-
Notifications
You must be signed in to change notification settings - Fork 0
Commit
This commit does not belong to any branch on this repository, and may belong to a fork outside of the repository.
- Loading branch information
0 parents
commit 3652d32
Showing
18 changed files
with
1,848 additions
and
0 deletions.
There are no files selected for viewing
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
Original file line number | Diff line number | Diff line change |
---|---|---|
@@ -0,0 +1,4 @@ | ||
# Used by "mix format" | ||
[ | ||
inputs: ["{mix,.formatter}.exs", "{config,lib,test}/**/*.{ex,exs}"] | ||
] |
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
Original file line number | Diff line number | Diff line change |
---|---|---|
@@ -0,0 +1,30 @@ | ||
name: CI | ||
|
||
on: [push, pull_request] | ||
|
||
jobs: | ||
build: | ||
|
||
name: Build and test | ||
runs-on: ubuntu-latest | ||
|
||
env: | ||
MIX_ENV: test | ||
GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }} | ||
steps: | ||
- uses: actions/checkout@v2 | ||
- name: Set up Elixir | ||
uses: erlef/setup-beam@988e02bfe678367a02564f65ca2e37726dc0268f | ||
with: | ||
elixir-version: '1.12.3' # Define the elixir version [required] | ||
otp-version: '24.1' # Define the OTP version [required] | ||
- name: Restore dependencies cache | ||
uses: actions/cache@v2 | ||
with: | ||
path: deps | ||
key: ${{ runner.os }}-mix-${{ hashFiles('**/mix.lock') }} | ||
restore-keys: ${{ runner.os }}-mix- | ||
- name: Install dependencies | ||
run: mix deps.get | ||
- name: Run tests | ||
run: mix coveralls.github |
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
Original file line number | Diff line number | Diff line change |
---|---|---|
@@ -0,0 +1,34 @@ | ||
name: Release | ||
|
||
on: workflow_dispatch | ||
|
||
jobs: | ||
build: | ||
|
||
name: Publish hex package | ||
runs-on: ubuntu-latest | ||
|
||
env: | ||
GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }} | ||
HEX_API_KEY: ${{ secrets.HEX_API_KEY }} | ||
steps: | ||
- uses: actions/checkout@v2 | ||
- name: Set up Elixir | ||
uses: erlef/setup-beam@988e02bfe678367a02564f65ca2e37726dc0268f | ||
with: | ||
elixir-version: '1.12.3' # Define the elixir version [required] | ||
otp-version: '24.1' # Define the OTP version [required] | ||
- name: Restore dependencies cache | ||
uses: actions/cache@v2 | ||
with: | ||
path: deps | ||
key: ${{ runner.os }}-mix-${{ hashFiles('**/mix.lock') }} | ||
restore-keys: ${{ runner.os }}-mix- | ||
- name: Install dependencies | ||
run: mix deps.get | ||
- name: Compile | ||
run: mix compile | ||
- name: Build hex package | ||
run: mix hex.build | ||
- name: Publish hex package | ||
run: mix hex.publish --yes |
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
Original file line number | Diff line number | Diff line change |
---|---|---|
@@ -0,0 +1,29 @@ | ||
# The directory Mix will write compiled artifacts to. | ||
/_build/ | ||
|
||
# If you run "mix test --cover", coverage assets end up here. | ||
/cover/ | ||
|
||
# The directory Mix downloads your dependencies sources to. | ||
/deps/ | ||
|
||
# Where third-party dependencies like ExDoc output generated docs. | ||
/doc/ | ||
|
||
# Ignore .fetch files in case you like to edit your project deps locally. | ||
/.fetch | ||
|
||
# If the VM crashes, it generates a dump, let's ignore it too. | ||
erl_crash.dump | ||
|
||
# Also ignore archive artifacts (built via "mix archive.build"). | ||
*.ez | ||
|
||
# Ignore package tarball (built via "mix hex.build"). | ||
stagger-*.tar | ||
|
||
# Temporary files, for example, from tests. | ||
/tmp/ | ||
|
||
# LSP | ||
.elixir_ls |
