feat(docker): Adding Dockerfile

docker/.gitkeep

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+

docker/Dockerfile

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+FROM golang:alpine as build
+
+# Install git.
+# Git is required for fetching the dependencies.
+RUN apk update && apk add --no-cache git
+
+# Create appuser.
+ENV USER=appuser
+ENV UID=10001 
+# See https://stackoverflow.com/a/55757473/12429735RUN 
+RUN adduser \    
+    --disabled-password \    
+    --gecos "" \    
+    --home "/nonexistent" \    
+    --shell "/sbin/nologin" \    
+    --no-create-home \    
+    --uid "${UID}" \    
+    "${USER}"
+
+WORKDIR /app
+COPY go.mod go.sum ./
+RUN go mod download
+
+COPY . .
+RUN go get -d -v 
+RUN GOOS=linux go build -ldflags="-w -s" -o /app/howto 
+
+
+
+FROM scratch 
+
+ARG OPENAI_API_KEY
+ENV OPENAI_API_KEY=${OPENAI_API_KEY} 
+
+# To allow TLS requests to OpenAI
+COPY --from=build /etc/ssl/certs/ca-certificates.crt /etc/ssl/certs/ca-certificates.crt
+
+# Import the user and group files from the builder.
+COPY --from=build /etc/passwd /etc/passwd
+COPY --from=build /etc/group /etc/group
+
+WORKDIR /app
+COPY --from=build /app/howto /app/howto
+
+# Use an unprivileged user.
+USER appuser:appuser
+
+ENTRYPOINT ["/app/howto"] 

docker/README.md

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+# Overview
+
+Run howto app in docker/podman container
+
+# Set up on shell
+
+## One time set up
+```bash
+./build.sh
+
+# Set API key
+## Could be set also in ~/.bashrc file or similar
+read -s OPENAI_API_KEY ; echo "export OPENAI_API_KEY=$OPENAI_API_KEY" >> <some_rc_file_loaded_at_shell>
+
+# Set alias 
+echo "alias howto=\"$(realpath)/run.sh\"" >> ~/.bashrc
+```
+
+# Usage
+
+```bash
+./run.sh "tar a file"
+
+# Or with alias
+howto "tar a file"
+```
+
+# Security hardening
+
+Image runs:
+- without (almost) any other filesystem files than binary itself (FROM scratch) 
+- with non-root user
+
+And provided run.sh script runs it with readonly container filesystem

docker/build.sh

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+#!/bin/bash
+
+# Execute from root of repo
+cd "$(git rev-parse --show-toplevel)"
+docker build -f docker/Dockerfile -t sandbox-howto .

docker/run.sh

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+#!/bin/bash
+
+CONFIG_DIR="$HOME/.howto/config"
+docker run --read-only -v "$CONFIG_DIR:/nonexistent:rw" -e OPENAI_API_KEY=$OPENAI_API_KEY sandbox-howto $1