ADD command with network path in Windows Containers Dockerfiles - docker

I'm creating some Windows Container images that I need but the source file I want to ADD are in a network share \\myserver\myshare\here.
I've tried in any possible way but I always get the message error The system cannot find the path specified.
Is it because I have not yet found the right way to set it or is it that it is just not possible?
From the Docker site:
Multiple resource may be specified but if they are files or directories then they must be relative to the source directory that is being built (the context of the build).
Is that why I can't accomplish what I need?
Full error message: GetFileAttributesEx \\myserver\myshare\here\: The system cannot find the path specified.

Whatever you ADD or COPY must be in the docker build context.
When you do this:
docker build .
That directory param (the . in the example) is the context that is copied and sent to the Docker daemon. Then the docker daemon use those files to COPY or ADD. It won't use any file that is not in that context.
That is the issue that you are experiencing. I'm not sure how you can solve it anything than copying the files from \\myserver to your build directory.
ADD is capable of download files by providing an URL (should investigate if it supports Windows' shares)

Related

Add file to Docker Image

I am new to docker, and I have created a docker image for sparq spatial reasoning toolbox using pull docker pull dwolter/sparq:latest, (Gethub: https://github.com/dwolter/SparQ).
The sparq catains set of calculus in form of lisp files, which can be used to do spatial reasoning, using the Sparq docker image in the windows docker.
The thing that I have developed my own calculi and I need to add it to the image.
I have tried to do that using the cp command but I could not. Because I don't know the path of the file indside the image, in otherwords, where I should place the file inside the image, also when place it in the main root of a container, and applied the command commit, it generated error: access denied by ther resource.
first question is :
Does the path in the image has the same path in the sparq application folder which I have already downloaded?
Also, How I can add this culculi (lisp file) to the image in docker ?
P.s. I have also downloaded the folder which contains the application (sparq and all its files and folders) and I have placed my calculi inside the appropriate folder ( caculi folder and it works fine).
I run it using Linux command line and it works fine, Now I need to use this application through the docker.
As I have the application on folder.
Can I create an image on my own based on the folder that contains the application ?
The Sparq Dockerfile indicates the working directory is set to /root/sparq. That means, you should be able to run the following copy command in your own Dockerfile to place your lisp file in the same place you have locally, the place where all other Calculi lisp files are located:
FROM dwolter/sparq
COPY ./path/to/my/Calculi/file.lisp ./Calculi
Then run docker build . to build a Docker image containing sparq and your file. Then, it should be ready to run.
NOTE: I am not familiar with lisp. If it needs to be compiled, the compile command will need to be added to the Dockerfile after the COPY.

Copy directory into docker build no matter if empty or not - fails on "COPY failed: no source files were specified"

I have directory csv in context directory of docker build. I want to copy it into docker image in all circumstances (for empty directory in host an empty directory inside image is created, for nonempty directory in host it is copied with all content).
The COPY csv/* /csv/ gives COPY failed: no source files were specified error when the directory is empty.
Similar questions I found on SO are differing from my case in either setup or intention (multistage build, copying existing jar, certainly existing file) so I choose Q&A-style here rather than messing question with unrelated answer. This Github issue is also related.
The solution is to use
COPY csv/. /csv/
This question gave me a hint (although the behavior desired by me is unwanted for its OP).

