Kaizen #18 - Ruby SDK

Kaizen #18 - Ruby SDK

Hello everyone!
Welcome back to another week of Kaizen!
This week, we will discuss the Ruby SDK.

What is the Ruby SDK for Zoho CRM?

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

Here is a sample of how the SDK acts as a middle ware between Zoho CRM and a client Ruby Application.


What can you do with the Ruby SDK?
  • Exchange data between Zoho CRM and the client application where the CRM entities are modeled as classes.
  • Authenticate your application easily every time you sync data between Zoho CRM and your application, as the SDK takes care of generating the access/refresh tokens automatically.
Environment Setup
The client app must have the Ruby version 2.3.7 or above installed. Refer to Ruby Installation for the steps to install Ruby.

How to Start using the Ruby SDK?
Follow the below steps:
  • Step-1: Register your application (Self Client or Web-based client)
  • Step-2: Install the SDK
  • Step-3: Initialize the SDK
    3.a. Choose the token persistence method
    3.b. Set up the configuration dictionary
    3.c. Generate the tokens
  • Step-4: Connect to Zoho CRM through the available methods
Let us now discuss these steps in detail.

Step-1: Register your application

All the Zoho CRM APIs are authenticated by the OAuth2.0 standards. It is mandatory to authenticate your application with Zoho.
You can register your application either as a Self Client (single user app) or a web-based app (multiple users app).
1.a. Self Client
  1. Go to https://api-console.zoho.com.
  2. Click ADD CLIENT.
  3. Choose the Client Type as Self Client, and click CREATE.
  4. You will receive a client ID and a client secret upon successful registration.
1.b. Web-based Client
  1. Go to https://api-console.zoho.com.
  2. Click ADD CLIENT.
  3. Choose the client as Web based and click CREATE NOW.
  4. Specify the client name, homepage URL of your application's UI, and a redirect URI to which you want to redirect the users after they grant consent to your application.
  5. Click CREATE.

  6. Your Client ID and Client Secret will be displayed.
Step-2: Install the SDK

The Ruby SDK is available as a gem. 
Run the below command to install the Ruby SDK for Zoho CRM.

gem install ZCRMSDK

Step-3: Initialize the SDK 

Initializing the SDK involves the following steps.

  • Step 3.a - Choosing the token persistence method
  • Step 3.b - Setting up the configuration dictionary
  • Step 3.c - Generating the tokens

3.a. Token Persistence
Your application should retain tokens (grant, access, and refresh tokens) to automate the process of data transfer between your Ruby application and Zoho CRM.

You can persist (store) the tokens in three ways.
a. MySQL Persistence (default)
b. File Persistence
c. Custom DB Persistence

a. MySQL Persistence
When you want to store the tokens in the MySQL DB, ensure that MySQL2 is installed.
Run the below command to install MySQL2.

gem install mysql2 -v 0.5.2

For this type of persistence, you must include the following keys in the configuration dictionary (discussed in the next section), along with other mandatory keys.

"mysql_username":"root",
"mysql_password":"*****",
"mysql_port":"port_number"

Note
When you use MySQL persistence, ensure that
  • MySQL runs in the same machine serving at the mentioned port. (by default 3306).
  • There is a database named zohooauth.
  • There is a table name oauthtokens with the columns useridentifier (varchar(100)), accesstoken (varchar(100)), refreshtoken (varchar(100)) and expirytime (bigint).

b. File Persistence
If you want to store the tokens in a file, you can create a file named zcrm_oauthtokens.txt and provide the absolute path of the folder containing this file in the below key of the configuration array.

"token_persistence_path":"path_to_the_folder_containing_the_txt_file"

If you do not create this file, the SDK itself creates this file in the path you have specified, and persists the token there.
Note: This method is recommended only for self client apps.

c. Custom DB Persistence
To use this method, you need to provide the following keys in the configuration dictionary.

"persistence_handler_class_path":"absolute path to the custom DB implementation"
"persistence_handler_class":"class name of the custom implementation".

You can use the inbuilt ZohoPersistenceHandler interface and include the following custom functions.

  • saveOAuthData(ZohoOAuthTokens tokens)
  • deleteOAuthTokens($userEmailId)
  • getOAuthTokens($userEmailId)
Note
The order of precedence for token persistence is custom, file, and DB persistence. That is, if you provide the details for custom persistence (in persistence_handler_class_path) and file persistence details (in token_persistence_path), then custom persistence is given priority over file.

3.b. Configuration dictionary
The below tables contains the list of keys you must include in the configuration dictionary based on the type of persistence.

Mandatory Keys

File Persistence
MySQL Persistence
Custom DB Persistence
client_id
client_id
client_id
client_secret
client_secret
client_secret
redirect_uri
redirect_uri
redirect_uri
token_persistence_path
db_username
persistence_handler_class
-
db_password
persistence_handler_class_path
-
db_port
-
current_user_email
current_user_email
current_user_email

Optional Keys

File Persistence
MySQL Persistence
Custom DB Persistence
application_log_file_path
application_log_file_path
application_log_file_path
log_in_console
log_in_console
log_in_console
sandbox
sandbox
sandbox
access_type
access_type
access_type
accounts_url
accounts_url
accounts_url
api_base_url
api_base_url
api_base_url
api_version
api_version
api_version

