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Code blocks

Code is used 23 times on 11 pages.

Pages which use Code

Used 23 times.

Pages

Partials

Code blocks are powered by Expressive Code ↗, a project by Astro. This is just a small showcase of the wide functionality of this component.

Learn more about formatting in the code block formatting guide.

PowerShell
Write-Output "This one has a title!"
JavaScript
// Collapsing
const foo = {
3 collapsed lines
  1: 1,
  2: 2,
  3: 3,
};
JavaScript
// Line numbers
const foo = "bar";
const bar = "baz";
JavaScript
// Example with wrap
function getLongString() {
  return "This is a very long string that will most probably not fit into the available space unless the container is extremely wide";
}
JavaScript
function demo() {
  console.log("These are inserted and deleted marker types");
  // The return statement uses the default marker type
  return true;
}
JavaScript
function thisIsJavaScript() {
  // This entire block gets highlighted as JavaScript,
  // and we can still add diff markers to it!
  console.log('Old code to be removed')
  console.log('New and shiny code!')
}
 
```powershell title="PowerShell"
Write-Output "This one has a title!"
```


```js collapse={3-5}
// Collapsing
const foo = {
  1: 1,
  2: 2,
  3: 3,
};
```


```js showLineNumbers
// Line numbers
const foo = "bar";
const bar = "baz";
```


```js wrap
// Example with wrap
function getLongString() {
  return "This is a very long string that will most probably not fit into the available space unless the container is extremely wide";
}
```


```js "return true;" ins="inserted" del="deleted"
function demo() {
  console.log("These are inserted and deleted marker types");
  // The return statement uses the default marker type
  return true;
}
```


```diff lang="js"
  function thisIsJavaScript() {
    // This entire block gets highlighted as JavaScript,
    // and we can still add diff markers to it!
-   console.log('Old code to be removed')
+   console.log('New and shiny code!')
  }
```

Output

If you would like to include the output of your code block, create a second code block below and add the output property to the opening code fence.

Terminal window
npx wrangler vectorize create tutorial-index --dimensions=3 --metric=cosine
✅ Successfully created index 'tutorial-index'


[[vectorize]]
binding = "VECTORIZE_INDEX" # available in your Worker on env.VECTORIZE_INDEX
index_name = "tutorial-index"
```sh
npx wrangler vectorize create tutorial-index --dimensions=3 --metric=cosine
```


```sh output
✅ Successfully created index 'tutorial-index'


[[vectorize]]
binding = "VECTORIZE_INDEX" # available in your Worker on env.VECTORIZE_INDEX
index_name = "tutorial-index"
```

Workers Playground

If you add the playground option to the opening code fence for a Worker example, it will add a "Run Worker in Playground" link that will take the user to the Worker's playground

Live demo

JavaScript
export default {
  fetch() {
    return new Response("Test!");
  },
};
Run Worker in Playground

How to use

```js playground
export default {
  fetch() {
    return new Response("Test!");
  },
};
```
Run Worker in Playground

GraphQL API Explorer

Add graphql-api-explorer to the opening code fence to create a graphql code block with a Run in GraphQL API Explorer button that leads to GraphQL API Explorer ↗.

A GraphQL query
query ASingleDatasetExample($zoneTag: string, $start: Time, $end: Time) {
  viewer {
    zones(filter: { zoneTag: $zoneTag }) {
      firewallEventsAdaptive(
        filter: { datetime_gt: $start, datetime_lt: $end }
        limit: 2
        orderBy: [datetime_DESC]
      ) {
        action
        datetime
        host: clientRequestHTTPHost
      }
    }
  }
}
Run in GraphQL API Explorer
 
```graphql graphql-api-explorer title="A GraphQL query"
query ASingleDatasetExample($zoneTag: string, $start: Time, $end: Time) {
  viewer {
    zones(filter: { zoneTag: $zoneTag }) {
      firewallEventsAdaptive(
        filter: { datetime_gt: $start, datetime_lt: $end }
        limit: 2
        orderBy: [datetime_DESC]
      ) {
        action
        datetime
        host: clientRequestHTTPHost
      }
    }
  }
}
```

Variables

In the GraphQL API Explorer, the Variables section is automatically filled based on the names and types of the variables defined in your query:

  • Variables that include start and are of type Time are set to six hours before the current time
  • Variables that include end and are of type Time are set to the current time
  • Variables that include start and are of type Date are set to 24 hours before the current date
  • Variables that include end and are of type Date are set to the current date
  • Variables that include zoneTag and are of type string are set to "ZONE_ID"
  • Variables that include accountTag and are of type string are set to "ACCOUNT_ID"
  • Variables that include id and are of type string are set to "REPLACE_WITH_ID"
  • Variables that include limit and are of type int are set to 100
  • Any other variable with a type of string is set to "REPLACE_WITH_STRING"

You can also add custom variables by setting their values as a JSON string in the graphql-api-explorer metadata. The custom variables will be merged with the automatically populated variables.

In the following example, the custom value is custom-variable:

```graphql graphql-api-explorer='{"uID": "custom-variable"}' title="A GraphQL query"
query GraphqlExample($zoneTag: string, $start: Time, $end: Time) {
 viewer {
   zones(filter: { zoneTag: $zoneTag }) {
     ...
   }
 }
}
```

So, the Variables would look something like this:

{"zoneTag":"ZONE_ID", "start":"2025-09-11T14:00:00Z", "end":"2025-09-11T20:00:00Z", "uId": "custom-variable"}