feat: implement jobqueue

.envrc

+source_url "https://raw.githubusercontent.com/cachix/devenv/d1f7b48e35e6dee421cfd0f51481d17f77586997/direnvrc" "sha256-YBzqskFZxmNb3kYVoKD9ZixoPXJh1C9ZvTLGFRkauZ0="
+
+use devenv
\ No newline at end of file

.gitignore

+
+# Devenv
+.devenv*
+devenv.local.nix
+
+# direnv
+.direnv
+
+# pre-commit
+.pre-commit-config.yaml
+
+smell.go

.gitlab-ci.yml

+
+# THIS FILE IS AUTOGENERATED BY THE DEVENVSHELL
+# DO NOT EDIT THIS FILE MANUALLY
+# INSTEAD EDIT THE DEVENVSHELL CONFIGURATION FILE devenv.nix
+# AND OPEN A SHELL WITH THE COMMAND devenv shell
+#
+
+image: docker-registry.schukai.com:443/nixos-ci-devenv:latest
+
+services:
+  - docker:dind
+
+variables:
+  # The repo name as used in
+  # https://github.com/nix-community/NUR/blob/master/repos.json
+  NIXOS_VERSION: "23.05"
+  NIXPKGS_ALLOW_UNFREE: "1"
+  NIXPKGS_ALLOW_INSECURE: "1"
+  DOCKER_DRIVER: overlay2
+  GIT_DEPTH: 10
+
+stages:
+  - test
+  - deploy 
+
+before_script:
+  - nix shell nixpkgs#coreutils-full -c mkdir -p /certs/client/
+  - nix shell nixpkgs#coreutils-full -c ln -fs /etc/ssl/certs/ca-bundle.crt /certs/client/ca.pem
+  - echo > .env-gitlab-ci
+  - variables=("HOME=$HOME" "CI_COMMIT_REF_NAME=$CI_COMMIT_REF_NAME" "CI_REPOSITORY_URL=$CI_REPOSITORY_URL" "GITLAB_TOKEN=$GITLAB_TOKEN" "CI_JOB_TOKEN=$CI_JOB_TOKEN" "GITLAB_USER_EMAIL=$GITLAB_USER_EMAIL" "GITLAB_USER_NAME=\"$GITLAB_USER_NAME\"" "CI_REGISTRY_USER=$CI_REGISTRY_USER" "CI_PROJECT_ID=$CI_PROJECT_ID" "CI_PROJECT_DIR=$CI_PROJECT_DIR" "CI_API_V4_URL=$CI_API_V4_URL" "CI_PROJECT_NAME=$CI_PROJECT_NAME" "CI_COMMIT_SHORT_SHA=$CI_COMMIT_SHORT_SHA"); for var in "${variables[@]}"; do echo "$var" >> .env-gitlab-ci; done
+  - cat .env-gitlab-ci
+
+after_script:
+  - if [ -f .env-gitlab-ci ]; then rm .env-gitlab-ci; fi
+
+test:
+  stage: test
+  tags:
+    - nixos
+  script:
+    - devenv shell test-lib
+
+  cache:
+    - key: nixos
+      paths:
+        - /nix/store
+  
+  artifacts:
+    paths:
+      - dist
+
+deploy:
+  stage: deploy
+  tags:
+    - nixos
+  script:
+    - devenv shell -c deploy-lib
+
+  when: on_success
+
+  cache:
+    - key: nixos
+      paths:
+        - /nix/store
+
+
+  artifacts:
+    paths:
+      - dist   

.idea/.gitignore

+# Default ignored files
+/shelf/
+/workspace.xml
+# Editor-based HTTP Client requests
+/httpRequests/
+# Datasource local storage ignored files
+/dataSources/
+/dataSources.local.xml

.idea/aws.xml

+<?xml version="1.0" encoding="UTF-8"?>
+<project version="4">
+  <component name="accountSettings">
+    <option name="activeProfile" value="profile:default" />
+    <option name="activeRegion" value="eu-west-1" />
+    <option name="recentlyUsedProfiles">
+      <list>
+        <option value="profile:default" />
+      </list>
+    </option>
+    <option name="recentlyUsedRegions">
+      <list>
+        <option value="eu-west-1" />
+      </list>
+    </option>
+  </component>
+</project>
\ No newline at end of file

.idea/job-queues.iml

+<?xml version="1.0" encoding="UTF-8"?>
+<module type="JAVA_MODULE" version="4">
+  <component name="Go" enabled="true" />
+  <component name="NewModuleRootManager" inherit-compiler-output="true">
+    <exclude-output />
+    <content url="file://$MODULE_DIR$" />
+    <orderEntry type="inheritedJdk" />
+    <orderEntry type="sourceFolder" forTests="false" />
+  </component>
+</module>
\ No newline at end of file

.idea/markdown.xml

+<?xml version="1.0" encoding="UTF-8"?>
+<project version="4">
+  <component name="MarkdownSettings">
+    <enabledExtensions>
+      <entry key="MermaidLanguageExtension" value="false" />
+      <entry key="PlantUMLLanguageExtension" value="true" />
+    </enabledExtensions>
+  </component>
+</project>
\ No newline at end of file

.idea/misc.xml

+<?xml version="1.0" encoding="UTF-8"?>
+<project version="4">
+  <component name="ProjectRootManager">
+    <output url="file://$PROJECT_DIR$/out" />
+  </component>
+</project>
\ No newline at end of file

.idea/modules.xml

+<?xml version="1.0" encoding="UTF-8"?>
+<project version="4">
+  <component name="ProjectModuleManager">
+    <modules>
+      <module fileurl="file://$PROJECT_DIR$/.idea/job-queues.iml" filepath="$PROJECT_DIR$/.idea/job-queues.iml" />
+    </modules>
+  </component>
+</project>
\ No newline at end of file

.idea/vcs.xml

+<?xml version="1.0" encoding="UTF-8"?>
+<project version="4">
+  <component name="VcsDirectoryMappings">
+    <mapping directory="" vcs="Git" />
+  </component>
+</project>
\ No newline at end of file

LICENSE

+Copyright (C) 2022 by schukai GmbH. 
+
+This program is free software: you can redistribute it and/or modify
+it under the terms of the GNU Affero General Public License as published
+by the Free Software Foundation, either version 3 of the License.
+
+This program is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+GNU Affero General Public License for more details.
+
+You should have received a copy of the GNU Affero General Public License
+along with this program.  If not, see <https://www.gnu.org/licenses/>.
+

