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Wire Tap

Pattern	Wire tap publishes each incoming message unmodified to a secondary channel for inspection and analysis.
How Ballerina helps	Ballerina has a lightweight concurrency model with built-in syntax support. This helps to send messages to a secondary channel parallelly without blocking the main channel.

Wire TapMessage ChannelMessage Endpoint

import ballerina/http;

type SnowflakeRequest record {
    string statement;
    string timeout = "60";
    string database = "messageLog";
    string schema = "message";
    string role = "logger";
};

type StockResponse record {
    string ParentHandlingUnitUUID;
    string StockItemUUID;
    string EWMWarehouse;
    string HandlingUnitNumber;
    string ShelfLifeExpirationDate;
    string CountryOfOrigin;
};

type LogLevel "INFO"|"WARNING"|"ERROR";

final http:Client sapClient = check new ("http://api.sap.com.balmock.io");
final http:Client db = check new ("http://api.snowflake.com.balmock.io");

⋯


service /warehouse on new http:Listener(8080) {

    resource function get stock(string parentId, string productId) returns StockResponse|error {
        StockResponse result = check sapClient->/WarehousePhysicalStockProducts/[parentId]/[productId];
        worker w returns error? {
            check wiretap("stock", "INFO", result.toString());
        }
        return result;
    }
}

function wiretap(string tableName, LogLevel severity, string message) returns error? {
    SnowflakeRequest snowflakeRequest = {statement: string `insert into ${tableName} values (${message}, ${severity}))`};
    json _ = check db->/statements.post(snowflakeRequest);
}