So I am learning out docker for the first time and was wondering if I am doing this in the correct format for my flask app, as a lot of documentation online for the WOKRDIR command is changing dir into "/app" however my main file to run the app is run.py which would be the same directory as the actual docker file. However, WORKDIR doesn't let me do "WORKDIR ." to use the current DIR.
Can someone clarify if I have my docker file set up correctly?
(I also plan to host this on Heroku if that matters)
File structure
Docker file
# start by pulling the python image
FROM python:3.8-alpine
# copy the requirements file into the image
COPY ./requirements.txt /requirements.txt
# Don't need to switch working directory
# WORKDIR
# install the dependencies and packages in the requirements file
RUN pip install -r requirements.txt
# copy every content from the local file to the image
COPY . /app
# configure the container to run in an executed manner
ENTRYPOINT [ "python" ]
CMD ["run.py" ]
Related
This question is asked before yet After reviewing the answers I am still not able to copy the solution.
I am still new to docker and after watching tutorials and following articles I was able to create a Dockerfile for an existing GitHub repository.
I started by using the nearest available image as a base then adding what I need.
from what I read the problem is in WORKDIR and CMD commands
This is error message:
python: can't open file 'save_model.py': [Errno 2] No such file or directory*
This is my Dockerfile:
# syntax=docker/dockerfile:1
FROM tensorflow/serving:2.3.0-rc0-devel-gpu
WORKDIR app
COPY requirements-gpu.txt .
# install dependencies
RUN pip install -r requirements-gpu.txt
# copy the content of the local src directory to the working directory
COPY /home/pc/Desktop/yolo4_deep .
# command to run on container start
CMD ["python","./app/save_model.py","./app/object_tracker.py" ]
src
save_model.py
object_tracker.py
...
requirements.txt
Dockerfile
I tried WORKDIR command to set the absolute path: WORKDIR /home/pc/Desktop/yolo4_Deep_sort_nojupitor the result was Same Error.
I see multiple issues in your Dockerfile.
COPY /home/pc/Desktop/yolo4_deep .
The COPY command copies files from your local machine to the container. The path on your local machine must be path relative to your build context. The build context is the path you pass in when you run docker build . — in this case the . (the current directory) is the build context. Also the local machine path can only reference files located under the build context — i.e. paths containing .. (parent directory) or / (root directory) are not allowed.
WORKDIR app
WORKDIR sets the path inside the container not on your local machine. So WORKDIR /app means that all commands — RUN, CMD, ENTRYPOINT — will be executed from the /app directory.
CMD ["python","./app/save_model.py","./app/object_tracker.py" ]
As mentioned above WORKDIR /app causes all operations to be executed from the /app directory. So ./app/save_model.py is actually translated as /app/app/save_model.py.
Thanks for help Everyone.
As I mentioned earlier I'm beginner in the docker world. I solved the issue by editing the copy command.
# syntax=docker/dockerfile:1
FROM tensorflow/serving:2.3.0-rc0-devel-gpu
WORKDIR /home/pc/Desktop/yolo4_deep
COPY requirements-gpu.txt .
# install dependencies
RUN pip install -r requirements-gpu.txt
# copy the content of the local src directory to the working directory
COPY src/ .
# command to run on container start
ENTRYPOINT ["./start.sh"]
My directory is:
-Dockerfile
app/
-main.go
media/
/css
/html
/img
/svg
Inside the html folder, I have subfolders to organise my HTML files, so the path to the HTML files is media/html/*/*.html
And I have my Dockerfile as follows:
FROM golang:alpine
# Set necessary environmet variables needed for our image
ENV GO111MODULE=on \
CGO_ENABLED=0 \
GOOS=linux \
GOARCH=amd64
# Copy the code into the container
COPY media .
# Move to working directory /build
WORKDIR /build
# Copy the code from /app to the build folder into the container
COPY app .
# Configure the build (go.mod and go.sum are already copied with prior step)
RUN go mod download
# Build the application
RUN go build -o main .
WORKDIR /app
# Copy binary from build to main folder
RUN cp /build/main .
