Is there any way to check if the device has internet connection?

Questions / Help
1

How can I check if the device I am currently working on is connected to the internet. Is there any library that I can use?

2

How do you define “connected to the internet”?

As this question is not easily answerable, I’d just try to open a connection to the desired target. Either you can reach your target or you can’t.

Just lets look back a couple of days, an important node in germany blacked out for 4 hours. Germany was essentially offline for about 2 hours before everything got rerouted.

Still, technically my WiFi-Card was connected to the internet via my fritz-box.

3

I’d just try to open a connection to the desired target. Either you can reach your target or you can’t.

That’s similar to how reachability libs work on ios, so I guess it’s the most convenient approach.

EDIT Actually, I’m wrong.

From Reachability

[…] it demonstrates how to know when IP can be routed and when traffic will be routed through a Wireless Wide Area Network (WWAN) interface such as EDGE or 3G. Note: Reachability cannot tell your application if you can connect to a particular host, only that an interface is available that might allow a connection, and whether that interface is the WWAN.

So, I guess, the libraries on top of it allow for checking the connection status to a particular host …

4

I’m not sure about iOS development at all, but from what you have quoted, this seems to be more like “If I try to access this host, will it be routed through mobile network or the WiFi?”.

5

Yeah, I was wrong.

I thought it tried to establish a connection with the remote host for some reason. But it just shows the interface that would be used for this.

6

Actually the device is always connected. I have to do a simple check like to ping a website so I can know if there is real connection or no.

7

ping a website

Just ping or assert a 200 http response?

8

Do you want to ping (ICMP ECHO request) or know if a website is reachable? One can easily work without the other for the same target host.

Therefore my suggestion remains, just do the request and handle errors (or let it crash).

9

This is what I needed. It is okay to use for test purposes.

defp net_status() do                                                                                                                       
  case HTTPoison.head("www.google.com") do                                                                                                 
    {:ok, _} -> Logger.debug("Internet connection: OK")                                                                                    
    {:error, _} -> Logger.error("No internet connection!")                                                                                 
  end                                                                                                                                      
end
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