ESPAsyncWebServer.h with esp32

Question

I am new to esp32 programming. I wanted to try to make a server.

I tried to use the ESPAsyncWebServer library.

I got this error

In file included from C:\Users\User\Documents\Arduino\server\server.ino:2:0:

Multiple libraries were found for "WiFi.h"
sketch\ESPAsyncWebServer.h:33:22: fatal error: AsyncTCP.h: No such file or directory

Used: C:\Users\User\Documents\ArduinoData\packages\esp32\hardware\esp32\1.0.4\libraries\WiFi
compilation terminated.

Not used: C:\Program Files\WindowsApps\ArduinoLLC.ArduinoIDE_1.8.33.0_x86__mdqgnx93n4wtt\libraries\WiFi
exit status 1
Error compiling for board ESP32 Wrover Module.

Can someone help me and tell me what is the correct way to install liberals because I have a feeling that I am doing it wrong.

Answer 1

For others struggling with this question, my answer is "don't use unsuppored web servers" - ESPAsyncWebserver has too many leaks, race conditions, and security issues to be seriously considered in 2024. (The last submitted patch was > 2 years ago, which is far too long to rely on in modern web world.)

My vote goes to https://github.com/hoeken/PsychicHttp. The API is almost identical (search /AsyncWebServerRequest/PsychicRequest/g and you're 90% done; a PR like https://github.com/Aircoookie/WLED/pull/3726/files demonstrates the other renames)

• HTTPS supported out of the box.
• WAY faster - see requests/s (blue) vs. EAW (green) at https://github.com/hoeken/PsychicHttp/blob/master/benchmark/performance.png
• Better latency - see https://github.com/hoeken/PsychicHttp/blob/master/benchmark/latency.png
• No known crashes. EspAsyncWebServer reproducibly crashes under more than simplest of loads.
• Crashes in EAW with fixes submitted aren't integrated: https://github.com/me-no-dev/ESPAsyncWebServer/issues/1172 or https://github.com/me-no-dev/ESPAsyncWebServer/issues/1167
• Better performance in low memory conditions. (With base-level ESP32, it's almost hard to NOT be in a low-memory condition...)
• No annoyance with % delimiter, which is used to start templating engine that can't be turned off. This causes problems in things like serving css when you set the width to "25%", but it eats the % and just sets the width to 25 pixels.
• YouTube Channel H4 Plugins has an entire video on the numerous problems with ESPAsyncTCP and ESPAsyncWebServer. Even if you don't pick their package as the replacement, all the criticisms (silent failure without logging errors, missing synchronization primitives, poor handling under memory pressure, reliance upon order of packets (!!!), silent discard of data < or > certain sizes, etc.) are still valid.

With anyone asking this question, I'll say that since you're just starting, there's no reason to start behind the line: Use PsychicHTTP for ESP32.

Answer 2

You will need to install both libraries ESPAsyncTCP and ESPAsyncWebServer, since the latter is dependant on the first.

You can install them by:

1. Downloading the zip files from github:

   • https://github.com/me-no-dev/ESPAsyncWebServer
   • https://github.com/me-no-dev/ESPAsyncTCP

2. In your Arduino IDE go to Sketch > Include Library > ZIP-Library and select the libraries you just downloaded.

Answer 3

Your compile error says that you are lacking the AsyncTCP library. You can find it here: https://github.com/me-no-dev/AsyncTCP