In my Spring Boot app, I read some csv file located in resources\data folder and I have the following Dockerfile:
FROM maven:3.8.2-openjdk-17-slim AS builder
# add pom.xml and source code
ADD ./pom.xml pom.xml
ADD ./src src/
# package jar
RUN mvn clean install
# Second stage: minimal runtime environment
FROM openjdk:17-alpine
# copy jar from the first stage
ARG JAR_FILE=target/*.jar
COPY --from=builder ${JAR_FILE} app.jar
EXPOSE 8080
ENTRYPOINT ["java", "-jar", "/app.jar"]
When I run the app after building the container, I get the following error:
"class path resource [data/employees.csv] cannot be resolved to absolute file path because it does not reside in the file system: jar:file:/app.jar!/BOOT-INF/classes!/data/employees.csv"
I think I need to add the resources\data folder to my container. So, how can I do this? What is the most proper way?
Note: I also tried to fix the problem using new ClassPathResource(filename).getInputStream(), but it did not make any sense and still the same problem.
I want to automate the building and execution of a java spring web service by using Docker.
I run a script from the dockerfile that generate a settings.xml file. I want to copy that file in the image, but because RUN create a new container (I think?) the build can't find the generated file.
Here is the begining of my Dockerfile:
FROM ubuntu:20.04
WORKDIR /app
COPY . .
RUN ./script.sh
COPY settings.xml /root/.m2/
and there is the output...
How can I copy the settings.xml file that was generated by my sh script?
Thanks!
COPY copies from the host to the image. If you want to copy from the image to the image, you use the 'normal' cp command.
You're right that each RUN statement runs in a separate shell. But since your generated file is stored in the file system, it'll work if you do it in different RUN statements.
But let's do it in one RUN statement to only get 1 new layer in the image:
FROM ubuntu:20.04
WORKDIR /app
COPY . .
RUN ./script.sh && \
cp settings.xml /root/.m2/
You can also use mv to move the file if you don't need a copy to stay in /app.
By executing RUN script.sh the file will be generated inside the container. Thus it cannot be copied to the image using the COPY Dockerfile command. Instead you could mv the file inside the container to the desired destination:
FROM ubuntu:20.04
WORKDIR /app
COPY . .
RUN ./script.sh \
&& mv /path/to/settings.xml /root/.m2/
I've generated a Dockerfile with Visual Studio. It runs in Visual Studio just fine and now I'm trying to build it from Windows itself (docker build ., and I tried many combinations). Yet I get the following error:
When I change copy to ./client.csproj it does continue and then I get:
What am I doing wrong? I changed Docker Linux to Windows, changed WSL, and restarted everything.
Dockerfile client
Check your .dockerignore file. Possible it ignores needed files for copy command and you get failed to compute cache key error.
.dockerignore may be configured to minimize the files sent to docker for performance and security:
*
!dist/
The first line * disallows all files. The second line !dist/ allows the dist folder
This can cause unexpected behavior:
FROM nginx:latest
# Fails because of * in .dockerignore
# failed to compute cache key: "/nginx.conf.spa" not found: not found
# Fix by adding `!nginx.conf.spa` to .dockerignore
COPY nginx.conf.spa /etc/nginx/nginx.conf
RUN mkdir /app
# Works because of !dist/ in .dockerignore
COPY dist/spa /app
Belts and suspenders.
The way Visual Studio does it is a little bit odd.
Instead of launching docker build in the folder with the Dockerfile, it launches in the parent folder and specifies the Dockerfile with the -f option.
I was using the demo project (trying to create a minimal solution for another question) and struck the same situation.
Setup for my demo project is
\WorkerService2 ("solution" folder)
+- WorkerService2.sln
+- WorkserService2 ("project" folder)
+- DockerFile
+- WorkerService2.csproj
+- ... other program files
So I would expect to go
cd \Workerservice2\WorkerService2
docker build .
But I get your error message.
=> ERROR [build 3/7] COPY [WorkerService2/WorkerService2.csproj, WorkerService2/] 0.0s
------
> [build 3/7] COPY [WorkerService2/WorkerService2.csproj, WorkerService2/]:
------
failed to compute cache key: "/WorkerService2/WorkerService2.csproj" not found: not found
Instead, go to the parent directory, with the .sln file and use the docker -f option to specify the Dockerfile to use in the subfolder:
cd \Workerservice2
docker build -f WorkerService2\Dockerfile --force-rm -t worker2/try7 .
docker run -it worker2/try7
Edit (Thanks Mike Loux, tblev & Goku):
Note the final dot on the docker build command.
For docker the final part of the command is the location of the files that Docker will work with. Usually this is the folder with the Dockerfile in, but that's what's different about how VS does it. In this case the dockerfile is specified with the -f. Any paths (such as with the COPY instruction in the dockerfile) are relative to the location specified. The . means "current directory", which in my example is \WorkerService2.
