new version for Code Engine (#5)

* version for Code Engine

* Db2 driver version

* Db2 driver version

* old CF branch

Dockerfile

@@ -0,0 +1,55 @@
+########
+# Python dependencies builder
+#
+# Full official Debian-based Python image
+FROM python:3.8 AS builder
+
+# Always set a working directory
+WORKDIR /app
+# Sets utf-8 encoding for Python et al
+ENV LANG=C.UTF-8
+ENV PYTHONDONTWRITEBYTECODE=1
+ENV PYTHONUNBUFFERED=1
+
+
+# Ensures that the python and pip executables used
+# in the image will be those from our virtualenv.
+ENV PATH="/venv/bin:$PATH"
+
+# Install OS package dependencies.
+# Do all of this in one RUN to limit final image size.
+RUN apt-get update && \
+    apt-get install -y --no-install-recommends \
+        build-essential && \
+        rm -rf /var/lib/apt/lists/*
+
+# Setup the virtualenv
+RUN python -m venv /venv
+
+# Install Python deps
+COPY requirements.txt ./
+RUN pip install --no-cache-dir -r requirements.txt
+
+
+# Actual container
+#
+#
+FROM python:3.8-slim AS app
+
+# Extra python env
+ENV PATH="/venv/bin:$PATH"
+
+WORKDIR /app
+EXPOSE 8080
+
+# copy in Python environment
+COPY --from=builder /venv /venv
+
+RUN apt-get update && \
+    apt-get install -y --no-install-recommends \
+        libxml2 && \
+    rm -rf /var/lib/apt/lists/*
+
+# copy in the rest of the app
+COPY ./ ./
+ENTRYPOINT ["gunicorn", "--bind", "0.0.0.0:8080","worldcities:app"]

README.md

@@ -1,10 +1,17 @@
+**Note**: A former version of the tutorial deployed the app to Cloud Foundry Public on IBM Cloud. You can find the material in the [branch **cloudfoundry**](https://github.com/IBM-Cloud/cloud-sql-database/tree/cloudfoundry).
+
 # IBM Cloud SQL Database
 This tutorial shows how to provision a SQL (relational) database service, create a table and load a larger data set, city information into the database. Thereafter, we deploy a web app "worldcities" to make use of that data and show how to access the cloud database. The app is written in Python using the Flask framework.
 
 This tutorial is part of [IBM Cloud tutorials](https://cloud.ibm.com/docs/tutorials?topic=solution-tutorials-tutorials) and discussed as [SQL Database for Cloud Data](https://cloud.ibm.com/docs/solution-tutorials?topic=solution-tutorials-sql-database).
 
 # Up and running in few steps
 To get this SQL database-backed app up and running only few steps and about 10 minutes are needed. Please follow the steps outlined in the IBM Cloud tutorial.
-
+
+# Local testing
+
+- Install the requirements to run Python directly or build and run the container image.
+- Set the environment variable **DASHDB_SSLDSN** to the value obtained from the Db2 Warehouse credentials for the key **ssldsn**.
+
 # Feedback
-If you have feedback on the code or the related tutorial, please either open an issue on this repository or leave documentation feedback at the above mentioned tutorial.
+If you have feedback on the code or the related tutorial, please open an issue on this repository.

requirements.txt

@@ -1,2 +1,4 @@
-Flask
-ibm_db
+Flask==2.0.3
+gunicorn
+ibm_db == 3.1.2
+python-dotenv==0.15.0

templates/index.html

@@ -3,7 +3,7 @@
 {% block title %}World Cities{% endblock %}
 {% block content %}
 <h1>Hello Cities of the World!</h1>
-<p>This app is named "{{ app["application_name"] }}". You can search for information on cities with a population over 1000. Use the local name.
+<p>You can search for information on cities with a population over 1000. Use the local name.
 As an alternative, you can directly access city information using "/city/name", e.g., <a href="/city/Friedrichshafen">/city/Friedrichshafen</a>.</p>
 <br>
 <p>

worldcities.py

@@ -1,4 +1,4 @@
-# (C) 2017 IBM
+# (C) 2017-2022 IBM
 # Author: Henrik Loeser
 #
 # Very short sample app used with Db2 Warehouse on Cloud to demonstrate
@@ -12,22 +12,27 @@
 import json
 import ibm_db
 
+# for loading .env
+from dotenv import load_dotenv
+
+# load environment
+load_dotenv()
+
 app = Flask(__name__)
 
 # get service information if on IBM Cloud Platform
-if 'VCAP_SERVICES' in os.environ:
-    db2info = json.loads(os.environ['VCAP_SERVICES'])['dashDB'][0]
-    db2cred = db2info["credentials"]
-    appenv = json.loads(os.environ['VCAP_APPLICATION'])
+if 'DASHDB_SSLDSN' in os.environ:
+    db2cred = os.getenv('DASHDB_SSLDSN')
 else:
-    raise ValueError('Expected cloud environment')
+    # log error, but continue - it might be before service binding
+    app.logger.error('No Db2 credentials configured.')
 
 # handle database request and query city information
 def city(name=None):
     # connect to DB2
     rows=[]
     try:
-      db2conn = ibm_db.connect(db2cred['ssldsn'], "","")
+      db2conn = ibm_db.connect(db2cred, "","")
       if db2conn:
           # we have a Db2 connection, query the database
           sql="select * from cities where name=? order by population desc"
@@ -55,7 +60,7 @@ def city(name=None):
 # main page to dump some environment information
 @app.route('/')
 def index():
-   return render_template('index.html', app=appenv)
+   return render_template('index.html')
 
 # for testing purposes - use name in URI
 @app.route('/hello/<name>')