff, defaultLen, DeserializationOption::Filter(trmnl_display_filter));
DeserializationError error = deserializeJson(doc, jsonStart, jsonLen, DeserializationOption::Filter(trmnl_display_filter));
if (error)
{
Serial.printf("[TRMNL][ERROR] JSON Deserialize error: %s\n", error.c_str());
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