feat: add etcd elector for gocron

.github/FUNDING.yml

@@ -0,0 +1,12 @@
+# These are supported funding model platforms
+
+github: # Replace with up to 4 GitHub Sponsors-enabled usernames e.g., [user1, user2]
+patreon: # Replace with a single Patreon username
+open_collective: go-co-op
+ko_fi: # Replace with a single Ko-fi username
+tidelift: # Replace with a single Tidelift platform-name/package-name e.g., npm/babel
+community_bridge: # Replace with a single Community Bridge project-name e.g., cloud-foundry
+liberapay: # Replace with a single Liberapay username
+issuehunt: # Replace with a single IssueHunt username
+otechie: # Replace with a single Otechie username
+custom: # Replace with up to 4 custom sponsorship URLs e.g., ['link1', 'link2']

.github/dependabot.yml

@@ -0,0 +1,18 @@
+# To get started with Dependabot version updates, you'll need to specify which
+# package ecosystems to update and where the package manifests are located.
+# Please see the documentation for all configuration options:
+# https://help.github.com/github/administering-a-repository/configuration-options-for-dependency-updates
+
+version: 2
+updates:
+  # Maintain dependencies for GitHub Actions
+  - package-ecosystem: "github-actions"
+    directory: "/"
+    schedule:
+      interval: "weekly"
+
+  # Maintain Go dependencies
+  - package-ecosystem: "gomod"
+    directory: "/"
+    schedule:
+      interval: "weekly"

.github/workflows/codeql-analysis.yml

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+# For most projects, this workflow file will not need changing; you simply need
+# to commit it to your repository.
+#
+# You may wish to alter this file to override the set of languages analyzed,
+# or to provide custom queries or build logic.
+#
+# ******** NOTE ********
+# We have attempted to detect the languages in your repository. Please check
+# the `language` matrix defined below to confirm you have the correct set of
+# supported CodeQL languages.
+#
+name: "CodeQL"
+
+on:
+  push:
+    branches: [ main ]
+  pull_request:
+    # The branches below must be a subset of the branches above
+    branches: [ main ]
+  schedule:
+    - cron: '34 7 * * 1'
+
+jobs:
+  analyze:
+    name: Analyze
+    runs-on: ubuntu-latest
+
+    strategy:
+      fail-fast: false
+      matrix:
+        language: [ 'go' ]
+        # CodeQL supports [ 'cpp', 'csharp', 'go', 'java', 'javascript', 'python' ]
+        # Learn more:
+        # https://docs.github.com/en/free-pro-team@latest/github/finding-security-vulnerabilities-and-errors-in-your-code/configuring-code-scanning#changing-the-languages-that-are-analyzed
+
+    steps:
+    - name: Checkout repository
+      uses: actions/checkout@v3
+
+    # Initializes the CodeQL tools for scanning.
+    - name: Initialize CodeQL
+      uses: github/codeql-action/init@v2
+      with:
+        languages: ${{ matrix.language }}
+        # If you wish to specify custom queries, you can do so here or in a config file.
+        # By default, queries listed here will override any specified in a config file.
+        # Prefix the list here with "+" to use these queries and those in the config file.
+        # queries: ./path/to/local/query, your-org/your-repo/queries@main
+
+    # Autobuild attempts to build any compiled languages  (C/C++, C#, or Java).
+    # If this step fails, then you should remove it and run the build manually (see below)
+    - name: Autobuild
+      uses: github/codeql-action/autobuild@v2
+
+    # ℹ️ Command-line programs to run using the OS shell.
+    # 📚 https://git.io/JvXDl
+
+    # ✏️ If the Autobuild fails above, remove it and uncomment the following three lines
+    #    and modify them (or add more) to build your code if your project
+    #    uses a compiled language
+
+    #- run: |
+    #   make bootstrap
+    #   make release
+
+    - name: Perform CodeQL Analysis
+      uses: github/codeql-action/analyze@v2

.github/workflows/go_test.yml

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+on: [push]
+name: golangci-lint
+jobs:
+  golangci:
+    strategy:
+      matrix:
+        go-version:
+          - "1.20"
+    name: lint and test
+    runs-on: ubuntu-latest
+    services:
+      etcd:
+        image: bitnami/etcd:3.5.5
+        env:
+          ALLOW_NONE_AUTHENTICATION: yes
+          ETCD_ADVERTISE_CLIENT_URLS: http://127.0.0.1:2379
+          ETCDCTL_API: 3
+        ports:
+          - 2379:2379
+          - 2380:2380
+    steps:
+      - name: Checkout code
+        uses: actions/checkout@v3
+      - name: golangci-lint
+        uses: golangci/[email protected]
+        with:
+          version: v1.51.2
+      - name: Install Go
+        uses: actions/setup-go@v4
+        with:
+          go-version: ${{ matrix.go-version }}
+      - name: test
+        run: make test

