Custom functions can satisfy business-specific requirements by letting you write the entire function from scratch. Once created, they can be used by all members in your organization.

Create a custom function

Use an existing custom function

Delete a custom function

Using app connections in your functions

Important note for Zoho app connections

Deluge statements and tasks

Create a custom function

1. Click the Logic tab on the left side of the builder.
   
   
2. Click Custom Functions.
   
3. Click +Custom Function.
   
   
4. Enter a name. Remember that the name must start with a letter or underscore and can only include alphanumeric characters and underscores.
   E.g: _discount_calculation_1, autofill_zipcode
5. Select a return type (output data type) and optionally specify the parameter (input) and its data type.
   

   Data Type	Description
   void	No value
   int	Integer value
   float	Decimal value
   string	Text
   bool	Either true or false
   date	Date value
   map	Key-value mapping
   list	List of values
   file	File object

   Note: 
   • The return type will be void by default.
   • The input data type cannot be void.
   • FILE is a unique data type that treats all files fetched from the web or cloud services (irrespective of file format) as file objects. Refer to Deluge documentation to learn more.
6. Click Create.
   
7. Write the code for your custom function. Refer to Deluge documentation to learn more.
   
   
   
8. Click Save.
   
9. To modify the custom function code, click the edit icon on the function. Any member in the organization can edit or delete a custom function in the organization.
   
   
   
   

The created function will now be available under Custom Functions in the Logic tab.

Use an existing custom function

1. Click the Logic tab on the left side of the builder.
   
2. Click Custom Functions. You can view the list of existing custom functions in your organization.
   
   
3. Drag and drop the function you want to use to the builder screen. A configuration window will open.
   
   
   
4. Configure the function by entering the input parameter(s) of the function.
   
5. Click Save.
   
6. You can edit the custom function data you configure by clicking the edit icon on the right side of the custom function. You can also delete it like other actions.
   
   

Delete a custom function

1. Click the Logic tab on the left side of the builder.
   
2. Click Custom Functions. You can view the list of existing custom functions in your organization.
   
3. On mouse over, the delete icon will appear. Click on it to delete the function.
   

If a custom function is deleted, all the flows using the function will be affected.

Using app connections in your functions

Zoho Flow allows you to use your app connections in custom functions by using the invokeURL task. This helps you to establish authentication with Zoho or third-party services to access data and integrate with them when using a function.
Learn more about the invokeURL task.

How to embed your app connections in an invokeURL task

1. Click My Connections on the left of the custom function console.
   
2. Find the app connection that you require from the list, then click View Details.
   If the connection doesn't already exist, you can create a new app connection by clicking Create Connection.
   
3. Copy the code snippet and paste it into your function to embed this connection.
   
4. You can also copy the Connection link name from the same box.
   

Note:
• Connection link names are unique names given to an app connection that can be used in invokeURL scripts to refer to a connection and authorize the connection with that app.
• Connection support is only currently available for the invokeURL task. We are working on supporting predefined integration tasks.

Important note for Zoho app connections

If you are already using any authtoken-based Zoho app connections in your invokeURL tasks, it is important that you modify them to OAuth-based connections immediately. All Zoho apps are migrating from authtoken-based authorization to OAuth-based authorization and existing authtoken-based connections will no longer work.

To update the connections:

1. Identify the Zoho app connection that you have embedded in your custom function using the invokeURL task.
   
2. Create a new OAuth-based connection for your Zoho app.
   
3. In the required invokeURL task, remove the authtoken parameter and use the new connection. Follow the steps in the previous section to embed the new connection in your existing invokeURL task.
   

For example, in the following function, an authtoken is used to establish a connection to Zoho Books:

After creating an OAuth connection for Zoho Books, the script can be modified to embed the newly created connection.

Deluge statements and tasks

These are blocks of code available on the left of the custom function coding screen. Drag and drop them onto the coding area and enter the required data.

