### Install KOA and Webhook Libraries

Source: https://help.lob.com/developer-docs/use-case-guides/ingesting-tracking-events-with-webhooks

Install the KOA framework and necessary libraries for handling webhooks.

```bash
npm install koa @types/koa
npm install @lob/webhook --save-dev
```

--------------------------------

### Initialize Lob SDK and Prepare Postcard Data in Java

Source: https://help.lob.com/developer-docs/use-case-guides/override-cancellation-window

This Java snippet shows the initial setup for using the Lob SDK, including API key initialization and preparing data structures for creating a postcard with a custom send date. This is the starting point for programmatic postcard creation in Java.

```java
package com.company.app;
 
 // HashMap for Java 8 and below
 // import java.util.HashMap;
 import java.util.Map;
 
 import com.lob.Lob;
 import com.lob.model.Address;
 import com.lob.model.Postcard;
 import com.lob.net.LobResponse;
 
 public class App
 {
    public static void main( String[] args )
    {
        Lob.init("<TEST_API_KEY>");
 

```

--------------------------------

### PHP Postcard Creation Setup

Source: https://help.lob.com/developer-docs/api-quickstart-guide

This PHP snippet initializes the Lob client with your API key. It serves as the starting point for creating postcards via the API in PHP. Replace '<TEST_API_KEY>' with your actual Lob Test API Key.

```php
<?php require __DIR__ . '/vendor/autoload.php';
 
$lob = new \Lob\Lob('<TEST_API_KEY');
 

```

--------------------------------

### Dynamic Documentation Query Example

Source: https://help.lob.com/developer-docs/postman-and-similar-tools

This example demonstrates how to query the documentation dynamically by appending an 'ask' parameter with a natural language question to the page URL.

```http
GET https://help.lob.com/developer-docs/postman-and-similar-tools.md?ask=<question>
```

--------------------------------

### Install Lob PHP SDK via Composer

Source: https://help.lob.com/developer-docs/sdks-and-libraries

Install the Lob PHP client using Composer. This is the recommended method for PHP projects.

```bash
composer require lob/lob-php
```

--------------------------------

### Install Lob Python Package

Source: https://help.lob.com/developer-docs/api-quickstart-guide

Install the Lob Python library from PyPI into your activated virtual environment.

```bash
pip install lob_python
```

--------------------------------

### GET Request to Query Documentation

Source: https://help.lob.com/developer-docs/use-case-guides/ingesting-tracking-events-with-webhooks

Use this GET request to ask specific questions about the documentation. The response includes direct answers and relevant excerpts.

```bash
GET https://help.lob.com/developer-docs/use-case-guides/ingesting-tracking-events-with-webhooks.md?ask=<question>
```

--------------------------------

### Install Lob Python SDK via Pip

Source: https://help.lob.com/developer-docs/sdks-and-libraries

Install the Lob Python SDK using pip. This is the standard method for Python projects.

```bash
pip install lob
```

--------------------------------

### Install Lob C#/.NET SDK

Source: https://help.lob.com/developer-docs/api-quickstart-guide

Add the Lob .NET SDK package to your C# project using the .NET CLI.

```bash
dotnet add package lob.dotnet
```

--------------------------------

### Create Postcard with Custom Send Date in PHP

Source: https://help.lob.com/developer-docs/use-case-guides/override-cancellation-window

This PHP example shows how to create a postcard and set a specific send date. Ensure you have the Lob PHP SDK installed via Composer and your API key is provided.

```php
<?php require __DIR__ . '/vendor/autoload.php';
 
$lob = new \Lob\Lob('<TEST_API_KEY');
 
$postcard = $lob->postcards()->create(array(
    "description"           => "First Postcard",
    "to[name]"              => "HARRY ZHANG",
    "to[address_line1]"     => "210 KING STREET",
    "to[address_city]"      => "SAN FRANCISCO",
    "to[address_state]"     => "CA",
    "to[address_zip]"       => "94107",
    "from[name]"            => "LEORE AVIDAR",
    "from[address_line1]"   => "210 KING STREET",
    "from[address_city]"    => "SAN FRANCISCO",
    "from[address_state]"   => "CA",
    "from[address_zip]"     => "94107",
    "front"                 => "<html style='padding: 1in; font-size: 50;'>Front HTML for {{name}}</html>",
    "back"                  => "<html style='padding: 1in; font-size: 20;'>Back HTML for {{name}}</html>",
    "merge_variables[name]" => "Harry",
    "send_date"             => "2022-07-01T14:00:00"
  ));
 print_r($postcard);
?>
```

--------------------------------

### Install Lob Ruby Gem Manually

Source: https://help.lob.com/developer-docs/sdks-and-libraries

Manually install the Lob Ruby gem using the 'gem install' command.

```bash
$ gem install lob
```

--------------------------------

### Install Lob TypeScript SDK via NPM

Source: https://help.lob.com/developer-docs/sdks-and-libraries

Install the Lob TypeScript SDK using NPM. This is the standard method for adding the SDK to your project.

```bash
$ npm i @lob/lob-typescript-sdk
```

--------------------------------

### Build and Install Lob TypeScript SDK from Source

Source: https://help.lob.com/developer-docs/sdks-and-libraries

Clone the Lob TypeScript SDK repository and install dependencies from the latest source. Use this for development or to access the newest features.

```bash
$ git clone git@github.com:lob/lob-typescript-sdk.git
$ npm install
```

--------------------------------

### Install React Address Autocomplete

Source: https://help.lob.com/developer-docs/sdks-and-libraries

Install the react-address-autocomplete package using npm. This component simplifies adding search autocomplete functionality using the Lob Autocomplete API.

```bash
npm install --save @lob/react-address-autocomplete
```

--------------------------------

### Install Lob Ruby Gem

Source: https://help.lob.com/developer-docs/api-quickstart-guide

Install the Lob Ruby gem using the RubyGems package manager.

```bash
gem install lob
```

