Short Version : How to enable background HTTP/Network Interface when only HotSpot is connected to a device. (use case : WiFi and Data are On but not connected to any Network).
I am working on an Flutter app for an esp32 based iot solution and my use case involves being able to communicate with ESP without using WiFi/Data and only through hotspot. Thus far, I have successfully been able to talk to a esp32 using mDNS + HTTP when esp32 is connected via android device’s hotspot (Scenario 1 and 2 in picture below).
But when if there are no active connections (ie WiFi or Data) on the android, it appears as if the wifi/HTTP interface shuts down, as I am neither able to make any HTTP connections with esp, and neither able to connect to localhost of the browser from my app. (scenario 3)
I confirmed the interface shutdown issue by connecting the wifi of Android Device to another hotspot(SSID : laptopHotspot) from my laptop, which was disconnected from the internet. Again, all communication between esp and samsung were back to normal. (scenario 4)
I am hoping if someone can guide me or point me in the right direction as to why no HTTP communications work, when there are no active wireless communications (even though wifi is on, just not connected to any network, ie why is network connection mandatory, and how to bypass it?)
Imgur LInk : https://imgur.com/RwtVP1e