mirror of
https://github.com/dockersamples/example-voting-app.git
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620c76c715
The reasoning of this is because port 5000 is, by default, used by an AirPlay receiver process on Macs. While this can be turned off, we'd like this app to work without needing to adjust default configurations on a machine.
66 lines
2.4 KiB
Markdown
66 lines
2.4 KiB
Markdown
# Example Voting App
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A simple distributed application running across multiple Docker containers.
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## Getting started
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Download [Docker Desktop](https://www.docker.com/products/docker-desktop) for Mac or Windows. [Docker Compose](https://docs.docker.com/compose) will be automatically installed. On Linux, make sure you have the latest version of [Compose](https://docs.docker.com/compose/install/).
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This solution uses Python, Node.js, .NET, with Redis for messaging and Postgres for storage.
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Run in this directory to build and run the app:
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```shell
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docker compose up
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```
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The `vote` app will be running at [http://localhost:8080](http://localhost:8080), and the `results` will be at [http://localhost:8081](http://localhost:8081).
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Alternately, if you want to run it on a [Docker Swarm](https://docs.docker.com/engine/swarm/), first make sure you have a swarm. If you don't, run:
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```shell
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docker swarm init
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```
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Once you have your swarm, in this directory run:
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```shell
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docker stack deploy --compose-file docker-stack.yml vote
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```
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## Run the app in Kubernetes
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The folder k8s-specifications contains the YAML specifications of the Voting App's services.
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Run the following command to create the deployments and services. Note it will create these resources in your current namespace (`default` if you haven't changed it.)
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```shell
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kubectl create -f k8s-specifications/
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```
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The `vote` web app is then available on port 31000 on each host of the cluster, the `result` web app is available on port 31001.
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To remove them, run:
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```shell
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kubectl delete -f k8s-specifications/
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```
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## Architecture
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* A front-end web app in [Python](/vote) which lets you vote between two options
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* A [Redis](https://hub.docker.com/_/redis/) which collects new votes
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* A [.NET](/worker/) worker which consumes votes and stores them in…
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* A [Postgres](https://hub.docker.com/_/postgres/) database backed by a Docker volume
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* A [Node.js](/result) web app which shows the results of the voting in real time
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## Notes
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The voting application only accepts one vote per client browser. It does not register additional votes if a vote has already been submitted from a client.
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This isn't an example of a properly architected perfectly designed distributed app... it's just a simple
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example of the various types of pieces and languages you might see (queues, persistent data, etc), and how to
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deal with them in Docker at a basic level.
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