README.md

 # Job Queues
 
-The jobque allows the processing of tasks.
+The `jobQueue` library in Go aims to serve as a Cron replacement, enabling the scheduled and event-driven execution of tasks in an organized manner.
\ No newline at end of file
+
+## Library Requirements
+
+### Core Requirements
+
+1. **Job Management Structure**: A structure to catalog all jobs, providing methods to add and remove jobs.
+
+2. **YAML Import**: A function to import job definitions from a YAML file.
+
+3. **Job Exclusivity**: Jobs should be either concurrently runnable or exclusive.
+
+4. **System Resource Monitoring**: Real-time monitoring of system resources like CPU, memory, etc., consumed by the jobs.
+
+5. **Priority and Distribution**: Each job should have a priority. Jobs should also be evenly distributed across available resources.
+
+6. **Single and Recurring Jobs**: Support for both one-time and recurring jobs.
+
+7. **Logging**: Each job should have a log written that includes Process ID, memory usage, start time, end time, and exit code.
+
+8. **Priority Escalation**: If a job is not run due to its priority, its priority should escalate over time.
+
+### Additional Requirements
+
+1. **Error Handling**: Mechanisms for effective error handling, especially for failed or terminated jobs.
+
+2. **Notification System**: Optionally, an interface for notifications on job failures or completions.
+
+3. **Resource Limits**: Ability to set resource limits per job.
+
+4. **Job Dependencies**: Optional support for jobs that depend on the successful completion of other jobs.
+
+5. **Testability**: The library should be easy to test, ideally via unit tests.
+
+6. **Documentation**: Comprehensive API documentation and a guide on how the library works.
+
+
+
+## Documentation 
+
+### `JobData` Structure
+
+#### Fields
+
+- **Id (JobIDType)**
+    - Unique identifier for the job.
+
+- **Priority (int)**
+    - The priority level of the job in the queue.
+
+- **Exclusive (bool)**
+    - Specifies whether the job should be executed exclusively or not.
+
+- **MaxRuns (int)**
+    - The maximum number of times the job should be executed.
+
+- **Concurrency (int)**
+    - The maximum number of concurrent executions of the job.
+
+- **LastRun (time.Time)**
+    - Timestamp for when the job was last executed.
+
+- **NextRun (time.Time)**
+    - Timestamp for the next scheduled execution of the job.
+
+- **Logs ([]JobLog)**
+    - An array of log entries for the job.
+
+- **Schedule (string)**
+    - A cron expression that defines the execution schedule.
+
+- **Status (JobStatus)**
+    - The current status of the job (e.g., `Running`, `Completed`).
+
+- **Timeout (time.Duration)**
+    - The maximum duration the job is allowed to run.
+
+- **Retries (int)**
+    - The number of times the job will be retried if it fails.
+
+- **RetryDelay (time.Duration)**
+    - The delay before retrying the job if it fails.
+
+- **ResourceLimits (struct)**
+    - Resource limits for CPU and Memory.
+
+        - **CPULimit (float64)**
+            - CPU limit for the job.
+
+        - **MemoryLimit (uint64)**
+            - Memory limit for the job.
+
+- **Dependencies ([]JobIDType)**
+    - List of job IDs this job depends on.
+
+- **Tags ([]string)**
+    - Tags associated with the job for easier categorization.
+
+- **Metadata (map[string]interface{})**
+    - Metadata for extending the structure with additional information.
+
+- **Stats (JobStats)**
+    - Job-related statistics.
+
+### `Job` Structure
+
+Inherits fields from `JobData` and adds additional functional fields.
+
+#### Fields
+
+- **Runnable (Runnable)**
+    - A function or method that defines the action of the job. This is what gets executed.
+
+- **scheduleImpl (cron.Schedule)**
+    - Internal cron schedule implementation that interprets the `Schedule` string in `JobData`.
+
+- **TelemetryHooks ([]func(*JobLog))**
+    - An array of functions that will be called for telemetry during the job's execution. These hooks can update a `JobLog` object.
+
+- **Failover (func() error)**
+    - A function that gets called if the primary execution fails for some reason. It's meant for fail over mechanisms.
+
+- **ctx (context.Context)**
+    - A context that can carry deadlines, cancellations, and other request-scoped values across API boundaries and between processes.
+
+- **mu (sync.Mutex)**
+    - Mutex for synchronizing access to the job's fields, making the job safe for concurrent use.
+

Taskfile.yml

+
+# THIS FILE IS AUTOGENERATED BY THE DEVENVSHELL
+# DO NOT EDIT THIS FILE MANUALLY
+# INSTEAD EDIT THE DEVENVSHELL CONFIGURATION FILE devenv.nix 
+# AND OPEN A SHELL WITH THE COMMAND devenv shell
+#
+# Information about the task runner can be found here:
+# https://taskfile.dev
+
+version: '3'
+
+tasks:
+  default:
+    cmds:
+      - task --list
+    silent: true
+    
+  test:
+    desc: Execute unit tests in Go.
+    cmds:
+      - echo "Execute unit tests in Go."
+      - go test -cover -v ./...
+      - go test -bench -v ./...
+      - go test -race -v ./...
+
+  test-fuzz:
+    desc: Conduct fuzzing tests.#
+    cmds:  
+      - echo "Conduct fuzzing tests."
+      - go test -v -fuzztime=30s -fuzz=Fuzz ./...
+
+  add-licenses:
+    desc: Attach license headers to Go files.
+    cmds:
+      - echo "Attach license headers to Go files."
+      - go install github.com/google/addlicense@latest
+      - addlicense -c "schukai GmbH" -s -l "AGPL-3.0" ./*.go
+    silent: true
+    
+  check-licenses:
+    desc: Check license headers of Go files.
+    silent: true
+    cmds:
+      - go-licenses save "$(get-go-default-packages)"  --ignore "gitlab.schukai.com"  --force --save_path ${DEVENV_ROOT}/licenses/
+
+  check:
+    desc: Confirm repository status.
+    cmds:
+      - git diff-index --quiet HEAD || (echo "There are uncommitted changes after running make. Please commit or stash them before running make."; exit 1)
+    silent: true
+
+  commit:
+    desc: Commit changes to the repository.
+    aliases:
+      - c
+      - ci
+      - git-commit
+    cmds:
+      - do-git-commit

