[[FEAT]] Add initial Docker/Containerfile

Having a local Containerfile allows anybody to build JSHint containers.
Better yet, it allows JSHint to supply official Docker containers for
users to use, rather then 'random containers from the internet'.

Note, that Containerfile is a modern way to signify agnostic Containers.
Internally, they are 100% pure Dockerfile's but for wider acceptance and
inclusion, Containerfile is the modern take.

The `--file Containerfile` argument might be needed for whichever
builder is used.

Signed-off-by: Olliver Schinagl <oliver@schinagl.nl>

.circleci/config.yml

@@ -55,6 +55,14 @@ jobs:
       - run:
           name: run tests
           command: npm run test-node
+  build-container:
+    machine:
+      image: ubuntu-2004:202111-02
+    steps:
+      - checkout
+      - run:
+          name: Build container
+          command: docker build --file 'Containerfile' --rm --tag 'jshint:latest' .
 
 workflows:
   orb-free-workflow:

.hadolint.yaml

@@ -0,0 +1,6 @@
+failure-threshold: "style"
+ignored:
+  - DL3007
+  - DL3008
+  - DL3013
+  - DL3018

Containerfile

@@ -0,0 +1,53 @@
+# SPDX-License-Identifier: MIT
+#
+# Copyright (C) 2022 Olliver Schinagl <oliver@schinagl.nl>
+
+FROM index.docker.io/library/alpine:latest AS builder
+
+WORKDIR /src
+
+COPY . /src/
+
+RUN apk add --no-cache \
+        git \
+        nodejs-current \
+        npm \
+    && \
+    npm ci \
+        --no-fund \
+        --production \
+        --verbose \
+    && \
+    mkdir -p '/jshint/node_modules/jshint' && \
+    cp -a 'node_modules/' '/jshint/' && \
+    cp -a 'bin/' 'data/' 'dist/' 'src/' 'package.json' \
+       '/jshint/node_modules/jshint' && \
+    npm ci \
+           --no-audit \
+           --no-fund \
+           --verbose \
+    && \
+    npm run pretest && \
+    npm run test-262 && \
+    npm run test-node && \
+    npm run test-website && \
+    node '/jshint/node_modules/jshint/bin/jshint' --version
+
+
+FROM index.docker.io/library/alpine:latest
+
+LABEL maintainer="Olliver Schinagl <oliver@schinagl.nl>"
+
+RUN apk add --no-cache \
+        nodejs-current \
+    && \
+    addgroup -S 'jshint' && \
+    adduser -D -G 'jshint' -h '/var/lib/jshint' -s '/bin/false' -S 'jshint' && \
+    ln -f -n -s '/usr/local/lib/node_modules/jshint/bin/jshint' '/usr/local/bin/jshint'
+
+COPY --from=builder "/jshint/node_modules/" "/usr/local/lib/node_modules"
+COPY "./containerfiles/container-entrypoint.sh" "/init"
+
+ENTRYPOINT [ "/init" ]
+
+USER 'jshint'

README.md

@@ -84,6 +84,44 @@ Engineers from these companies and projects use JSHint:
 
 And many more!
 
+## Using JSHint
+
+### Containers
+
+JSHint provides an official Container that can be used to run JSHint. To build
+a container using docker for example:
+
+```console
+$ docker build --file 'Containerfile' --rm --tag 'jshint:latest' .
+```
+
+Running the container is then as trivial as:
+
+```console
+$ docker run --rm --interactive --tty jshint:latest --help
+```
+
+To lint entire directories, a
+[docker volume mount](https://docs.docker.com/storage/volumes/) is needed,
+as otherwise the container does not have access to the code. In the following
+example the `pwd` utility is used, but other ways are of course possible.
+
+```console
+<path_to_lint> $ docker run --rm --interactive --tty --volume "$(pwd):$(pwd)" --workdir "$(pwd)" jshint:latest "$(pwd)"
+```
+
+To lint something quickly using stdin, `jshint` needs to be told to take its
+input from stdin via the `-` marker. The following example also shows how to
+pass additional options to the container:
+
+```console
+$ docker run --rm --interactive jshint:latest --show-non-errors - < file.js
+```
+
+> __Note:__ It is very common to see the `--tty` (the `t` in `-it`) flag for
+> interactive containers. However when using stdin, this is not correct.
+
+
 ## License
 
 JSHint is licensed under [the MIT Expat

containerfiles/container-entrypoint.sh

@@ -0,0 +1,22 @@
+#!/bin/sh
+# SPDX-License-Identifier: MIT
+#
+# Copyright (C) 2022 Olliver Schinagl <oliver@schinagl.nl>
+#
+# A beginning user should be able to docker run image bash (or sh) without
+# needing to learn about --entrypoint
+# https://github.com/docker-library/official-images#consistency
+
+set -eu
+
+# run command if it is not starting with a "-" and is an executable in PATH
+if [ "${#}" -le 0 ] || \
+   [ "${1#-}" != "${1}" ] || \
+   [ -d "${1}" ] || \
+   ! command -v "${1}" > '/dev/null' 2>&1; then
+	bin='jshint'
+fi
+
+exec ${bin:+${bin}} "${@}"
+
+exit 0