Exec bug? Design limit? Or Editor limit? Lyons, Tigers, and Bears

Ok, I could not resist the Lyons, Tigers, and Bears humor...

I have seen a few forum references to exec node dropping stdout, such that what is outputted is just part of what stdout should be, as compared to say output via Linux console. Or... is this just an artifact of how the wire-editor displays data in the debug window? Had not tripped over this until I started working on something that just happens to generate a lot of text to stdout.

For example, below is output via Linux console...

# iwlist wlan0 scan
wlan0     Scan completed :
          Cell 01 - Address: [redacted]
                    Channel:8
                    Frequency:2.447 GHz (Channel 8)
                    Quality=70/70  Signal level=-39 dBm
                    Encryption key:on
                    ESSID:[redacted]
                    Bit Rates:1 Mb/s; 2 Mb/s; 5.5 Mb/s; 11 Mb/s; 18 Mb/s
                              24 Mb/s; 36 Mb/s; 54 Mb/s
                    Bit Rates:6 Mb/s; 9 Mb/s; 12 Mb/s; 48 Mb/s
                    Mode:Master
                    Extra:tsf=0000000000000000
                    Extra: Last beacon: 40ms ago
                    IE: Unknown: 001E446163687368756E64204469676974616C5F6F70746F75745F6E6F6D6170
                    IE: Unknown: 010882848B962430486C
                    IE: Unknown: 030108
                    IE: Unknown: 2A0104
                    IE: Unknown: 2F0104
                    IE: IEEE 802.11i/WPA2 Version 1
                        Group Cipher : CCMP
                        Pairwise Ciphers (1) : CCMP
                        Authentication Suites (1) : PSK
                    IE: Unknown: 32040C121860
                    IE: Unknown: 2D1AEC181BFFFF000000000000000000000000000000000000000000
                    IE: Unknown: 3D1608080400000000000000000000000000000000000000
                    IE: Unknown: DD090010180209F02C0000
                    IE: Unknown: DD180050F2020101800003A4000027A4000042435E0062322F00
          Cell 02 - Address: [redacted]
                    Channel:64
                    Frequency:5.32 GHz (Channel 64)
                    Quality=51/70  Signal level=-59 dBm
                    Encryption key:on
                    ESSID:[redacted]
                    Bit Rates:6 Mb/s; 9 Mb/s; 12 Mb/s; 18 Mb/s; 24 Mb/s
                              36 Mb/s; 48 Mb/s; 54 Mb/s
                    Mode:Master
                    Extra:tsf=0000000000000000
                    Extra: Last beacon: 40ms ago
                    IE: Unknown: 001F446163687368756E64204469676974616C355F6F70746F75745F6E6F6D6170
                    IE: Unknown: 01088C129824B048606C
                    IE: Unknown: 050400010000
                    IE: IEEE 802.11i/WPA2 Version 1
                        Group Cipher : CCMP
                        Pairwise Ciphers (1) : CCMP
                        Authentication Suites (1) : PSK
                    IE: Unknown: 2D1AEC081AFFFF000000000000000000000000000000000000000000
                    IE: Unknown: 3D1640080400000000000000000000000000000000000000
                    IE: Unknown: DD090010180201F02C0000
                    IE: Unknown: DD180050F2020101800003A4000027A4000042435E0062322F00

Here is output received from exec node doing the same command as above. I tried both exec modes, both spawn mode and default mode seemed to truncate the output?

wlan0     Scan completed :
          Cell 01 - Address: [redacted]
                    Channel:8
                    Frequency:2.447 GHz (Channel 8)
                    Quality=70/70  Signal level=-40 dBm  
                    Encryption key:on
                    ESSID:[redacted]
                    Bit Rates:1 Mb/s; 2 Mb/s; 5.5 Mb/s; 11 Mb/s; 18 Mb/s
                              24 Mb/s; 36 Mb/s; 54 Mb/s
                    Bit Rates:6 Mb/s; 9 Mb/s; 12 Mb/s; 48 Mb/s
                    Mode:Master
                    Extra:tsf=0000000000000000
                    Extra: Last beacon: 20ms ago
                    IE: Unknown: 001E446163687368756E64204469676974616C5F6F70746F75745F6E6F6D6170
                    IE: Unknown: 010882848B962430486C
                    IE: Unknown: 030108
                    IE: Unknown: 2A0104
                    IE: Unknown: 2F0104
                    IE: IEEE 802.11i/WPA2 Version 1
                        Group Cipher : CCMP

What does the '```' mean? That the debug window is limiting results? So not really an exec bug? Or limit?

These are straight cli commands, not python, so the buffered python output is not applicable here. I believe 'file in' can be used to avoid this issue, but the question is, is this an exec bug or design limitation? Or something else?

If this is a limit of some type via exec? The issue I see is you may never know when exec mode is cutting output, when the expected output is highly random in volume. So this can't be something that should be ignored right? Is this something on the fix it list? If it is a bug or such?

I dont see this in the output.

In the debug window, in an individual (single) message debug item, it displays 3 dots when it appears the output has been truncated. So some reason it did not transfer the dots when I pasted the text example in the forum question text box.

From which output ? Did you attach 3 debug nodes with its ouput set to complete msg object ?

I think this is a limitation of the debug node. It will truncate messages above a certain size. To test that the exec node gives you the full output use for example a file node and write msg to a file. This should than have the full output.

The Debug sidebar does truncate messages to limit how much data is passed to the editor each time. The dots you see are an indication of that.

1 Like

Cool, so the only way to guarantee the full output is to route, same, to say a file object, which I have done.

The msg in the flow always contains the full output. We limit in the debug window to try limit the server to browser socket from getting saturated. You can change the limit in your settings.js file.

1 Like

Right, I figured it was a limit, after I linked the file node, and was capturing the output as expected. But I wanted to ask... to confirm behavior, hate assuming stuff, even if it seems obvious at times. Never know when an assumption, innocent or otherwise, bites you in the south end. :slight_smile:

I seem to remember that if you send it to the console it will all be there, but not certain.

That would make sense too... since the limit is really a design artifact of debug window.