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Merge branch 'v1.7' into data-driven-components

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Mark Fussell 2022-06-17 13:35:06 -07:00 committed by GitHub
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39
daprdocs/content/en/developing-applications/building-blocks/pubsub/subscription-methods.md
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@ -3,7 +3,7 @@ type: docs
title: "Declarative and programmatic subscription methods"
linkTitle: "Subscription methods"
weight: 3000
description: "Learn more about the two methods by which Dapr allows you to subscribe to topics."
description: "Learn more about the methods by which Dapr allows you to subscribe to topics."
---
## Pub/sub API subscription methods
@ -13,7 +13,7 @@ Dapr applications can subscribe to published topics via two methods that support
| Subscription method | Description |
| ------------------- | ----------- |
| [**Declarative**]({{< ref "subscription-methods.md#declarative-subscriptions" >}}) | Subscription is defined in an **external file**. The declarative approach removes the Dapr dependency from your code and allows for existing applications to subscribe to topics, without having to change code. |
| [**Programmatic**]({{< ref "subscription-methods.md#programmatic-subscriptions" >}}) | Subscription is defined in the **user code**. The programmatic approach implements the subscription in your code. |
| [**Programmatic**]({{< ref "subscription-methods.md#programmatic-subscriptions" >}}) | Subscription is defined in the **application code**. The programmatic approach implements the subscription in your code. |
The examples below demonstrate pub/sub messaging between a `checkout` app and an `orderprocessing` app via the `orders` topic. The examples demonstrate the same Dapr pub/sub component used first declaratively, then programmatically.
@ -25,21 +25,22 @@ You can subscribe declaratively to a topic using an external component file. Thi
apiVersion: dapr.io/v1alpha1
kind: Subscription
metadata:
name: order_pub_sub
name: order
spec:
topic: orders
route: /checkout
pubsubname: order_pub_sub
pubsubname: pubsub
scopes:
- orderprocessing
- checkout
```
Notice, the pub/sub component `order_pub_sub` subscribes to topic `orders`.
- The `route` field tells Dapr to send all topic messages to the `/checkout` endpoint in the app.
- The `scopes` field enables this subscription for apps with IDs `orderprocessing` and `checkout`.
Here the subscription called `order`:
- Uses the pub/sub component called `pubsub` to subscribes to the topic called `orders`.
- Sets the `route` field to send all topic messages to the `/checkout` endpoint in the app.
- Sets `scopes` field to scope this subscription for access only by apps with IDs `orderprocessing` and `checkout`.
When running Dapr, call out the YAML component file path to point Dapr to the component.
When running Dapr, set the YAML component file path to point Dapr to the component.
{{< tabs ".NET" Java Python JavaScript Go Kubernetes>}}
@ -103,7 +104,7 @@ In your application code, subscribe to the topic specified in the Dapr pub/sub c
```csharp
//Subscribe to a topic
[Topic("order_pub_sub", "orders")]
[Topic("pubsub", "orders")]
[HttpPost("checkout")]
public void getCheckout([FromBody] int orderId)
{
@ -117,7 +118,7 @@ public void getCheckout([FromBody] int orderId)
```java
//Subscribe to a topic
@Topic(name = "orders", pubsubName = "order_pub_sub")
@Topic(name = "orders", pubsubName = "pubsub")
@PostMapping(path = "/checkout")
public Mono<Void> getCheckout(@RequestBody(required = false) CloudEvent<String> cloudEvent) {
return Mono.fromRunnable(() -> {
@ -136,7 +137,7 @@ public Mono<Void> getCheckout(@RequestBody(required = false) CloudEvent<String>
```python
#Subscribe to a topic
@app.subscribe(pubsub_name='order_pub_sub', topic='orders')
@app.subscribe(pubsub_name='pubsub', topic='orders')
def mytopic(event: v1.Event) -> None:
data = json.loads(event.Data())
logging.info('Subscriber received: ' + str(data))
@ -150,7 +151,7 @@ app.run(6002)
```javascript
//Subscribe to a topic
await server.pubsub.subscribe("order_pub_sub", "orders", async (orderId) => {
await server.pubsub.subscribe("pubsub", "orders", async (orderId) => {
console.log(`Subscriber received: ${JSON.stringify(orderId)}`)
});
await server.startServer();
@ -179,18 +180,18 @@ func eventHandler(ctx context.Context, e *common.TopicEvent) (retry bool, err er
{{< /tabs >}}
The `/checkout` endpoint matches the `route` defined in the subscriptions and this is where Dapr will send all topic messages to.
