Kaizen #84 - PHP SDK [Part I]

Kaizen #84 - PHP SDK [Part I]

Hello and welcome to another Kaizen week!

In this week's post, we'll show you how to get started with Zoho CRM's PHP SDK, and walk you through the configuration and initialization process.

PHP Software Development Kit

PHP SDK allows you to create client PHP applications that can be integrated with Zoho CRM effortlessly. It serves as a wrapper for the REST APIs, thus making it easier to use the services of Zoho CRM.

Why PHP SDK?

Easy authentication: You don't have to worry about manually managing authentication because the PHP SDK takes care of generating access/refresh tokens for you.
Easy and Efficient data exchange: With the PHP SDK, you can easily exchange data between Zoho CRM and your client PHP application, where the CRM entities are modelled as classes. You can declare and define CRM API equivalents as simple functions in your PHP application.

Prerequisites 

  • The client app must have PHP 7 or above with a cURL extension. cURL extension is used to connect and communicate with the Zoho CRM APIs.
  • The client app must have the PHP SDK installed through Composer. 

How to start using the PHP SDK?

  1. Prerequisite : Register your application with Zoho CRM.
  2. Install the PHP SDK.
  3. Knowledge Base : Token Persistence
  4. Configuration 
  5. initialization.

1. Register your application with Zoho CRM

Registering your application with Zoho CRM is a mandatory step in order to authenticate and authorize API calls using the OAuth2.0 standards.
  1. Go to https://api-console.zoho.com
  2. Click on Get Started or +ADD CLIENT.
  3. Choose the Client Type.
  4. Fill in the necessary details and click CREATE. Once you successfully register your self-client, you will receive a Client ID and Client Secret.

2. Install PHP SDK 

1. Install Composer, if not already installed. Please check the corresponding link for installation instructions.

2. Install PHP-SDK using Composer
  • Navigate to the workspace of your client app.
  • Run the following command in the workspace. Upon successful installation, the system will create a package named vendor in the workspace of your client app.   Note : This command installs SDK for API v2.1.

    composer require zohocrm/php-sdk-2.1

3. To use the SDK in your project, add the following line in your project PHP files. This loads and includes our PHP-SDK library in your project. If you skip this step, you will get a fatal error in response due to the missing libraries.

require 'vendor/autoload.php';

3. Token Persistence

Token persistence refers to storing and utilizing authentication tokens provided by Zoho, enabling the SDK to refresh the access tokens without the need for user intervention. The SDK offers three types of persistence - File, DB, and Custom - with file persistence being the default method. 
The persistence is achieved by writing an implementation of the inbuilt TokenStore interface, which has the following callback methods. 

Method
Description
getToken($user, $token)
Invoked before firing a request to fetch the saved tokens. This method returns an implementation of Token interface object for the library to process it.
saveToken($user, $token)
Invoked after fetching access and refresh tokens from Zoho. This method saves the token details.
deleteToken($token)
This method is used to delete the given token details.
getTokens()
This method is used to retrieve all the stored tokens.
deleteTokens() 
The method to delete all the stored tokens.
getTokenById($id, $token) 
This method is used to retrieve the user token details based on the unique ID.

a. Token Persistence using a Database

Database persistence is a technique that involves storing and retrieving data from a database. If you prefer using database persistence, you can use MySQL. 
Create a table in your database with the required columns. For example, if you want to persist your tokens in a table named token in database named zoho, use the following:
CREATE DATABASE zoho; // use this to create database named zoho
// use this to create a table named token, with the necessary columns
CREATE TABLE token ( 
  id varchar(255) NOT NULL,
  user_mail varchar(255) NOT NULL,
  client_id varchar(255),
  client_secret varchar(255),
  refresh_token varchar(255),
  access_token varchar(255),
  grant_token varchar(255),
  expiry_time varchar(20),
  redirect_url varchar(255),
  primary key (id)
);

In this example, your tokens will be persisted in the token table in your zoho database.

b. File Persistence

File Persistence allows storing and retrieving the authentication tokens from the given file path. The file contains id, user_mail, client_id, client_secret, refresh_token, access_token, grant_token, expiry_time and redirect_url. 

c. Custom Persistence

Custom Persistence refers to a technique where users can create their own method of storing and retrieving authentication tokens. To use this method, users need to implement the TokenStore interface and override its methods according to their own logic.

4. Configuration

Configuration is a critical step in which you set up SDK's configuration details like user authentication, token persistence, logging and API call timeout settings, and more. Listed below are the keys that you define in this step.

