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--- marc:linux:docker [2022/04/18 09:18] – [Additional Dockerfile instructions:] marcv
+++ marc:linux:docker [2022/04/19 10:03] (current) – [2 phase container building:] marcv
@@ Line 183: / Line 183: @@
 COPY $(PWD) .
-#copy everything from working directory (local) to working directory (container); defined as /usr/app!
+# copy everything from working directory (local) to working directory (container); defined as /usr/app!
 # Because we chose to copy the non-changing files before the RUN commands, the docker build will execute faster as
 # it does not need to include the RUN commands if we change other files
@@ Line 196: / Line 196: @@
 CMD ["prog1", "prog2"]
 </code>
+We can also define another Dockerfile to use for building a container:
+<code>
+docker build -f Dockerfile.dev
+</code>
+Another example of then starting the container:
+<code>
+docker run  -p 3000:3000 -v /app/node_modules -v $(pwd):/app ContainerID
+</code>
+In this example:
+  * docker run: run container
+  * -p 3000:3000: map local port 3000 to containerport 3000
+  * -v /app/node_modules: the /app/node_modules directory in the container is "carved in stone"/ do not change
+  * -v $(pwd):/app: copy all files from working dir inside container directory "/app" EXCEPT /app/node_modules!!!!
+The last parameter (-v $(pwd):/app is basically a volume mapping!
 ===== Docker Compose: =====
@@ Line 225: / Line 244: @@
     ports:                                       # ports to map
       - "8080:80"                                # map port 8080 on host to port 80 inside container
+    volumes:
+      - /app/node_volumes                        # directory "/app/node/modules" inside(!) volume does not change!
+      - .:/app                                   # copy all from local working directory to app directory inside
+                                                 # container (except /app/node_volumes!)
+    app3:
+      restart: never
+      build:
+        context: .                               # working directory
+        dockerfile: ./Dockerfile.dev             # define another file than default (Dockerfile)
+                                                 # it can also be a url to a git_directory
 </code>
@@ Line 274: / Line 303: @@
 {{:marc:linux:github_workflow.png?direct&800|}}
+===== 2 phase container building: =====
+By using a multiphase build we can:
+  - Use multiple images
+  - Reduce space by only copying the needed contents to the final container
+{{:marc:linux:multi_phase_build.png?direct&800|}}
+The __Dockerfile__ would look something like this:
+<code>
+FROM node:alpine as builder        # Using "as" we can tag this phase
+WORKDIR '/app'
+COPY package.json .
+RUN npm install
+COPY . .
+RUN npm run build                  # This creates the content we want to serve in the /app/build directory
+FROM nginx                         # Not using another tag; we differentiate the phases using "FROM"
+COPY --from=builder /app/build /usr/share/nginx/html
+</code>
+Notice we did not define the RUN command; this is not needed as this container will start nginx itself.