I have an existing Windows desktop application written in C++ that needs to add support for SNMP so that a few pieces of status information are available on some SNMP OIDs. I found the net-snmp project and have been trying to understand how this can best fit into the existing program.
Questions:
Do I need to run snmpd, or can I just integrate the agent code into my application? I would prefer that starting my application does everything necessary rather than worry about deploying and running multiple processes, but the documentation doesn't speak much about doing this. The net-snmp agent daemon tutorial has an option for running the sample code as the full-agent rather than sub-agent, but I'm not sure about any limitations of doing this.
What would the PROs/CONs be for running a full agent in my application vs using snmpd and putting a subagent in my application? Is there a 3rd option I should also consider?
If I can integrate the full agent into the existing program, how do I pass it a configuration file via the API? Can I avoid the config file all together by passing these parameters in via function call instead?
Related
I've created a docker container (ubuntu:focal) with a C++ application that is using boost::filesystem (v1.76.0) to create some directories while processing data. It works if I run the container locally, but it fails when deployed to Cloud Run.
A simple statement like
boost::filesystem::exists(boost::filesystem::current_path())
fails with "Invalid argument '/current/path/here'". It doesn't work in this C++ application, but from a Python app running equivalent statements, it does work.
Reading the docs I can see Cloud Run is using gVisor and not all the system calls are fully supported (link: https://gvisor.dev/docs/user_guide/compatibility/linux/amd64/), nevertheless I would expect simple calls to work: check if a directory exists, create a directory, remove,...
Maybe I'm doing something wrong when deploying my container. Is there any way to work around it? Any boost configuration I can use to prevent it from using some syscalls?
Thanks for your help!
I'm new to Azure-Pipeline and struggling to put together a C++ oriented pipeline that uses camke which properly compiles, run tests and build documentation on Ubuntu, macOS, and Windows.
I managed the macOS and Ubuntu cases rather easily but am struggling with the Windows case not knowing what's installed and what's in system PATH for the given image & container I've selected.
Not being super familiar with the Azure-Platform I'm basically relying on commit-push-run-pipeline every single little change to my YAML file thus wasting time and resources.
I can't imagine that the only way is to blindly try out commands by commit, push and run the pipeline.
I managed to find a basic description of the currently (hopefully) available images here following the included software link for Windows link yoou end up on a comprehensive list of what's supposedly installed (I have some doubts on whether this documentation actually matches the content of the image). Calling some of those tools like cmake and choco, present in the above list, failed. Whether or not they're actually installed and in system PATH I have no idea.
Q1: Is there any way to locally test out an Azure-Pipeline YAML?
Q2: Is there any way to figure what is actually installed on a given image/container (without issuing a DIR /s from the root folder??)
Q3: Is it possible to connect to a running container (or is it a VM???) instance and directly tinker with it?
Q4: Alternatively, is it possible to run such an image locally (Docker)? Does it imply execution on a Windows machine or is that a standalone VM image?
EDIT: Found out about this question, although doesn't quite answer mine: Is there a tool to validate an Azure DevOps Pipeline locally?
Q1: Is there any way to locally test out an Azure-Pipeline YAML?
The answer is yes. You could create your private agent to execute the Azure-Pipeline YAML.
Self-hosted agents
Q2: Is there any way to figure what is actually installed on a given
image/container (without issuing a DIR /s from the root folder??)
Just as you know, we could check the document Software for the software installed on the agent. If you want to know the install the path of some software, you could check the debug log from the build task. For example, cmake. We could check the build log from the cmake task:
Q3: Is it possible to connect to a running container (or is it a
VM???) instance and directly tinker with it?
For the hosted agent, I am afraid the answer is not.
Q4: Alternatively, is it possible to run such an image locally
(Docker)? Does it imply execution on a Windows machine or is that a
standalone VM image?
The answer is yes, we could Run a self-hosted agent in Docker. And it imply execution on a Windows machine.
I don't know much about web development and cloud computing. From what I've read when using Cloud functions as the webhook service for dialogflow, you are limited to write code in just 1 source file. I would like to create a real complex dialogflow agent, so It would be handy to have an organized code structure to make the development easier.
I've recently discovered Cloud run which seems like it can also handle webhook requests and makes it possible to develop a complex code structure.
I don't want to use Cloud Run just because it is inconvenient to write everything in one file, but on the other hand it would be strange to have a cloud function with a single file with thousands of lines of code.
Is it possible to have multiple files in a single cloud function?
Is cloud run suitable for my problem? (create a complex dialogflow agent)
Is it possible to have multiple files in a single cloud function?
Yes. When you deploy to Google Cloud Functions you create a bundle with all your source files or have it pull from a source repository.
