read-msg

Use read-msg to read a specific key from the top level of the message data body, or to read the data body itself if a key is not provided. In reading the value, this function enforces its corresponding Pact type, such as string, integer, boolean, list, or object.

Basic syntax

To read the value for a specified key from the body of a message, use the following syntax:

(read-msg key)

To read the complete message data body, use the following syntax:

(read-msg)

Arguments

Use the following argument to specify the key to be read from the top level of the message data body using the read-msg Pact function.

Argument	Type	Description
key	string	Specifies the key to be read from the message data body (optional). If you don't provide this argument, the function reads the entire data body.

Return value

The read-msg function returns the value corresponding to the specified key from the message data body, or the entire data body if no key is provided. The data type for the return is its corresponding Pact type.

Example

The following example demonstrates how to use the read-msg function in a Pact script. This example reads the from and to keys from the data body of a message as strings and the amount as a decimal:

(defun exec ()
   (transfer (read-msg "from") (read-msg "to") (read-decimal "amount")))

This example illustrates how to use the read-msg function to extract specific values from the body of a message for further processing in a Pact script.