--------------------------------

### Create Postcard with Metadata (PHP)

Source: https://help.lob.com/developer-docs/use-case-guides/mass-deletion-setup

This PHP example illustrates creating a postcard and setting metadata with a 'batch_id'. Ensure the Lob SDK is initialized with your API key.

```php
$lob = new \Lob\Lob('test_XXXXXX');

$postcard = $lob->postcards()->create(array(
    "to[name]" => "HARRY ZHANG",
    "to[address_line1]" => "210 KING STREET",
    "to[address_city]" => "SAN FRANCISCO",
    "to[address_state]" => "CA",
    "to[address_zip]" => "94107",
    "from[name]"            => "LEORE AVIDAR",
    "from[address_line1]" => "185 BERRY STREET",
    "from[address_line2]" => "SUITE 6100",
    "from[address_city]" => "SAN FRANCISCO",
    "from[address_state]" => "CA",
    "from[address_zip]" => "94107",
    "front" => "<html style='padding: 1in; font-size: 50;'>Front HTML</html>",
    "back" => "<html style='padding: 1in; font-size: 20;'>Back HTML</html>",
     "metadata[batch_id]" => "NEWYORK2022"
));
```

--------------------------------

### Create Postcard with Metadata (Python)

Source: https://help.lob.com/developer-docs/use-case-guides/mass-deletion-setup

This Python example demonstrates creating a postcard and assigning a 'batch_id' in the metadata. Ensure your Lob API key is set.

```python
import lob
lob.api_key = "test_XXXXXXXXX"

postcard = lob.Postcard.create(
   to_address = {
     "name": "HARRY ZHANG",
     "address_line1": "210 KING STREET",
     "address_city": "SAN FRANCISCO",
     "address_state": "CA",
     "address_zip": "94107"
   },
   from_address = {
     "name": "LEORE AVIDAR",
     "address_line1":  "185 BERRY STREET",
     "address_line2": "SUITE 6100",
     "address_city": "SAN FRANCISCO",
     "address_state": "CA",
     "address_zip": "94107",
     "address_country": "US"
     },
   front = "<html style='padding: 1in; font-size: 50;'>Front HTML</html>",
   back = "<html style='padding: 1in; font-size: 20;'>Back HTML</html>",
   metadata = {
        "batch_id": "NEWYORK2022"
   }
)
```

--------------------------------

### Querying Documentation with `ask` Parameter

Source: https://help.lob.com/developer-docs/use-case-guides/ncoa-responses

Perform an HTTP GET request to the current page URL with the `ask` query parameter to dynamically query the documentation. The question should be specific and self-contained.

```HTTP
GET https://help.lob.com/developer-docs/use-case-guides/ncoa-responses.md?ask=<question>
```

--------------------------------

### Install Latest LTS Node.js Version

Source: https://help.lob.com/developer-docs/api-quickstart-guide

Use this command to install the latest Long Term Support (LTS) release of Node.js via nvm.

```bash
nvm install --lts
```

--------------------------------

### Ask a Question via Documentation Index

Source: https://help.lob.com/developer-docs/%7B%7B%20revealButtonHref%20%7D%7D

Perform an HTTP GET request to the documentation index with the 'ask' parameter to get a direct answer to a specific question. The question should be self-contained and in natural language.

```http
GET https://help.lob.com/developer-docs/error-reference.md?ask=<question>
```

--------------------------------

### Query Documentation Dynamically

Source: https://help.lob.com/developer-docs/use-case-guides

Perform an HTTP GET request with the `ask` query parameter to retrieve specific information not explicitly present on a page. The question should be specific and in natural language.

```bash
GET https://help.lob.com/developer-docs/use-case-guides.md?ask=<question>
```

--------------------------------

### Query Documentation Dynamically

Source: https://help.lob.com/developer-docs

To get specific information not found directly on a page, make an HTTP GET request to the page URL with the 'ask' query parameter. The question should be clear and self-contained.

```HTTP
GET https://help.lob.com/developer-docs.md?ask=<question>
```

--------------------------------

### Query Documentation Dynamically

Source: https://help.lob.com/developer-docs/use-case-guides/override-cancellation-window

Use the 'ask' query parameter to get dynamic answers from the Lob documentation. This is useful when the answer is not explicitly present on the page, or you need clarification.

```http
GET https://help.lob.com/developer-docs/use-case-guides/override-cancellation-window.md?ask=<question>
```

--------------------------------

### Create a Postcard in Java

Source: https://help.lob.com/developer-docs/use-case-guides/mass-deletion-setup

This Java example shows how to create a postcard using the Lob Java SDK. Ensure you have initialized Lob with your API key before making the call.

```java
import java.util.Map;
import com.lob.Lob;
import com.lob.model.Address;
import com.lob.model.Postcard;
import com.lob.net.LobResponse;

public class App 
{
  public static void main( String[] args )
  {
     Lob.init("test_XXXXXXXX");

     try {
        LobResponse<Postcard> response = new Postcard.RequestBuilder()
         .setTo(
             new Address.RequestBuilder() 
                 .setName("HARRY ZHANG")
                 .setLine1("210 KING STREET")
                 .setCity("SAN FRANCISCO")
                 .setState("CA")
                 .setZip("94107")
             )
         .setFrom(
             new Address.RequestBuilder() 
                 .setName("LEORE AVIDAR")
                 .setLine1("210 KING STREET")
                 .setCity("SAN FRANCISCO")
                 .setState("CA")
                 .setZip("94107")
             )
         .setFront("<html style='padding: 1in; font-size: 50;'>Front HTML</html>")
         .setBack("<html style='padding: 1in; font-size: 20;'>Back HTML</html>")
         .create();
         /* Save to your database with the postcard.id and a unique group id */  

      } catch (Exception err) {
         System.out.println("Error on postcard creation: " + err);
      }
    }
 }
```