Where,
  • client_id, client_secret, and redirect_uri - Client details you received after registering your application. For self client apps, you can pass a dummy value for the redirect uri.
  • token_persistence_path - The relative path to store the OAuth tokens in the zcrm_oauthtokens.txt file. This key is mandatory if you want to use file persistence.
  • db_username, db_password, db_port - The MySQL username, password, and the port, respectively.
  • persistence_handler_class - Name of the class of the custom implementation for persistence. This key is mandatory if you want to use custom persistence.
  • persistence_handler_class_path - The absolute path to the custom DB implementation (.rb file).
  • application_log_file_path - The absolute path to log the exceptions during the usage of the SDK.
  • log_in_console - To print the exceptions on the console screen, when set as "true".
  • sandbox - Boolean key to make API calls to the sandbox environment. The value true makes API calls to the sandbox. Default value is false.
  • access_type - Must be set as offline as the SDK does not support online OAuth client, now.
  • accounts_url - The domain-specific accounts URL from which you generate the tokens.
    This key is mandatory when the user is not in the "com" domain.
    For US:
    https://accounts.zoho.com
    For EU:
    https://accounts.zoho.eu
    For CN:
    https://accounts.zoho.com.cn
    For IN:
    https://accounts.zoho.in
  • api_base_url - The domain-specific API URL from which you make API calls. For users from domains other than the US, this key is mandatory.
    For US:
    https://www.zohoapis.com
    For EU:
    https://www.zohoapis.eu
    For CN:
    https://www.zohoapis.com.cn
    For IN:
    https://www.zohoapis.in
  • api_version - Represents the version of the CRM APIs. The value is v2.
  • current_user_email - The email ID of the current user. You must set this either in the configuration array or ZCRMSDK::RestClient::ZCRMRestClient.current_user_email = "current user email id".

Below is a configuration dictionary with all the keys. 

config_details = { 'client_id' => 'xxxxx', #mandatory
'client_secret' => 'xxxxxx', #mandatory
'redirect_uri' => 'https://www.zoho.com', #mandatory
'api_base_url' => 'https://www.zohoapis.com', #optional, default is https://www.zohoapis.com
'accounts_url' => 'https://accounts.zoho.com', #optional, default is https://accounts.zoho.com
'current_user_email' => 'abc@xyz.com', #mandatory (should be either set in config array or ZCRMSDK::RestClient::ZCRMRestClient.current_user_email = "current user email id" )
'api_version' => 'v2', #optional,default is v2
'sandbox' => 'false', #optional default is sandbox
'application_log_file_path' => "/Users/xxxx/Desktop/log.log", #optional, absolute path of log file
'log_in_console' => 'true', #optional default is false, to log on the console
'persistence_handler_class_path' => 'absolute/path/to/customClass.ruby', #absolute path to the custom db implementation
'persistence_handler_class' =>'classname', #name of the class
'token_persistence_path'=>'relativepath/to/zcrm_oauthtokens.txt', #for file persistence
'db_username' => 'username', #optional, default root
'db_password' => 'password', #optional, default ''
'db_port' => 'port_number', #optional, default 3306
}

Now that you have created and registered your app with Zoho, you must authenticate it. 
Pass the configuration dictionary in the method ZCRMRestClient.init(config) and authenticate your app.

3.c. Generating the tokens

As the V2 Zoho CRM APIs follow the OAuth2.0 protocol, it is mandatory to authorize the OAuth2.0 app before using the SDK functions.
You can generate an access token from a grant token.
You can generate the grant token in two ways based on the type of client.

For Self Client Applications
  • Go to Zoho Developer Console.
  • Select your Self Client.
  • Provide the necessary scopes separated by commas, along with the scope aaaserver.profile.READ.
  • Select the Time Duration from the drop-down. This is the time the grant token is valid for.
  • Provide a description for the scopes. Click GENERATE.
  • Copy the grant token.

For Web-based Applications

It is the responsibility of your client app to generate the grant token for the users trying to login.
Your Application's UI must have the Login with Zoho option to open the grant token URL of Zoho, which would prompt for the user's OAuth2.0 authorization.
Upon the successful login of the user, the grant token will be sent as a parameter to your registered redirect URL.

Generating an access token from the grant token
Use the below code snippet in your main class.

client = ZCRMSDK::OAuthClient::ZohoOAuth.get_client_instance
grant_token = 'grant_token'
client.generate_access_token(grant_token)
Note
  • The code snippet to generate the access token from the grant token is valid only once per grant token. If the grant token expires before you generate the access token, you must generate a new grant token only.
  • Generating access and refresh tokens is a one-time process. After the tokens are generated the first time, the SDK persists them based on the keys defined in the configuration dictionary, and refreshes the access token as and when required.

Step-4: Connect to Zoho CRM through the available methods
Here is a sample to get a specific user's details. You can find the code for this sample in the attachment.


The isTokenGenerated Method

def self.is_token_generate(user)
    tokens = ZCRMSDK::OAuthClient::ZohoOauth.get_persistence_instance.get_oauth_tokens(user)
    unless tokens.nil?
        return true
    end
    rescue Exception => e
        return false 
  end
You need to add this method to check if the access token has already been generated or not. It returns a Boolean value.
  • true - The access token has already been generated. 
  • false - The access token has not been generated previously, thus, it shifts the control to the code snippet that leads to access token generation.
For more sample codes, refer to our SDK guide.
We hope you found this post useful. Stay tuned for more!

Cheers!




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