Dockerfile and documentation (#104)

* Disabled Redis disc persistence and refactored integration test, fixes #95

* Added Dockerfile with documentation

Author: ibnesayeed

Dockerfile

@@ -0,0 +1,20 @@
+FROM ruby:2.3
+MAINTAINER Sawood Alam <https://github.com/ibnesayeed>
+
+ENV LANG C.UTF-8
+
+RUN apt update && apt install -y libgsl0-dev && rm -rf /var/lib/apt/lists/*
+
+RUN cd /tmp \
+    && wget http://download.redis.io/redis-stable.tar.gz \
+    && tar xvzf redis-stable.tar.gz \
+    && cd redis-stable \
+    && make && make install \
+    && cd /tmp && rm -rf redis-stable*
+
+WORKDIR /usr/src/app
+COPY . /usr/src/app
+RUN bundle install
+RUN gem install narray nmatrix gsl redis
+
+CMD redis-server --daemonize yes && rake

README.markdown

@@ -252,6 +252,56 @@ with more than just simple strings.
 * http://www.chadfowler.com/index.cgi/Computing/LatentSemanticIndexing.rdoc
 * http://en.wikipedia.org/wiki/Latent_semantic_analysis
 
+## Development
+
+To make changes in the gem locally:
+
+```bash
+$ git clone [email protected]:jekyll/classifier-reborn.git
+# Alternatively, fork the repo and clone your fork.
+$ cd classifier-reborn
+$ bundle install
+$ gem install redis
+$ rake              # To run tests.
+```
+
+Some tests should be skipped if the Redis server is not running on the development machine. To test all the test cases first [install Redis](https://redis.io/topics/quickstart) then:
+
+```bash
+$ redis-server --daemonize yes
+$ rake              # To run tests.
+$ rake bench        # To run benchmarks.
+# Kill the redis-server daemon when done
+```
+
+### Development using Docker
+
+If the [Docker](https://docs.docker.com/engine/installation/) is installed on the machine:
+
+```bash
+$ git clone [email protected]:jekyll/classifier-reborn.git
+# Alternatively, fork the repo and clone your fork.
+$ cd classifier-reborn
+
+$ docker run --rm -it -v "$PWD":/usr/src/app jekyll/classifier-reborn
+# This will run all tests.
+# This step should repeated each time a change in the code is made.
+```
+
+If the Gemfile or other dependencies change, a rebuild of the Docker image is needed:
+
+```bash
+$ docker build -t jekyll/classifier-reborn .
+```
+
+To run tasks other than test or other commands access Bash prompt of the container:
+
+```bash
+$ docker run --rm -it -v "$PWD":/usr/src/app classifier-reborn bash
+root@[container-id]:/usr/src/app# redis-server --daemonize yes
+root@[container-id]:/usr/src/app# rake              # To run tests.
+root@[container-id]:/usr/src/app# rake bench        # To run benchmarks.
+```
 
 ## Code of Conduct