Merchant Integration Documentation(Backend GoLang Auth SDK)

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A. OTPLessAuth Dependency

install Below dependency in your project's

go get github.com/otpless-tech/otpless-auth-sdk@latest

you can also get latest version of dependency at https://pkg.go.dev/github.com/otpless-tech/otpless-auth-sdk/pkg

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B. OTPLessAuth

The OTPLessAuth pkg provides methods to integrate OTPLess authentication into your GoLang backend application. This documentation explains the usage of the class and its methods.

Methods:

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1. decodeIdToken

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This method help to resolve idToken(JWT token) which is issued by OTPLess which return user detail from that token also this method verify that token is valid, token should not expired and issued by only otpless.com

Method Signature:

DecodeIDToken(idToken, clientID, clientSecret, audience string)

Method Params:

Params	Data type	Mandatory	Constraints	Remarks
idToken	String	true		idToken which is JWT token which you get from OTPLess by exchange code API
clientId	String	true		Your OTPLess Client Id
clientSecret	String	true		Your OTPLess Client Secret
audience	String	false		None

Return

Return: Object Name: UserDetailResult

2. VerifyCode

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This method help to resolve token which is issued by OTPLess which return user detail from that token also this method verify that token is valid, token should not expired and issued by only otpless.com

Method Signature:

VerifyCode(code, clientID, clientSecret)

Method Params:

Params	Data type	Mandatory	Constraints	Remarks
code	String	true		code which you get from OTPLess
clientId	String	true		Your OTPLess Client Id
clientSecret	String	true		Your OTPLess Client Secret

Return

Return: Object Name: UserDetailResult

3. VerifyAuthToken

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This method help to resolve token which is issued by OTPLess which return user detail from that token also this method verify that token is valid, token should not expired and issued by only otpless.com

Method Signature:

VerifyAuthToken(token, clientID, clientSecret string)

Method Params:

Params	Data type	Mandatory	Constraints	Remarks
token	String	true		token which you get from OTPLess
clientId	String	true		Your OTPLess Client Id
clientSecret	String	true		Your OTPLess Client Secret

Return

Return: Object Name: UserDetailResult

userDetail := UserDetailResult{
    Success:     true,
    AuthTime:  1697473071,
    Email:       "dev****@gmail.com",
    Name:        "Dhaval From OTP-less",
    PhoneNumber: "+9193*****",
    country_code: "+91",
    national_phone_number: "95******",
}

UserDetail Object Fields:

success (boolean): This will be true in case of method successfully performed operation.
> authTime (Long, required): The time when authentication was completed.
> phoneNumber (String, required): The user's phone number.
> countryCode (String, required): The country code of user's phone number.
> nationalPhoneNumber (String, required): The user's phone number without country code.
> email (String, required): The user's email address.
> name (String, required): The user's full name.

4. Generate Magic link

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The Authorization Endpoint initiates the authentication process by sending a magic link to the user's WhatsApp or email, based on the provided contact information. This link is used to verify the identity of the user. Upon the user's action on this link, they are redirected to the specified URI with an authorization code included in the redirection.

Method Signature:

GenerateMagicLink(mobileNumber, email, clientID, clientSecret, redirectUri, channel string) (*MagicLinkResponse, error)

Method Params:

Params	Data type	Mandatory	Constraints	Remarks
channel	String	false	if no channel given WHATSAPP is chosen as default	WHATSAPP/SMS
mobile_number	String	false	At least one required	The user's mobile number for authentication in the format: country code + number (e.g., 91XXXXXXXXXX)
email	String	false	At least one required	The user's email address for authentication.
redirect_uri	String	true		The URL to which the user will be redirected after authentication. This should be URL-encoded
clientId	String	true		Your OTPLess Client Id
clientSecret	String	true		Your OTPLess Client Secret

Return

Return: Object Name: RquestIds

&{RequestIds:[{Type:MOBILE Value:c36b678aef104691b15f93910acfee48 DestinationUri:https://wa.me/91971***XX**} {Type:EMAIL Value:39250d56e8da4f4cb86224929bf76a2d}]}

Error case:

success (boolean): This will be false. The method is failed to perform.
errorMessage (String): The message contains error information.

C. OTP class

These methods enable you to send, resend and verify OTP.

Methods:

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1. Send OTP

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Method Signature:

SendOTP(req SendOTPRequest, clientID, clientSecret string) (*SendOTPResponse, error)

Method Params:

Params	Data type	Mandatory	Constraints	Remarks
phoneNumber	String	true		Mobile Number of your users
email	String	true		Mail Id of your users
orderId	String	false		An Merchant unique id for the request.
expiry	Int	false		OTP expiry in sec
hash	String	false		An Hash will be used to auto read OTP.
clientId	String	true		Your OTPLess Client Id
clientSecret	String	true		Your OTPLess Client Secret
otpLength	Integer	false	4 or 6 only allowed	Allowes you to send OTP in 4/6 digit. default will be 6 digit.
channel	String	false	SMS/WHATSAPP/ALL (if no channel given SMS is chosen as default)	Allowes you to send OTP on WhatsApp/SMS/Both. default will be SMS

Return

Return: Object Name: SendOTPResponse

{
  "orderId": "Otp_ED5F709E1C6B41EB8C0595C7968354EB"
}

2. Resend OTP

Method Signature:

    ResendOTP(orderID, clientID, clientSecret string) (*ResendOTPResponse, error)

Method Params:

Params	Data type	Mandatory	Constraints	Remarks
orderId	String	true		An Merchant unique id for the request.
clientId	String	true		Your OTPLess Client Id
clientSecret	String	true		Your OTPLess Client Secret

Return

Return: Object Name: ResendOTPResponse

{
  "orderId": "DP0000111"
}

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3. Verify OTP

Method Signature:

    VerifyOTP(orderID, otp, email, phoneNumber, clientID, clientSecret string) (*VerifyOTPResponse, error)

Method Params:

Params	Data type	Mandatory	Constraints	Remarks
email	String	true		An email on which OTP has been sent.
phoneNumber	String	true		An phone number on which OTP has been sent.
orderId	String	true		An Merchant unique id for the request.
otp	String	true		OTP value.
clientId	String	true		Your OTPLess Client Id
clientSecret	String	true		Your OTPLess Client Secret

Return

Return: Object Name: VerifyOTPResponse

• reason (String): The will be errorMessage in case of OTP doesn't verified

{
  "isOTPVerified": true
}

Example of usage

package main

import (
	"fmt"

	otplessAuthSdk "github.com/otpless-tech/otpless-auth-sdk"
)

func main() {
	clientID := "your_client_id"
	clientSecret := "your_client_secret"
	code := "some_code"

	result, err := otplessAuthSdk.VerifyCode(clientID, clientSecret, code)

	if err != nil {
		fmt.Println("Error:", err)
		return
	}

	fmt.Println("Result:", result)
}

This method allows you to decode and verify OTPLess ID tokens and retrieve user information for integration into your backend GoLang application.