But Dialogflow only allows index.js and package.json in the Built-In Editor
For simplicity, the built-in code editor only allows you to edit those two files. But the built-in editor is mostly just meant for basic testing. If you're doing serious coding, you probably already have an environment you prefer to use to code and deploy that code.
Is Cloud Run suitable?
Certainly. The biggest thing Cloud Run will get you is complete control over your runtime environment, since you're specifying the details of that environment in addition to the code.
The biggest downside, however, is that you also have to determine details of that environment. Cloud Funcitons provide an HTTPS server without you having to worry about those details, as long as the rest of the environment is suitable.
What other options do I have?
Anywhere you want! Dialogflow only requires that your webhook
Be at a public address (ie - one that Google can resolve and reach)
Runs an HTTPS server at that address with a non-self-signed certificate
During testing, it is common to run it on your own machine via a tunnel such as ngrok, but this isn't a good idea in production. If you're already familiar with running an HTTPS server in another environment, and you wish to continue using that environment, you should be fine.
I have an automation framework that uses static html pages within its project directory to perform certain aws operations such as dynamoDB scan and Aws Lambda executions. Due to some performance bottleneck in a dependent api component for the test we are trying to move the framework to an ec2 instance with Amazon linux and run the tests from there.
Since we have methods in the TestNG class that actually uses selenium web driver to spin up a browser and open up the static page in order to perform the required Aws operations I am pretty sure this test is going to run into issues.
There are two potential approach I see for solving this issue:
Implement AWSUtil classes and use necessary aws clients to replace the web dependent logics (Will require some effort and re-engineering)
Use a headless chrome browser (or any compatible one) in order to run the web dependent steps.
I am pretty sure that number 1 can be easily achieved, just a matter of time and effort. However, would love to know if there is an easy way of accomplishing #2 since this would not require any code rewrite.
We got the same issue and been successful with puppeteer,
https://github.com/GoogleChrome/puppeteer
If you don't want to install the latest version of node, you can dockerize your tests.
puppeteer can run headless or with browser.
Hope it helps.
There is no need to change anything in your tests, just the setup and the execution. The tests can run headlessly on a Continuous Integration (CI) server. There is no out-of-the-box setup since there is no display output for the browser to launch in. However with Xvfb you can launch the browser virtually. Straight from the docs:
Xvfb (short for X virtual framebuffer) is an in-memory display server for UNIX-like operating system (e.g., Linux). It enables you to run graphical applications without a display
Depending from do you want to keep Xvfb running in the background until the process is killed, there are two options:
Xvfb :99 &
export DISPLAY=:99
run-your-tests-here
or
xvfb-run run-your-tests-here
Here is a Linux tutorial. I am using this for my Docker based Jenkins setup and works like a charm, every time.
I was wondering about the best way to deliver private web service instances to lots of users, so the user would always be able to connect to their own offline version of a service, just like running a web service from visual studios while debugging. I was struggling with setting this up in VS2013 even with the many online tutorials, but I am not sure if its not working because it was never supposed to work this way.
I have provided this in-depth explanation of my issue as i am not sure i am going about this in the right way and would appreciate feedback:
Background:
I have a web service to interface with an engine. This deals with the front-end and builds a set of commands for how to make a CAD model. These commands are for controlling the 3rd party CAD software's API. Therefore the engine can be seen to have two main functions -
Build the CAD's API instructions, which can be saved for later
Execution, where it catches the instance of the CAD software
running on the same computer and it builds the model.
The second part is restricted for the general public. Only our in-house users should be able to use it. However, they want to have an otherwise identical front-end and user experience.
The problem is, if they connect to the same engine as the public, which exists on our main server, then the engine will be looking for an instance of the CAD package on the same machine as itself - i.e the server, as stressed in the emboldened point above. What should happen is the engine finds the CAD instance running on the machine that the controlling UI is based on and it uses that for its target. I have spoke to the CAD API support and they say they do not know how to do that.
And so we get to my solution of providing an offline stand alone of my web service on each of the employees computers. This means the front-end will check at the start of the session if a localhost connection is available. If not it will use the main address, which takes it to my server. Otherwise it uses the local engine which will look perform the default behavior of looking for a CAD package on the same machine as itself. Because its locally installed that is now the right machine and it will find the CAD instance of the user successfully.
Final points:
The engine cannot be accessed by the UI directly as i am using
Unity3D for the front-end and there is .Net compatibility issues.
I need a completely self contained version of the software in the
future anyway, so eventually i have to deal with having the engine
accessed locally
I ended up using IISExpress. I got the user to install this and then get them to call a batch file installer i made which sets up the config file and moves my web project to the correct directory.