cmd/main.go

+package main
+
+import (
+	"fmt"
+	jobqueue "gitlab.schukai.com/oss/libraries/go/services/job-queues.git"
+)
+
+func main() {
+	jq := jobqueue.NewJobs()
+	if jq == nil {
+		panic("NewJobs returned nil")
+	}
+
+	// Hinzufügen eines neuen Jobs
+	err := jq.AddJob(jobqueue.JobSpecification{
+		Id:       "test",
+		Priority: 1,
+	}, &jobqueue.ExternalProcessRunner{
+		Command: "sleep",
+		Args:    []string{"1"},
+	})
+	if err != nil {
+		panic(err)
+	}
+
+	// Abrufen aller Jobs
+	allJobs := jq.GetJobs()
+	fmt.Println("Alle Jobs:", allJobs)
+
+	// Entfernen eines Jobs
+	removed, err := jq.RemoveJob("test")
+	if err != nil {
+		panic(err)
+	}
+	if removed {
+		fmt.Println("Job wurde entfernt.")
+	}
+
+}

devenv.lock

+{
+  "nodes": {
+    "devenv": {
+      "locked": {
+        "dir": "src/modules",
+        "lastModified": 1696344641,
+        "narHash": "sha256-cfGsdtDvzYaFA7oGWSgcd1yST6LFwvjMcHvtVj56VcU=",
+        "owner": "cachix",
+        "repo": "devenv",
+        "rev": "05e26941f34486bff6ebeb4b9c169b6f637f1758",
+        "type": "github"
+      },
+      "original": {
+        "dir": "src/modules",
+        "owner": "cachix",
+        "repo": "devenv",
+        "type": "github"
+      }
+    },
+    "flake-compat": {
+      "flake": false,
+      "locked": {
+        "lastModified": 1673956053,
+        "narHash": "sha256-4gtG9iQuiKITOjNQQeQIpoIB6b16fm+504Ch3sNKLd8=",
+        "owner": "edolstra",
+        "repo": "flake-compat",
+        "rev": "35bb57c0c8d8b62bbfd284272c928ceb64ddbde9",
+        "type": "github"
+      },
+      "original": {
+        "owner": "edolstra",
+        "repo": "flake-compat",
+        "type": "github"
+      }
+    },
+    "flake-utils": {
+      "inputs": {
+        "systems": "systems"
+      },
+      "locked": {
+        "lastModified": 1685518550,
+        "narHash": "sha256-o2d0KcvaXzTrPRIo0kOLV0/QXHhDQ5DTi+OxcjO8xqY=",
+        "owner": "numtide",
+        "repo": "flake-utils",
+        "rev": "a1720a10a6cfe8234c0e93907ffe81be440f4cef",
+        "type": "github"
+      },
+      "original": {
+        "owner": "numtide",
+        "repo": "flake-utils",
+        "type": "github"
+      }
+    },
+    "gitignore": {
+      "inputs": {
+        "nixpkgs": [
+          "pre-commit-hooks",
+          "nixpkgs"
+        ]
+      },
+      "locked": {
+        "lastModified": 1660459072,
+        "narHash": "sha256-8DFJjXG8zqoONA1vXtgeKXy68KdJL5UaXR8NtVMUbx8=",
+        "owner": "hercules-ci",
+        "repo": "gitignore.nix",
+        "rev": "a20de23b925fd8264fd7fad6454652e142fd7f73",
+        "type": "github"
+      },
+      "original": {
+        "owner": "hercules-ci",
+        "repo": "gitignore.nix",
+        "type": "github"
+      }
+    },
+    "nixpkgs": {
+      "locked": {
+        "lastModified": 1696374741,
+        "narHash": "sha256-gt8B3G0ryizT9HSB4cCO8QoxdbsHnrQH+/BdKxOwqF0=",
+        "owner": "nixos",
+        "repo": "nixpkgs",
+        "rev": "8a4c17493e5c39769f79117937c79e1c88de6729",
+        "type": "github"
+      },
+      "original": {
+        "owner": "nixos",
+        "ref": "nixos-23.05",
+        "repo": "nixpkgs",
+        "type": "github"
+      }
+    },
+    "nixpkgs-stable": {
+      "locked": {
+        "lastModified": 1685801374,
+        "narHash": "sha256-otaSUoFEMM+LjBI1XL/xGB5ao6IwnZOXc47qhIgJe8U=",
+        "owner": "NixOS",
+        "repo": "nixpkgs",
+        "rev": "c37ca420157f4abc31e26f436c1145f8951ff373",
+        "type": "github"
+      },
+      "original": {
+        "owner": "NixOS",
+        "ref": "nixos-23.05",
+        "repo": "nixpkgs",
+        "type": "github"
+      }
+    },
+    "nixpkgs_2": {
+      "locked": {
+        "lastModified": 1696374741,
+        "narHash": "sha256-gt8B3G0ryizT9HSB4cCO8QoxdbsHnrQH+/BdKxOwqF0=",
+        "owner": "NixOS",
+        "repo": "nixpkgs",
+        "rev": "8a4c17493e5c39769f79117937c79e1c88de6729",
+        "type": "github"
+      },
+      "original": {
+        "id": "nixpkgs",
+        "ref": "nixos-23.05",
+        "type": "indirect"
+      }
+    },
+    "pre-commit-hooks": {
+      "inputs": {
+        "flake-compat": "flake-compat",
+        "flake-utils": "flake-utils",
+        "gitignore": "gitignore",
+        "nixpkgs": [
+          "nixpkgs"
+        ],
+        "nixpkgs-stable": "nixpkgs-stable"
+      },
+      "locked": {
+        "lastModified": 1696516544,
+        "narHash": "sha256-8rKE8Je6twTNFRTGF63P9mE3lZIq917RAicdc4XJO80=",
+        "owner": "cachix",
+        "repo": "pre-commit-hooks.nix",
+        "rev": "66c352d33e0907239e4a69416334f64af2c685cc",
+        "type": "github"
+      },
+      "original": {
+        "owner": "cachix",
+        "repo": "pre-commit-hooks.nix",
+        "type": "github"
+      }
+    },
+    "root": {
+      "inputs": {
+        "devenv": "devenv",
+        "nixpkgs": "nixpkgs",
+        "pre-commit-hooks": "pre-commit-hooks",
+        "version": "version"
+      }
+    },
+    "systems": {
+      "locked": {
+        "lastModified": 1681028828,
+        "narHash": "sha256-Vy1rq5AaRuLzOxct8nz4T6wlgyUR7zLU309k9mBC768=",
+        "owner": "nix-systems",
+        "repo": "default",
+        "rev": "da67096a3b9bf56a91d16901293e51ba5b49a27e",
+        "type": "github"
+      },
+      "original": {
+        "owner": "nix-systems",
+        "repo": "default",
+        "type": "github"
+      }
+    },
+    "version": {
+      "inputs": {
+        "nixpkgs": "nixpkgs_2"
+      },
+      "locked": {
+        "lastModified": 1690668568,
+        "narHash": "sha256-jzixQKFFW4oxO0S4GYqbkFCXzhBd6com6Z9+MtVKakU=",
+        "ref": "refs/heads/master",
+        "rev": "3838f03165b726e47d586c04a1821749375e1001",
+        "revCount": 37,
+        "type": "git",
+        "url": "https://gitlab.schukai.com/oss/utilities/version.git"
+      },
+      "original": {
+        "type": "git",
+        "url": "https://gitlab.schukai.com/oss/utilities/version.git"
+      }
+    }
+  },
+  "root": "root",
+  "version": 7
+}

