Errors and safe user messages

"""Safe SDK error UX, Python3.9+ / official Python SDK1.0.0.
Run: python3 python.py (KDP_APP_ID, KDP_STATE_DIR, optional KDP_BASE_URL origin).
Self-test: python3 python.py --self-test < cases.json; real result model, no network.
Output: valid/message/action/request_id only; never raw payload, key or token.
"""
import json
import os
import re
import sys
from pathlib import Path
from license_sdk import LicenseClient
from license_sdk.models import LicenseResult

POLICY=json.loads(Path(__file__).with_name('policy.json').read_text())
def explain(result):
    # Check valid first. A feature helper alone is not an access check.
    entry={'message':'Your license is ready.','action':'continue'} if result.valid else POLICY['codes'].get(result.error_code,POLICY['fallback'])
    request_id=result.request_id if isinstance(result.request_id,str) and re.fullmatch(r'req_[a-f0-9]{24}',result.request_id) else None
    return {'valid':result.valid,'message':entry['message'],'action':entry['action'],'request_id':request_id}

def main():
    if sys.argv[1:]==['--self-test']:
        rows=json.load(sys.stdin)
        for row in rows:
            result=LicenseResult(valid=row['valid'],source='synthetic contract',error_code=row.get('code'),request_id=row.get('request_id'))
            print(json.dumps(explain(result)))
        return
    if len(sys.argv)!=1:raise ValueError('Unknown action')
    client=LicenseClient(product=os.environ['KDP_APP_ID'],environment='SANDBOX',
        base_url=os.getenv('KDP_BASE_URL','https://licensing.kdpika.com'),storage_dir=Path(os.environ['KDP_STATE_DIR']),prefer_keyring=False)
    result=client.check(force_online=False)
    print(json.dumps(explain(result)))

if __name__=='__main__':
    try:main()
    except Exception:
        print('The license check is unavailable. Check configuration or contact the software developer.',file=sys.stderr);sys.exit(2)

// Safe SDK error UX. Node18.20+, official JavaScript SDK1.0.0, trusted runtime only.
// Run: node javascript.mjs; KDP_APP_ID/KDP_STATE_DIR, optional KDP_BASE_URL site origin.
// --self-test reads synthetic cases from stdin and uses actual SDK result objects.
// Output: safe UX/request ID only; no raw payload, key or token.
import fs from 'node:fs';
import {LicenseClient,LicenseResult} from '@kdpika/license-sdk';
const policy=JSON.parse(fs.readFileSync(new URL('./policy.json',import.meta.url),'utf8'));
export function explain(result){
  const entry=result.valid?{message:'Your license is ready.',action:'continue'}:policy.codes[result.errorCode]||policy.fallback;
  const requestId=typeof result.requestId==='string'&&/^req_[a-f0-9]{24}$/.test(result.requestId)?result.requestId:null;
  return {valid:result.valid,message:entry.message,action:entry.action,request_id:requestId};
}
try {
  if(process.argv.slice(2).join(' ')==='--self-test'){
    const rows=JSON.parse(fs.readFileSync(0,'utf8'));
    for(const row of rows)console.log(JSON.stringify(explain(new LicenseResult({valid:row.valid,source:'synthetic contract',errorCode:row.code,requestId:row.request_id}))));
  }else{
    if(process.argv.length!==2)throw Error();
    const client=new LicenseClient({product:process.env.KDP_APP_ID,environment:'SANDBOX',baseUrl:process.env.KDP_BASE_URL||'https://licensing.kdpika.com',storageDir:process.env.KDP_STATE_DIR});
    console.log(JSON.stringify(explain(await client.check(false))));
  }
}catch{console.error('The license check is unavailable. Check configuration or contact the software developer.');process.exitCode=2;}