Key
Description
user
mandatory
Represents the mail id, which is used to identify and fetch tokens from the File or DB.
environment
mandatory
Represents the data centre details in Domain::Environment pattern.
Domains : USDataCenter, EUDataCenter, INDataCenter, CNDataCenter, AUDataCenter
Environments : PRODUCTION(), DEVELOPER(), SANDBOX()
token
mandatory
Contains user token details. Depending on the tokens, you can choose grantToken flow, refreshToken flow or accessToken flow.
logger
optional
Contains the configuration for logging exceptions and API call information. By default, the logs will be available in the workspace as sdk_logs.log.
store
optional
Contains details for the Token Persistence object. You can choose between DB Store, File Store or Custom Store, and configure accordingly.
SDKConfig
optional
Contains additional configuration details like timeout, autorefresh fields, picklistvalidation, etc
requestProxy
optional
Contains the details of the proxy, if you are using a proxy server to authenticate and make the API calls.
resourcePath
optional
The path containing the absolute directory path to store user specific files containing the module fields information.


Let us discuss how to configure each of them, in detail.
a. user : The user key will be used to store and identify the tokenstore details in the DB or File Storage for token persistence. Create an instance of UserSignature that identifies the current user with the following :
  1. $user = new UserSignature("patricia@zoho.com");
b. environment : The API environment which decides the domain and the URL to make API calls. 
  1. $environment = USDataCenter::PRODUCTION();
c. token : Create an instance of OAuthToken with the information that you get after registering your Zoho client. Depending on the tokens available with you, you can choose one of the following flows. 
Note : You need to generate the tokens (grant/access/refresh) beforehand. 
  • grantToken flow - You should use the grant Token for configuration.
    $token = (new OAuthBuilder())
      ->clientId("clientId")
      ->clientSecret("clientSecret")
      ->grantToken("grantToken")
      ->redirectURL("redirectURL")
      ->build();

  • refreshToken flow -In this flow, use the refresh token.
    $token = (new OAuthBuilder())
      ->clientId("clientId")
      ->clientSecret("clientSecret")
      ->refreshToken("refreshToken")
      ->redirectURL("redirectURL")
      ->build();

  • accessToken flow - You can use the access token to configure in this flow. Please note that the token will not be persisted in this case, and the access token will be directly used to make the API calls.

    $token = (new OAuthBuilder()
      ->accessToken("accessToken")
      ->build(); 

d. logger : Create an instance of Logger Class to log exception and API information. You can set the level you want to log (FATAL, ERROR, WARNING, INFO, DEBUG, TRACE, ALL, OFF), and also configure the file path and file name for the log file.

$logger = (new LogBuilder())
->level(Levels::INFO)
->filePath("/Documents/php_sdk_log.log")
->build();

e. store : Configure your token persistence using this method. If this is skipped, the SDK creates the sdk_tokens.txt in the current working directory to persist the tokens by default.
  • DB Store - Configure the Database details, where you want to store your tokens.
    $tokenstore = (new DBBuilder())
    ->host("hostName")
    ->databaseName("dataBaseName")
    ->userName("userName")
    ->password("password")
    ->portNumber("portNumber")
    ->tableName("tableName")
    ->build();

  • File store - Give the absolute file path, where you want to store the tokens. 
    $tokenstore = new FileStore("absolute_file_path");

  • Custom Store - In this method, you can implement your own method for storing and retrieving the tokens. Please note that to do so, you must implement the TokenStore interface, and override its callback methods (getToken, saveToken, deleteToken, getTokens, deleteTokens, getTokenById). 
    $tokenstore = new CustomStore();

Note :  The corresponding storage will  have id, user_mail, client_id, client_secret, refresh_token, access_token, grant_token, expiry_time and redirect_url. The id is a unique system generated key.

f. SDKConfig : The additional SDK configurations are taken care of with this method. 

Configuration Key
Description
autoRefreshFields
Default Value : False
A boolean configuration key to enable or disable automatic refreshing of module fields in the background. If set to true, fields are refreshed every hour, and if set to false, fields must be manually refreshed or deleted.
pickListValidation
Default Value : True
This field enables or disables pick list validation. If enabled, user input for pick list fields is validated, and if the value does not exist in the pick list, the SDK throws an error. If disabled, the input is not validated and the API call is made.
enableSSLVerification
Default Value : True
A boolean field to enable or disable curl certificate verification. If set to true, the SDK verifies the authenticity of certificate. If set to false, the SDK skips the verification.
connectionTimeout
Default Value : 0
The maximum time (in seconds) to wait while trying to connect. Use 0 to wait indefinitely.
timeout
Default Value : 0
The maximum time (in seconds) to allow cURL functions to execute. Use 0 to wait indefinitely.
  1. $autoRefreshFields = false;
  2. $pickListValidation = false;
  3. $enableSSLVerification = true;
  4. $connectionTimeout = 2;
  5. $timeout = 2;
  6. $sdkConfig = (new SDKConfigBuilder())
  7. ->autoRefreshFields($autoRefreshFields)
  8. ->pickListValidation($pickListValidation)
  9. ->sslVerification($enableSSLVerification)
  10. ->connectionTimeout($connectionTimeout)
  11. ->timeout($timeout)
  12. ->build();
g. requestProxy : Create an instance of RequestProxy containing the proxy properties of the user. Configure this only if you're using a proxy server to make the API calls.