--------------------------------

### Add Node.js Type Definitions

Source: https://help.lob.com/developer-docs/use-case-guides/ingesting-tracking-events-with-webhooks

Install Node.js type definitions as a dev dependency to avoid TypeScript compiler errors.

```bash
npm install @types/node --save-dev
```

--------------------------------

### Include Composer Autoloader in PHP

Source: https://help.lob.com/developer-docs/sdks-and-libraries

After installing the Lob PHP client with Composer, require the autoloader to use the library.

```php
require 'vendor/autoload.php';
```

--------------------------------

### Create Postcard in PHP

Source: https://help.lob.com/developer-docs/api-quickstart-guide

Use this snippet to create a postcard with HTML front and back content. Ensure you have the Lob PHP client installed.

```php
$postcard = $lob->postcards()->create(array(
    "description" => "First Postcard",
    "to[name]"              => "HARRY ZHANG",
    "to[address_line1]"     => "210 KING STREET",
    "to[address_city]"      => "SAN FRANCISCO",
    "to[address_state]"     => "CA",
    "to[address_zip]"       => "94107",
    "from[name]"            => "LEORE AVIDAR",
    "from[address_line1]"   => "210 KING STREET",
    "from[address_city]"    => "SAN FRANCISCO",
    "from[address_state]"   => "CA",
    "from[address_zip]"     => "94107",
    "front"                 => "<html style='padding: 1in; font-size: 50;'>Front HTML for {{name}}</html>",
    "back"                  => "<html style='padding: 1in; font-size: 20;'>Back HTML for {{name}}</html>",
    "merge_variables[name]" => "Harry"
  ));
 print_r($postcard);
?>

```

--------------------------------

### Create Check with Address Details (Java - Partial)

Source: https://help.lob.com/developer-docs/use-case-guides/ncoa-responses

This Java snippet demonstrates the initial steps for creating a check with recipient and sender address details using the Lob Java SDK. Note: This is a partial example.

```java
import com.lob.Lob;
import com.lob.model.Address;
import com.lob.model.Check;
import com.lob.net.LobResponse;
public class App 
{
    public static void main( String[] args )
    {
        Lob.init("test_XXXXXXXX");
         try {
LobResponse<Check> response = new Check.RequestBuilder()
                 .setDescription("Remimburse $1")
                 .setAmount("1.00")
                 .setTo(
                         new Address.RequestBuilder()
                                 .setName("Harry Zhang")
                                 .setLine1("185  Berry Street")
                                 .setLine2("Ste 6100")
                                 .setCity("San Francisco")
                                 .setState("CA")

```

--------------------------------

### Create a Postcard in Ruby

Source: https://help.lob.com/developer-docs/use-case-guides/mass-deletion-setup

Use this snippet to create a new postcard. Ensure you have the Lob Ruby gem installed and your API key configured.

```ruby
require 'lob.rb'
require 'pp'

lob = Lob::Client.new(api_key: "test_XXXXXX")

newPostcard = lob.postcards.create(
   to: {
     name: "HARRY ZHANG",
     address_line1: "210 KING STREET",
     address_city: "SAN FRANCISCO",
     address_state: "CA",
     address_zip: "94107"
   },
   from: {
     name: "LEORE AVIDAR",
     address_line1: "185 BERRY ST",
     address_line2:  "SUITE 6100",
     address_city: "SAN FRANCISCO",
     address_state: "CA",
     address_zip: "94107"
   },
   front: "<html style='padding: 1in; font-size: 50;'>Front HTML</html>",
   back: "<html style='padding: 1in; font-size: 20;'>Back HTML</html>"
 )
//Save to your database with the postcard.id and a unique group id  
```

--------------------------------

### Create Postcard in C#/.NET

Source: https://help.lob.com/developer-docs/api-quickstart-guide

This C# code snippet shows how to create a postcard using the Lob API. Remember to replace '<YOUR_TEST_KEY>' with your Lob Test API Key and ensure you have the lob.dotnet SDK installed.

```csharp
using System;
using System.Collections.Generic;
using System.Diagnostics;
using lob.dotnet.Api;
using lob.dotnet.Client;
using lob.dotnet.Model;

namespace test_dotnet
{
   class Program
   {
       static void Main(string[] args)
       {
           Configuration config = new Configuration();
           config.BasePath = "https://api.lob.com/v1";
           // Configure HTTP basic authorization: basicAuth
           config.Username = "<YOUR_TEST_KEY>";

           Dictionary<string, string> mergeVariables = new Dictionary<string, string>();
           mergeVariables.Add("name", "Harry");

           PostcardsApi apiInstance = new PostcardsApi(config);

           AddressEditable to = new AddressEditable(
               "210 King St",  // addressLine1
               null,  // addressLine2
               "San Francisco",  // addressCity
               "CA",  // addressState
               "94107",  // addressZip
               CountryExtended.US,  // addressCounty