<?php
// Safe SDK error UX. PHP8.2+, official PHP SDK1.0.0 direct source.
// Run: php php.php; KDP_SDK_DIR/KDP_APP_ID/KDP_STATE_DIR and optional KDP_BASE_URL.
// --self-test reads synthetic cases from stdin; actual result model, no network.
// Output safe message/action/request_id only; never payload/key/token.
declare(strict_types=1);
try {
    $sdk=rtrim((string)getenv('KDP_SDK_DIR'),'/');
    require $sdk.'/src/LicenseResult.php';require $sdk.'/src/LicenseClient.php';
    $policy=json_decode((string)file_get_contents(__DIR__.'/policy.json'),true,64,JSON_THROW_ON_ERROR);
    function explain(KDPika\LicenseSdk\LicenseResult $result,array $policy):array {
        $entry=$result->valid?['message'=>'Your license is ready.','action'=>'continue']:($policy['codes'][$result->errorCode??'']??$policy['fallback']);
        $id=$result->requestId!==null&&preg_match('/^req_[a-f0-9]{24}$/D',$result->requestId)?$result->requestId:null;
        return ['valid'=>$result->valid,'message'=>$entry['message'],'action'=>$entry['action'],'request_id'=>$id];
    }
    if(($argv[1]??'')==='--self-test'&&$argc===2){
        foreach(json_decode((string)stream_get_contents(STDIN),true,64,JSON_THROW_ON_ERROR) as $row){
            $result=new KDPika\LicenseSdk\LicenseResult(valid:$row['valid'],source:'synthetic contract',errorCode:$row['code']??null,requestId:$row['request_id']??null);
            echo json_encode(explain($result,$policy),JSON_THROW_ON_ERROR).PHP_EOL;
        }
    }else{
        if($argc!==1)throw new RuntimeException('Unknown action');
        $client=new KDPika\LicenseSdk\LicenseClient(product:(string)getenv('KDP_APP_ID'),environment:'SANDBOX',baseUrl:getenv('KDP_BASE_URL')?:'https://licensing.kdpika.com',storageDir:(string)getenv('KDP_STATE_DIR'));
        echo json_encode(explain($client->check(false),$policy),JSON_THROW_ON_ERROR).PHP_EOL;
    }
}catch(Throwable){fwrite(STDERR,"The license check is unavailable. Check configuration or contact the software developer.\n");exit(2);}

// Safe SDK error UX. .NET7+, official C# SDK1.0.0 project/package reference.
// Run: dotnet run --project Errors.csproj; KDP_APP_ID/KDP_STATE_DIR, optional site origin KDP_BASE_URL.
// --self-test reads synthetic cases from stdin; actual SDK result model, no network.
// Output safe message/action/request_id only; never raw payload/key/token.
using System.Text.Json;
using System.Text.RegularExpressions;
using KDPika.LicenseSdk;
try
{
    using var policy=JsonDocument.Parse(File.ReadAllText(Path.Combine(AppContext.BaseDirectory,"policy.json")));
    object Explain(LicenseResult result)
    {
        var found=result.ErrorCode is not null&&policy.RootElement.GetProperty("codes").TryGetProperty(result.ErrorCode,out _);
        var entry=found?policy.RootElement.GetProperty("codes").GetProperty(result.ErrorCode!):policy.RootElement.GetProperty("fallback");
        var message=result.Valid?"Your license is ready.":entry.GetProperty("message").GetString();
        var action=result.Valid?"continue":entry.GetProperty("action").GetString();
        var id=result.RequestId is not null&&Regex.IsMatch(result.RequestId,"^req_[a-f0-9]{24}$")?result.RequestId:null;
        return new {valid=result.Valid,message,action,request_id=id};
    }
    if(args.Length==1&&args[0]=="--self-test")
    {
        using var rows=JsonDocument.Parse(Console.In.ReadToEnd());
        foreach(var row in rows.RootElement.EnumerateArray())
        {
            var result=new LicenseResult(row.GetProperty("valid").GetBoolean(),"synthetic contract",default,
                row.TryGetProperty("code",out var code)?code.GetString():null,
                RequestId:row.TryGetProperty("request_id",out var requestId)?requestId.GetString():null);
            Console.WriteLine(JsonSerializer.Serialize(Explain(result)));
        }
    }
    else
    {
        if(args.Length!=0)throw new Exception("Unknown action");
        var client=new LicenseClient(product:Environment.GetEnvironmentVariable("KDP_APP_ID")!,environment:"SANDBOX",
            baseUrl:Environment.GetEnvironmentVariable("KDP_BASE_URL")??"https://licensing.kdpika.com",
            storageDir:Environment.GetEnvironmentVariable("KDP_STATE_DIR"));
        Console.WriteLine(JsonSerializer.Serialize(Explain(await client.CheckAsync(false))));
    }
    return 0;
}
catch(Exception)
{
    Console.Error.WriteLine("The license check is unavailable. Check configuration or contact the software developer.");return 2;
}

<Project Sdk="Microsoft.NET.Sdk">
  <PropertyGroup>
    <OutputType>Exe</OutputType><TargetFramework>net7.0</TargetFramework>
    <ImplicitUsings>enable</ImplicitUsings><Nullable>enable</Nullable>
  </PropertyGroup>
  <ItemGroup>
    <ProjectReference Include="../../../../sdk/csharp/KDPika.LicenseSdk/KDPika.LicenseSdk.csproj" />
    <None Include="policy.json" CopyToOutputDirectory="PreserveNewest" />
  </ItemGroup>
</Project>