AuthorizeNet_AIM_9 - Payment processing tag for Lasso Professional 9 and the Authorize.Net AIM v3.1 payment processing gateway

The project AuthorizeNet_AIM_9 and its source files are hosted on GitHub.


This method is a conversion of the AuthorizeNet_AIM payment processing method from Lasso 8 to Lasso 9.

This method has one required parameter, -AIMParams, and two optional parameters, -testdeveloper and -testrequest.

-AIMParams is an unnamed map of name/value pairs representing the parameters to be passed to Authorize.Net.

-testdeveloper is a boolean that when TRUE submits a test transaction to Authorize.Net's "test" URL. Default is FALSE.

-testrequest is a boolean that when TRUE submits a test transaction request to the designated URL ("test" or "secure") as set in the method configuration or by the -testdeveloper keyword parameter. Default is FALSE.

This method returns a value which is either a string or a map.

  • If the returned value is a string, the string is a plain text error message returned by Authorize.Net indicating that you have not properly configured the Authorize.Net Merchant Interface or this method's settings.
  • If the returned value is a map, it contains the key/value pairs of non-empty parameters in the response returned by the Authorize.Net gateway.

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It is highly recommend to store the AuthorizeNet_AIM_9 type in a location on your web server that cannot be served, preferably outside of your web root. You do not want your login or transaction key to be served as a plain text file.

1. Configure

Configuration includes:

  • configuring the Authorize.Net website Merchant Interface,
  • setting values in this method, and
  • passing values into this method as a map of key/values.

Authorize.Net Merchant Interface

In the Authorize.Net Merchant Interface Account > Settings > API Login ID and Transaction Key, obtain your transaction key.

Edit this method by entering your transaction key, and saving the file.

Next configure the response delimiter character, under Account > Settings > Direct Response.

Use a pipe and no encapsulation characters:

Delimited Response (X) Yes  ( ) No
Default Field Separator | (pipe)  or [ ]
Field Encapsulation Character [blank] or  [ ]

If you do not use the above settings, then you must change the corresponding values as defined elsewhere in this method.

Setting values in this method or by passing in parameters

You can choose to either set configuration values in this method below, or pass them in as values in the map of AIM parameters. Any values passed into this method will override their corresponding values entered below.

In your page that calls [AuthorizeNet_AIM_9], build a map of parameters to send to the method.

var('AIMParams') = map(
    'x_first_name'  = $first_name,
    'x_last_name'   = $last_name,
    'x_amount'              = $amount,
... and so on...)

2. Set a variable to the method

When calling [AuthorizeNet_AIM_9], store the results in a variable. This will allow you to easily code logic in your page to take appropriate action based on the results (Response Code, etc.) from Authorize.Net.

var('aim_results') = AuthorizeNet_AIM_9($AIMParams)

Optionally, use the following following parameters.

-testdeveloper=TRUE submits a test transaction to Authorize.Net's "test" URL. Default is FALSE.

-testrequest=TRUE submits a test transaction request to the designated URL ("test" or "secure") as set in the method configuration or by the -testdeveloper keyword parameter. Default is FALSE.

The following sends a map of parameters to the method, which posts the parameters to Authorize.Net's test server as a test transaction request.

var('aim_results') = AuthorizeNet_AIM_9(

3. Sample page logic

// evaluate results and make appropriate decisions
if($aim_results->find('x_response_code') == '1')
    // transaction approved
    // transaction failed
            //  declined
            //  transaction processing error
            //  held for review
            //  undefined error

4. Sample message

I recommend displaying a simple error message "Your request could not be processed. Please contact us at _____ during normal business hours." Don't encourage users to try again because it will just frustrate them, or possibly cause much worse problems (multiple payments, trigger an over limit event, trigger a fraud alert with the card issuer, etc.). And in the case of actual fraud, you don't want to tip off the fraudster of why the transaction was declined.

$sample_msg->append('Thank you, ' + $aim_results->find('x_first_name')
    + '!  You have personally enriched me by $'
    + $aim_results->find('x_amount') + '.')

5. Custom labels

You can add merchant-defined results labels to #aimresultlabels, and access them after they are echoed by Authorize.Net.

6. Summary

Here is a code sample that sends an authorize-only transaction to the Authorize.Net test server.

var('AIMParams') = map(
    'x_card_num'='5424000000000015',    // dummy CC#
    'x_exp_date'='1220',                // December 2020

var('results') = AuthorizeNet_AIM_9($AIMParams, -testdeveloper=true)

See the comments embedded in the method's code for proper configuration.

For rapid testing:

  • Copy the files and AuthorizeNet_AIM_9.lasso to your web server.
  • Configure settings in both files accordingly. The settings in the latter override the former.
  • Save and load AuthorizeNet_AIM_9.lasso to see the results.

Additional eCommerce Resources

The following information does not constitute an endorsement, warranty or guarantee of service. This information is provided for the sake of comparison. These are the lowest fees I have found over the years.

For further information on developing for AIM, download the AIM Guide.

You can sign up for a developer sandbox account, or you can have the client purchase their own Authorize.Net payment gateway account and create a "webmaster" user that has the required access.

In addition to this method, the following are requirements.

  1. Dedicated IP for SSL (~$10/month).
  2. SSL.
  3. Secure certificate (starting at $10/year from
  4. Merchant account that accepts payments over the Internet. Some brick and mortar retailers already have a merchant account, so sometimes it is easier to add this feature to their existing merchant account. If you need a merchant account, you can support the continued development of the AuthorizeNet_AIM_9 method using my referral link. As of May 28, 2014, the merchant account costs $8.95/month (for a statement fee), plus 2.14% of the transaction amount and 24¢ per transaction. Everything else is free.
  5. payment gateway (an Authorize.Net account, for example). I am an Authorize.Net account reseller. You can support the continued development of the AuthorizeNet_AIM_9 method by following my reseller link. As of May 28, 2014, the cost is $17.95/month, plus $99.00 account setup, plus $0.10 per transaction.

I am available as a consultant for ecommerce solutions. Please visit Services for more information.

Notes and Acknowledgments


This version has not been tested against an actual Authorize.Net gateway account. It has been tested against a developer test account only. Please let me know if you perform any tests against an actual Authorize.Net gateway account and the results of your tests.

Modified to work with Lasso 9. Thanks to Kyle Jessup for the void tip and LassoSoft for the Enigma Machine code converter (online test version has been offline since at least September 4, 2012 ).

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Updates, suggestions and comments regarding this article may be sent to Steve Piercy, [email protected] or comment using Disqus.

Written by Steve Piercy in Lasso on Tue, Sep 6, 2011.
Last modified: Tue, Jun 3, 2014
Tags: AuthorizeNet_AIM_9, Lasso, eCommerce, payment gateway


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