Sqkon/com.mercury.sqkon.db/KeyValueStorage

KeyValueStorage

open class KeyValueStorage<T : Any>(entityName: String, entityQueries: EntityQueries, metadataQueries: MetadataQueries, scope: CoroutineScope, type: KType, serializer: SqkonSerializer = KotlinSqkonSerializer(), config: KeyValueStorage.Config = Config(), readDispatcher: CoroutineDispatcher, writeDispatcher: CoroutineDispatcher, transacter: SqkonTransacter)(source)

Base interaction to the database.

Parameters

serializer

if providing your own, recommend using SqkonJson to make sure you create fields consistently.

Constructors

KeyValueStorage

constructor(entityName: String, entityQueries: EntityQueries, metadataQueries: MetadataQueries, scope: CoroutineScope, type: KType, serializer: SqkonSerializer = KotlinSqkonSerializer(), config: KeyValueStorage.Config = Config(), readDispatcher: CoroutineDispatcher, writeDispatcher: CoroutineDispatcher, transacter: SqkonTransacter)

Types

Config

data class Config(val deserializePolicy: KeyValueStorage.Config.DeserializePolicy = DeserializePolicy.ERROR, val dispatcher: CoroutineDispatcher = Dispatchers.Default)

Functions

count

fun count(where: Where<T>? = null, expiresAfter: Instant? = null): Flow<Int>

delete

fun delete(where: Where<T>? = null)

Delete using where clause. If where is null, all rows will be deleted.

deleteAll

fun deleteAll()

Delete all rows. Basically an alias for delete with no where set.

deleteByKey

fun deleteByKey(key: String)

Delete by key.

deleteByKeys

fun deleteByKeys(vararg key: String)

Delete by keys.

deleteExpired

fun deleteExpired(expiresAfter: Instant = Clock.System.now())

Purge all rows that have there expired_at field NOT null and less than (<) the date passed in. (Usually Clock.System.now).

deleteStale

fun deleteStale(writeInstant: Instant? = Clock.System.now(), readInstant: Instant? = Clock.System.now())

Unlike deleteExpired, this will clean up rows that have not been touched (read/written) before the passed in time.

deleteState

fun ~~deleteState~~(instant: Instant)

Unlike deleteExpired, this will clean up rows that have not been touched (read/written) before the passed in time.

insert

fun insert(key: String, value: T, ignoreIfExists: Boolean = false, expiresAt: Instant? = null)

Insert a row.

insertAll

fun insertAll(values: Map<String, T>, ignoreIfExists: Boolean = false, expiresAt: Instant? = null)

Insert multiple rows.

metadata

fun metadata(): Flow<Metadata>

Metadata for the entity, this will tell you the last time the entity store was read and written to, useful for cache invalidation.

select

fun select(where: Where<T>? = null, orderBy: List<OrderBy<T>> = emptyList(), limit: Long? = null, offset: Long? = null, expiresAfter: Instant? = null): Flow<List<T>>

Select using where clause. If where is null, all rows will be selected.

selectAll

fun selectAll(orderBy: List<OrderBy<T>> = emptyList(), expiresAfter: Instant? = null): Flow<List<T>>

Select all rows. Effectively an alias for select with no where set.

selectByKey

fun selectByKey(key: String): Flow<T?>

Select by key.

selectByKeys

fun selectByKeys(keys: Collection<String>, orderBy: List<OrderBy<T>> = emptyList(), expiresAfter: Instant? = null): Flow<List<T>>

Select by keys with optional ordering

selectKeysetPagingSource

fun selectKeysetPagingSource(pageSize: Int, where: Where<T>? = null, orderBy: List<OrderBy<T>> = emptyList(), expiresAfter: Instant? = null): PagingSource<String, T>

Create a PagingSource that pages through results using keyset-based pagination. Unlike selectPagingSource, this avoids the O(n) cost of SQL OFFSET on large datasets by using pre-calculated page boundary keys.

selectPagingSource

fun selectPagingSource(where: Where<T>? = null, orderBy: List<OrderBy<T>> = emptyList(), initialOffset: Int = 0, expiresAfter: Instant? = null): PagingSource<Int, T>

Create a PagingSource that pages through results according to queries generated from the passed in where and orderBy. initialOffset initial offset to start paging from.

selectResult

fun selectResult(where: Where<T>? = null, orderBy: List<OrderBy<T>> = emptyList(), limit: Long? = null, offset: Long? = null, expiresAfter: Instant? = null): Flow<List<ResultRow<T>>>

Select using where clause. If where is null, all rows will be selected.

transaction

fun <T : Any> KeyValueStorage<T>.transaction(body: SqkonTransactionScope.() -> Unit)

Run body in a database transaction. Calling SqkonTransactionScope.rollback discards the work and returns silently.

transactionWithResult

fun <T : Any, R> KeyValueStorage<T>.transactionWithResult(body: SqkonTransactionScope.() -> R): R

Run body in a database transaction and return its value. Calling SqkonTransactionScope.rollback aborts the transaction and throws SqkonRollbackException (there is no value to return).

update

fun update(key: String, value: T, expiresAt: Instant? = null)

Update a row. If the row does not exist, it will update nothing, use insert if you want to insert if the row does not exist.

updateAll

fun updateAll(values: Map<String, T>, expiresAt: Instant? = null)

Convenience function to insert collection of rows. If the row does not exist, it will update nothing, use insert if you want to insert if the row does not exist.

upsert

fun upsert(key: String, value: T, expiresAt: Instant? = null)

Convenience function to insert a new row or update an existing row.

upsertAll

fun upsertAll(values: Map<String, T>, expiresAt: Instant? = null)

Convenience function to insert new or update existing multiple rows.