Monthly Archives: Mai 2020

Stupid business mistakes #3 :: Assuming things will work forever (The value of monitoring)

Things work, and there is no mistake about that!But, due to the universe constantly increasing in entropy, they do not work forever. They need to be supplied with your attention, knowledge and energy, so that they can continue to work.You know how it is, our bodies are pretty amazing – but at some point they [...]

By | Mai 30th, 2020|Stupid business mistakes|Kommentare deaktiviert für Stupid business mistakes #3 :: Assuming things will work forever (The value of monitoring)

Dealing with NIL in JSON::Any in Crystal Lang

One of the challenges when developing with Crystal is that it is not as forgiving about data types as, say, Python or Ruby.nil will keep you occupied.The following error message:cast from Nil to String failed, at /usr/share/crystal/src/json/any.cr:220:5:220can be solved by:# cast to string, THEN check if it is nil if !(shopify_data[spid]["billing_address"]["address2"].as_s? == nil)     name = [...]

By | Mai 30th, 2020|Crystal Language|Kommentare deaktiviert für Dealing with NIL in JSON::Any in Crystal Lang

Chromium exit code -5

While running Chromium with chromium-browser --display=:0 https://www.picockpit.comwill allow you to start Chromium from an SSH connection (and it will output to the main display in the X Server), this will fail when you try to run it with subprocess.Popen in Python:"command": ["chromium-browser", "--display=:0", “https://picockpit.com”](this is part of the JSON format I have specified for PiControl [...]

By | Mai 19th, 2020|Development|Kommentare deaktiviert für Chromium exit code -5

secure command execution with Python: subprocess.Popen

Security is important for me while developing the picockpit-client. The following applies to Linux systems (but probably is applicable to all Unix like systems, including macOS)Python allows to run external commands using the subprocess module.import subprocessIn the upcoming version of PiCockpit, users will be able to create their own buttons (simply editing a JSON file [...]

By | Mai 15th, 2020|Development, Python|Kommentare deaktiviert für secure command execution with Python: subprocess.Popen

Stupid business mistakes #2: trying to cheat people (a new kind of spammer)

A bait and switch site, which was supposed to show me some information about Python code.“Click allow if you are not a bot”. Abusing the Captcha to display notifications (probably spam advertising?) is definitely a clever idea. (From the technical and machination point of view)Why does the person who is behind this not direct their [...]

By | Mai 15th, 2020|Stupid business mistakes|Kommentare deaktiviert für Stupid business mistakes #2: trying to cheat people (a new kind of spammer)

TermiShell: a web-based shell for the Raspberry Pi (development notes)

IntroductionIn the course of development of PiCockpit, I am going to add a web-based Terminal called TermiShell.TermiShell icon, by: Stephanie Harvey via unsplash.com TermiShell is going to allow you to log into your Raspberry Pi using PiCockpit.com (and the picockpit-client) – no additional application required on either side. This should be very comfortable, especially when [...]

By | Mai 5th, 2020|Development, Python, Raspberry Pi Blog, Raspberry Pi Embedded Development|Kommentare deaktiviert für TermiShell: a web-based shell for the Raspberry Pi (development notes)