devenv.nix

+{ pkgs, inputs, phps, lib, config, modulesPath, ... }:
+
+{
+  # https://devenv.sh/packages/
+  packages = with pkgs; [
+    inputs.version.defaultPackage."${builtins.currentSystem}"
+    appimage-run
+    blackbox
+    blackbox-terminal
+    coreutils-full
+    dbeaver
+    delve
+    dialog
+    drill
+    exa
+    fd
+    fd
+    gcc12
+    gdlv
+    git
+    glab
+    gnugrep
+    gnumake
+    gnused
+    go-licenses
+    go-task
+    gum
+    httpie
+    hurl
+    jq
+    libffi
+    logrotate
+    meld
+    memcached
+    netcat
+    nixfmt
+    procps
+    ranger
+    unixtools.xxd
+    unzip
+    util-linux
+    wget
+    zlib
+    nodePackages.mermaid-cli
+    feh
+    
+  ];
+
+  # https://devenv.sh/languages/
+  # languages.nix.enable = true;
+  languages = { go = { enable = true; }; };
+
+  difftastic.enable = true;
+
+  scripts.draw-graph.exec = ''
+  echo -e "Enter Meirmaid graph definition. ''${RED}End with Ctrl+D''${RESET}\n"  
+  diagram=$(${pkgs.gum}/bin/gum write --placeholder "Enter Meirmaid graph definition. End with Ctrl+D")
+  
+  tmpOutput=$(mktemp).png
+  
+  echo "$diagram" | ${pkgs.nodePackages.mermaid-cli}/bin/mmdc -i - -o "$tmpOutput"
+  ${pkgs.feh}/bin/feh $tmpOutput
+  
+  # should delte the file, but does not work ask with gum
+  ${pkgs.gum}/bin/gum confirm "Delete temporary file?"
+    if [ $? -eq 0 ]; then
+       rm "$tmpOutput"
+       else
+         echo "not deleting; file is at $tmpOutput"
+    fi    
+    
+    
+  
+  
+  '';
+  
+  scripts.get-go-default-packages.exec = ''
+    #!${pkgs.bash}/bin/bash
+    echo $(awk -F ' ' '/^module / { print $2 }' go.mod)
+  '';
+
+  # This script is executed when the app is built
+  # You can use it to build the app  
+  scripts.test-lib.exec = ''
+    #!${pkgs.bash}/bin/bash
+    #set -euo pipefail
+    set -x
+
+    PATH="''${PATH}":${pkgs.coreutils}/bin
+    PATH="''${PATH}":${pkgs.findutils}/bin
+    PATH="''${PATH}":${pkgs.jq}/bin/
+    PATH="''${PATH}":${pkgs.rsync}/bin/
+    PATH="''${PATH}":${pkgs.bash}/bin/
+    PATH="''${PATH}":${pkgs.curl}/bin/
+    PATH="''${PATH}":${pkgs.moreutils}/bin/
+    PATH="''${PATH}":${pkgs.gnutar}/bin
+    PATH="''${PATH}":${pkgs.gzip}/bin/
+    PATH="''${PATH}":${pkgs.procps}/bin/
+    PATH="''${PATH}":${pkgs.exa}/bin/
+    PATH="''${PATH}":${pkgs.git}/bin/
+    PATH="''${PATH}":${pkgs.gnugrep}/bin/
+    PATH="''${PATH}":${
+      inputs.version.defaultPackage."${builtins.currentSystem}"
+    }/bin/
+
+    export PATH
+
+    task test
+
+  '';
+
+  # This scritp is used to deploy the app to the gitlab registry
+  # It is used by the gitlab-ci.yml file
+  # The environment variables are set in the gitlab project settings
+  scripts.deploy-lib.exec = ''
+    #!${pkgs.bash}/bin/bash
+
+    PATH="''${PATH}":${pkgs.coreutils}/bin
+    PATH="''${PATH}":${pkgs.jq}/bin/
+    PATH="''${PATH}":${pkgs.curl}/bin/
+    PATH="''${PATH}":${pkgs.moreutils}/bin/
+    PATH="''${PATH}":${pkgs.gnutar}/bin
+    PATH="''${PATH}":${pkgs.gzip}/bin/
+    PATH="''${PATH}":${pkgs.exa}/bin/
+    PATH="''${PATH}":${pkgs.git}/bin/
+    PATH="''${PATH}":${
+      inputs.version.defaultPackage."${builtins.currentSystem}"
+    }/bin/
+
+    export PATH
+
+    if [[ -f .env-gitlab-ci ]]; then
+        source .env-gitlab-ci
+        rm .env-gitlab-ci
+    fi
+
+    set -x
+    ## if $HOME not set, set it to current directory
+    if [[ -z "''${HOME}" ]]; then
+        HOME=$(pwd)
+    fi
+
+    export HOME
+
+    git config user.email "''${GITLAB_USER_EMAIL}"
+    git config user.name "''${GITLAB_USER_NAME:-"Gitlab CI"}"
+    git config pull.rebase true
+    git config http.sslVerify "false"
+    git remote set-url origin https://pad:''${GITLAB_TOKEN}@''${CI_REPOSITORY_URL#*@}
+
+    git fetch --all --tags --unshallow
+    git reset --hard origin/master
+    git checkout $CI_COMMIT_REF_NAME
+    git pull origin $CI_COMMIT_REF_NAME
+
+    if [ ! -z "''${CI_PROJECT_DIR}" ]; then
+        echo "CI_PROJECT_DIR is set, using it as project root."
+        project_root=$(realpath "''${CI_PROJECT_DIR}")/
+    elif [ ! -z "''${DEVENV_ROOT}" ]; then
+        echo "DEVENV_ROOT is set, using it as project root."
+        project_root=$(realpath "''${DEVENV_ROOT}")/
+    else
+        echo "Error: DEVENV_ROOT or CI_PROJECT_DIR environment variables are not set."
+        exit 1  
+    fi
+
+    if [ ! -d "''${project_root}" ]; then
+        echo "Error: Project root directory does not seem to be valid."
+        echo "Check the DEVENV_ROOT or CI_PROJECT_DIR environment variables."
+        exit 1
+    fi
+
+    if [ -z "'CI_JOB_TOKEN" ]; then
+        echo "Error: CI_JOB_TOKEN variable is not set."
+        exit 1
+    fi
+
+    git --no-pager log --decorate=short --pretty=oneline
+    gitVersion=v$(version predict)
+    git tag -a $gitVersion -m"chore: bump version" 
+    git --no-pager log --decorate=short --pretty=oneline
+    git push -o ci.skip origin ''${CI_COMMIT_REF_NAME} --tags
+
+    echo "done"
+
+  '';
+
+  enterShell = ''
+        
+    cat <<'EOF' > Taskfile.yml
+
+    # THIS FILE IS AUTOGENERATED BY THE DEVENVSHELL
+    # DO NOT EDIT THIS FILE MANUALLY
+    # INSTEAD EDIT THE DEVENVSHELL CONFIGURATION FILE devenv.nix 
+    # AND OPEN A SHELL WITH THE COMMAND devenv shell
+    #
+    # Information about the task runner can be found here:
+    # https://taskfile.dev
+
+    version: '3'
+
+    tasks:
+      default:
+        cmds:
+          - task --list
+        silent: true
+        
+      test:
+        desc: Execute unit tests in Go.
+        cmds:
+          - echo "Execute unit tests in Go."
+          - go test -cover -v ./...
+          - go test -bench -v ./...
+          - go test -race -v ./...
+
+      test-fuzz:
+        desc: Conduct fuzzing tests.#
+        cmds:  
+          - echo "Conduct fuzzing tests."
+          - go test -v -fuzztime=30s -fuzz=Fuzz ./...
+
+      add-licenses:
+        desc: Attach license headers to Go files.
+        cmds:
+          - echo "Attach license headers to Go files."
+          - go install github.com/google/addlicense@latest
+          - addlicense -c "schukai GmbH" -s -l "AGPL-3.0" ./*.go
+        silent: true
+        
+      check-licenses:
+        desc: Check license headers of Go files.
+        silent: true
+        cmds:
+          - go-licenses save "$(get-go-default-packages)"  --ignore "gitlab.schukai.com"  --force --save_path ''${DEVENV_ROOT}/licenses/
+
+      check:
+        desc: Confirm repository status.
+        cmds:
+          - git diff-index --quiet HEAD || (echo "There are uncommitted changes after running make. Please commit or stash them before running make."; exit 1)
+        silent: true
+
+      commit:
+        desc: Commit changes to the repository.
+        aliases:
