SFTP, SOAP/XML, exFAT, DoH, INT, HMP, XML

  • Ah, reading logs is a good idea. Wondered why sftp counldn't chroot user group to alternate path, but it seems that the chroot path must be owned by root. Yep, it's immediately obvious when you just read the logs.
  • In world of interesting SOAP/XML integration. First time ever, HTTP 415 Media type is unsupported. That's because they wanted the content-type: application/soap+xml delivered as text/html.
  • Another interesting observation is that exFAT on Linux doesn't actually support sparse files, or at least isn't able to create those. Space is actually reserved and written to on disk when allocating. No, I didn't go and test it, before I noticed this would be a problem and then tested and confirmed what I assumed based on my observations.
  • More observations since Outlook email infrastructure got renewd: Now own address mail also works flawlessly and doesn't get flagged as spam all the time. Awesome. kw: Outlook, SMTP, spam, filtration, improvements, correct, operation
  • Studied: Fault Tolerance, Graceful Degradation and Bitrate peeling. Great especially when there's varying network / radio conditions.
  • Checked out DNS over HTTP (DoH) .
  • PSD2 - Account Information Service (AIS) seems like a service, which could benefit us. Yet when this post comes out of my backlog, it might be that it's already implemented. But it remains to be seen.
  • Read long and interesting article about Finnish SIGNIT and COMINT. It contained leaked and classified information leaked by someone whom got access to the information. - Interesting mess. It seems that after the initial discussions publishing of that leak series ended right there.
  • Studied with friends European public Internet Surveillance and Censorship in Europe. It seems that Finland is just following what others have been doing all the time. Of course this it not new at all.
  • Mirai botnet retrospective analysis. Very nice work indeed.
  • Had long discussions with colleagues about Heterogenous Multi-Processing (HMP) and ARM big.LITTLE architecture and similar solutions providing alternating performance when required.
  • One project had really annoying timezone issues. Simple fix was to go through whole project, and make everything to use UTC c-timestamps and only convert that to local time when required. These things are technically simple, but can cause huge mess, unless code and data is consistent. Especially if project isn't being properly tested in different time zones etc. I guess this is also very normal fail, if it's not especially mentioned in requirements.
  • Annoying XML bug. Great example why copy paste code is very bad idea, especially when done in slightly sloppy fashion. Even if functions would be ridiculously short, it's better to replace certain things with methods / functions which get the job done correctly, instead of copy pasting. In this case problem was quite simple. Each copy pasted segment required four similar references to work correctly. But one of those wasn't correctly updated after copy paste. This lead to situation where one if statement compared wrong data set. Of course the wrong data set happened to be one, which often contained similar data than the correct data set. Leading to situation where in light unit testing everything seemed to work correctly. Also all lines were activated by the unit testing. But in reality, when data was 'just correct' it lead to situation where already processed data got lost. - Duh, all it took was changing a single letter in code and we're all good. But it took quite a while to find that problem. Even after realizing that something was missing from the output, it was obvious that logic were flawed somewhere in the code base. - I fixed it by changing the copy pasted code into function which requires only single references being passed.

2019-04-14