Use a sample FastAPI application for demo

README.md

@@ -23,6 +23,49 @@ $ curl k8s-test3e3d-apppubli-58f1d9adf4-5081003c9ca93235.elb.us-east-2.amazonaws
 {"message":"Webpage viewed 1 time(s)"}
 ```
 
+Note: This example uses the auto-generated user, which is limited to the default database, via the following env variables:
+
+```
+containers: {
+  app: {
+    build: {
+      context: "."
+      target: "dev"
+    }
+    consumes: ["db"]
+    ports: publish: "8000/http"
+    env: {
+      DB_HOST: "@{service.db.address}"
+      DB_PORT: "@{service.db.port.27017}"
+      DB_NAME: "@{service.db.data.dbName}"               <--
+      DB_USER: "@{service.db.secrets.user.username}"     <--
+      DB_PASS: "@{service.db.secrets.user.password}"     <--
+    }
+  }
+}
+```
+
+We could have used the admin user instead, this one does not have any limitation on the whole mongodb instance.
+
+```
+containers: {
+  app: {
+    build: {
+      context: "."
+      target: "dev"
+    }
+    consumes: ["db"]
+    ports: publish: "8000/http"
+    env: {
+      DB_HOST: "@{service.db.address}"
+      DB_PORT: "@{service.db.port.27017}"
+      DB_USER: "@{service.db.secrets.admin.username}"   <--
+      DB_PASS: "@{service.db.secrets.admin.password}"   <--
+    }
+  }
+}
+```
+
 ## Parameters
 
 When the single *MongoDB* instance is created, a default user is created, this one only has admin access against a given database. By default:

examples/Acornfile

@@ -4,27 +4,18 @@ services: db: {
 
 containers: {
   app: {
-    image: "mongo:6.0.5"
-    entrypoint: ["/bin/sh", "-c", "/check-db.sh"]
-    env: {
+    build: {
+      context: "."
+      target: "dev"
+    }
+	  consumes: ["db"]
+    ports: publish: "8000/http"
+	  env: {
       DB_HOST: "@{service.db.address}"
-      DB_NAME: "@{service.db.data.dbName}"
-      DB_USER: "@{service.db.secrets.user.username}"
-      DB_PASS: "@{service.db.secrets.user.password}"
+		  DB_PORT: "@{service.db.port.27017}"
+		  DB_NAME: "@{service.db.data.dbName}"
+		  DB_USER: "@{service.db.secrets.user.username}"
+		  DB_PASS: "@{service.db.secrets.user.password}"
     }
-    files: "/check-db.sh": """
-      echo "Will try to connect to cluster"
-      while true; do
-        echo "=> testing DB connection..."
-        mongosh --host ${DB_HOST} -u ${DB_USER} -p ${DB_PASS} --eval "db.adminCommand('ping')" 
-        if [ $? -eq 0 ]; then
-          break
-        else
-          sleep 5
-        fi
-      done
-      echo "connected to the DB"
-      sleep 3600
-    """
   }
 }

examples/Dockerfile

@@ -0,0 +1,15 @@
+FROM python:3.9 as base
+WORKDIR /app
+
+FROM base as build
+COPY requirements.txt requirements.txt
+RUN pip install --no-cache-dir --upgrade -r requirements.txt
+COPY . .
+
+FROM build as dev
+EXPOSE 8000
+CMD ["uvicorn", "main:app", "--reload", "--host", "0.0.0.0", "--port", "8000", "--proxy-headers"]
+
+FROM build as production
+EXPOSE 8000
+CMD ["uvicorn", "main:app", "--host", "0.0.0.0", "--port", "8000"]

examples/main.py

@@ -0,0 +1,33 @@
+import os
+from fastapi import FastAPI
+from pymongo import MongoClient
+
+app = FastAPI()
+
+DB_HOST = os.environ.get('DB_HOST')
+DB_PORT = os.environ.get('DB_PORT')
+DB_USER = os.environ.get('DB_USER')
+DB_PASS = os.environ.get('DB_PASS')
+DB_NAME = os.environ.get('DB_NAME')
+
+MONGO_URI = f"mongodb://{DB_USER}:{DB_PASS}@{DB_HOST}:{DB_PORT}/{DB_NAME}?authSource=admin"
+
+client = MongoClient(MONGO_URI)
+db = client[DB_NAME] 
+collection = db.hits_collection 
+
+@app.get('/')
+def hello():
+    # If the counter does not exist, we initialize it with a value of 0
+    counter_data = collection.find_one({"_id": "page_counter"})
+    if not counter_data:
+        collection.insert_one({"_id": "page_counter", "count": 0})
+        counter = 0
+    else:
+        counter = counter_data["count"]
+
+    # Increment the counter
+    collection.update_one({"_id": "page_counter"}, {"$inc": {"count": 1}})
+    counter += 1
+
+    return {"message": f"Webpage viewed {counter} time(s)"}

examples/requirements.txt

@@ -0,0 +1,3 @@
+fastapi == 0.101.0
+uvicorn[standard] == 0.23.2
+pymongo[srv]==3.12.0