I got to this stage by inspecting the output of the build process, with verbosity set to Detailed.
If you choose Tools / Options / Projects and Solutions / Build and Run you can adjust the build output verbosity, I made mine Detailed.
Edit #2 I think I've worked out why Visual Studio does it this way.
It allows the project references in the same solution to be copied in.
If it was set up to do docker build from the project folder, docker would not be able to COPY any of the other projects in the solution in. But the way this is set up, with current directory being the solution folder, you can copy referenced projects (subfolders) into your docker build process.
I had the same issue, I set the Docker environment to Windows in when adding Docker support. Even running in Visual Studio threw error to that. I changed the environment to Linux as my Docker is running in the Windows Subsystem for Linux (WSL).
Then I moved back to the terminal to run the commands.
I was able to resolve this by moving to the Solutions folder (Root folder).
And I did docker build like this:
docker build -t containername/tag -f ProjectFolder/Dockerfile .
Then I did docker run:
docker run containername/tag
Asking for a directory that does not exist throws this error.
In my case, I tried
> [stage-1 7/14] COPY /.ssh/id_rsa.pub /.ssh/:
------
failed to compute cache key: "/.ssh/id_rsa.pub" not found: not found
I had forgotten to add the /.ssh folder to the project directory. In your case you should check whether /client is really a subfolder of your Dockerfile build context.
The following command was failing with failed to compute cache key: not found:
docker build -t tag-name:v1.5.1 - <Dockerfile
Upon changing the command to the following it got fixed:
docker build -t tag-name:v1.5.1 -f Dockerfile .
In my case I found that docker build is case sensitive in directory name, so I was writing /bin/release/net5.0/publish in the COPY instruction and failed with the same error, I've just changed to /bin/Release/net5.0/publish and it worked
Error : failed to compute cache key: "src" not found: not found
in my case , folder/file excluded in .dockerignore
after resolving file from dockerignore able to create image.
In my case, I had something like this:
FROM mcr.microsoft.com/dotnet/aspnet:5.0
COPY bin/Release/net5.0/publish/ app/
WORKDIR /app
ENTRYPOINT ["dotnet", "MyApi.dll"]
And I finally realized that I had the bin folder in my .dockerignore file.
I had the same issue. In my case there was a wrong directory specified.
My Dockerfile was:
FROM mcr.microsoft.com/dotnet/sdk:5.0 AS publish
WORKDIR /app
COPY . .
RUN dotnet publish -c Release -o publish/web src/MyApp/MyApp.csproj
FROM mcr.microsoft.com/dotnet/aspnet:5.0
WORKDIR /app
COPY --from=publish publish/web .
EXPOSE 80
CMD ASPNETCORE_URLS=http://*:$PORT dotnet MyApp.dll
Then I realised that in the second build stage I am trying to copy project files from directory publish/web:
COPY --from=publish publish/web .
But as I specified workdir /app in the first stage, my files are located in that directory in image filesystem, so changing path from publish/web to app/publish/web resolved my issue.
So my final working Dockerfile is:
FROM mcr.microsoft.com/dotnet/sdk:5.0 AS publish
WORKDIR /app
COPY . .
RUN dotnet publish -c Release -o publish/web src/MyApp/MyApp.csproj
FROM mcr.microsoft.com/dotnet/aspnet:5.0
WORKDIR /app
COPY --from=publish app/publish/web .
EXPOSE 80
CMD ASPNETCORE_URLS=http://*:$PORT dotnet MyApp.dll
In my case there was a sneaky trailing whitespace in the file name.
------
> [3/3] COPY init.sh ./:
------
failed to compute cache key: "/init.sh" not found: not found
So the file was actually called "init.sh " instead of "init.sh".
I had a similar issues: Apparently, docker roots the file system during build to the specified build directory for security reasons. As a result, COPY and ADD cannot refer to arbitrary locations on the host file system. Additionally, there are other issues with syntax peculiarities. What eventually worked was the following:
COPY ./script_file.sh /
RUN /script_file.sh
I had faced the same issue.
The reason was the name of the DLL file in the Docker file is case sensitive.
FROM mcr.microsoft.com/dotnet/sdk:5.0 AS build
WORKDIR /src
COPY MyFirstMicroService.csproj .
RUN dotnet restore
COPY . .
RUN dotnet publish -c release -o /app
FROM mcr.microsoft.com/dotnet/aspnet:5.0
WORKDIR /app
COPY --from=build /app .
ENTRYPOINT ["dotnet", "**MyFirstMicroService.dll**"]
This .dll name should match your .csproj file.
This also happens when you don't provide the proper path to your COPY command input. The most important clue I had is that WORKDIR command opens a folder for the container, not in the windows explorer (so it doesn't affect the path you need to specify for the COPY command).
In my Case,
i was doing mistake in '/' and ''. Let me explain
Open your dockerfile (it should be named as dockerfile only, not DockerFile or Dockerfile).