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
Original file line number | Diff line number | Diff line change |
---|---|---|
@@ -0,0 +1,4 @@ | ||
# Changelog | ||
|
||
## 0.1.7 (2022-01-26) - Initial revision | ||
|
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
Original file line number | Diff line number | Diff line change |
---|---|---|
@@ -0,0 +1,22 @@ | ||
# MIT License | ||
|
||
Copyright (c) 2022 Nick Gunn | ||
|
||
Permission is hereby granted, free of charge, to any person obtaining | ||
a copy of this software and associated documentation files (the | ||
"Software"), to deal in the Software without restriction, including | ||
without limitation the rights to use, copy, modify, merge, publish, | ||
distribute, sublicense, and/or sell copies of the Software, and to | ||
permit persons to whom the Software is furnished to do so, subject to | ||
the following conditions: | ||
|
||
The above copyright notice and this permission notice shall be | ||
included in all copies or substantial portions of the Software. | ||
|
||
THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, | ||
EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF | ||
MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND | ||
NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE | ||
LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION | ||
OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION | ||
WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. |
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
Original file line number | Diff line number | Diff line change |
---|---|---|
@@ -0,0 +1,50 @@ | ||
# Stagger | ||
|
||
[![Build Status](https://github.com/ausimian/stagger/actions/workflows/elixir.yml/badge.svg)](https://github.com/ausimian/stagger/actions?query=workflow%3A%22CI%22) | ||
[![Coverage Status](https://coveralls.io/repos/github/ausimian/stagger/badge.svg?branch=main)](https://coveralls.io/github/ausimian/stagger?branch=main) | ||
[![Hex](https://img.shields.io/hexpm/v/stagger.svg)](https://hex.pm/packages/stagger) | ||
[![Hex Docs](https://img.shields.io/badge/hex-docs-blue.svg)](https://hexdocs.pm/stagger) | ||
|
||
Point-to-point, durable message-queues as GenStage producers. | ||
|
||
Stagger enables the creation of GenStage processes that enqueue terms to simple, | ||
file-backed message-queues, allowing the producer and consumer to run independently | ||
of each other, possibly at different times. | ||
|
||
+----------+ +----------+ +----------+ +------------+ | ||
| Upstream | | MsgQueue | | MsgQueue | | Downstream | | ||
| | -> | | <- | | <---> | | | ||
| Client | | Producer | | Consumer | | Processing | | ||
+----------+ +----------+ +----------+ +------------+ | ||
| | read | ||
write | | | ||
+------+ | ||
| FILE | | ||
| | | ||
| | | ||
+------+ | ||
|
||
Your upstream client writes its events into the message-queue (provided by | ||
Stagger), which persists them to local storage. Your (GenStage) consumer, subscribes | ||
to the producer and receives events, via this local storage. | ||
## Installation | ||
|
||
The package can be installed by adding `stagger` to your list of dependencies in `mix.exs`: | ||
|
||
```elixir | ||
def deps do | ||
[ | ||
{:stagger, "~> 0.1.7"} | ||
] | ||
end | ||
``` | ||
|
||
The docs can be found at <https://hexdocs.pm/stagger>. | ||
|
||
## Copyright and License | ||
|
||
Copyright (c) 2022, Nick Gunn | ||
|
||
Stagger runtime source code is licensed under the [MIT License](LICENSE.md). | ||
Stagger test source code is licensed under the [GPL3 License](test/LICENSE). | ||
|
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
