This guide will help you navigate through changes included in version 3 of the Fastly CDN integration for a successful upgrade.

These changes aim to make the configuration of the module easier by centralizing all the settings and filters in the init.vcl snippet.

Overview of changes

Creation of datadome_settings and datadome_patterns tables to configure the module
Rename datadome_restore_referrer option to enable_referrer_restoration
Ignore matrix params from the path for the regex comparisons
Inspection of static-looking paths containing one of %23 %25 %2f %3b %3f

Migration steps

Step 1: Use latest snippets

Download the latest DataDome Fastly module package here.

In version 2.x.x, each setting had to be located and edited by line number across several snippets. Version 3.x.x centralizes every setting and regex into two tables, datadome_settings and datadome_patterns, declared in init.vcl. You therefore need to replace every snippets with the new ones, following the same procedure used for the initial integration:

If you use VCL snippets through the Fastly dashboard, clone your service to a new version and re-upload each of the 7 snippets (init, recv, miss, pass, fetch, error, deliver), replacing the previous content.
If you use regular VCL snippets with Terraform, replace the local .vcl files referenced by the dynamic "snippet" block with the new ones from the package.

Step 2: Migrate configurations

Open init.vcl and locate the datadome_settings and datadome_patterns table declarations. For each setting you previously customized, use the mapping below to find its new location and report the value.

`datadome_settings`

Previous location (v2.x.x)	New setting (v3.x.x)	Notes
License key (~line 48 of `init.vcl`)	`server_side_key`	Report the value of your server-side key into this entry.
`datadome_restore_referrer` (~line 125, `vcl_recv`)	`enable_referrer_restoration`	Renamed setting, same boolean behavior.
`datadome_enable_graphql_support` (~line 127, `vcl_recv`)	`enable_graphql_support`	Remove `datadome` prefix, now centralized in the table.
`datadome_enable_replay_protection` (~line 129, `vcl_recv`)	`enable_replay_protection`	Remove `datadome` prefix, now centralized in the table.
`datadome_enable_mcp_support` (~line 131, `vcl_recv`)	`enable_mcp_support`	Remove `datadome` prefix, now centralized in the table.
N/A (new behavior)	`remove_matrix_params` (default `true`)	New setting. Matrix params are now stripped from each path segment before it is evaluated against the `datadome_patterns` regexes. Set to `false` to keep the previous (unstripped) behavior.

`datadome_patterns`

Previous location (v2.x.x)	New setting (v3.x.x)	Notes
Regex (~line 381, single field used to include/exclude requests from inspection)	`static_asset_exclusion` and `url_pattern_exclusion`	The single regex has been split in two: keep the default static-asset allowlist in `static_asset_exclusion`, and move any custom pattern you had added into `url_pattern_exclusion`.
N/A (new setting)	`encoded_char_inclusion`	New setting. Encoded characters matching this regex force a request that matched the static-asset exclusion back into inspection.
N/A (previously hardcoded)	`graphql_endpoint` (default `(?i)graphql`)	New dedicated setting for the GraphQL endpoint match, previously hardcoded in the snippet logic.
N/A (previously hardcoded)	`mcp_endpoint` (default `(?i)mcp`)	New dedicated setting for the MCP endpoint match, previously hardcoded in the snippet logic.

Custom fields

The handleCustomFields subroutine (used to send userID, productID, and other custom fields) is renamed for handle_custom_fields.

Just the name of the function changed, keep your existing implementation as is.