The `/checkout` endpoint matches the `route` defined in the subscriptions and this is where Dapr sends all topic messages to.
### Programmatic subscriptions
The programmatic approach returns the `routes` JSON structure within the code, unlike the declarative approach's `route` YAML structure. In the example below, we define the values found in the [declarative YAML subscription](#declarative-subscriptions) above within the application code.
The programmatic approach returns the `routes` JSON structure within the code, unlike the declarative approach's `route` YAML structure. In the example below, you define the values found in the [declarative YAML subscription](#declarative-subscriptions) above within the application code.
{{< tabs ".NET" Java Python JavaScript Go>}}
{{% codetab %}}
```csharp
[Topic("order_pub_sub", "checkout", event.type ==\"order\"")]
[Topic("pubsub", "checkout", event.type ==\"order\"")]
[HttpPost("orders")]
public async Task<ActionResult<Stock>> HandleCheckout(Checkout checkout, [FromServices] DaprClient daprClient)
{
@ -206,7 +207,7 @@ public async Task<ActionResult<Stock>> HandleCheckout(Checkout checkout, [FromSe
```java
private static final ObjectMapper OBJECT_MAPPER = new ObjectMapper();
@Topic(name = "checkout", pubsubName = "order_pub_sub")
@Topic(name = "checkout", pubsubName = "pubsub")
@PostMapping(path = "/orders")
public Mono<Void> handleMessage(@RequestBody(required = false) CloudEvent<String> cloudEvent) {
return Mono.fromRunnable(() -> {
@ -228,7 +229,7 @@ public Mono<Void> handleMessage(@RequestBody(required = false) CloudEvent<String
def subscribe():
subscriptions = [
{
'pubsubname': 'order_pub_sub',
'pubsubname': 'pubsub',
'topic': 'checkout',
'routes': {
'rules': [
@ -264,7 +265,7 @@ const port = 3000
app.get('/dapr/subscribe', (req, res) => {
res.json([
{
pubsubname: "order_pub_sub",
pubsubname: "pubsub",
topic: "checkout",
routes: {
rules: [
@ -325,7 +326,7 @@ type rule struct {
func configureSubscribeHandler(w http.ResponseWriter, _ *http.Request) {
t := []subscription{
{
PubsubName: "order_pub_sub",
PubsubName: "pubsub",
Topic: "checkout",
Routes: routes{
Rules: []rule{

27
daprdocs/content/en/developing-applications/building-blocks/state-management/howto-get-save-state.md
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@ -210,38 +210,39 @@ dapr run --app-id orderprocessing --app-port 6001 --dapr-http-port 3601 --dapr-g
{{% codetab %}}
```go
//dependencies
// dependencies
import (
"context"
"log"
"math/rand"
"time"
"strconv"
"time"
dapr "github.com/dapr/go-sdk/client"
)
//code
// code
func main() {
const STATE_STORE_NAME = "statestore"
rand.Seed(time.Now().UnixMicro())
for i := 0; i < 10; i++ {
time.Sleep(5000)
orderId := rand.Intn(1000-1) + 1
client, err := dapr.NewClient()
STATE_STORE_NAME := "statestore"
if err != nil {
panic(err)
}
defer client.Close()
ctx := context.Background()
//Using Dapr SDK to save and get state
if err := client.SaveState(ctx, STATE_STORE_NAME, "order_1", []byte(strconv.Itoa(orderId))); err != nil {
panic(err)
}
result, err := client.GetState(ctx, STATE_STORE_NAME, "order_2")
err = client.SaveState(ctx, STATE_STORE_NAME, "order_1", []byte(strconv.Itoa(orderId)), nil)
if err != nil {
panic(err)
}
log.Println("Result after get: ")
log.Println(result)
result, err := client.GetState(ctx, STATE_STORE_NAME, "order_1", nil)
if err != nil {
panic(err)
}
log.Println("Result after get:", string(result.Value))
time.Sleep(2 * time.Second)
}
}
```
@ -932,4 +933,4 @@ Invoke-RestMethod -Method Post -ContentType 'application/json' -Body '{"keys":["
- Read the full [State API reference]({{< ref state_api.md >}})
- Try one of the [Dapr SDKs]({{< ref sdks >}})
- Build a [stateful service]({{< ref howto-stateful-service.md >}})
- Build a [stateful service]({{< ref howto-stateful-service.md >}})