Original file line number | Diff line number | Diff line change |
---|---|---|
@@ -0,0 +1,42 @@ | ||
defmodule Mix.Tasks.Tag do | ||
@moduledoc "Tags the current commit with the version specified in the Mix file" | ||
@shortdoc "Tag the current commit" | ||
|
||
use Mix.Task | ||
|
||
def run(args) do | ||
# Called just for effect, raise NoProjectError if no project | ||
Mix.Project.get!() | ||
|
||
project = Mix.Project.config() | ||
stated = Version.parse!(project[:version]) | ||
actual = Version.parse!(git_version()) | ||
|
||
case Version.compare(stated, actual) do | ||
:lt -> | ||
Mix.Shell.IO.error("Stated version (#{stated}) is less than current commit (#{actual}") | ||
:eq -> | ||
Mix.Shell.IO.info("Commit already at v#{stated}") | ||
:gt -> | ||
force = if Enum.member?(args, "--force"), do: "-f ", else: "" | ||
cmd = "git tag " <> force <> "-a -m v#{stated} v#{stated}" | ||
if Enum.member?(args, "--dry-run") do | ||
Mix.Shell.IO.info("Dry run: #{cmd}") | ||
else | ||
Mix.Shell.IO.cmd(cmd) | ||
Mix.Shell.IO.info("Tagged current commit at v#{stated}") | ||
end | ||
end | ||
|
||
end | ||
|
||
defp git_version do | ||
case System.cmd("git", ~w[describe --dirty=+dirty], stderr_to_stdout: true) do | ||
{"v" <> version, 0} -> | ||
version | ||
|> String.trim | ||
_ -> | ||
"0.0.0-dev" | ||
end | ||
end | ||
end |
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
Original file line number | Diff line number | Diff line change |
---|---|---|
@@ -0,0 +1,129 @@ | ||
defmodule Stagger do | ||
@moduledoc ~S""" | ||
Point-to-point, durable message-queues as GenStage producers. | ||
Stagger enables the creation of GenStage processes that enqueue terms to simple, | ||
file-backed message-queues, allowing the producer and consumer to run independently | ||
of each other, possibly at different times. | ||
+----------+ +----------+ +----------+ +------------+ | ||
| Upstream | | MsgQueue | | MsgQueue | | Downstream | | ||
| | -> | | <- | | <---> | | | ||
| Client | | Producer | | Consumer | | Processing | | ||
+----------+ +----------+ +----------+ +------------+ | ||
| | read | ||
write | | | ||
+------+ | ||
| FILE | | ||
| | | ||
| | | ||
+------+ | ||
Your upstream client writes its events into the message-queue (provided by | ||
Stagger), which persists them to local storage. Your (GenStage) consumer, subscribes | ||
to the producer and receives events, via this local storage. | ||
## Producers | ||
Upstream clients must first open their message-queue, via `open/1`, and then use the | ||
resulting process to enqueue writes, via `write/2`. | ||
{:ok, pid} = Stagger.open("/path/to/msg/queue") | ||
... | ||
:ok = Stagger.write(pid, "foo") | ||
:ok = Stagger.write(pid, "bar") | ||
:ok = Stagger.write(pid, "baz") | ||
The process created via `open/1` is the GenStage MsgQueue - by writing entries to it, | ||
it will satisfy demand from a downstream consumer. | ||
## Consumers | ||
Downstream clients are GenStage consumers. They must also open the message-queue, via | ||
`open/1` and then subscribe use existing GenStage subscription facilities: | ||
def init(args) do | ||
{:ok, pid} = Stagger.open("/path/to/msg/queue") | ||
{:ok, sub} = GenStage.sync_subscribe(self(), to: pid, ack: last_processed()) | ||
... | ||
end | ||
def handle_events(events, _from, stage) do | ||
... | ||
end | ||
## Sequence numbers | ||
Sequence numbers are used to control the events seen by a subscriber. Every event | ||
delivered to a consumer is a 2-tuple of `{seqno, msg}` and it is the consumer's | ||
responsibility to successfully record this sequence number as having been | ||
processed. | ||
