mirror of https://github.com/dapr/quickstarts.git
83 lines
2.3 KiB
Markdown
83 lines
2.3 KiB
Markdown
# Dapr pub/sub
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In this quickstart, you'll create a publisher microservice and a subscriber microservice to demonstrate how Dapr enables a publish-subcribe pattern. The publisher will generate messages of a specific topic, while subscribers will listen for messages of specific topics. See [Why Pub-Sub](#why-pub-sub) to understand when this pattern might be a good choice for your software architecture.
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Visit [this](https://docs.dapr.io/developing-applications/building-blocks/pubsub/) link for more information about Dapr and Pub-Sub.
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> **Note:** This example leverages the Dapr client SDK. If you are looking for the example using only HTTP `requests` [click here](../http).
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This quickstart includes one publisher:
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- Node client message generator `checkout`
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And one subscriber:
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- Node subscriber `order-processor`
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### Run Node message publisher with Dapr
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1. Install dependencies:
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<!-- STEP
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name: Install Node dependencies
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-->
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```bash
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cd pub_sub/javascript/sdk/checkout
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npm install
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```
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<!-- END_STEP -->
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3. Run the Node publisher app with Dapr:
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<!-- STEP
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name: Run Node publisher
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expected_stdout_lines:
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- "You're up and running! Both Dapr and your app logs will appear here."
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- '== APP == Published data: {"orderId":2}'
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- '== APP == Published data: {"orderId":3}'
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- "Exited App successfully"
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- "Exited Dapr successfully"
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expected_stderr_lines:
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output_match_mode: substring
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background: true
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sleep: 10
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-->
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```bash
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dapr run --app-id checkout --components-path pub_sub/components/ --app-port 5001 -- node pub_sub/javascript/sdk/checkout/
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```
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<!-- END_STEP -->
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### Run Node message subscriber with Dapr
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1. Install dependencies:
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<!-- STEP
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name: Install Node dependencies
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-->
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```bash
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cd pub_sub/javascript/sdk/order-processor
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npm install
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```
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<!-- END_STEP -->
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3. Run the Node publisher app with Dapr:
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<!-- STEP
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name: Run Node publisher
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expected_stdout_lines:
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- "You're up and running! Both Dapr and your app logs will appear here."
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- '== APP == Subscriber received: {"orderId":6}'
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- "Exited Dapr successfully"
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- "Exited App successfully"
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expected_stderr_lines:
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output_match_mode: substring
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background: true
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sleep: 10
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-->
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```bash
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dapr run --app-id checkout --components-path pub_sub/components/ --app-port 5001 -- node pub_sub/javascript/sdk/order-processor/
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```
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<!-- END_STEP --> |