Code examples using expressly

These code examples have an implementation in JavaScript using expressly. To learn more about using JavaScript with expressly and our Compute platform, see using JavaScript and expressly's documentation.

NOTE: Some of the code examples here are also available in other languages. To help with migrations or learning, where a code example has multiple implementations, we show all implementations together.

Response manipulation

Add a new field to a JSON response

Decorate API responses in JSON format with new fields.

Backends Performance

Use microservices to divide up a domain

Send request to different origin servers based on the URL path.

Request manipulation Edge data Security

Create self-destructing URLs for time-limited access

Make URLs expire after a configurable period.

Request manipulation Cache Performance

Filter query string parameters

Add, remove, and sort querystring parameters.

Request manipulation

Change request method

Change PUT, DELETE, OPTIONS and others to POST, or vice versa, to help integrate incompatible client and server apps.

Request manipulation Response manipulation Performance

Add or remove cookies

Read individual cookies, set new cookies in response.

Request manipulation Response manipulation Security

Filter cookies or other structured headers

Rewrite headers to keep only keys that you want to allow, similar to `querystring.filter_except` but for headers rather than querystrings.

Logging Observability

Log request data to Google BigQuery

Build raw JSON strings matching your BigQuery table schema to send log data to BigQuery.

Compute intersection of two lists

Useful for comparing capabilities with required permissions.

Response manipulation Edge data SEO

Set Google Analytics _ga cookie

Due to ITP 2.1 restrictions, cookies set in JavaScript may be limited to a 7-day TTL. Set your Google Analytics cookie on the edge to avoid this.

Response manipulation Edge data Performance

Redirect old URLs at the edge

Use a dictionary of URL mappings to serve your redirects at lightning speed.

Request manipulation Personalization

Add time zone offset to requests

Divide the world into time bands of custom size and forward time zone data to your origin server.

Developer experience

Format time expressions

Format dates and times in a variety of ways.

Response manipulation Edge data Developer experience

Perform redirects with wildcard patterns using an edge dictionary

Match URL prefixes and make use of configurable response status and querystring preservation.

Validate domain on query string

Check the query string if it contains a valid domain.

All code on this page is provided under both the BSD and MIT open source licenses.

User contributed notes

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