Local

Local lookup lists hold key-only membership sets and key-value pairs entirely in memory. They are well suited to small, slow-changing sets of static data, consulted from expressions or Sieve filters.

Key-only lists

Key-only lists, useful for membership tests such as allow-lists and deny-lists, are defined through the MemoryLookupKey object (found in the WebUI under Settings › Lookups › In-Memory Keys, Settings › Spam Filter › Lists › Blocked Domains, Settings › Spam Filter › Lists › Spam Traps, Settings › Spam Filter › Lists › Trusted Domains, Settings › Spam Filter › Lists › URL Redirectors). Each record has:

• namespace: the lookup namespace the key belongs to (required). All records sharing a namespace form a single lookup list.
• key: the key name (required, up to 255 characters).
• isGlobPattern: when true, the key is interpreted as a glob pattern, matching multiple concrete keys (for example *.example.com or mx?.example.org). Default: false.

To build a list of allowed domains, for instance, create one MemoryLookupKey record per entry, all sharing the namespace allow-list-domain, with the domain as the key.

Key-value lists

Lists that associate a value with each key are defined through the MemoryLookupKeyValue object (found in the WebUI under Settings › Lookups › In-Memory Key-Values). Each record has the same namespace, key, and isGlobPattern fields as MemoryLookupKey, plus:

• value: the value associated with the key (required).