# Export necessary port
EXPOSE 8080
# Command to run when starting the container
CMD ["/app/main"]
and my main.go is:
package main
import (
"net/http"
"github.com/gin-gonic/gin"
)
func main() {
// We create the instance for Gin
r := gin.Default()
// Path to the static files. /static is rendered in the HTML and /media is the link to the path to the images, svg, css.. the static files
r.StaticFS("/static", http.Dir("../media"))
// Path to the HTML templates. * is a wildcard
r.LoadHTMLGlob("../media/html/*/*.html")
r.NoRoute(renderHome)
// This get executed when the users gets into our website in the home domain ("/")
r.GET("/", renderHome)
r.Run(":8080")
}
func renderHome(c *gin.Context) {
c.HTML(http.StatusOK, "my-html.html", gin.H{})
}
Problem is, I can run without problem my app in Golang with go run main.go, I can build the Docker image without problems, but on the moment to run a Docker container from the image, I got the error:
panic: html/template: pattern matches no files: ../media/html/*/*.html
The path is correct (since is also proven because I can run it in plain go) and it seems that Docker is not coping the files correctly, or at least not in the right directory. What is failing? The full simple project can be found here
media is a bad choice for a Docker folder, because a typical Linux container already has a /media folder.
But that's not the root cause.
The root cause is that COPY media . copies the contents of media folder to /. You probably want COPY media/ /media/ if you want to preserve the media folder itself (or use WORKDIR /media).
As a debug tool, you can run your container with a shell as entrypoint to "look around" it without starting your app:
docker build . -t test
docker run -it --rm test sh
/app # ls /media
cdrom floppy usb
/app # ls -R /html
/html:
website
/html/website:
my-html.html
As you can see your media/html folder is located at /html.
Some more notes:
It's a good idea to move go mod download to before COPY app so that the downloaded modules can be cached:
FROM golang:alpine
WORKDIR /build
COPY app/go.mod app/go.sum ./
RUN go mod download
COPY app .
RUN go build -o main .
WORKDIR /app
RUN cp /build/main .
COPY media /media/
EXPOSE 8080
CMD ["/app/main"]
As a next step you can look into two-stage builds to not depend on the golang image for running the compiled app (is only needed for building really).
I have a Dockerfile that explicitly defines which directores and files from the context directory are copied to the app directory. But regardless of this Docker tries to copy all files in the context directory.
The Dockerfile is in the context directory.
My test code and data files are in directories directly below the context directory. It attempts to copy everything in the context directory, not just the directories and files specified by my COPY commands. So I get a few hundred of these following ERROR messages, except specifying each and every file in every directory and sub directory:
ERRO[0043] Can't add file /home/david/gitlab/etl/testdata/test_s3_fetched.csv to tar: archive/tar: missed writing 12029507 bytes
...
ERRO[0043] Can't close tar writer: archive/tar: missed writing 12029507 bytes
Sending build context to Docker daemon 1.164GB
Error response from daemon: Error processing tar file(exit status 1): unexpected EOF
My reading of the reference is that it only copies all files and directories if there are no ADD or COPY directives.
I have tried with the following COPY patterns
COPY ./name/ /app/name
COPY name/ /app/name
COPY name /app/name
WORKDIR /app
COPY ./name/ /name
WORKDIR /app
COPY name/ /name
WORKDIR /app
COPY name /name
My Dockerfile:
FROM python3.7.3-alpine3.9
RUN apk update && apk upgrade && apk add bash
# Copy app
WORKDIR /app
COPY app /app
COPY configfiles /configfiles
COPY logs /logs/
COPY errorfiles /errorfiles
COPY shell /shell
COPY ./*.py .
WORKDIR ../
COPY requirements.txt /tmp/
RUN pip install -U pip && pip install -U sphinx && pip install -r /tmp/requirements.txt
EXPOSE 22 80 8887
I expect it to only copy my files without the errors associated with trying to copy files I have not specified in COPY commands. Because the Docker output scrolls off my terminal window due to aqll thew error messages I cannot see if it succeeded with my COPY commands.
All files at and below the build directory are coppied into the initial layer of the docker build context.
Consider using a .dockerignore file to exclude files and directories from the build.
Try to copy the files in the following manner-
# set working directory
WORKDIR /usr/src/app
# add and install requirements
COPY ./requirements.txt /usr/src/app/requirements.txt
RUN pip install -r requirements.txt
# add app
COPY ./errorfiles /usr/src/app
Also, you will have to make sure that your docker-compose.yml file is correctly built-
version: "3.6"
services:
users:
build:
context: ./app
dockerfile: Dockerfile
volumes:
- "./app:/usr/src/app"
Here, I'm assuming that your docker-compose.yml file is inside the parent directory of your app.