```

--------------------------------

### Create Postcard in Python

Source: https://help.lob.com/developer-docs/api-quickstart-guide

This Python code creates a postcard using HTML for the front and back, with merge variables for personalization. Replace '<YOUR_TEST_KEY>' with your Lob Test API Key. Ensure the 'lob-python' library is installed.

```python
import lob_python
from lob_python.exceptions import ApiException

from lob_python.model.postcard_editable import PostcardEditable
from lob_python.model.address_editable import AddressEditable
from lob_python.model.merge_variables import MergeVariables
from lob_python.model.country_extended import CountryExtended

from lob_python.api.postcards_api import PostcardsApi

configuration = lob_python.Configuration(
  username = "<YOUR_TEST_KEY>"
)

postcard_editable = PostcardEditable(
  description = "First Postcard",
  front = "<html style='padding: 1in; font-size: 50;'>Front HTML for {{name}}</html>",
  back = "<html style='padding: 1in; font-size: 20;'>Back HTML for {{name}}</html>",
  to = AddressEditable(
    name = "Harry Zhang",
    address_line1 = "210 King Street",
address_city = "San Francisco",
address_state = "CA",
address_zip = "94107",
  ),
  _from = AddressEditable(
    name = "Leore Avidar",
    address_line1 = "210 King Street",
    address_city = "San Francisco",
    address_state = "CA",
    address_zip = "94107",
    address_country = CountryExtended("US")
  ),
  merge_variables = MergeVariables(
    name = "Harry",
  ),
)

with lob_python.ApiClient(configuration) as api_client:
  api = PostcardsApi(api_client)

try:
  created_postcard = api.create(postcard_editable)
  print(created_postcard)
except ApiException as e:
  print(e)
```

--------------------------------

### Create Postcard with Custom Send Date in Python

Source: https://help.lob.com/developer-docs/use-case-guides/override-cancellation-window

This Python code demonstrates creating a postcard with a specified send date. Ensure the Lob Python library is installed and your API key is set.

```python
import lob
 
 lob.api_key = "<YOUR_TEST_KEY>"
 
 postcard = lob.Postcard.create(
 description = "First Postcard",
  to_address = {
    "name": "Harry Zhang",
    "address_line1": "210 King Street",
    "address_city": "San Francisco",
    "address_state": "CA",
    "address_zip": "94107"
  },
  from_address = {
    "name": "Leore Avidar",
    "address_line1": "210 King Street",
    "address_city": "San Francisco",
    "address_state": "CA",
    "address_zip": "94107",
    "address_country": "US"
  },
  front = "<html style='padding: 1in; font-size: 50;'>Front HTML for {{name}}</html>",
  back = "<html style='padding: 1in; font-size: 20;'>Back HTML for {{name}}</html>",
  merge_variables = {
    "name": "Harry"
  },
  send_date = "2022-07-01T14:00:00"  
 )
 
 print(postcard)
```

--------------------------------

### Create Postcard with Custom Send Date in Ruby

Source: https://help.lob.com/developer-docs/use-case-guides/override-cancellation-window

Use this Ruby script to schedule a postcard for a future send date. Make sure the 'lob.rb' gem is installed and your API key is configured.

```ruby
require 'lob.rb'
require 'pp'
 
lob = Lob::Client.new(api_key: "<TEST_API_KEY>")

pp lob.postcards.create(
  description: "First Postcard",
  to: {
    name: "Harry Zhang",
    address_line1: "210 King Street",
    address_city: "San Francisco",
    address_state: "CA",
    address_zip: "94107"
  },
  from: {
    name: "Leore Avidar",
    address_line1: "210 King Street",
    address_city: "San Francisco",
    address_state: "CA",
    address_zip: "94107"
  },
  merge_variables: { name: "Harry" },
  front: "<html style='padding: 1in; font-size: 50;'>Front HTML for {{name}}</html>",
  back: "<html style='padding: 1in; font-size: 20;'>Back HTML for {{name}}</html>",
  send_date: "2022-07-01T14:00:00"
)
```

--------------------------------

### Create Postcard with Custom Send Date in TypeScript

Source: https://help.lob.com/developer-docs/use-case-guides/override-cancellation-window

Use this snippet to create a postcard and specify a future send date for production. Ensure the Lob TypeScript SDK is installed and configured with your API key.

```typescript
import {Configuration, Postcard, PostcardsApi, PostcardEditable, CountryExtended } from "@lob/lob-typescript-sdk"
 
 async function demo() {
    const config: Configuration = new Configuration({
        username: "<YOUR_TEST_KEY>"
    })
 
    const postcardData : PostcardEditable = {
        to: {
          name: "Harry Zhang",
          address_line1: "210 King Street",
          address_city: "San Francisco",
          address_state: "CA",
          address_zip: "94107"
        },
        from: {
          name: "Leore Avidar",
          address_line1: "210 King Street",
          address_city: "San Francisco",
          address_state: "CA",
          address_zip: "94107",
          address_country: CountryExtended.Us
        },
        front:   "https://s3-us-west-2.amazonaws.com/public.lob.com/assets/templates/4x6_pc_template.pdf",
        back:   "https://s3-us-west-2.amazonaws.com/public.lob.com/assets/templates/4x6_pc_template.pdf",
        send_date:   "2022-07-01T14:00:00"
    }
 
    try {
        const result : Postcard = await new PostcardsApi(config).create(postcardData)
        return result
    } catch (err: any) {
        console.error(err)
    }
 }
 
 demo().then((result)=> console.log(result)).catch()
```

--------------------------------

### Create and Cancel Check if Recipient Moved (Ruby)

Source: https://help.lob.com/developer-docs/use-case-guides/ncoa-responses

This Ruby example shows how to create a check and cancel it if the recipient's address has changed, indicated by the 'recipient_moved' key in the response. Make sure the 'lob.rb' gem is included.

```ruby
require 'lob.rb'
require 'pp'
 
@lob = Lob::Client.new(api_key: "test_XXXXXXXX")
 
newCheck = @lob.checks.create(
    description: 'Reimbursement $1',
       to: {
         name: 'Harry Zhang',
         address_line1: '185 Berry St',
         address_line2: '# 6100',
         address_city: 'San Francisco',
         address_state: 'CA',
         address_zip: '94107'
       },
       from: {
         name: 'Leore Avidar',
         address_line1: '210 King St',
         address_city: 'San Francisco',
         address_state: 'CA',
         address_zip: '94107'
       },
       bank_account: 'bank_XXXXXXXX',
       amount: 1.00
 )
 
if(newCheck['to']['recipient_moved'])
   @lob.checks.destroy(newCheck.id)
   pp 'Recipient has moved - cancel'
end