You may have something like this-
FROM mcr.microsoft.com/dotnet/runtime:5.0
COPY bin\Release\net5.0\publish .
ENTRYPOINT ["dotnet", "HelloDocker.dll"]
Replace COPY bin\Release\net5.0\publish . to COPY bin/Release/net5.0/publish .
in my case, it was a wrong Build with PATH configuration e.g. Docker build context
Simple docker script
docker build .
where . is path to build context
Gradle+Docker
docker {
dependsOn build
dependsOn dockerFilesCopy
name "${project.name}:${project.version}"
files "build" // path to build context
}
Gradle+GitHub action
name: Docker build and push
on:
push:
branches: [ main ]
# ...
jobs:
build:
runs-on: ubuntu-latest
# ...
steps:
- name: Checkout
uses: actions/checkout#v2
# ...
- name: Build and export to Docker
uses: docker/build-push-action#v2
with:
# ...
file: src/main/docker/Dockerfile
context: ./build # path to build context
In my case, with Angular project, my project was in the folder called ex: My-Folder-Project and I was putting on Dockerfile COPY --from=publish app/dist/My-Folder-Project .
But of course the correct thing is put the "name" in your package.json like COPY --from=publish app/dist/name-in-package.json .
In my case I changed context, and path of Dockerfile within docker-compose.yml config:
services:
server:
# inheritance structru
extends:
file: ../../docker-compose.server.yml
# I recommend you to play with this paths
build:
context: ../../
dockerfile: ./apps/${APP_NAME}/Dockerfile
...
Context:
It's an application written in Kotlin and using Spring-boot with Maven.
Basically, I'd like to know if it makes sense what I'm doing.
Running mvn install then the target folder will be created with the corresponding jar file.
Therefore the Dockerfile will be just copying the jar file into the working directory of the container and run java -jar WHATEVER.jar.
Example of the simple Dockerfile
FROM openjdk:8-jre-alpine
COPY target/app-DEV-SNAPSHOT.jar .
EXPOSE 8089
CMD ["java", "-jar", "./app-DEV-SNAPSHOT.jar"]
But I'd say, makes much more sense to me to use the multi-stage building and in the first stage generate the jar file and in the second stage, execute it. I tried this second approach but I'm facing an issue with main class doesn't exist
Multi-stage Dockerfile:
FROM maven:3.5.2-jdk-8-alpine as BUILD
ENV APP_HOME=/usr/src/service
COPY ./src /usr/src/service
COPY pom.xml /usr/src/service
WORKDIR /usr/src/service
RUN mvn install
FROM openjdk:8-jre-alpine
COPY --from=BUILD /usr/src/service/target/app-DEV-SNAPSHOT.jar ./
EXPOSE 8080
CMD ["java", "-jar", "./app-DEV-SNAPSHOT.jar"]
Which one is the correct one?
You should use the multistage dockerfile. Reason being you want to have least dependency on the host system. When you run mvn on host you add dependency of mvn and in turn java.
My recommendation would be to use multistage docker to build in one stage and copy to another stage
I have a java application (jar file) that I want to be able to run from a docker image.
I have created a Dockerfile to create an image using centos as base and install java as such:
Dockerfile
FROM centos
RUN yum install -y java-1.7.0-openjdk
I ran docker build -t me/java7 after to obtain the image me/java7
however I am stuck at some dead ends.
How do I copy the jar file from the host into the image/container
I require 2 parameters. 1 is a file, which needs to be copied into a directory into the container at runtime. The other is a number which needs to be passed to the jar file in the java -jar command automatically when the user runs docker run with the parameters
Extra Notes:
The jar file is a local file. Not hosted anywhere accessible via wget or anything. The closest I have at the moment is a windows share containing it. I could also access the source from a git repository but that would involve compiling everything and installing maven and git on the image so I'd rather avoid that.
any help is much appreciated.
In the Dockerfile, add a local file using ADD, e g
ADD your-local.jar /some-container-location
You could use volumes to put a file in the container in runtime, e g
VOLUME /copy-into-this-dir
And then you run using
docker run -v=/location/of/file/locally:/copy-into-this-dir -t me/java7
You can use ENTRYPOINT and CMD to pass arguments, e g
ENTRYPOINT ["java", "-jar", "/whatever/your.jar"]
CMD [""]
And then again run using
docker run -v=/location/of/file/locally:/copy-into-this-dir -t me/java7 --myNumber 42
(Have a look at the Dockerfile documentation.)
Suppose your file structure is as follow :
DockerTest
└── Dockerfile
└── local.jar
Dockerfile content will be :
FROM centos
RUN yum install -y java-1.7.0-openjdk
EXPOSE 8080
ADD /local.jar fatJar.jar
ENTRYPOINT ["java","-jar","fatJar.jar"]
Use following command :
$ cd DockerTest
$ docker build -f Dockerfile -t demo .