docker can't build because of alpine error

Question

Hi I am trying build a docker and Docker file looks like this.

FROM alpine

LABEL description "Nginx + uWSGI + Flask based on Alpine Linux and managed by Supervisord"

# Copy python requirements file
COPY requirements.txt /tmp/requirements.txt

RUN apk add --no-cache \
    python3 \
    bash \
    nginx \
    uwsgi \
    uwsgi-python3 \
    supervisor && \
    python3 -m ensurepip && \
    rm -r /usr/lib/python*/ensurepip && \
    pip3 install --upgrade pip setuptools && \
    pip3 install -r /tmp/requirements.txt && \
    rm /etc/nginx/conf.d/default.conf && \
    rm -r /root/.cache

# Copy the Nginx global conf
COPY nginx.conf /etc/nginx/
# Copy the Flask Nginx site conf
COPY flask-site-nginx.conf /etc/nginx/conf.d/
# Copy the base uWSGI ini file to enable default dynamic uwsgi process number
COPY uwsgi.ini /etc/uwsgi/
# Custom Supervisord config
COPY supervisord.conf /etc/supervisord.conf

# Add demo app
COPY ./app /app
WORKDIR /app

CMD ["/usr/bin/supervisord"]

Errors looks like

Sending build context to Docker daemon  250.9kB
Step 1/11 : FROM alpine
 ---> 196d12cf6ab1
Step 2/11 : LABEL description "Nginx + uWSGI + Flask based on Alpine Linux and managed by Supervisord"
 ---> Using cache
 ---> d8d38c761b8d
Step 3/11 : COPY requirements.txt /tmp/requirements.txt
 ---> Using cache
 ---> cb29eb34ca46
Step 4/11 : RUN apk add --no-cache     python3     bash     nginx     uwsgi     uwsgi-python3     supervisor &&     python3 -m ensurepip &&     rm -r /usr/lib/python*/ensurepip &&     pip3 install --upgrade pip setuptools &&     pip3 install -r /tmp/requirements.txt &&     rm /etc/nginx/conf.d/default.conf &&     rm -r /root/.cache
 ---> Running in 3d568d2620dd
fetch http://dl-cdn.alpinelinux.org/alpine/v3.8/main/x86_64/APKINDEX.tar.gz
WARNING: Ignoring http://dl-cdn.alpinelinux.org/alpine/v3.8/main/x86_64/APKINDEX.tar.gz: could not connect to server (check repositories file)
fetch http://dl-cdn.alpinelinux.org/alpine/v3.8/community/x86_64/APKINDEX.tar.gz
WARNING: Ignoring http://dl-cdn.alpinelinux.org/alpine/v3.8/community/x86_64/APKINDEX.tar.gz: could not connect to server (check repositories file)
ERROR: unsatisfiable constraints:
  bash (missing):
    required by: world[bash]
  nginx (missing):
    required by: world[nginx]
  python3 (missing):
    required by: world[python3]
  supervisor (missing):
    required by: world[supervisor]
  uwsgi (missing):
    required by: world[uwsgi]
  uwsgi-python3 (missing):
    required by: world[uwsgi-python3]
The command '/bin/sh -c apk add --no-cache     python3     bash     nginx     uwsgi     uwsgi-python3     supervisor &&     python3 -m ensurepip &&     rm -r /usr/lib/python*/ensurepip &&     pip3 install --upgrade pip setuptools &&     pip3 install -r /tmp/requirements.txt &&     rm /etc/nginx/conf.d/default.conf &&     rm -r /root/.cache' returned a non-zero code: 6

A month ago it was building fine. Because of the limited knowledge in Docker i couldn't to figure what's causing the error. A quick google search has resulted in these two links: link1 link2 But none of them were working.

Answer 1

Build docker with flag "--network host" solved the issue. Here is the link.