```

--------------------------------

### Initialize TypeScript Project

Source: https://help.lob.com/developer-docs/use-case-guides/ingesting-tracking-events-with-webhooks

Set up a new directory and initialize a Node.js project with TypeScript support.

```bash
mkdir webhook-ts-example && cd webhook-ts-example
npm init -y
npx tsc --init
```

--------------------------------

### Create C#/.NET Console Project

Source: https://help.lob.com/developer-docs/api-quickstart-guide

Initialize a new C# console application project using the .NET CLI.

```bash
dotnet new console
```

--------------------------------

### Create and Activate Python Virtual Environment

Source: https://help.lob.com/developer-docs/api-quickstart-guide

Set up a Python virtual environment for your project. This isolates project dependencies.

```bash
python3 -m venv venv
```

```bash
source venv/bin/activate
```

--------------------------------

### Create Project Directories

Source: https://help.lob.com/developer-docs/use-case-guides/ingesting-tracking-events-with-webhooks

Create directories for TypeScript source files and compiled JavaScript output.

```bash
mkdir src
mkdir dist
```

--------------------------------

### Initialize Lob Python SDK

Source: https://help.lob.com/developer-docs/sdks-and-libraries

Import the lob library and set your API key to initialize the Lob Python SDK.

```python
import lob

lob.api_key = 'your-api-key'
```

--------------------------------

### Add Lob Ruby Gem to Gemfile

Source: https://help.lob.com/developer-docs/sdks-and-libraries

Add the Lob Ruby gem to your application's Gemfile for installation via Bundler.

```ruby
gem 'lob'
```

--------------------------------

### Expose Local Server with ngrok

Source: https://help.lob.com/developer-docs/use-case-guides/ingesting-tracking-events-with-webhooks

Use ngrok to create a public URL for your local webhook endpoint.

```bash
./ngrok http 3000
```

--------------------------------

### Create Java Maven Project

Source: https://help.lob.com/developer-docs/api-quickstart-guide

Generate a new Maven project for your Java application. This sets up the basic project structure.

```bash
mvn archetype:generate -DgroupId=com.company.app -DartifactId=my-app -DarchetypeArtifactId=maven-archetype-quickstart -DarchetypeVersion=1.4 -DinteractiveMode=false
```

--------------------------------

### Create Postcard with Metadata (Java)

Source: https://help.lob.com/developer-docs/use-case-guides/mass-deletion-setup

This Java snippet shows how to create a postcard with metadata, including a 'batch_id'. Initialize the Lob SDK and use the RequestBuilder for address and postcard creation.

```java
import java.util.Map;
import com.lob.Lob;
import com.lob.model.Address;
import com.lob.model.Postcard;
import com.lob.net.LobResponse;

public class App 
{
  public static void main( String[] args )
  {
     Lob.init("test_XXXXXXXX");

     Map<String, String> metaData = Map.of(
       "batch_id", "NEWYORK2022"
     );

     try {
        LobResponse<Postcard> response = new Postcard.RequestBuilder()
         .setTo(
             new Address.RequestBuilder()
                 .setName("HARRY ZHANG")
                 .setLine1("210 KING STREET")
                 .setCity("SAN FRANCISCO")
                 .setState("CA")
                 .setZip("94107")
             )
         .setFrom(
             new Address.RequestBuilder()
                 .setName("LEORE AVIDAR")
                 .setLine1("210 KING STREET")
                 .setCity("SAN FRANCISCO")
```

--------------------------------

### cURL Request to Lob API Addresses

Source: https://help.lob.com/developer-docs/postman-and-similar-tools

This snippet shows how to use cURL to make a GET request to the Lob API's addresses endpoint. Ensure your API key is included for authentication.

```bash
curl https://api.lob.com/v1/addresses \
-u test_0dc8d51e0acffcb1880e0f19c79b2f5b0cc:
```

--------------------------------

### Update package.json

Source: https://help.lob.com/developer-docs/use-case-guides/ingesting-tracking-events-with-webhooks

Configure package.json to specify the main entry point for the compiled JavaScript.

```json
{
  "name": "webhook-ts-example",
  "version": "1.0.0",
  "description": "",
  "main": "./dist/index.js",
  "scripts": {
    "build": "tsc",
    "start": "node dist/index.js"
  },
  "keywords": [],
  "author": "",
  "license": "ISC",
  "devDependencies": {
    "@lob/webhook": "^1.0.0",
    "@types/koa": "^2.13.5",
    "@types/node": "^18.0.0",
    "typescript": "^4.7.4"
  },
  "dependencies": {
    "koa": "^2.13.4"
  }
}
```

--------------------------------

### Create and Cancel Check if Recipient Moved (Python)

Source: https://help.lob.com/developer-docs/use-case-guides/ncoa-responses

This Python snippet demonstrates creating a check and subsequently canceling it if the recipient has moved, identified by the 'recipient_moved' attribute. Ensure the Lob Python library is installed.

```python
import lob
lob.api_key = "test_XXXXXXXX"
 
newCheck = lob.Check.create(
    description = 'Reimbursement $1',
       to_address = {
         'name': 'Harry Zhang',
         'address_line1': '185 Berry St',
         'address_line2': '# 6100',
         'address_city': 'San Francisco',
         'address_state': 'CA',
         'address_zip': '94107'
       },
       from_address = {
         'name': 'Leore Avidar',
         'address_line1': '210 King St',
         'address_city': 'San Francisco',
         'address_state': 'CA',
         'address_zip': '94107'
       },
       bank_account = 'bank_XXXXXXXX',
       amount = 1.00,
 )
 
if('recipient_moved' in newCheck.to_address.__dict__):
    lob.Check.delete(newCheck.id)
    print("Recipient has moved - cancel")