+          - c
+          - ci
+          - git-commit
+        cmds:
+          - do-git-commit
+    EOF
+
+    cat <<'EOF' > .gitlab-ci.yml
+
+    # THIS FILE IS AUTOGENERATED BY THE DEVENVSHELL
+    # DO NOT EDIT THIS FILE MANUALLY
+    # INSTEAD EDIT THE DEVENVSHELL CONFIGURATION FILE devenv.nix
+    # AND OPEN A SHELL WITH THE COMMAND devenv shell
+    #
+
+    image: docker-registry.schukai.com:443/nixos-ci-devenv:latest
+
+    services:
+      - docker:dind
+
+    variables:
+      # The repo name as used in
+      # https://github.com/nix-community/NUR/blob/master/repos.json
+      NIXOS_VERSION: "23.05"
+      NIXPKGS_ALLOW_UNFREE: "1"
+      NIXPKGS_ALLOW_INSECURE: "1"
+      DOCKER_DRIVER: overlay2
+      GIT_DEPTH: 10
+
+    stages:
+      - test
+      - deploy 
+
+    before_script:
+      - nix shell nixpkgs#coreutils-full -c mkdir -p /certs/client/
+      - nix shell nixpkgs#coreutils-full -c ln -fs /etc/ssl/certs/ca-bundle.crt /certs/client/ca.pem
+      - echo > .env-gitlab-ci
+      - variables=("HOME=$HOME" "CI_COMMIT_REF_NAME=$CI_COMMIT_REF_NAME" "CI_REPOSITORY_URL=$CI_REPOSITORY_URL" "GITLAB_TOKEN=$GITLAB_TOKEN" "CI_JOB_TOKEN=$CI_JOB_TOKEN" "GITLAB_USER_EMAIL=$GITLAB_USER_EMAIL" "GITLAB_USER_NAME=\"$GITLAB_USER_NAME\"" "CI_REGISTRY_USER=$CI_REGISTRY_USER" "CI_PROJECT_ID=$CI_PROJECT_ID" "CI_PROJECT_DIR=$CI_PROJECT_DIR" "CI_API_V4_URL=$CI_API_V4_URL" "CI_PROJECT_NAME=$CI_PROJECT_NAME" "CI_COMMIT_SHORT_SHA=$CI_COMMIT_SHORT_SHA"); for var in "''${variables[@]}"; do echo "$var" >> .env-gitlab-ci; done
+      - cat .env-gitlab-ci
+
+    after_script:
+      - if [ -f .env-gitlab-ci ]; then rm .env-gitlab-ci; fi
+
+    test:
+      stage: test
+      tags:
+        - nixos
+      script:
+        - devenv shell test-lib
+
+      cache:
+        - key: nixos
+          paths:
+            - /nix/store
+      
+      artifacts:
+        paths:
+          - dist
+
+    deploy:
+      stage: deploy
+      tags:
+        - nixos
+      script:
+        - devenv shell -c deploy-lib
+
+      when: on_success
+
+      cache:
+        - key: nixos
+          paths:
+            - /nix/store
+
+
+      artifacts:
+        paths:
+          - dist   
+    EOF
+
+       
+        
+  '';
+
+  scripts.do-git-commit.exec = ''
+    #!/usr/bin/env bash
+
+    # Define colors if the terminal supports it
+    if [ -t 1 ]; then
+      RED='\033[0;31m'
+      GREEN='\033[0;32m'
+      RESET='\033[0m'
+      BOLD='\033[1m'
+    else
+      RED=""
+      GREEN=""
+      RESET=""
+    fi
+
+    step=1
+
+    reset
+    clear
+
+    # create random log file
+    LOGFILE="$(mktemp)"
+    if [ $? -ne 0 ]; then
+      echo -e "''${RED}✖ Could not create temporary log file. Exiting.''${RESET}"
+      exit 1
+    fi
+
+    log_and_display() {
+      echo -e "''${GREEN}==> $step. $1''${RESET}" | tee -a $LOGFILE
+      step=$((step + 1))
+    }
+
+    log_error_and_display() {
+      echo -e "''${RED}==> $step. $1''${RESET}" | tee -a $LOGFILE
+    }
+
+    printLogfileAndExit() {
+      exit_code=$1
+      echo -e "\n\n========================================\n\n\n"
+
+      echo -e "\n\n''${BOLD}Git and GitLab Automation Script''${RESET}\n\nI have performed the following actions:\n\n"
+      cat "$LOGFILE"
+
+      # Optional: Remove log file
+      rm -f "$LOGFILE"
+
+      if [ $exit_code -eq 0 ]; then
+        echo -e "\n''${GREEN}✔''${RESET} All actions were successful" | tee -a $LOGFILE
+      elif [ $exit_code -eq -1 ]; then
+        echo -e "\n''${RED}✖''${RESET} The script was manually cancelled" | tee -a $LOGFILE
+        exit_code=0
+      else
+        echo -e "\n''${RED}✖''${RESET} Some actions failed" | tee -a $LOGFILE
+      fi
+
+      exit $exit_code
+    }
+
+    print_headline() {
+      local title=$1
+      local underline=$(printf '─%.0s' $(seq 1 ''${#title}))
+      echo -e "\n\n''${BOLD}''${title}\n''${underline}''${RESET}\n"
+    }
+
+    do_cancel() {
+      echo -e "''${RED}==> ✖ Cancelled.''${RESET}" | tee -a $LOGFILE
+      printLogfileAndExit -1
+    }
+
+    # Function for unified logging and display
+    log_action() {
+      if [ $? -eq 0 ]; then
+        echo -e "    ''${GREEN}✔''${RESET} $1: Successful" | tee -a $LOGFILE
+      else
+        echo -e "    ''${RED}✖''${RESET} $1: Failed" | tee -a $LOGFILE
+        printLogfileAndExit 1
+      fi
+    }
+
+    print_what_to_do() {
+      echo -e "\n\nWhat do you want to do?\n"
+    }
+
+    git_status=$(git status --porcelain)
+    if [[ -z "$git_status" ]]; then
+      log_error_and_display "No changes to commit. Exiting."
+      printLogfileAndExit 0
+    fi
+
+    print_headline "Choose commit type"
+    selection=$(gum choose "feat: (new feature for the user, not a new feature for build script)" "fix: (bug fix for the user, not a fix to a build script)" "chore: (updating grunt tasks etc.; no production code change)" "docs: (changes to the documentation)" "style: (formatting, missing semi colons, etc; no production code change)" "refactor: (refactoring production code, eg. renaming a variable)" "test: (adding missing tests, refactoring tests; no production code change)" "Cancel")
+
+    commit_type=$(echo "$selection" | awk -F':' '{print $1}')
+
+    if [[ "$commit_type" == "Cancel" ]]; then
+      do_cancel
+    fi
+
+    log_and_display "You chose the commit type: $commit_type"
+
+    # NEXT STEP ISSUE HANDLING ############################################################################################################
+    #log_and_display "Issue handling"
+
+    gitlabIssues=()
+    while IFS= read -r line; do
+      if [[ $line =~ ^# ]]; then
+        id=$(echo "$line" | awk '{print substr($1, 2)}')
+        title=$(echo "$line" | awk -F'about' '{print $1}' | awk '{$1=$2=""; print substr($0, 3)}')
+        gitlabIssues+=("$id > $title")
+      fi
+    done < <(gum spin --spinner dot --show-output --title "Ask gitlab ..." -- glab issue list --output-format=details)
+
+    ## if issues are available, ask if user wants to use an existing issue or create a new one
+    createOption="Create new issue"
+    existingOption="Use existing issue"
+    cancelOption="Cancel"
+
+    print_headline "Choose issue handling"
+    if [ ''${#gitlabIssues[@]} -eq 0 ]; then
+      log_and_display "There are no issues available."
+
+      print_what_to_do
+      choice=$(gum choose "$createOption" "$cancelOption")
+
+    else
+      log_and_display "There are ''${#gitlabIssues[@]} issues available."
+      print_what_to_do
+      choice=$(gum choose "$createOption" "$existingOption" "$cancelOption")
+    fi
+
+    if [[ "$choice" == "$cancelOption" ]]; then
+      do_cancel
+    fi
+
+    ## array of issue ids
+    work_on_issue_ids=()
+
+    issue_text=""
+
