pyrate_limiter.buckets.sqlite_bucket module

Bucket implementation using SQLite

class pyrate_limiter.buckets.sqlite_bucket.Queries

Bases: object

COUNT_ALL = "SELECT COUNT(*) FROM '{table}'"

COUNT_BEFORE_INSERT = "\n    SELECT :interval{index} as interval, COUNT(*) FROM '{table}'\n    WHERE item_timestamp >= :current_timestamp - :interval{index}\n    "

COUNT_BEFORE_LEAK = "SELECT COUNT(*) FROM '{table}' WHERE item_timestamp < {current_timestamp} - {interval}"

CREATE_BUCKET_TABLE = "\n    CREATE TABLE IF NOT EXISTS '{table}' (\n        name VARCHAR,\n        item_timestamp INTEGER\n    )\n    "

CREATE_INDEX_ON_TIMESTAMP = "\n    CREATE INDEX IF NOT EXISTS '{index_name}' ON '{table_name}' (item_timestamp)\n    "

DROP_INDEX = "DROP INDEX IF EXISTS '{index}'"

DROP_TABLE = "DROP TABLE IF EXISTS '{table}'"

FLUSH = "DELETE FROM '{table}'"

GET_ALL_ITEM = "SELECT * FROM '{table}' ORDER BY item_timestamp ASC"

GET_FIRST_ITEM = "SELECT name, item_timestamp FROM '{table}' ORDER BY item_timestamp ASC"

GET_LAG = "\n    SELECT (strftime ('%s', 'now') || substr(strftime ('%f', 'now'), 4)) - (\n    SELECT item_timestamp\n    FROM '{table}'\n    ORDER BY item_timestamp\n    ASC\n    LIMIT 1\n    )\n    "

LEAK = 'DELETE FROM "{table}" WHERE rowid IN (\n    SELECT rowid FROM "{table}" ORDER BY item_timestamp ASC LIMIT {count});'

PEEK = 'SELECT * FROM "{table}" ORDER BY item_timestamp DESC LIMIT 1 OFFSET {count}'

PUT_ITEM = "\n    INSERT INTO '{table}' (name, item_timestamp) VALUES %s\n    "

class pyrate_limiter.buckets.sqlite_bucket.SQLiteBucket(rates, conn, table)

Bases: pyrate_limiter.abstracts.bucket.AbstractBucket

For sqlite bucket, we are using the sql time function as the clock item’s timestamp wont matter here

conn

count()

Count number of items in the bucket

Return type

int

flush()

Flush the whole bucket - Must remove failing-rate after flushing

Return type

None

full_count_query

classmethod init_from_file(rates, table, create_new_table=True)

Return type

SQLiteBucket

leak(current_timestamp=None)

Leaking/clean up bucket

Return type

int

lock

peek(index)

Peek at the rate-item at a specific index in latest-to-earliest order NOTE: The reason we cannot peek from the start of the queue(earliest-to-latest) is we can’t really tell how many outdated items are still in the queue

Return type

Optional[RateItem]

put(item)

Put an item (typically the current time) in the bucket return true if successful, otherwise false

Return type

bool

rates

table