```

--------------------------------

### Create and Cancel Check if Recipient Moved (TypeScript)

Source: https://help.lob.com/developer-docs/use-case-guides/ncoa-responses

Use this snippet to create a check and then cancel it if the recipient's address has changed, as indicated by the 'recipient_moved' flag. Ensure you have the Lob TypeScript SDK installed.

```typescript
import {
    Configuration,
    ChecksApi,
    CheckEditable,
    CountryExtended,
    AddressEditable 
} from "@lob/lob-typescript-sdk"; 
  
async function demo() { 
    const config: Configuration = new Configuration({
        username: "test_XXXXXXXX", 
    }); 
  
    const checkToCreate = new CheckEditable({
        description: "Reimbursement $1",
        to: new AddressEditable({
            name: "HARRY ZHANG",
            address_line1: "185 BERRY ST",
            address_line2: "SUITE 6100",
            address_city: "SAN FRANCISCO",
            address_state: "CA",
            address_zip: "94107"
        }),
        from: new AddressEditable({
            name: "LEORE AVIDAR",
            address_line1: "210 King Street",
            address_city: "SAN FRANCISCO",
            address_state: "CA",
            address_zip: "94107",
            address_country: CountryExtended.Us, 
        }),
        bank_account: "bank_XXXXXXXX",
        amount: 1, 
    }); 
  
    const checksApi = new ChecksApi(config); 
    try { 
        const newCheck = await checksApi.create(checkToCreate);
        if (newCheck.to?.recipient_moved) { 
            console.log("Recipient has moved - cancel ") 
            await checksApi.cancel(newCheck.id);
        }
    } catch (err) {
        console.error(err);
    }
}
  
demo().then().catch(); 

```

--------------------------------

### Create Postcard with HTML Content (Python)

Source: https://help.lob.com/developer-docs/use-case-guides/mass-deletion-setup

This Python snippet demonstrates creating a postcard with specified front and back HTML content. It requires your Lob API key to be set.

```python
import lob
lob.api_key = "test_XXXXXXXXX"
 
postcard = lob.Postcard.create(
   to_address = {
     "name": "HARRY ZHANG",
     "address_line1": "210 KING STREET",
     "address_city": "SAN FRANCISCO",
     "address_state": "CA",
     "address_zip": "94107"
   },
   from_address = {
     "name": "LEORE AVIDAR",
     "address_line1":  "185 BERRY ST",
     "address_line2": "SUITE 6100",
     "address_city": "SAN FRANCISCO",
     "address_state": "CA",
     "address_zip": "94107",
     "address_country": "US"
     },
   front = "<html style='padding: 1in; font-size: 50;'>Front HTML for Postcard</html>",
   back = "<html style='padding: 1in; font-size: 20;'>Back HTML for Postcard</html>"
)
  
```

--------------------------------

### Create Postcard with Metadata (Ruby)

Source: https://help.lob.com/developer-docs/use-case-guides/mass-deletion-setup

This Ruby snippet shows how to create a postcard with metadata, using a 'batch_id' for batch identification. Initialize the Lob client with your API key.

```ruby
require 'lob.rb'
require 'pp'

lob = Lob::Client.new(api_key: "test_XXXXXX")

newPostcard = lob.postcards.create(
   to: {
     name: "HARRY ZHANG",
     address_line1: "210 KING STREET",
     address_city: "SAN FRANCISCO",
     address_state: "CA",
     address_zip: "94107"
   },
   from: {
     name: "LEORE AVIDAR",
     address_line1: "185 BERRY STREET",
     address_line2:  "SUITE 6100",
     address_city: "SAN FRANCISCO",
     address_state: "CA",
     address_zip: "94107"
   },
   front: "<html style='padding: 1in; font-size: 50;'>Front HTML</html>",
   back: "<html style='padding: 1in; font-size: 20;'>Back HTML</html>",
   metadata: {
     "batch_id": "NEWYORK2022"
   }
 )
```

--------------------------------

### Create Postcard via API

Source: https://help.lob.com/developer-docs/api-quickstart-guide

This C# code snippet demonstrates how to create a postcard object with recipient and sender addresses, HTML content for the front and back, and then send it using the API. It includes basic error handling for API exceptions.

```csharp
using System;
using System.Collections.Generic;
using System.Globalization;
using System.IO;
using System.Text;
using Org.OpenAPITools.Client;
using Org.OpenAPITools.Model;

namespace Org.OpenAPITools.Api {

    public class PostcardsApiExample {

       public static void Main(string[] args) {

           Configuration.Default.AccessToken = "YOUR_API_KEY";

           var apiInstance = new PostcardsApi();
           var mergeVariables = new Dictionary<String, String>();
           mergeVariables.Add("name", "Harry Zhang");

           AddressEditable to = new AddressEditable(
               "210 King St",  // addressLine1
               null,  // addressLine2
               "San Francisco",  // addressCity
               "CA",  // addressState
               "94107",  // addressZip
               CountryExtended.US,  // addressCounty
               null,  // description
               
```

```csharp
AddressEditable from = new AddressEditable(
    "210 King St",  // addressLine1
    null,  // addressLine2
    "San Francisco",  // addressCity
    "CA",  // addressState
    "94107",  // addressZip
    CountryExtended.US,  // addressCounty
    null,  // description
    
```

```csharp
PostcardEditable postcardEditable = new PostcardEditable(
    to.ToJson(),  // to
    from.ToJson(),  // from
    default(PostcardSize),  // size
    
```

```csharp
try
           {
               // create
               Postcard result = apiInstance.create(postcardEditable);
               Console.WriteLine(result.ToString());
           }
           catch (ApiException e)
           {
               Console.WriteLine("Exception when calling PostcardsApi.create: " + e.Message );
               Console.WriteLine("Status Code: "+ e.ErrorCode);
               Console.WriteLine(e.StackTrace);
           }
       }
   }
}
```