.dockerignore workflow unclear

I have a question about the .dockerignore workflow which I wasn't really able to understand while browsing through the documentation and different internet topics.
Have the following folder structure:
home
|
|- folder_1
|- folder_2
Inside my dockerfile I want to copy the contents of home directory, so I use
COPY ./ /home
Inside .dockerignore I have:
*
!folder_1
!folder_3
I am referring to a non-existent folder - folder_3, which is supposed to be copied, right?
I ran it and it looks like there's no problem with that, thus .dockerignore somehow manages this situation.
If I tried to do the same thing without using .dockerignore, targeting a non-existent directory I would get an error.
If anybody can please clear this workflow, or if a duplicate, please attach some information so I can educate myself.
Thanks in advance!
First of all, .dockerignore works like .gitignore. Inside these files you set the rules on the basis of which files should be added, and which should not.
In your scenario you COPY the whole home directory which consists of folder_1 and folder_2. Your .dockerignore file sets the following rules:
* # ignore all files/directories
!folder_1 # do not ignore folder_1
!folder_3 # do not ignore folder_3
Regardless of whether there is a folder_1 or folder_3 in your local home directory or not, it won't show you any errors, because it just tries to find particular files/directories that are inside .dockerignore. If it finds this file/directory, it applies the rules. If it doesn't find this file/directory, it doesn't do anything with it.
Hope that's a little bit more clear now.
You'll occasionally see reference to a Docker build context. The build has two steps:
The docker build client application creates a tar file of its directory parameter, and sends it in an HTTP request to the Docker daemon.
The Docker daemon unpacks the tar file, finds the Dockerfile in it, and runs it using the file content it was given.
.dockerignore only affects the first step: it keeps docker build from sending the Docker daemon particular files. The .dockerignore file doesn't require there to be a folder_3 directory, it just says that if there is one it shouldn't be excluded. The second step on the Docker daemon side doesn't use .dockerignore at all, and when you COPY . /somewhere it copies the entire build context; that is, whatever was sent in the API request.
There are a couple of practical consequences of this workflow. If you have a very large local directory it can take time to send it to the Docker daemon, and the Docker daemon keeps a duplicate copy of it during the build, so it's often worthwhile to .dockerignore your .git directory and a build tree. This setup is also how docker build works with a Docker daemon on a different system or in a VM, and it's why if you try to COPY a file by name that doesn't exist (COPY folder_3 somewhere) you get an error message referencing a Docker-internal path.

How to add Chromedriver to existing Docker?

I've personal ASP.NET Core project which scrapes data from the web using Selenium and Chromium and saves it in local sqlite database.
I want to be able to run this app in Docker image on my Synology NAS. Managed to create and run Docker image (on my Mac), it displays data from sqlite db correctly, but getting error when trying to scrape:
The chromedriver file does not exist in the current directory or in a directory on the PATH environment variable.
From my very limited understanding of Dockers in general, I understand that I need to add chromiumdriver inside the docker somehow.
I've searched a lot, went trough ~30 different examples and still can't get this to work.
Any help is appreciated!
You need to build a new image based on the existing one, in which you add the chromedriver binary. In other words you need to extend your current image.
So create a directory containing a Dockerfile and the chromedriver binary.
Your Dockerfile should look like this:
FROM your_existing_image_name:version
COPY chromedriver desired_path_inside_container
Then open a terminal inside this directory and execute:
docker build -t your_existing_image_name:version++ .
After that you should be able to start a container from the newly created image.
Some notes:
I have assumed that your existing image has been tagged with a version. If it is not the case then remove :version from Dockerfile
Similarly, remove :version++ from the build command. However, is a good practice to include versioning in your images.
I have not add any entrypoint assuming that you do not need to change the existing one.

Why is my dockerfile not copying directories

in my dockerfile I have these two lines:
ADD /ansible/inventory /etc/ansible/hosts
ADD /ansible/. /ansiblerepo
The first line works, as I can run the container and see my hosts file has been populated with all the ips from my inventory file.
The second line doesn't appear to be working though. I'm just trying to copy all the files/subdirectories of ansible and copy them over to the ansiblerepo directory inside the new container.
There are no errors while building the image, but again ansiblerepo is just an empty directory and nothing has copied over to it. I assume I'm just missing a back slash or something.
Docker ADD and COPY commands work relative to the build directly, and only for files in that directory that weren't excluded with a .dockerignore file. The reason for this is that builds actually run on the docker host, which may be a remote machine. The first step of a docker build . is to package up all the files in the directory (in this case .) and send them to the host to run your build. Any absolute paths you provide are interpreted as relative to the build directory and anything you reference that wasn't sent to the server will be interpreted as a missing file.
The solution is to copy /ansible to your build directory (typically the same folder as your Dockerfile).
Make sure that in your ".dockerignore" file, it does not excluded everything. usually, dockerignore file has these lines
*
!obj\Docker\publish\*
!obj\Docker\empty\
this means that everything is ignored except publish and empty folders.
Removing trailing /. from source directory should fix the ADD command.
On a related note, Docker Best Practices suggest using COPY over ADD if you don't need the URL download feature.

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