CONTRIBUTING.md

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+# Contributing to gocron
+
+Thank you for coming to contribute to gocron! We welcome new ideas, PRs and general feedback.
+
+## Reporting Bugs
+
+If you find a bug then please let the project know by opening an issue after doing the following:
+
+- Do a quick search of the existing issues to make sure the bug isn't already reported
+- Try and make a minimal list of steps that can reliably reproduce the bug you are experiencing
+- Collect as much information as you can to help identify what the issue is (project version, configuration files, etc)
+
+## Suggesting Enhancements
+
+If you have a use case that you don't see a way to support yet, we would welcome the feedback in an issue. Before opening the issue, please consider:
+
+- Is this a common use case?
+- Is it simple to understand?
+
+You can help us out by doing the following before raising a new issue:
+
+- Check that the feature hasn't been requested already by searching existing issues
+- Try and reduce your enhancement into a single, concise and deliverable request, rather than a general idea
+- Explain your own use cases as the basis of the request
+
+## Adding Features
+
+Pull requests are always welcome. However, before going through the trouble of implementing a change it's worth creating a bug or feature request issue.
+This allows us to discuss the changes and make sure they are a good fit for the project.
+
+Please always make sure a pull request has been:
+
+- Unit tested with `make test`
+- Linted with `make lint`
+- Vetted with `make vet`
+- Formatted with `make fmt` or validated with `make check-fmt`
+
+## Writing Tests
+
+Tests should follow the [table driven test pattern](https://dave.cheney.net/2013/06/09/writing-table-driven-tests-in-go). See other tests in the code base for additional examples.

Makefile

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+.PHONY: fmt check-fmt lint vet test
+
+GO_PKGS   := $(shell go list -f {{.Dir}} ./...)
+
+fmt:
+	@go list -f {{.Dir}} ./... | xargs -I{} gofmt -w -s {}
+
+lint:
+	@golangci-lint run
+
+test:
+	@go test -v $(GO_FLAGS) -count=1 $(GO_PKGS)

README.md

@@ -1 +1,71 @@
-# gocron-etcd-elector
+# gocron-etcd-elector
+
+## install
+
+```
+go get github.com/go-co-op/gocron-etcd-elector
+```
+
+## usage
+
+Here is an example usage that would be deployed in multiple instances.
+
+```go
+package main
+
+import (
+	"context"
+	"fmt"
+	"os"
+	"os/signal"
+	"syscall"
+	"time"
+
+	"github.com/go-co-op/gocron"
+	elector "github.com/go-co-op/gocron-etcd-elector"
+)
+
+func main() {
+	cfg := elector.Config{
+		Endpoints:   []string{"http://127.0.0.1:2379"},
+		DialTimeout: 3 * time.Second,
+	}
+
+	el, err := elector.NewElector(context.Background(), cfg, elector.WithTTL(10))
+	if err != nil {
+		panic(err)
+	}
+
+	go func() {
+		for {
+			err := el.Start("/gocron/elector")
+			if err == elector.ErrClosed {
+				return
+			}
+
+			time.Sleep(1e9)
+		}
+	}()
+
+	s := gocron.NewScheduler(time.UTC)
+	s.WithDistributedElector(el)
+
+	s.Every("1s").Do(func() {
+		if el.IsLeader(context.TODO()) == nil {
+			fmt.Println("the current instance is leader")
+		} else {
+			fmt.Println("the current leader is", el.GetLeaderID())
+		}
+
+		fmt.Println("call 1s")
+	})
+
+	s.StartAsync()
+
+	c := make(chan os.Signal, 1)
+	signal.Notify(c, syscall.SIGINT, syscall.SIGQUIT, syscall.SIGTERM)
+	<-c
+
+	fmt.Println("exit")
+}
+```

SECURITY.md

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+# Security Policy
+
+## Supported Versions
+
+The current plan is to maintain version 1 as long as possible incorporating any necessary security patches.
+
+| Version | Supported          |
+| ------- | ------------------ |
+| 1.x.x   | :white_check_mark: |
+
+## Reporting a Vulnerability
+
+Vulnerabilities can be reported by [opening an issue](https://github.com/go-co-op/gocron/issues/new/choose) or reaching out on Slack: [<img src="https://img.shields.io/badge/gophers-gocron-brightgreen?logo=slack">](https://gophers.slack.com/archives/CQ7T0T1FW)
+
+We will do our best to addrerss any vulnerabilities in an expeditious manner. 

docker-compose.yml

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+version: '3'
+
+services:
+  docker-etcd:
+    hostname: etcd
+    image: bitnami/etcd:3.5.5
+    environment:
+      - ALLOW_NONE_AUTHENTICATION=yes
+      - ETCD_ADVERTISE_CLIENT_URLS=http://127.0.0.1:2379
+      - ETCDCTL_API=3
+    ports:
+      - "2379:2379"
+      - "2380:2380"