How to make all scripts not run when api response error? - laravel

Question

I use laravel and I use command laravel to synchronize my database
My command laravel to call api to synchronize like this :
<?php
namespace App\Console\Commands;
...
class MySynchronize extends Command
{
...
public function handle()
{
DB::statement("SET foreign_key_checks=0");
Vendor::truncate();
Location::truncate();
Item::truncate();
DB::statement("SET foreign_key_checks=1");
$requestContent = [
'auth' => ['Administrator', 'www.Secret.com', 'ntlm']
];
//call api vendor
try {
$client = new GuzzleHttpClient();
$apiRequest = $client->request('GET', "http://www.secret.com:1234/ODATA/ODataV4/Company('secret2018')/Vendor", $requestContent);
$jsonResponse = json_decode($apiRequest->getBody(), true);
$data = [];
foreach ($jsonResponse['value'] as $value) {
$created_at = Carbon::now();
$last_modified_at = Carbon::parse($value['Last_Date_Modified']);
$data[] = [
'id' => $value['Code'],
'name' => $value['Name'],
'last_modified_at' => $last_modified_at,
'created_at'=> $created_at,
'updated_at'=> $created_at
];
}
DB::table('vendors')->insert($data);
} catch (RequestException $re) {
// For handling exception.
}
//call api location
try {
$client = new GuzzleHttpClient();
$apiRequest = $client->request('GET', "http://www.secret.com:1234/ODATA/ODataV4/Company('secret2018')/Location", $requestContent);
$jsonResponse = json_decode($apiRequest->getBody(), true);
$data = [];
foreach ($jsonResponse['value'] as $value) {
$created_at = Carbon::now();
$data[] = [
'id' => $value['Code'],
'description' => $value['Name'],
'created_at'=> $created_at,
'updated_at'=> $created_at
];
}
DB::table('locations')->insert($data);
} catch (RequestException $re) {
// For handling exception.
}
//call api item
try {
$client = new GuzzleHttpClient();
$apiRequest = $client->request('GET', "http://www.secret.com:1234/ODATA/ODataV4/Company('secret2018')/Item", $requestContent);
$jsonResponse = json_decode($apiRequest->getBody(), true);
$data = [];
foreach ($jsonResponse['value'] as $value) {
$last_modified_at = Carbon::parse($value['Last_Date_Modified']);
$created_at = Carbon::now();
$data[] = [
'id' => $value['Code'],
'description' => $value['Description'],
'vendor_code' => $value['Vendor_Code']?$value['Vendor_Code']:null,
'last_modified_at' => $last_modified_at,
'created_at'=> $created_at,
'updated_at'=> $created_at
];
}
\DB::table('items')->insert($data);
} catch (RequestException $re) {
// For handling exception.
}
// send output
echo 'synchronize success';
}
}
First I delete all data in the table using truncate. If it is deleted then it will call the api for the insert process to table
My problem is when an error occurs on the api server. For example, server is died or another error. It makes the data in my database empty because I've run truncate
How do I improve the script so that when an error occurs on the api, truncate is not executed?
What is the best way? Do you use try catch in the try catch to handle it?

Answer 1

You should take a look at DB transactions: https://laravel.com/docs/5.7/database#database-transactions
If an exception is thrown within the transaction Closure, the transaction will automatically be rolled back.
So something like that could work:
public function handle()
{
DB::transaction(function () {
// your DB statements
try {
// external API calls
} catch (SomeException $e) {
// If for any reasons you want to catch the exception inside the closure
// (logging maybe?), make sure to rethrow it.
// Otherwise, Laravel won't know it needs to rollback the DB changes
throw $e;
}
});
}