I was recently trying to containerize an application that uses three services. When starting their containers separately with docker run, I also need to put them in the same network otherwise they can’t communicate. But I just wrote a docker-compose.yaml file to run them at the same time and they can communicate with each other… Read More Does docker compose automatically put the containers in the same network?

I have to create this green container. How can I achieve that? I tried border-radius but I can’t. >Solution : Use like below First create class for decoration class BadgeDecoration extends Decoration { final Color? badgeColor; final double? badgeSize; final TextSpan? textSpan; const BadgeDecoration( {@required this.badgeColor = Colors.black, @required this.badgeSize, @required this.textSpan}); @override BoxPainter createBoxPainter([VoidCallback?… Read More Flutter Container triangle design

I’m sorry I just started learning about HTML and I was confused why this happened. I don’t know which line to copy here so I’m sorry I just dump the file here. So I have 20 question with 4 or 5 radio option, the first 11 question is inside the container, but the rest of… Read More Container not expanding for questionnaire

I’m reading the book The docker book version v1.2.0, in chapter 6 in page 178 it said that if you deleted the last container that uses a volume, the volume will disappear. Be carful about deleting containers that might hold volumes with data you need But when I tried it, the volume isn’t deleted. Is… Read More Is docker volume deleted if the container is deleted?

One can loop over a list by both: #include <iostream> #include <list> using namespace std; int main() { list<int> alist{1, 2, 3}; for (const auto& i : alist) cout << i << endl; list<int>::iterator i; for (i = alist.begin(); i != alist.end(); i++) cout << *i << endl; return 0; } Mostly I don’t use… Read More Using iterators but with same amount of loc?

I made a small container that runs a single shell script. Its Dockerfile is as follows: FROM centos:centos7.9.2009 RUN mkdir -p /var/lib/test COPY ./ /var/lib/test/ RUN yum -y localinstall /var/lib/test/*.rpm ENTRYPOINT ["sh /var/lib/test/test.sh"] However, when I run the image, it returns the error: #docker run -it test:1.0 /usr/bin/docker-current: Error response from daemon: oci runtime error:… Read More Running a shell from within a docker container succeeds but not as an entrypoint ("no such file or directory" error)

to give context i’m trying to re-implement vector container, and while reading about it’s iterator system requirements, i’ve stumbled upon this requirement from cplusplus reference: can be incremented (if in a dereferenceable state ). the result is either dereferenceable or past-the-end iterator. EX: ++a , a++, *a++ i’ve already overloaded the increment and dereference operators… Read More How to overload an iterator so it can be incremented in a dereferenceable state?

I have a simple docker container that runs a script on startup which exports some variables. So the final line in my Dockerfile is CMD ./startup.sh And startup.sh has #!/usr/bin/env bash export testvar="test" echo $testvar node app.js The output in terminal when running container shows "test" as I would expect. However if I then run… Read More Environment variables empty in Docker container bash

I have a Docker image with an application server running in it. When I’m running in a development environment, I want to run a database server within the same Docker image. However, in production, I want to use my cloud provider’s database service to host my database server. What is the best (preferably officially supported)… Read More How do you manage the variation between local and cloud dependencies within Docker?