--------------------------------

### Configure TypeScript Compiler

Source: https://help.lob.com/developer-docs/use-case-guides/ingesting-tracking-events-with-webhooks

Create a tsconfig.json file to configure the TypeScript compiler settings.

```json
{
  "compilerOptions": {
    "target": "es6",
    "module": "commonjs",
    "outDir": "./dist",
    "rootDir": "./src",
    "strict": true,
    "esModuleInterop": true
  },
  "include": [
    "src/**/*.ts"
  ],
  "exclude": [
    "node_modules"
  ]
}
```

--------------------------------

### Run TypeScript Code

Source: https://help.lob.com/developer-docs/use-case-guides/ingesting-tracking-events-with-webhooks

Compile the TypeScript code to JavaScript and run the server.

```bash
npm run build
npm start
```

--------------------------------

### Create Webhook Endpoint

Source: https://help.lob.com/developer-docs/use-case-guides/ingesting-tracking-events-with-webhooks

Implement the webhook endpoint using KOA to handle incoming tracking events.

```typescript
import Koa from 'koa';
import bodyParser from 'koa-bodyparser';
import { verifyLob } from '@lob/webhook';

const app = new Koa();

app.use(bodyParser());

app.use(async (ctx, next) => {
  // Verify the signature
  const signature = ctx.request.headers['x-lob-signature'];
  const payload = ctx.request.body;

  if (!signature || !verifyLob(process.env.WEBHOOK_SECRET, payload, signature)) {
    ctx.status = 401;
    ctx.body = 'Invalid signature';
    return;
  }

  // Process the event
  console.log('Received Lob event:', payload.event.type);
  console.log(payload);

  ctx.status = 200;
  await next();
});

const PORT = process.env.PORT || 3000;
app.listen(PORT, () => {
  console.log(`Server listening on port ${PORT}`);
});
```

--------------------------------

### Create Postcard

Source: https://help.lob.com/developer-docs/api-quickstart-guide

This snippet demonstrates how to create a postcard using the Lob API. It includes details for the 'to' and 'from' addresses, and the HTML content for the front and back of the postcard.

```APIDOC
## Create Postcard

### Description
This endpoint creates a new postcard object. You can specify recipient and sender details, as well as the HTML content for the front and back of the postcard.

### Method
POST

### Endpoint
/postcards

### Parameters
#### Request Body
- **description** (string) - Optional - An optional description for the postcard.
- **to[name]** (string) - Required - The name of the recipient.
- **to[address_line1]** (string) - Required - The first line of the recipient's street address.
- **to[address_city]** (string) - Required - The recipient's city.
- **to[address_state]** (string) - Required - The recipient's state.
- **to[address_zip]** (string) - Required - The recipient's ZIP code.
- **from[name]** (string) - Required - The name of the sender.
- **from[address_line1]** (string) - Required - The first line of the sender's street address.
- **from[address_city]** (string) - Required - The sender's city.
- **from[address_state]** (string) - Required - The sender's state.
- **from[address_zip]** (string) - Required - The sender's ZIP code.
- **front** (string) - Required - HTML content for the front of the postcard.
- **back** (string) - Optional - HTML content for the back of the postcard.
- **merge_variables[name]** (string) - Optional - A merge variable to be used in the HTML content.
```

--------------------------------

### Create Postcard in Java

Source: https://help.lob.com/developer-docs/api-quickstart-guide

This Java code demonstrates how to create a postcard using the Lob API. Replace '<YOUR_LOB_API_KEY>' with your actual API key. Ensure you have the Lob Java SDK and Gson library added to your Maven project.

```java
package com.company.app;

import com.lob.api.ApiClient;
import com.lob.api.ApiException;
import com.lob.api.Configuration;
import com.lob.api.auth.*;
import com.lob.model.*;
import com.lob.api.client.PostcardsApi;

public class App
{
    public static void main( String[] args )
    {

        ApiClient lobClient = Configuration.getDefaultApiClient();

        // Configure HTTP basic authorization: basicAuth
        HttpBasicAuth basicAuth = (HttpBasicAuth) lobClient.getAuthentication("basicAuth");
        basicAuth.setUsername("<YOUR_LOB_API_KEY>");

        PostcardsApi apiInstance = new PostcardsApi(lobClient);
        PostcardEditable postcardEditable = new PostcardEditable();

        AddressEditable to = new AddressEditable();
        to.setName("MORTICIA ADDAMS");
        to.setAddressLine1("1313 CEMETERY LN");
        to.setAddressCity("WESTFIELD");
        to.setAddressState("NJ");
        to.setAddressZip("07091");

        AddressEditable to = new AddressEditable();
        to.setName("MORTICIA ADDAMS");
        to.setAddressLine1("1313 CEMETERY LN");
        to.setAddressCity("WESTFIELD");
        to.setAddressState("NJ");
        to.setAddressZip("07091");

        AddressEditable from = new AddressEditable();
        from.setName("FESTER");
        from.setAddressLine1("001 CEMETERY LN");
        from.setAddressLine2("SUITE 666");
        from.setAddressCity("WESTFIELD");
        from.setAddressState("NJ");
        from.setAddressZip("07091");

        Gson gson = new Gson();
        postcardEditable.setTo(gson.toJson(to));
        postcardEditable.setFrom(gson.toJson(from));
        postcardEditable.setFront("https://s3-us-west-2.amazonaws.com/public.lob.com/assets/templates/4x6_pc_template.pdf");
        postcardEditable.setBack("https://s3-us-west-2.amazonaws.com/public.lob.com/assets/templates/4x6_pc_template.pdf");

        try {
            Postcard result = apiInstance.create(postcardEditable);
            System.out.println(result);
        } catch (ApiException e) {
            System.err.println("Exception when calling PostcardsApi#postcardCreate");
            System.err.println("Status code: " + e.getCode());
            System.err.println("Reason: " + e.getResponseBody());
            System.err.println("Response headers: " + e.getResponseHeaders());
            e.printStackTrace();
        }
    }
}

