Docker image for evaluating JavaScript

Author: usrbinsam

docker/Dockerfile

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+FROM alpine:latest
+LABEL maintainer="Sam Hoffman <sam@codewizardshq.com>"
+
+RUN apk --update add --no-cache python3 bash curl binutils libc-dev python3-dev gcc
+RUN pip3 install -U pip
+RUN pip3 install flask flask-cors pyduktape gunicorn
+
+RUN adduser -D -H webapp
+RUN mkdir -p "/var/www/flaskapp"
+
+# default Flask port
+EXPOSE 5000/tcp
+
+USER webapp
+
+COPY "start.sh" "/tmp/start.sh"
+COPY "app.py" "/var/www/flaskapp/app.py"
+
+ENTRYPOINT [ "/tmp/start.sh" ]

docker/app.py

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+import pyduktape
+from flask import Flask, jsonify, request
+from flask_cors import CORS
+
+app = Flask(__name__)
+CORS(app)
+
+
+@app.route("/js/eval", methods=["POST"])
+def js_eval():
+    """Eval some JavaScript using pyduktape"""
+
+    if not request.is_json:
+        return jsonify(error="payload must be JSON format"), 400
+
+    data = request.get_json()
+
+    try:
+        code = data["code"]
+    except KeyError:
+        return jsonify(error="missing 'code' parameter"), 400
+
+    ctx = pyduktape.DuktapeContext()
+
+    output = ""
+    error = ""
+
+    code += ";output"
+
+    try:
+        output = ctx.eval_js(code)
+    except Exception as e:
+        error = str(e)
+
+    return jsonify(output=output, error=error)

docker/start.sh

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+#!/bin/sh
+set -e
+cd "/var/www/flaskapp/"
+gunicorn -b 0.0.0.0:5000 app:app