Redis Quest
This is a redis module (using RedisGears) that provides AWS SQS like api on top of redis.
Supported features
- Visibility timeout
- inFlight visibility
- Dead letter queues
- Message handle
Installing
There are a set of commands in the Makefile which will help you run and install this library locally. To be able to run this on your redis server you need to make sure the RedisGears module is loaded on that redis server.
start (Requires Docker)
make start runs a RedisGears enabled redis server via docker
load
Will load all of the libraries commands into your local redis server. You could modify this command to target your remote redis server. After loading this module on a redis server you will be able to run the commands on that server.
unload (WARNING ⚠️ )
Will unregister commands from a redis server. This was useful while testing but should not be used in a server where other RedisGears commands are loaded as this will delete them indescriminately.
Api
This module adds 3 different RedisGears commands.
sendMessage
Sends a message to a queue with an optional visibility timeout.
RG.TRIGGER sendMessage list_name value [timeout]list_name (required)
The name of the list to add this message to
value (required)
The message itself
timeout (optional)
Amount of seconds before this message is visible
getMessage
Get a message from a list and optionally set its visibility timeout.
RG.TRIGGER getMessage list_name count [timeout]list_name (required)
The name of the list to get messages from
count (required)
The amount of messages to get from the list
timeout (optional)
Amount of seconds you need to process this message, after the timeout. Quest will make this message visible again for anyone else to process and the handle will not be able to remove this message from the list
Returns
The list of items specified by count or an empty array if list doesn't exist or has no more items. If the list has less items available(not in-flight) than those specified by count it will only return those.
each item is represented by an array of values that map to a dictionary:
"['uuid', <uuid>, 'value', <msg_value>, 'tries', <number>, 'in_flight', <python_bool[True|False]>, 'list', <string>, 'handle', <uuid>]"
Message fields
uuid
The immutable id given to the message when sent to Quest. This uuid will never change inside Quest even when the message gets moved to a DLQ
value
whatever value was assigned to the message when added to Quest
tries
The amount of times the message has been delivered before without it being deleted/processed. In the apps current state, after reaching 5 it will be sent to a DLQ
in_flight
For internal use only. Flag to know if the message is currently in flight or not
list
The name of the list this message was retrieved from
handle
The used to delete this message
deleteMessage
Delete a message from a queue
RG.TRIGGER deleteMessage list_name handlelist_name (required)
The list to remove this message from
handle (required)
The handle given to this message via getMessage. Notice that a single message gets different handles every time it delivered via getMessage
If a message tries to get deleted after its timeout has expired a Message not in flight message will be returned