```

--------------------------------

### Create Postcard with Metadata (TypeScript)

Source: https://help.lob.com/developer-docs/use-case-guides/mass-deletion-setup

Use this snippet to create a single postcard and include metadata with a unique batch identifier. Ensure you have the Lob SDK configured.

```typescript
const config: Configuration = new Configuration({
username: "test_XXXXXXXXX",
});

const postCardExample: PostcardEditable = {
    to: {
      company: "HARRY ZHANG",
      address_line1: "210 KING STREET",
      address_city: "SAN FRANCISCO",
      address_state: "CA",
      address_zip: "94107",
      address_country: CountryExtended.Us,
    },
    from: {
      company: "LEORE AVIDAR",
      address_line1: "185 BERRY ST",
      address_line2: "SUITE 6100",
      address_city: "SAN FRANCISCO",
      address_state: "CA",
      address_zip: "94107",
      address_country: CountryExtended.Us,
    },
    front = "<html style='padding: 1in; font-size: 50;'>Front HTML</html>",
    back = "<html style='padding: 1in; font-size: 20;'>Back HTML</html>",
    metadata: {
      batch_id: "NEWYORK2022"
   }
 };
const postcardsApi = new PostcardsApi(config);
const postcard = await postcardsApi.create(postCardExample);
```

--------------------------------

### Create Postcard in Ruby

Source: https://help.lob.com/developer-docs/api-quickstart-guide

This Ruby script creates a postcard with specified recipient and sender details, merge variables, and HTML content for front and back. Replace '<TEST_API_KEY>' with your Lob Test API Key.

```ruby
require 'lob.rb'
require 'pp'
 
lob = Lob::Client.new(api_key: "<TEST_API_KEY>")
 
pp lob.postcards.create(
 description: "First Postcard",
  to: {
    name: "Harry Zhang",
    address_line1: "210 King Street",
    address_city: "San Francisco",
    address_state: "CA",
    address_zip: "94107"
  },
  from: {
    name: "Leore Avidar",
    address_line1: "210 King Street",
    address_city: "San Francisco",
    address_state: "CA",
    address_zip: "94107"
  },
  merge_variables: { name: "Harry" },
  front: "<html style='padding: 1in; font-size: 50;'>Front HTML for {{name}}</html>",
  back: "<html style='padding: 1in; font-size: 20;'>Back HTML for {{name}}</html>"
)
```

--------------------------------

### Track Address Changes in Python

Source: https://help.lob.com/developer-docs/use-case-guides/visibility-of-address-changes

Compares the input 'to' address with the response 'to' address when creating a postcard to identify any changes made by Lob's services.

```Python
from lob import Lob

lob = Lob('YOUR_LOB_API_KEY')

def track_address_changes():
    try:
        postcard = lob.postcards.create(
            description='Customer Service Postcard',
            to_address={
                'name': 'Lob.com',
                'address_line1': '123 Main St',
                'address_city': 'San Francisco',
                'address_state': 'CA',
                'address_zip': '94107',
                'address_country': 'US'
            },
            from_address={
                'name': 'Lob.com',
                'address_line1': '123 Main St',
                'address_city': 'San Francisco',
                'address_state': 'CA',
                'address_zip': '94107',
                'address_country': 'US'
            },
            message='Hello, World!',
            metadata={'campaign_id': 'test-campaign'}
        )

        original_address = postcard.to
        corrected_address = postcard.to

        # Compare original_address and corrected_address to find differences
        print(f'Original Address: {original_address}')
        print(f'Corrected Address: {corrected_address}')

        # Example: Simple comparison for demonstration
        if original_address != corrected_address:
            print('Address was changed by Lob.')
            # Implement custom logic here to log or display the changes
        else:
            print('Address remained the same.')

    except Exception as e:
        print(f'Error creating postcard: {e}')

track_address_changes()

```

--------------------------------

### Track Address Changes in PHP

Source: https://help.lob.com/developer-docs/use-case-guides/visibility-of-address-changes

Compares the input 'to' address with the response 'to' address when creating a postcard to identify any changes made by Lob's services.

```PHP
<?php

require_once 'vendor/autoload.php';

use 
Lob\Lob;

$lob = new Lob('YOUR_LOB_API_KEY');

try {
    $postcard = $lob->postcards()->create([
        'description' => 'Customer Service Postcard',
        'to' => [
            'name' => 'Lob.com',
            'address_line1' => '123 Main St',
            'address_city' => 'San Francisco',
            'address_state' => 'CA',
            'address_zip' => '94107',
            'address_country' => 'US'
        ],
        'from' => [
            'name' => 'Lob.com',
            'address_line1' => '123 Main St',
            'address_city' => 'San Francisco',
            'address_state' => 'CA',
            'address_zip' => '94107',
            'address_country' => 'US'
        ],
        'message' => 'Hello, World!',
        'metadata' => ['campaign_id' => 'test-campaign']
    ]);

    $originalAddress = $postcard->to;
    $correctedAddress = $postcard->to;

    // Compare originalAddress and correctedAddress to find differences
    echo 'Original Address: ' . print_r($originalAddress, true) . "\n";
    echo 'Corrected Address: ' . print_r($correctedAddress, true) . "\n";

    // Example: Simple comparison for demonstration
    if (json_encode($originalAddress) !== json_encode($correctedAddress)) {
        echo 'Address was changed by Lob.\n';
        // Implement custom logic here to log or display the changes
    } else {
        echo 'Address remained the same.\n';
    }

} catch (
Lob\Exception\LobException $e) {
    echo 'Error creating postcard: ' . $e->getMessage() . "\n";
}

?>

```