$requestProxy = (new ProxyBuilder())
 ->host("proxyHost")
 ->port("proxyPort")
 ->user("proxyUser")
 ->password("password")
 ->build();

h. resourcePath : Configure path containing the absolute directory path to store user specific files containing module fields information.

$resourcePath = "/Documents/phpsdk-application";

5. Initilization

Once you have completed the configuration process, you can move on to initializing the SDK and begin making API requests.

Here is a sample code to initialize the SDK, using refresh token flow and DB Persistence.

<?php
use com\zoho\api\authenticator\OAuthBuilder;
use com\zoho\api\authenticator\store\DBBuilder;
use com\zoho\api\authenticator\store\FileStore;
use com\zoho\crm\api\InitializeBuilder;
use com\zoho\crm\api\UserSignature;
use com\zoho\crm\api\dc\USDataCenter;
use com\zoho\api\logger\LogBuilder;
use com\zoho\api\logger\Levels;
use com\zoho\crm\api\SDKConfigBuilder;
use com\zoho\crm\api\ProxyBuilder;
use com\zoho\api\authenticator\store\DBBuilder;

require_once "vendor/autoload.php";

class Initialize
{
  public static function initialize()
  {
    $user = new UserSignature("patricia@zoho.com");
    $environment = USDataCenter::PRODUCTION();
    $token = (new OAuthBuilder())
    ->clientId("1000.xxxxxxxxxxxxxxxx")
    ->clientSecret("554a9776d10ff016a92c1eb01xxxxxxxxxx")
    ->refreshToken("1000.xxxxxxxxxxxxxxxxxxxx")
    ->redirectURL("www.zoho.com")
    ->build();
    $logger = (new LogBuilder())
    ->level(Levels::INFO)
    ->filePath("/Documents/php_sdk_log.log")
    ->build();
   $tokenstore = (new DBBuilder())
    ->host("insert_your_hostname_here")
    ->databaseName("insert_your_database_name_here")
    ->userName("insert_your_db_username_here")
    ->password("insert_your_db_password_here")
    ->portNumber("insert_your_portnumber_here")
    ->tableName("insert_your_table_name_here")
    ->build();
    $autoRefreshFields = false;
    $pickListValidation = false;
    $connectionTimeout = 2;
    $timeout = 2;
    $sdkConfig = (new SDKConfigBuilder())
    ->autoRefreshFields($autoRefreshFields)
    ->pickListValidation($pickListValidation)
    ->sslVerification($enableSSLVerification)
    ->connectionTimeout($connectionTimeout)
    ->timeout($timeout)
    ->build();
    $resourcePath = "/Documents/phpsdk-application";
    $requestProxy = (new ProxyBuilder())
    ->host("proxyHost")
    ->port("proxyPort")
    ->user("proxyUser")
    ->password("password")
    ->build();
    (new InitializeBuilder())
    ->user($user)
    ->environment($environment)
    ->token($token)
    ->store($tokenstore)
    ->SDKConfig($configInstance)
    ->resourcePath($resourcePath)
    ->logger($logger)
    ->requestProxy($requestProxy)
    ->initialize();
  }
}
?>


You are now all set to explore the functionalities of SDK. Here is a sample code to get the records from Leads module, with the ifmodifiedsince header.

<?php
use com\zoho\api\authenticator\OAuthBuilder;
use com\zoho\crm\api\dc\USDataCenter;
use com\zoho\crm\api\InitializeBuilder;
use com\zoho\crm\api\UserSignature;
use com\zoho\crm\api\record\RecordOperations;
use com\zoho\crm\api\record\GetRecordsHeader;
use com\zoho\crm\api\HeaderMap;
use com\zoho\crm\api\ParameterMap;
require_once "vendor/autoload.php";

class Record
{
    public static function initialize()
    {
        $user = new UserSignature('myname@mydomain.com');
        $environment = USDataCenter::PRODUCTION();
        $token = (new OAuthBuilder())
        ->clientId("1000.xxxxxxx")
        ->clientSecret("4b5baxxxxxxxxxxxxf")
        ->grantToken("1000.xxxxx")
        ->build();
        (new InitializeBuilder())
            ->user($user)
            ->environment($environment)
            ->token($token)
            ->initialize();
    }

    public static function getRecords()
    {
        $recordOperations = new RecordOperations();
        $paramInstance = new ParameterMap();
        $headerInstance = new HeaderMap();
     $ifmodifiedsince = date_create("2022-06-01T12:00:00+05:30")->setTimezone(new \DateTimeZone(date_default_timezone_get()));
        $headerInstance->add(GetRecordsHeader::IfModifiedSince(), $ifmodifiedsince);
        $response = $recordOperations->getRecords("Leads", $paramInstance, $headerInstance);
        echo($response->getStatusCode() . "\n");
        print_r($response);
    }
}
Record::initialize();
Record::getRecords();


Next week, we will dive deeper and provide more sample codes to help you further. Stay tuned!

If you have any queries, let us know the comments below, or drop an email to support@zohocrm.com. We would love to hear from you. 



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