The document summarizes the FreshBooks API for creating and managing invoices, clients, estimates, expenses, and payments. It provides examples of XML requests and responses, describes how to authenticate and make requests to the API, and notes resources for client libraries and sample code.

1. The
API

2. How It Works
XML Request:
Invoice.list
POST POST POST POST POST POST POST POST POST
FreshBooks
You XML Response:
Invoices

3. What a Request Looks Like
<request
method="[RESOURCE].[METHOD]">
[parameters]
</request>
Some Resources Some Methods
Invoice Create
Clients Get
Estimate Update
Expense List
Payment Delete

4. Authentication
Post to Here
Your Credentials

5. Sending a Request
curl -u b6b5d45904881a749de87656699933ee:X
https://darthvader.freshbooks.com/api/2.1/xml-in -d
'<request
method="invoice.create">
<invoice>
<client_id>2</client_id>
<lines>
<line>
<name>Power
converters</name>
<unit_cost>35.00</unit_cost>
<quantity>3</quantity>
</line>
</lines>
</invoice>
</request>'

6. What a Successful
Response Looks Like
<!-­‐-­‐?xml
version="1.0"
encoding="utf-­‐8"?-­‐-­‐>
<response
xmlns="http://www.freshbooks.com/api/"
status="ok">
<invoice_id>115236</invoice_id>
</response>

7. What a Failed
Response Looks Like
<!-­‐-­‐?xml
version="1.0"
encoding="utf-­‐8"?-­‐-­‐>
<response
xmlns="http://www.freshbooks.com/api/"
status="fail">
<error>Invalid
value
for
field
'client_id'.
Client
does
not
exist.</error>
<code>40060</code>
<field>client_id</field>
</response>

8. Client Libraries
refreshbooks ruby-freshbooks
More resources & sample code at
http://developers.freshbooks.com

9. Here’s a Google Chrome Extension for
Experimenting with our API
http://developers.freshbooks.com/helper-libraries/