Middleware edits

Author: rchinn1

src/connections/sources/catalog/libraries/website/javascript/middleware.md

@@ -4,34 +4,33 @@ strat: ajs
 ---
 
 
-Middlewares allow developers to extend Analytics.js with custom code which runs on every event. This code has full access to the DOM and Browser API, and helps customers enrich and transform event payloads. Source Middlewares and Destination Middlewares are available on the Analytics.js snippet version `4.12.0` and later.
+Middlewares allow developers to extend Analytics.js with custom code that runs on every event. This code has full access to the DOM and Browser API, and helps customers enrich and transform event payloads. Source and destination middlewares are available on the Analytics.js snippet version `4.12.0` and later.
 
-Analytics.js can be extended using two functions:
+Analytics.js can be extended using 2 functions:
 
 ```js
 addSourceMiddleware(middleware)
 addDestinationMiddleware(targetIntegration, middleware1, middleware2, ...)
 ```
 
-The first function (Source Middleware) allows you to manipulate the payload and filter events on a per-source basis, while the second function (Destination Middleware) allows this on a per destination basis. Middlewares run in the browser.
+The first function (source middleware) allows you to manipulate the payload and filter events on a per-source basis, while the second function (destination middleware) allows this on a per destination basis. Middlewares run in the browser.
 
 > info ""
-> **Note**: Destination-middleware only act on [data sent to destinations in device-mode](/docs/connections/destinations#connection-modes). Since the destination middleware code exists in your app or project, it cannot transform the data sent from the Segment servers to the destination endpoint.
+> Destination-middleware only act on [data sent to destinations in device-mode](/docs/connections/destinations#connection-modes). Since the destination middleware code exists in your app or project, it cannot transform the data sent from the Segment servers to the destination endpoint.
 
-## Using Source Middlewares
+## Using source middlewares
 
 To add source middleware, use the following API:
 
 ```js
 analytics.addSourceMiddleware(({ payload, next, integrations }) => .... )
 ```
 
-- `payload` represents the event payload sent by Analytics.js. To change the value of the `payload`, mutate the `payload.obj` object. (See the example below.)
+- `payload` represents the event payload sent by Analytics.js. To change the value of the `payload`, mutate the `payload.obj` object, as in the example below. 
 - `next` represents the next function to be called in the source middleware chain. If the middleware provided does not call this function, the event is dropped on the client and is not delivered to Segment or any destinations.
-- `integrations` is an array of objects representing all the integrations that the payload is sent to. If an integration in this array is set to a ‘falsey' value then the event is not be sent to the Integration.
+- `integrations` is an array of objects representing all the integrations that the payload is sent to. If an integration in this array is set to a falsy value, then the event is not sent to the integration.
 
-### Examples
-#### Modifying an event
+#### Example: Modifying an event
 ```js
 analytics.addSourceMiddleware(({ payload, next }) => {
     const { event } = payload.obj.context
@@ -42,7 +41,7 @@ analytics.addSourceMiddleware(({ payload, next }) => {
 });
 ```
 
-#### Dropping an event
+#### Example: Dropping an event
 ```js
 analytics.addSourceMiddleware(({ payload, next }) => {
   const { event } = payload.obj.context
@@ -53,7 +52,7 @@ analytics.addSourceMiddleware(({ payload, next }) => {
 });
 ```
 
-## Using Destination Middlewares
+## Using destination middlewares
 
 
 To add destination middleware, use the following API:
@@ -62,7 +61,7 @@ To add destination middleware, use the following API:
 analytics.addDestinationMiddleware('integrationA', ({ payload, next, integration }) => .... )
 ```
 
-- `payload` represents the event payload sent by Analytics.js. To change the value of the `payload`, mutate the `payload.obj` object. (See the example below.)
+- `payload` represents the event payload sent by Analytics.js. To change the value of the `payload`, mutate the `payload.obj` object, as in the example below.
 - `next` represents the next function to be called in the destination middleware chain. If the middleware provided does not call this function, then the event is dropped completely for the given destination.
 - `integration` is a string value representing the integration that this middleware is applied to. To apply middleware to all destinations (excluding Segment.io), you can use the `*` value.
 
@@ -87,29 +86,29 @@ analytics.addDestinationMiddleware('integrationA', ({ payload, next, integration
 
 
 > info ""
-> **Note**: Destination-middleware only act on [data sent to destinations in device-mode](/docs/connections/destinations#connection-modes). Since the destination middleware code exists in your app or project, it cannot transform the data sent from the Segment servers to the destination endpoint.
+> Destination middleware only act on [data sent to destinations in device-mode](/docs/connections/destinations#connection-modes). Since the destination middleware code exists in your app or project, it cannot transform the data sent from the Segment servers to the destination endpoint.
 
 ## Adding middlewares to Analytics.js
 
-The above defined Source & Destination Middleware can be added to the Analytics.js execution chain as:
+The above defined source and destination middleware can be added to the Analytics.js execution chain as:
 
 ```js
 analytics.addSourceMiddleware(() => ...);
 analytics.addDestinationMiddleware('integrationA', () => ...);
 ```
 
 
-You can call the `.addSourceMiddleware(fn)` multiple times, and the order of operations reflects the order in which you register your Source Middleware.
+You can call the `.addSourceMiddleware(fn)` multiple times, and the order of operations reflects the order in which you register your source middleware.
 
 Both `.addSourceMiddleware(fn)` and `.addDestinationMiddleware('integration', fn, ...)` can be called before [`.load()`](/docs/connections/sources/catalog/libraries/website/javascript/#load-options).
 
-## Braze Middleware
+## Braze middleware
 
-If you use the Braze (Appboy) destination in either [cloud or device mode](/docs/connections/destinations/#connection-modes) you can save Braze costs by "debouncing" duplicate `identify()` calls from Segment by adding our [open-source Middleware tool](https://github.com/segmentio/segment-braze-mobile-middleware) to your implementation.
+If you use the Braze (Appboy) destination in either [cloud or device mode](/docs/connections/destinations/#connection-modes) you can reduce Braze costs by debouncing duplicate Identify calls from Segment. You can achieve this by adding Segment's [open-source middleware tool](https://github.com/segmentio/segment-braze-mobile-middleware){:target="_blank"} to your implementation.
 This optional middleware is disabled by default. When enabled, it ensures that only events where at least one changed trait value are sent to Braze, and events with duplicate traits are not sent.
 
-To enable this Middleware for a JavaScript or Project source, go to `Analytics.js` in your source settings.
+To enable this middleware for a JavaScript or Project source, go to **Analytics.js** in your source settings.
 
 ![BrazeMiddleware](images/sources_ajs_brazemiddleware.png)
 
-More information about this tool and how it works [is available in the project's README](https://github.com/segmentio/segment-braze-mobile-middleware/blob/master/README.md#how-does-this-work).
+More information about this tool and how it works is available in the project's [README](https://github.com/segmentio/segment-braze-mobile-middleware/blob/master/README.md#how-does-this-work){:target="_blank"}.