Using ‘Value Expression’ in OpenBots Documents.
This guide can help you create simple expressions that combine and manipulate data extracted from documents into what you exactly need. The Expressions
using
Liquid is a powerful templating language that allows you to create dynamic output by combining fields extracted from a document.
What is Liquid templating language?
Liquid is a templating language that allows you to insert dynamic content in your output. In our system, Liquid can be used to process and format data extracted from Documents. For example, you can combine the first name, last name, and gender fields to create a personalized salutation.
Basic Syntax of Liquid
Liquid templates are made up of tags, objects, and filters:
1. Tags: Tags are used to create logic or control flow in your templates
They are enclosed within `{% %}`.
– Example: `{% if condition %}…{% endif %}`
2. Objects: Objects are used to display content and are enclosed within `{{ }}`. They represent the data you want to insert into the template.
– Example: `{{ FirstName }}`
3. Filters: Filters are used to modify the output of an object. They are applied using the pipe `|` character.
– Example: `{{ FirstName | capitalize }}`
Step-by-Step Guide to Creating Expressions
1. Combining Fields
Let’s say you have extracted the following fields from a Document:
– `FirstName = “John”`
– `LastName = “Doe”`
– `Gender = “Male”`
You can combine these fields to create a full name with a salutation using the following expression:
{% if Gender == “Male” %}
Mr. {{ FirstName }} {{ LastName }}
{% elsif Gender == “Female” %}
Ms. {{ FirstName }} {{ LastName }}
{% else %}
{{ FirstName }} {{ LastName }}
{% endif %}
This expression checks the gender and adds the appropriate salutation before the name.
2. Using Filters
Filters allow you to modify the extracted data. Here are some common filters:
– capitalize: Capitalizes the first letter of a string.
– Example: `{{ FirstName | capitalize }}`
– upcase: Converts a string to uppercase.
– Example: `{{ LastName | upcase }}`
– downcase: Converts a string to lowercase.
– Example: `{{ LastName | downcase }}`
For instance, if you want to display the full name in uppercase, you can use:
{% if Gender == “Male” %}
MR. {{ FirstName | upcase }}
{{ LastName | upcase }}
{% elsif Gender == “Female” %}
MS. {{ FirstName | upcase
}} {{ LastName | upcase }}
{% else %}
{{ FirstName | upcase }}
{{ LastName | upcase }}
{% endif %}
3. Conditional Logic
Liquid supports conditional statements, allowing you to create expressions based on certain conditions. Here’s a simple example:
{% if Age > 18 %}
Adult
{% else %}
Minor
{% endif %}
This expression checks if the extracted `Age` field is greater than 18 and outputs “Adult” if true, otherwise “Minor”.
4. Iterating Over Collections
If your extracted data includes lists or arrays, you can loop over them using the `for` tag:
{% for item in items %}
{{ item }}
{% endfor %}
This will iterate over each item in the `items` array and output it.
Practical Examples
Example 1: Combining Name and Address
Suppose you have the following fields extracted:
– `FirstName = “Jane”`
– `LastName = “Smith”`
– `Street = “123 Main St”`
– `City = “Anytown”`
– `State = “CA”`
– `ZipCode = “12345”`
You can create an expression to combine these into a formatted address:
{{ FirstName }} {{ LastName }}
{{ Street }}
{{ City }}, {{ State }} {{ ZipCode }}
This will output:
Jane Smith
123 Main St
Anytown, CA 12345
Example 2: Conditional Output Based on Document Type
If your Document extraction identifies the type of document, you can use conditional logic to format the output accordingly:
{% if DocumentType == “Invoice” %}
Invoice Number: {{ InvoiceNumber }}
Date: {{ Date }}
Total: ${{ Total }}
{% elsif DocumentType == “Receipt” %}
Receipt Number: {{ ReceiptNumber }}
Date: {{ Date }}
Amount Paid: ${{ AmountPaid }}
{% endif %}
Tips for New Users
– Start simple: Begin with basic expressions and gradually introduce more complex logic as you become comfortable with Liquid.
– Test frequently: Test your expressions with actual data to ensure they produce the desired output.
– Use Liquid documentation:
Refer to the [ Liquid documentation ] for more details on tags, filters, and other features.
| Category | Function Name | Description | Sample Usage |
|---|---|---|---|
| Math | abs | Returns the absolute value of a number. | {{ abs(-5) }} → 5 |
| Math | ceil | Rounds a number up to the nearest integer. | {{ ceil(4.3) }} → 5 |
| Math | floor | Rounds a number down to the nearest integer. | {{ floor(4.8) }} → 4 |
| Math | round | Rounds a number to the nearest integer or specified precision. | {{ round(4.56, 1) }} → 4.6 |
| Math | max | Returns the maximum value from a list of numbers. | {{ max(1, 2, 3) }} → 3 |
| Math | min | Returns the minimum value from a list of numbers. | {{ min(1, 2, 3) }} → 1 |
| String | lower | Converts a string to lowercase. | {{ lower("HELLO") }} → "hello" |
| String | upper | Converts a string to uppercase. | {{ upper("hello") }} → "HELLO" |
| String | replace | Replaces all occurrences of a substring with another string. | {{ replace("Hello world", "world", "Scriban") }} → "Hello Scriban" |
| String | split | Splits a string into an array based on a delimiter. | {{ split("a,b,c", ",") }} → ["a", "b", "c"] |
| String | substring | Extracts a substring from a string. | {{ substring("hello", 1, 3) }} → "ell" |
| Array | size | Returns the number of elements in an array. | {{ size([1, 2, 3]) }} → 3 |
| Array | reverse | Reverses the order of elements in an array. | {{ reverse([1, 2, 3]) }} → [3, 2, 1] |
| Array | sort | Sorts an array in ascending order. | {{ sort([3, 1, 2]) }} → [1, 2, 3] |
| Array | first | Returns the first element of an array. | {{ first([1, 2, 3]) }} → 1 |
| Array | last | Returns the last element of an array. | {{ last([1, 2, 3]) }} → 3 |
| Date | date.now | Returns the current date and time. | {{ date.now }} → "2024-08-13T12:00:00Z" |
| Date | date.format | Formats a date according to a specified format. | {{ date.format(date.now, "%Y-%m-%d") }} → "2024-08-13" |
| Date | date.add_days | Adds a number of days to a date. | {{ date.add_days(date.now, 5) }} → "2024-08-18" |
| Date | date.parse | Parses a string into a date using a specified format. | {{ date.parse("2024-08-13", "%Y-%m-%d") }} → date object |
| Control Flow | if | Executes a block of code if a condition is true. | {% if condition %} ... {% endif %} |
| Control Flow | for | Iterates over each item in a collection or array. | {% for item in collection %} ... {% endfor %} |
| Control Flow | while | Repeats a block of code while a condition is true. | {% while condition %} ... {% endwhile %} |
| Utility | typeof | Returns the type of a value. | {{ typeof(123) }} → "number" |
| Utility | Outputs a value to the console or output. | {{ print("Hello World") }} → "Hello World" |