+    if [[ "$choice" == "$createOption" ]]; then
+      print_headline "Create new issue"
+      issue_text=$(gum input --placeholder "Enter issue title")
+      echo -e "Enter issue description. ''${RED}End with Ctrl+D''${RESET}\n"
+      issue_description=$(gum write --placeholder "Enter issue description. End with Ctrl+D")
+      
+      if [[ -z "$issue_text" ]]; then
+        log_error_and_display "Issue title is empty. Exiting."
+        printLogfileAndExit 1
+      fi
+
+      log_and_display "You entered the issue title: $issue_text"
+      log_and_display "You entered the issue description: $issue_description"
+      echo -e "\n"
+
+      gum confirm "Do you want to create this issue?"
+      # gum confirm exits with status 0 if confirmed and status 1 if cancelled.
+      if [ $? -eq 1 ]; then
+        do_cancel
+      fi
+
+      issue_output=$(glab issue create -t"$issue_text" --no-editor --description "$issue_description")
+      issue_id=$(echo "$issue_output" | grep -oP '(?<=/issues/)\d+')
+
+      work_on_issue_ids+=("$issue_id")
+
+      log_action "glab issue with id $issue_id created"
+
+    else
+
+      print_headline "Use existing issue"
+      echo -e "Select issue with arrow keys and press tab or space to select. Press enter to confirm.\n"
+      issue_ids=$(gum choose --no-limit "''${gitlabIssues[@]}")
+
+      # assign issue_ids to work_on_issue_ids. iterate over lines and take integer from beginning of line
+      while IFS= read -r line; do
+        work_on_issue_ids+=($(echo "$line" | grep -oP '^\d+'))
+      done <<<"$issue_ids"
+
+    fi
+
+    if [ ''${#work_on_issue_ids[@]} -eq 0 ]; then
+      log_and_display "No issue selected. Exiting."
+      printLogfileAndExit 0
+    fi 
+
+    # NEXT STEP COMMIT MESSAGE ############################################################################################################
+    # print work_on_issue_ids
+    work_on_issue_ids_string=""
+    for i in "''${work_on_issue_ids[@]}"; do
+      work_on_issue_ids_string+="#$i "
+    done
+
+    log_and_display "You chose to work on the following issues: ''${work_on_issue_ids_string}"
+
+
+    print_headline "Check for changes to commit"
+
+    # ' ' = unmodified
+    # M = modified
+    # T = file type changed (regular file, symbolic link or submodule)
+    # A = added
+    # D = deleted
+    # R = renamed
+    # C = copied (if config option status.renames is set to "copies")
+    # U = updated but unmerged
+    # https://man.freebsd.org/cgi/man.cgi?query=git-status&sektion=1&manpath=freebsd-release-ports
+
+    count_all_changes=$(echo "$git_status" | wc -l)
+    count_staged_changes=$(echo "$git_status" | grep -c '^M')
+    count_new_staged_files=$(echo "$git_status" | grep -c '^A')
+    count_staged_changes=$((count_staged_changes + count_new_staged_files))
+
+
+
+    git_options_all="All $count_all_changes changes"
+    git_options_staged="Only the $count_staged_changes staged changes"
+    git_options_select_files="Select files"
+    git_options_cancel="Cancel"
+
+    git_options_array=()
+    if [[ $count_all_changes -gt 0 ]]; then
+      git_options_array+=("$git_options_all")
+    fi
+
+    if [[ $count_staged_changes -gt 0 ]]; then
+      git_options_array+=("$git_options_staged")
+    fi
+
+    git_options_array+=( "$git_options_select_files" )
+    git_options_array+=( "$git_options_cancel" )
+
+
+    selection=$(gum choose "''${git_options_array[@]}")
+    if [[ "$selection" == "$git_options_cancel" ]]; then
+      do_cancel
+    fi
+
+    if [[ "$selection" == "$git_options_all" ]]; then
+      git add -A
+      echo "1"
+    elif [[ "$selection" == "$git_options_select_files" ]]; then
+
+      files=()
+      while IFS= read -r line; do
+        files+=("$line")
+      done <<<"$git_status"
+        
+      selected_files=$(gum choose --no-limit "''${files[@]}")
+      
+      # no files selected
+      if [[ -z "$selected_files" ]]; then
+        log_and_display "No files selected. Exiting."
+        printLogfileAndExit 0
+      fi
+
+      # add selected files
+      while IFS= read -r line; do
+        ## git proclimne could have letter, ? or ! at the beginning of the line
+        file=$(echo "$line" | awk '{print $2}')
+        if [[ -z "$file" || ! -f "$file" ]]; then
+          log_and_display "No file found in line: $line"
+          continue
+        fi
+        
+        git add "$file"
+      done <<<"$selected_files"
+      
+    fi
+
+    ## count staged changes again and print
+    count_staged_changes=$(echo "$git_status" | grep -c '^M')
+    count_new_staged_files=$(echo "$git_status" | grep -c '^A')
+    count_staged_changes=$((count_staged_changes + count_new_staged_files))
+
+    log_and_display "You have $count_staged_changes staged changes to commit."
+
+    # NEXT STEP COMMIT MESSAGE ############################################################################################################
+
+    print_headline "Enter commit message"
+    commit_message=$(gum input --placeholder "Enter commit message" --value "$commit_type: $issue_text $work_on_issue_ids_string")
+
+    if [[ -z "$commit_message" ]]; then
+      log_error_and_display "Commit message is empty. Exiting."
+      printLogfileAndExit 1
+    fi
+
+    log_and_display "You entered the commit message: $commit_message"
+
+    gum confirm "Do you want to commit with this message?"
+    if [ $? -eq 1 ]; then
+      do_cancel
+    fi
+
+    # NEXT STEP COMMIT ####################################################################################################################
+    print_headline "Committing changes"
+
+    if ! git commit -m "$commit_message" ; then
+      log_error_and_display "Commit failed. Exiting."
+      printLogfileAndExit 1
+    fi
+
+    log_and_display "Commit successful."
+
+    # NEXT STEP PUSH ######################################################################################################################
+
+    print_headline "Pushing changes"
+
+    if ! git push ; then
+      log_error_and_display "Push failed. Exiting."
+      printLogfileAndExit 1
+    fi
+
+    log_and_display "Push successful."
+
+    # Close issue ######################################################################################################################
+
+    print_headline "Closing issues"
+
+    for issue_id in "''${work_on_issue_ids[@]}"; do
+      
+      gum confirm "Do you want to close issue #$issue_id?"
+      if [ $? -eq 1 ]; then
+        continue
+      fi
+      
+      if ! glab issue close "$issue_id" ; then
+        log_error_and_display "Closing issue $issue_id failed. Exiting."
+      else
+        log_and_display "Closing issue $issue_id successful."  
+      fi
+    done
+
+    printLogfileAndExit 0
+  '';
+
+}

