Sentiment Analysis function for FaaS

Dockerfile

FROM python:2.7-alpine
RUN pip install textblob
RUN python -m textblob.download_corpora

ADD https://github.com/alexellis/faas/releases/download/0.5.1-alpha/fwatchdog /usr/bin
RUN chmod +x /usr/bin/fwatchdog

WORKDIR /root/

COPY handler.py .

ENV fprocess="python handler.py"

HEALTHCHECK --interval=1s CMD [ -e /tmp/.lock ] || exit 1

CMD ["fwatchdog"]

handler.py

import sys
import json
from textblob import TextBlob

def get_stdin():
    buf = ""
    for line in sys.stdin:
        buf = buf + line
    return buf

if(__name__ == "__main__"):
    st = get_stdin()
    blob = TextBlob(st)
    res = {
        "polarity": 0,
        "subjectivity": 0
    }

    for sentence in blob.sentences:
        res["subjectivity"] = res["subjectivity"] + sentence.sentiment.subjectivity
        res["polarity"] = res["polarity"] + sentence.sentiment.polarity

    total = len(blob.sentences)

    res["sentence_count"] = total
    res["polarity"] = res["polarity"] / total
    res["subjectivity"] = res["subjectivity"] / total

    print(json.dumps(res))