Basic

Condition

Notifications

Integrations

Collection

Basic

Set Variable

Creates a variable with the given value that can be accessed within the action

For example: 

Every time the quantity value is changed, the value of the price will be modified

Add Comment

Adds comment to make your code understandable by others

For example: 

Any data that is after '//' will be considered a comment

info

Prints the value of specified parameters as the function output in the history log

For example: 

This prints the customer names in the history log

Condition

if

Checks for a condition. If the condition is true, it performs the specified action.

For example:

1. if (client_title == "CEO")
   
2. {
   
3. client_type = "premium";
   
4. }

This checks if the client title is CEO. If it is true, the client type is set to premium.

else if

Executes when the previous if statement is false and this statement is true

For example:

1. if (client_title == "CEO")
   
2. {
   
3. client_type = "premium";
   
4. }
   
5. else if (client_title == "Admin")
   
6. {
   
7. client_type = "standard";
   
8. }

When the client title is not CEO, but is Admin, the client type is set to standard

else

Executes when both if and else if statements fail

For example:

1. if (client_title == "CEO")
   
2. {
   
3. client_type = "premium";
   
4. }
   
5. else if (client_title == "Admin")
   
6. {
   
7. client_type = "standard";
   
8. }
   
9. else
   
10. {
    
11. client_type = "regular";
    
12. }

When neither if nor else if conditions hold true, the client type is set to regular.

Notifications

Send mail

Sends an email to the specified recipients

For example:

Integrations

webhook

Creates a webhook subscription for another application

1. param = Collection("TestParam":"TestValue");
   
2. header = Collection("Content-type":"application/json");
   
3. testWebhook = invokeurl
   
4. [
   
5. url :"https://requestb.in/1ckt5a31%22"
   
6. type: POST
   
7. parameters: param
   
8. headers: header
   
9. ];
   

Learn more

Collection

create collection

Creates a map or a list depending on the input elements specified

1. students = Collection ();
   

insert

Adds elements to the specified collection

For example: 

Adds the given names to the students list

For example: 

Adds the given key-value pairs to the map

get

Fetches a particular element from the specified collection

For example: 

Fetches the value at index 6 from the students list

For example: 

Fetches the value mapped with the key 'name' in the students map

update

Updates the specified collection

For example: 

Updates the value in the second element of the list to 'Micheal'

For example: 

Updates the value in the key 'grade' to 9

for each element

Performs the task for each element in the specified collection

For example:

1. for each student_mail in students
2. {
3. myMessage = "Welcome to the students sports club. Please assemble at 9:00 am in the basketball court tomorrow.";
4. sendmail
5. [
6. from :zoho.loginuserid
7. to :student_mail
8. subject :"Invitation to Sports club"
9. message :myMessage
10. ]
11. }

For every student email address available in the list, the mail will be sent

For example:

1. name = collection();
2. name.insert("First Name":"Emma", "Middle Name":"Marley", "Last Name":"Becker");
3. Fullname = "";
4. for each element in name
5. {
6. Fullname += (element+" ");
7. }

This function concatenates every value in the map. The output value of this function will be 'Emma Marley Becker'.

Note: Date-time fields must be converted into string functions before being used in custom functions or data mapping.

Sample code:

This helps transform one date format into another and converts it into a string function.

1. string formatDate(string myDate, string fromFormat, string toFormat)
2. {
3. fromDate = myDate.toTime(fromFormat);
4. dateStr = fromDate.toString(toFormat);
5. return dateStr;
6. }

Create a custom function with the above code. Specify the following input parameters:

• myDate - Date field from the previous step
  
• fromFormat - Date format of the previous step
  
• toFormat - Date format of the next step
  

For example, if you are creating this custom function between a MailChimp trigger and a Zoho Creator action, map myDate to the date field from MailChimp. fromFormat will be MailChimp's date format and toFormat will be Zoho Creator's date format.