us.whitford.fulcro.rad.database-adapters.datalevin.pathom-plugin — us.whitford/fulcro-rad-datalevin 1.0.0-RC1

Pathom environment wiring for the Datalevin database adapter.

This namespace has NO hard dependency on any Pathom version:

• wrap-env is a plain (fn [env] env') augmentor. It is the idiomatic Pathom 3 integration point — compose it into the env-middleware you pass to RAD's com.fulcrologic.rad.pathom3/new-processor (alongside attr/wrap-env and form/wrap-env).
• pathom-plugin wraps that same augmentation in a Pathom 2 ::p/wrap-parser plugin map (a plain namespaced keyword literal — no pathom require needed), for use with com.fulcrologic.rad.pathom/new-parser.

pathom-plugin clj

(pathom-plugin database-mapper)

Create a Pathom 2 plugin that adds Datalevin database support.

The plugin augments the parsing env for each request so that the current database value is available to all resolvers. Database snapshots are taken once per request (parser call) and reused for consistency.

Arguments:

• database-mapper: a function (fn [pathom-env] {schema-name connection}) for a given request.

The resulting pathom-env available to all resolvers will then have:

• dlo/connections: the result of database-mapper
• dlo/databases: a map from schema name to current database values

Returns a Pathom 2 plugin map keyed by :com.wsscode.pathom.core/wrap-parser (the keyword is written as a literal, so this namespace does not depend on pathom being present).

For Pathom 3, do not use this plugin; compose wrap-env into your processor's env-middleware instead.

refresh-db-snapshot! clj

(refresh-db-snapshot! env schema db-after)

Publish db-after into the atom-backed dlo/databases snapshot for schema in env, so resolvers running later in the same Pathom request read their own writes while keeping a stable, request-scoped view.

Called by the save/delete middleware with the transaction report's :db-after. No-op when db-after is nil or when env has no atom snapshot for schema (e.g. a save-only env with no read wiring). Returns nil.

wrap-env clj

(wrap-env database-mapper)

(wrap-env base-wrapper database-mapper)

Wrap the pathom environment with database connections and snapshots.

This is the Pathom 3 integration point: the returned (fn [env] env') can be composed into the env-middleware given to RAD's Pathom 3 processor.

Arguments:

• base-wrapper: optional function to further wrap the env
• database-mapper: function that takes env and returns map of schema -> connection

Returns a function that wraps the environment, adding:

• dlo/connections: the result of database-mapper (schema -> connection)
• dlo/databases: a map from schema name to an atom holding the current Datalevin database value. Storing an atom (rather than a bare db) lets the save/delete middleware publish the post-transaction :db-after into the same request env, so resolvers running later in the request read their own writes. See refresh-db-snapshot!.