A consumer must indicate its last-processed sequence number by passing `ack: N` in | ||
the subscription options (pass `ack: 0` when no such number exists) whenever it | ||
(re)subscribes. Event delivery will resume from the Nth + 1 event. | ||
Every message _written_ to the message-queue is assigned an incrementing sequence number | ||
by the Stagger process. When an existing message queue is re-opened, the process will | ||
first recover the last written number, using that as the base for any subsequent writes. | ||
## Purging | ||
In order to prevent unconstrained growth of the message-queue file, a consumer may | ||
periodically purge the queue of old entries by passing a `purge: N` option when it | ||
(re)subscribes e.g: | ||
last = last_processed() | ||
{:ok, sub} = GenStage.sync_subscribe(self(), to: pid, ack: last, purge: last) | ||
All entries _up to and including_ N are removed from the head of message-queue file. | ||
The value of N will be capped to no more than the value of the last ack'd message. | ||
To summarize: | ||
- `ack: N` determines that the next delivered message will have a seqno of N + 1 | ||
- `purge: M` is a hint to the producer to remove messages 1..M from the head of | ||
the message queue. | ||
## Why not RabbitMQ? | ||
If you think you need something like RabbitMQ, you probably do :-). Stagger is | ||
intended to be a lightweight durable message queue with minimal dependencies. | ||
""" | ||
|
||
@doc """ | ||
Open a message-queue file, returning the pid responsible for managing it. | ||
The resulting pid can be used by upstream clients to enqueue messages via `write/2`, or | ||
may be used as the target of a GenStage subscribe operation. | ||
The following option may be passed to the function: | ||
* `hibernate_after: N` - After a period of _N_ milliseconds, the returned process will | ||
hibernate. If unspecified, defaults to 15 seconds. Pass `hibernate_after: :infinite` | ||
to inhibit this behaviour. This option only takes effect if the process managing the | ||
queue is created by the call to `open/2`. | ||
""" | ||
@spec open(binary, Keyword.t) :: :ignore | {:error, any} | {:ok, any} | {:ok, pid, any} | ||
def open(path, opts \\ []) when is_binary(path) do | ||
args = Map.new(opts) |> Map.put(:path, path) | ||
case DynamicSupervisor.start_child(Stagger.MsgQueueSupervisor, {Stagger.MsgQueue, args}) do | ||
{:ok, pid} -> | ||
{:ok, pid} | ||
{:error, {:already_started, pid}} -> | ||
{:ok, pid} | ||
error -> | ||
error | ||
end | ||
end | ||
|
||
@doc """ | ||
Write a term to the message-queue. | ||
""" | ||
@spec write(pid :: atom | pid | {atom, any} | {:via, atom, any}, term :: any, timeout :: :infinite | non_neg_integer()) :: :ok | {:error, any} | ||
def write(pid, term, timeout \\ 5000) do | ||
Stagger.MsgQueue.write(pid, term, timeout) | ||
end | ||
|
||
end |
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
Original file line number | Diff line number | Diff line change |
---|---|---|
@@ -0,0 +1,18 @@ | ||
defmodule Stagger.Application do | ||
@moduledoc false | ||
|
||
use Application | ||
|
||
@impl true | ||
def start(_type, _args) do | ||
children = [ | ||
# A registry used to hold each MsgQueue, keyed by the path of the MsgQueue file | ||
%{id: Stagger.MsgQueueRegistry, start: {Registry, :start_link, [[keys: :unique, name: Stagger.MsgQueueRegistry]]}}, | ||
# The supervisor for the MsgQueue processes | ||
{DynamicSupervisor, strategy: :one_for_one, name: Stagger.MsgQueueSupervisor}, | ||
] | ||
|
||
opts = [strategy: :one_for_one, name: Stagger.Supervisor] | ||
Supervisor.start_link(children, opts) | ||
end | ||
end |
Oops, something went wrong.