WHMCS Accounting Software Electronic Invoice Integration
Electronic Invoicing is spreading around the world and is quickly becoming mandatory in many countries. Billing Extension integrates Italian and Slovene E-Invoicing with WHMCS but can also give a precious help with other countries.
We would like to integrate all countries but e-invoice differs enormously from country to country due to diffrent regulations and technological aspects. Let us put it into perspective. Integrating Italian e-invoice took us 4 months work. Keeping it functional is a process that never stops.
It is prohibitive for us to go through the same thing for tens of different countries. The good news is that there is a common thread through most of electronic invoicing implementations.
Instead of leaving non-Italian and non-Slovenian customers alone dealing with electronic invoicing, we came up with the idea of including in our module a plugin that provides all data you need to integrate WHMCS with any electronicing invoicing platform.
We understand that the idea of completing the integration on your own is daunting but you just need to take care of the final step. From our experience a big part of the job is:preparing, validating and retrieving data from WHMCS.
- Preparing, validating and retreiving billing data from WHMCS
- Implementing billing concepts that WHMCS is not aware of
Billing Extension combined with this plugin already gives you everything you need. Not to mention that this can also be used to integrate WHMCS with your accounting software. Keep reading to learn more.
Begin by visiting Addons > Billing Extension > Settings and click "plus" icon to activate WebService.
Once done, go back to Settings and expand the newly added section. Here you find WebService configuration. At the moment of writing this, it only has one parameter named Token.
This randomly generated string is used to establish a secure connection for transmissions of data. Press the orange button to generate the token and save.
We prepared this PHP script with comments to show you how easily you can interact with our web service. We used the same principle WHMCS External API. In essence send a curl() request and receive the response in json array.
Authentication requires two parameters. At some point we were also thinking of using OAuth 2.0 but it was a bit overkill.
|$URL||URL to the root of WHMCS that can be found on Setup > General Settings > General > WHMCS SystemURL. Trailing slash "/" is required.||Required|
|$Token||It must be the same of Addons > Billing Extension > Settings > WebService > Token||Required|
Use this command to retrieve from WHMCS billing details enriched and validated by Billing Extension. Multiple filters are available.
|start||The starting date for the returned results. Supports YYYY-MM-DD dates, integers (5 returns last 5 days) and keywords (yesterday, month to date, last year etc.). Leave empty to get all invoices||Optional|
|end||If “start“ has been specified in date format, “end“ can be used to select invoices between a range of dates (eg. start 2019-06-01 end 2019-06-15). The only supported format is YYYY-MM-DD||Optional|
|invoicenum||Select the invoice with this specific Invoice Number. If in use, “start“ and “end“ values are ignored. Can't be used together with “invoiceid“||Optional|
|invoiceid||Select the invoice with this specific Invoice ID. Must be an integer. If in use, “start“ and “end“ values are ignored. Can't be used together with “invoicenum“||Optional|
|doctype||“Invoice“ and “CreditNote“ return invoices and credit notes respectively. If empty, both types are returned||Optional|
|ClientData||UserID||User ID (tblclients.id)|
|ClientData||ClientData||Firstname (eg. “Jack“)|
|ClientData||Lastname||Lastname (eg. “Black“)|
|ClientData||ClientName||Firstname and lastname separated by space (eg. “Jack Black“)|
|ClientData||State||State, region, province|
|ClientData||Country||Two-letter ISO country code (eg. IT, DE, ES)|
|ClientData||Currency||Currency ID of selected customer|
|ClientData||TaxExempt||“1“ is tax exempt. “0“ is not tax exempt|
|ClientData\CustomFields||id||Client custom field ID (tblcustomfields.id)|
|ClientData\CustomFields||fieldname||Client custom field name (eg. VAT Number)|
|ClientData\CustomFields||value||Client custom field value|
|ClientData\Europe||MemberState||Two-letter ISO country code (eg. IT, DE, ES)|
|ClientData\Europe||Region||Mostly “Europe“ but can also be equal to “South-America“, “Africa“ etc. for outermost regions and overseas territories of European Union|
|ClientData\Europe||MonetaryUnion||true/false (eg. Italy “true“, Denmark “false“)|
|ClientData\Europe||VIES||true/false. If “true“ the selected customer is an Intra-EU company registered on VIES|
|DocData||Type||“Invoice“ or “CreditNote“|
|DocData||ID||Document ID (tblinvoices.id)|
|DocData||Num||Document Number (eg. 2019-150)|
|DocData||Status||Invoice status (“Paid“, “Draft“, “Unpaid“ etc.)|
|DocData||Date||Date in YYYY-MM-DD format|
|DocData||DueDate||Due date in YYYY-MM-DD format|
|DocData||DatePaid||Date/time when invoice has been paid in YYYY-MM-DD hh:mm:ss format|
|DocData||Subtotal||Subtotal. 2 decimal places. Dot as the decimal separator|
|DocData||Credit||Credit. 2 decimal places. Dot as the decimal separator|
|DocData||Tax||Level 1 Tax. 2 decimal places. Dot as the decimal separator|
|DocData||Tax2||Level 2 Tax. 2 decimal places. Dot as the decimal separator|
|DocData||TaxRate||Level 1 Tax Rate. 2 decimal places. Dot as the decimal separator|
|DocData||TaxRate2||Level 2 Tax Rate. 2 decimal places. Dot as the decimal separator|
|DocData||PaymentMethod||Payment gateway (eg. paypal)|
|DocData\Items||ID||Invoice item ID (tblinvoiceitems.id)|
|DocData\Items||Type||“Setup“, “Hosting“, “Domain“, “Upgrade“, “Item“, “Addon“, “PromoHosting“, “DomainGraceFee“, “LateFee“ etc.|
|DocData\Items||RelID||ID of the related product/service, domain, addon, billing item etc.|
|DocData\Items||Description||Description (eg. Renew Domain example.com)|
|DocData\Items||Amount||Invoice line amount. 2 decimal places. Dot as the decimal separator|
It is worth noting that ClientData values come from Invoice Snapshots therefore they're safe to use of billing purposes. Moreover such values are trimmed to remove whitespace from both ends of strings.
We made our WebService user-friendly. In practical terms when there's something wrong in your API request, WebService provides clear details about the error directly in the json response. Such errors are not cryptic but give a full description about what went wrong.
When it comes to dates, the WebService supports special keywords that help you filtering records by predefined intervals listed in the table below. Monday is considered the first day of the week and the provided descriptions assume that current date is Saturday 2019-06-15.
|Last 7 days||Select from 2019-06-08 to 2019-06-15|
|Last week||Select from 2019-06-10 to 2019-06-16|
|Week to date||Select from 2019-06-10 to 2019-06-15|
|Month to date||Select from 2019-06-01 to 2019-06-15|
|Previous month||Select from 2019-05-01 to 2019-05-31|
|Year to date||Select from 2019-01-01 to 2019-05-15|
|Last year||Select from 2018-01-01 to 2018-12-31|
|All||Select all records|