Skip to content
Merged
Show file tree
Hide file tree
Changes from all commits
Commits
File filter

Filter by extension

Filter by extension

Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
100 changes: 100 additions & 0 deletions content/develop/clients/go/transpipe.md
Original file line number Diff line number Diff line change
@@ -0,0 +1,100 @@
---
categories:
- docs
- develop
- stack
- oss
- rs
- rc
- oss
- kubernetes
- clients
description: Learn how to use Redis pipelines and transactions
linkTitle: Pipelines/transactions
title: Pipelines and transactions
weight: 2
---

Redis lets you send a sequence of commands to the server together in a batch.
There are two types of batch that you can use:

- **Pipelines** avoid network and processing overhead by sending several commands
to the server together in a single communication. The server then sends back
a single communication with all the responses. See the
[Pipelining]({{< relref "/develop/use/pipelining" >}}) page for more
information.
- **Transactions** guarantee that all the included commands will execute
to completion without being interrupted by commands from other clients.
See the [Transactions]({{< relref "/develop/interact/transactions" >}})
page for more information.

## Execute a pipeline

To execute commands in a pipeline, you first create a pipeline object
and then add commands to it using methods that resemble the standard
command methods (for example, `Set()` and `Get()`). The commands are
buffered in the pipeline and only execute when you call the `Exec()`
method on the pipeline object.

The main difference with the pipeline commands is that their return
values contain a valid result only after the pipeline has finished executing.
You can access the result using the `Val()` method instead of
`Result()` (note that errors are reported by the `Exec()` method rather
than by the individual commands).

{{< clients-example pipe_trans_tutorial basic_pipe Go >}}
{{< /clients-example >}}

You can also create a pipeline using the `Pipelined()` method.
This executes pipeline commands in a callback function that you
provide and calls `Exec()` automatically after it returns:

{{< clients-example pipe_trans_tutorial basic_pipe_pipelined Go >}}
{{< /clients-example >}}

## Execute a transaction

A transaction works in a similar way to a pipeline. Create a
transaction object with the `TxPipeline()` method, call command methods
on that object, and then call the transaction object's
`Exec()` method to execute it. You can access the results
from commands in the transaction after it completes using the
`Val()` method.

{{< clients-example pipe_trans_tutorial basic_trans Go >}}
{{< /clients-example >}}

There is also a `TxPipelined()` method that works in a similar way
to `Pipelined()`, described above:

{{< clients-example pipe_trans_tutorial basic_trans_txpipelined Go >}}
{{< /clients-example >}}

## Watch keys for changes

Redis supports *optimistic locking* to avoid inconsistent updates
to different keys. The basic idea is to watch for changes to any
keys that you use in a transaction while you are are processing the
updates. If the watched keys do change, you must restart the updates
with the latest data from the keys. See
[Transactions]({{< relref "/develop/interact/transactions" >}})
for more information about optimistic locking.

The code below reads a string
that represents a `PATH` variable for a command shell, then appends a new
command path to the string before attempting to write it back. If the watched
key is modified by another client before writing, the transaction aborts.
The `Watch()` method receives a callback function where you execute the
commands you want to watch. In the body of this callback, you can execute
read-only commands before the transaction using the usual client object
(called `rdb` in our examples) and receive an immediate result. Start the
transaction itself by calling `TxPipeline()` or `TxPipelined()` on the
`Tx` object passed to the callback. `Watch()` also receives one or more
`string` parameters after the callback that represent the keys you want
to watch.

For production usage, you would generally call code like the following in
a loop to retry it until it succeeds or else report or log the failure:

{{< clients-example pipe_trans_tutorial trans_watch Go >}}
{{< /clients-example >}}
2 changes: 1 addition & 1 deletion content/develop/clients/jedis/transpipe.md
Original file line number Diff line number Diff line change
Expand Up @@ -48,7 +48,7 @@ result using the `Response` object's `get()` method.
## Execute a transaction

A transaction works in a similar way to a pipeline. Create a
transaction object with the `multi()`, call command methods
transaction object with the `multi()` command, call command methods
on that object, and then call the transaction object's
`exec()` method to execute it. You can access the results
from commands in the transaction using `Response` objects, as
Expand Down
Loading