See if this works. :)
docker build Dockerfile .//running it correctly.
1.) I have mentioned in the comments each command will execute as written, Is that correct working of this Dockerfile?
2.)These commands will be used to make the image when I ran docker build, so
[ec2-user#ip-xx-xx-xx-xx ~]$cd /project/p1
[ec2-user#ip-xx-xx-xx-xx p1]$ls
Dockerfile a b c d
My Dockerfile consists of following commands.
Dockerfile
node 8.1.0 //puls the image from hub
RUN mkdir -p /etc/x/y //make directory in the host at path /etc/x/y
RUN mkdir /app //make directory in the host at path /app
COPY . /app //copy all the files that is
WORKDIR /app //cd /app; now the working directory will be /app for next commands i.e npm install.
RUN npm install
EXPOSE 3000 //what this will do?
Question 1: how to run docker build?
docker build Dockerfile . # am I running it correctly.
No, you run it with docker build . and docker will automatically look for the Dockerfile in the current directory. Or you use docker build -f Path_to_the_docker_file/DockerFile where you clearly specify the path to the DockerFile.
Question 2: Fixing errors and clarifying commands
There are few mistakes in the Dockerfile, check the edited comments:
# pulls the image from dockerhub : YES
# Needs to be preceeded with FROM
FROM node 8.1.0
# all directories are made inside the docker image
# make directory in the image at path /etc/x/y : YES
RUN mkdir -p /etc/x/y
# make directory in the image at path /app : YES
RUN mkdir /app
COPY . /app # copy all the files that is : YES
WORKDIR /app # cd /app; now the working directory will be /app for next commands i.e npm install. : YES
RUN npm install
EXPOSE 3000 # what this will do? => tells all docker instances of this image to listen on port 3000.
I've got a node_modules folder which is 120MB+ and I'm wondering if we can somehow only push the node_modules folder if it has changed?
This is what my docker file looks like at the moment:
FROM node:6.2.0
# Create app directory
RUN mkdir -p /usr/src/app
WORKDIR /usr/src/app
# Install app dependencies
COPY package.json /usr/src/app/
RUN npm install
# Bundle app source
COPY . /usr/src/app
CMD export NODE_ENV=production
EXPOSE 80:7000
# EXPOSE 7000
CMD [ "npm", "start" ]
So what I'm wanting to do is only push the node_modules folder if it has changed! I don't mind manually specifying when the node_modules folder has changed, whether I do this by passing a flag & using an if statement, I don't know?
Use case:
I only made changes to my application code and didn't add any new packages.
I added some packages and require the node_modules folder to be pushed.
Edit:
So I tried the following docker file which brought in some logic from
http://bitjudo.com/blog/2014/03/13/building-efficient-dockerfiles-node-dot-js/
When I run docker built -t <name> . with the below Dockerfile & then gcloud docker -- push <url> it will still try push my whole directory to the registry?!
FROM node:6.2.0
ADD package.json /tmp/package.json
RUN cd /tmp && npm install
# Create app directory
RUN mkdir -p /usr/src/app && cp -a /tmp/node_modules /usr/src/app/
WORKDIR /usr/src/app
# Install app dependencies
# COPY package.json /usr/src/app/
# RUN npm install
# Bundle app source
ADD . /usr/src/app
CMD export NODE_ENV=production
EXPOSE 80:7000
# EXPOSE 7000
CMD [ "npm", "start" ]
Output from running gcloud docker -- push etc...:
f614bb7269f3: Pushed
658140f06d81: Layer already exists
be42b5584cbf: Layer already exists
d70c0d3ee1a2: Layer already exists
5f70bf18a086: Layer already exists
d0b030d94fc0: Layer already exists
42d0ce0ecf27: Layer already exists
6ec10d9b4afb: Layer already exists
a80b5871b282: Layer already exists
d2c5e3a8d3d3: Layer already exists
4dcab49015d4: Layer already exists
f614bb7269f3 is always being pushed and I can't figure out why (new to Docker). It's trying to push the whole directory which my app is in!?
Any ideas?
This blog post explains how to cache your dependencies in subsequent builds of your image by creating a layer that can be cached as long as the package.json file hasn't changes - http://bitjudo.com/blog/2014/03/13/building-efficient-dockerfiles-node-dot-js/
This is a link to the gist code snippet - https://gist.github.com/dweinstein/9468644
Worked wonders for our node app in my organization.