devenv.yaml

+inputs:
+  nixpkgs:
+    url: github:nixos/nixpkgs/nixos-23.05
+
+  version:
+    url: git+https://gitlab.schukai.com/oss/utilities/version.git
+    flake: true

error.go

+package jobqueue
+
+import "fmt"
+
+var (
+	ErrCPUPercentage         = fmt.Errorf("could not get CPU percentage")
+	ErrIntervalIsZero        = fmt.Errorf("interval must not be 0")
+	ErrResourceLimitExceeded = fmt.Errorf("resource limit exceeded")
+	ErrNoRunDefined          = fmt.Errorf("no runnable function defined")
+	ErrCycleDetected         = fmt.Errorf("cycle detected")
+	ErrJobAlreadyExists      = fmt.Errorf("job already exists")
+	ErrUnknownDependency     = fmt.Errorf("unknown dependency")
+	ErrMissingDependency     = fmt.Errorf("missing dependency")
+	ErrJobNotFound           = fmt.Errorf("job not found")
+	ErrJobIsDependency       = fmt.Errorf("job is a dependency")
+	ErrNotRunning            = fmt.Errorf("job queue is not running")
+	ErrAlreadyPaused         = fmt.Errorf("job queue is already paused")
+	ErrAlreadyStopped        = fmt.Errorf("job queue is already stopped")
+	ErrNotPaused             = fmt.Errorf("job queue is not paused")
+	ErrAlreadyStarted        = fmt.Errorf("job queue is already started")
+	ErrTimeout               = fmt.Errorf("job timed out")
+	//ErrInitializationFailed  = fmt.Errorf("resource monitoring initialization failed")
+)

