toucan2.query — io.github.camsaul/toucan2 1.0.505

apply-kv-arg clj

(apply-kv-arg model₁ resolved-query₂ k₃ v)

Merge a key-value pair into a query, presumably a map. What this means depends on the [[toucan2.protocols/dispatch-value]] of query -- for a plain map, this is given :type metadata at some point for the toucan2.map-backend/default-backend.

Example: the default Honey SQL backend, applies k and v as a :where condition:

(apply-kv-arg :default {} :k :v)
;; =>
{:where [:= :k :v]}

You can add new implementations of this method to special behaviors for support arbitrary keys, or to support new query backends. :toucan/pk support is implemented this way.

apply-kv-arg is defined in toucan2.query (toucan2/query.clj:125).

It caches methods using a methodical.impl.cache.watching.WatchingCache.

It uses the method combination methodical.impl.combo.threaded.ThreadingMethodCombination with the threading strategy :thread-last.

It uses the dispatcher methodical.impl.dispatcher.multi_default.MultiDefaultDispatcher with hierarchy #'clojure.core/global-hierarchy and prefs {}.

The default value is :default.

It uses the method table methodical.impl.method_table.standard.StandardMethodTable.

These primary methods are known:

• [:default clojure.lang.IPersistentMap :default], defined in toucan2.query (toucan2/query.clj:151)

  It has the following documentation:

  Default implementation for maps. This adds :type metadata to the map (from [[map/backend]]) and recurses, ultimately handing off to the map backend's implementation.

  See toucan2.map-backend.honeysql2 for the Honey SQL-specific impl for this.

• [:default :toucan.map-backend/honeysql2 :default], defined in toucan2.map-backend.honeysql2 (toucan2/map_backend/honeysql2.clj:33)

  It has the following documentation:

  Apply key-value args to a Honey SQL 2 query map.

These aux methods are known:

:around methods:

• [:default :default :toucan/pk], defined in toucan2.query (toucan2/query.clj:216)

  It has the following documentation:

  Implementation for handling key-value args for :toucan/pk.

  This is an :around so we can intercept the normal handler. This 'unpacks' the PK and ultimately uses the normal calls to apply-kv-arg.

apply-kv-args clj

(apply-kv-args model query kv-args)

Convenience. Merge a map of kv-args into a resolved query with repeated calls to apply-kv-arg.

parse-args clj

(parse-args query-type₁ unparsed-args)

parse-args takes a sequence of unparsed args passed to something like toucan2.select/select and parses them into a parsed args map. The default implementation uses [[clojure.spec.alpha]] to parse the args according to args-spec.

These keys are commonly returned by several of the different implementations parse-args, and other tooling is build to leverage them:

• :modelable -- usually the first of the unparsed-args, this is the thing that should get resolved to a model with toucan2.model/resolve-model.

• :queryable -- something that can be resolved to a query, for example a map or integer or 'named query' keyword. The resolved query is ultimately combined with other parsed args and built into something like a Honey SQL map, then compiled to something like SQL.

• :kv-args -- map of key-value pairs. When [[build]] builds a query, it calls apply-kv-arg for each of the key-value pairs. The default behavior is to append a Honey SQL :where clause based on the pair; but you can customize the behavior for specific keywords to do other things -- :toucan/pk is one such example.

• :columns -- for things that return instances, :columns is a sequence of columns to return. These are commonly specified by wrapping the modelable in a [modelable & columns] vector.

parse-args is defined in toucan2.query (toucan2/query.clj:92).

It caches methods using a methodical.impl.cache.watching.WatchingCache.

It uses the method combination methodical.impl.combo.threaded.ThreadingMethodCombination with the threading strategy :thread-last.

It uses the dispatcher methodical.impl.dispatcher.multi_default.MultiDefaultDispatcher with hierarchy #'clojure.core/global-hierarchy and prefs {}.

The default value is :default.

It uses the method table methodical.impl.method_table.standard.StandardMethodTable.

These primary methods are known:

• :default, defined in toucan2.query (toucan2/query.clj:117)

  It has the following documentation:

  The default implementation calls parse-args-with-spec with the :toucan2.query/default-args spec.

• :toucan.query-type/insert.*, defined in toucan2.insert (toucan2/insert.clj:32)

  It has the following documentation:

  Default args parsing method for toucan2.insert/insert!. Uses the spec :toucan2.insert/args.

parse-args-with-spec clj

(parse-args-with-spec query-type spec unparsed-args)

Parse unparsed-args for query-type with the given spec. See documentation for parse-args for more details.