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Write a Redis subscriber plug-in

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package main

import (
    "github.com/extism/go-pdk"
)

//export hostPrintln
func hostPrintln(offset uint64) uint64

func Println(text string) {
    memoryText := pdk.AllocateString(text)
    hostPrintln(memoryText.Offset())
}

//export message
func message() uint64 {
    // read function argument from the memory
    input := pdk.Input()

    Println("👋 message: " + string(input))

    return 0
}

func main() {}

Build

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#!/bin/bash
tinygo build -scheduler=none --no-debug \
    -o redissub.wasm \
    -target wasi main.go

Run

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#!/bin/bash

./slingshot redis subscribe \
--wasm=./redissub.wasm \
--handler=message \
--uri=${REDIS_URI} \
--client-id=pubsubcli \
--channel=news

# Output:
🌍 redis URI      : *****
🌍 redis Client Id: pubsubcli
🚀 handler        : message
📦 wasm           : ./redissub.wasm
📺 channel        : news

Trigger the plugin

Connect to the Redis server: 

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#!/bin/bash
redis-cli -u  ${REDIS_URI}

Publish message(s): 

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redis.aivencloud.com:17170> PUBLISH news "Hello World"

Output

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👋 message: {"id":"pubsubcli","channel":"news","payload":"Hello World"}