Add tor/proxy support for Docker builds, fix opensearch/init

The Dockerfile is now updated to include support for Tor configuration,
with a working torrc file included in the repo.

An issue with opensearch was fixed as well, which was uncovered during
testing and was simple enough to fix here. Likewise, DDG bang gen was
updated to only ever happen if the file didn't exist previously, as
testing with the file being regenerated every time was tedious.

Dockerfile

@@ -1,9 +1,13 @@
 FROM python:3.8-slim
 
 WORKDIR /usr/src/app
-RUN apt-get update && apt-get install -y build-essential libcurl4-openssl-dev libssl-dev tor
-RUN cat rc/torrc > /etc/tor/torrc
-RUN service tor start
+RUN apt-get update && apt-get install -y \
+    build-essential \
+    libcurl4-openssl-dev \
+    libssl-dev \
+    tor
+
+COPY rc/torrc /etc/tor/torrc
 COPY requirements.txt .
 RUN pip install --no-cache-dir -r requirements.txt
 
@@ -36,4 +40,4 @@ COPY . .
 
 EXPOSE $EXPOSE_PORT
 
-CMD ["./run"]
+CMD service tor start && ./run

README.md

@@ -25,6 +25,7 @@ Contents
 - No AMP links
 - No URL tracking tags (i.e. utm=%s)
 - No referrer header
+- Tor and HTTP/SOCKS proxy support
 - Autocomplete/search suggestions
 - POST request search and suggestion queries (when possible)
 - View images at full res without site redirect (currently mobile only)
@@ -35,7 +36,7 @@ Contents
 - Optional location-based searching (i.e. results near \<city\>)
 - Optional NoJS mode to disable all Javascript in results
 
-<sup>*If deployed to a remote server</sup>
+<sup>*If deployed to a remote server, or configured to send requests through a VPN, Tor, proxy, etc.</sup>
 
 ## Dependencies
 If using Heroku Quick Deploy, **you can skip this section**.

app/__init__.py

@@ -30,6 +30,7 @@ if not os.path.exists(app.config['SESSION_FILE_DIR']):
 # Generate DDG bang filter, and create path if it doesn't exist yet
 if not os.path.exists(app.config['BANG_PATH']):
     os.makedirs(app.config['BANG_PATH'])
+if not os.path.exists(app.config['BANG_FILE']):
     gen_bangs_json(app.config['BANG_FILE'])
 
 Session(app)

rc/torrc

@@ -1,4 +1,3 @@
-User tor
 DataDirectory /var/lib/tor
 ControlPort 9051
 CookieAuthentication 1

requirements.txt

@@ -25,7 +25,6 @@ PySocks==1.7.1
 pytest==5.4.1
 python-dateutil==2.8.1
 requests==2.23.0
-six==1.14.0
 soupsieve==1.9.5
 stem==1.8.0
 urllib3==1.25.9