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Matchers: Empowering Variants

Matchers are essential building blocks in deco that play a pivotal role in empowering Variants. They allow you to evaluate specific conditions and segment your audience based on various criteria. By leveraging Matchers, you can create personalized and dynamic experiences for your users. When you create a new Matcher Block you may call it a Segment.

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Understanding Matchers

In deco, Matchers are created using functions within your site’s code. They are powerful tools that enable you to define conditions and evaluate whether a user belongs to a particular segment. Matchers serve as the foundation for targeting specific user groups and personalizing content based on their characteristics or behaviors. Standard Matchers are readily available in deco and cover a range of common conditions such as user traits, date and time, device type, geographic location, and random selection (A/B testing). These predefined Matchers offer flexibility and allow you to customize content variations based on these conditions. However, the power of Matchers extends beyond the standard options. deco provides the capability to create custom Matchers to meet the specific needs of your business. With custom Matchers, you can extend deco’s functionality to integrate external data sources, such as fetching data from a Salesforce ERP system, and then use that data to determine the segment to which a user belongs.

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Native Matchers

MatcherCommon Use CasesSticky
Random MatcherA/B test your page with 50% of traffic.session
Cron MatcherChange a page every Friday between 10 AM and 11 AM.none
Date MatcherCreate a Black Friday page / Schedule banners to appear at specific dates and times.none
Device MatcherShow a different page based on the user’s device.none

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Developing a new Matcher

In your repository, matchers are located within the matchers folder, similar to sections and loaders. Let’s create a new matcher called MyMatcher.ts to illustrate the process. The signature of our matcher will follow this structure: 
import { MatchContext } from "deco/blocks/matcher.ts";

export interface Props {
}

/**
 * @title My Matcher
 */
export default function MyMatcher(
  props: Props,
  ctx: MatchContext,
) {
  return true;
}
In the example above, the MyMatcher function accepts props as the input, allowing you to pass any necessary data to the matcher. Additionally, it receives a ctx object of type MatchContext, which contains the request information. You have the flexibility to perform any desired operations within the matcher function and return a boolean value based on the evaluation. Let’s take a look at the MatchDate example from the deco library: 
/**
 * @titleBy start
 */
export interface Props {
  /**
   * @format date-time
   */
  start?: string;
  /**
   * @format date-time
   */
  end?: string;
}

/**
 * @title Date Matcher
 */
const MatchDate = (props: Props) => {
  const now = new Date();
  const start = props.start ? now > new Date(props.start) : true;
  const end = props.end ? now < new Date(props.end) : true;
  return start && end;
};

export default MatchDate;
In this example, the MatchDate function serves as a Matcher. It accepts props as input, which includes start and end properties. The function evaluates whether the current date falls within the specified date range. If no start or end value is provided, it defaults to true. The MatchDate function returns a boolean value based on the evaluation. Matchers can also have a “sticky” behavior, which is particularly useful for A/B testing scenarios. To make a Matcher sticky on the user’s session, you can export a constant named sticky with the value "session", as shown below: 
export const sticky = "session";
Here is an example of the MatchRandom implementation using the sticky session feature: 
/**
 * @title ABTest {{{percentage traffic}}}
 */
export interface Props {
  traffic: number;
}

// Once selected, the session will reuse the same value
export const sticky = "session";

/**
 * @title Random Matcher
 */
const MatchRandom = ({ traffic }: Props) => {
  return Math.random() < traffic;
};

export default MatchRandom;
In the MatchRandom example, the matcher function MatchRandom accepts traffic as a prop, representing the percentage of traffic that should match the condition. By generating a random number between 0 and 1, the function determines whether the generated value is less than the specified traffic percentage. The Matcher returns true or false based on this evaluation. Matchers provide great flexibility to customize and extend deco’s functionality to meet your specific needs. With the ability to create custom Matchers, you can integrate external data sources, perform complex calculations, and implement intricate logic to determine user segmentation and deliver personalized experiences.

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Harnessing the Power of Matchers in Variants

Matchers form the backbone of Variants in deco. By combining Matchers with different conditions, you can create targeted content variations for specific user segments. Variants enable you to modify and personalize content dynamically based on the evaluation of Matchers. When configuring Variants, you can select the appropriate Matcher for each segment and define the conditions that determine whether a user belongs to that segment. By utilizing Matchers in Variants, you can fine-tune the user experience, optimize content delivery, and deliver personalized interactions.