executor.go

+package jobqueue
+
+import (
+	"context"
+	"sync"
+	"sync/atomic"
+	"time"
+)
+
+const (
+	MODE_STOPPED = iota
+	MODE_RUNNING
+	MODE_PAUSED
+)
+
+type mode int32
+
+type shouldStopFunc func(executor *jobExecutor) bool
+
+type jobExecutor struct {
+	mutex sync.Mutex
+
+	Queue        JobsInterface
+	Ctx          context.Context
+	CancelFunc   context.CancelFunc
+	MaxParallel  int
+	interval     time.Duration
+	Ticker       *time.Ticker
+	cleanupTimer *time.Ticker
+	//stopChan     chan struct{}
+	sem chan struct{}
+
+	pauseChan  chan struct{}
+	resumeChan chan struct{}
+
+	runningMode int32
+
+	doneChan chan struct{}
+
+	shouldStop shouldStopFunc
+}
+
+func NewJobExecutor(queue JobsInterface, maxParallel int, interval time.Duration, shouldStopFunc shouldStopFunc) *jobExecutor {
+
+	execCtx, cancelFunc := context.WithCancel(context.Background())
+
+	return &jobExecutor{
+		Queue:        queue,
+		Ctx:          execCtx,
+		CancelFunc:   cancelFunc,
+		MaxParallel:  maxParallel,
+		interval:     interval,
+		Ticker:       nil,
+		cleanupTimer: nil,
+		//stopChan:     make(chan struct{}),
+		sem: make(chan struct{}, maxParallel),
+
+		pauseChan:   make(chan struct{}),
+		resumeChan:  make(chan struct{}),
+		runningMode: MODE_STOPPED,
+		shouldStop:  shouldStopFunc,
+	}
+}
+
+func (je *jobExecutor) executeJobs() {
+
+	je.mutex.Lock()
+	je.Ticker = time.NewTicker(je.interval)
+	je.cleanupTimer = time.NewTicker(10 * je.interval)
+	je.setRunningFlag(MODE_RUNNING)
+	je.mutex.Unlock()
+
+	for {
+		select {
+		case <-je.Ticker.C:
+
+			if !je.IsPaused() {
+				je.runJobs()
+				if je.shouldStop != nil && je.shouldStop(je) {
+					_ = je.Stop()
+					return
+				}
+			}
+
+		case <-je.cleanupTimer.C:
+			je.Queue.Cleanup()
+		case <-je.pauseChan:
+			je.setRunningFlag(MODE_PAUSED)
+		case <-je.resumeChan:
+			je.setRunningFlag(MODE_RUNNING)
+		case <-je.Ctx.Done():
+
+			je.mutex.Lock()
+			je.Ticker.Stop()
+			je.cleanupTimer.Stop()
+			je.setRunningFlag(MODE_STOPPED)
+			je.mutex.Unlock()
+
+			return
+		}
+	}
+
+}
+
+func (je *jobExecutor) runJobs() {
+	// Get jobs that can be executed
+	jobs := je.Queue.GetExecutableJobs()
+	if len(jobs) == 0 {
+		return
+	}
+
+	var wg sync.WaitGroup
+
+	// Map to track the status of executed jobs
+	jobStatus := make(map[JobIDType]bool)
+	for _, job := range jobs {
+		jobStatus[job.GetId()] = false
+	}
+
+	// Channel for coordinating job execution
+	jobChan := make(chan ReadOnlyJob)
+
+	// Determine the number of jobs to be sent to the channel
+	for _, job := range jobs {
+		dependencies := job.GetDependencies()
+		canRun := true
+		for _, dependencyID := range dependencies {
+			// Check if dependencies have already been executed
+			if !jobStatus[dependencyID] {
+				canRun = false
+				break
+			}
+		}
+
+		if canRun {
+			wg.Add(1) // Increment the WaitGroup counter for each job to be sent
+		}
+	}
+
+	// Loop through all jobs and execute only if dependencies are met
+	go func() {
+		for _, job := range jobs {
+			dependencies := job.GetDependencies()
+			canRun := true
+			for _, dependencyID := range dependencies {
+				// Check if dependencies have already been executed
+				if !jobStatus[dependencyID] {
+					canRun = false
+					break
+				}
+			}
+
+			if canRun {
+				// Send the job to the job channel
+				jobChan <- job
+			}
+		}
+		close(jobChan) // Close the channel after all jobs have been sent
+	}()
+
+	maxParallel := je.MaxParallel
+	if len(jobs) < maxParallel {
+		maxParallel = len(jobs)
+	}
+
+	// Execute jobs in parallel
+	for i := 0; i < maxParallel; i++ {
+		go func() {
+			for job := range jobChan {
+				job.Run(je.Ctx)
+				// Mark the job as executed
+				jobStatus[job.GetId()] = true
+				wg.Done()
+			}
+		}()
+	}
+
+	// Wait for all jobs to complete before returning
+	wg.Wait()
+}
+
+func (je *jobExecutor) Start() error {
+
+	if je.IsRunning() {
+		return ErrAlreadyStarted
+	}
+
+	if je.IsPaused() {
+		return je.Resume()
+	}
+
+	go je.executeJobs()
+	return nil
+}
+
+func (je *jobExecutor) Stop() error {
+
+	if !je.IsRunning() && !je.IsPaused() {
+		return ErrAlreadyStopped
+	}
+
+	je.CancelFunc()
+	return nil
+}
+
+func (je *jobExecutor) Pause() error {
+
+	if je.IsPaused() {
+		return ErrAlreadyPaused
+	}
+
+	je.mutex.Lock()
+	je.pauseChan <- struct{}{}
+	je.setRunningFlag(MODE_PAUSED)
+	je.mutex.Unlock()
+
+	return nil
+
+}
+
+func (je *jobExecutor) Resume() error {
+
+	if !je.IsPaused() {
+		return ErrNotPaused
+	}
+
+	je.mutex.Lock()
+	je.resumeChan <- struct{}{}
+	je.setRunningFlag(MODE_RUNNING)
+	je.mutex.Unlock()
+
+	return nil
+
+}
+
+func (je *jobExecutor) IsPaused() bool {
+	return atomic.LoadInt32(&je.runningMode) == MODE_PAUSED
+}
+
+func (je *jobExecutor) IsRunning() bool {
+	return atomic.LoadInt32(&je.runningMode) == MODE_RUNNING
+}
+
+func (je *jobExecutor) setRunningFlag(mode int32) {
+	atomic.StoreInt32(&je.runningMode, mode)
+}

executor_test.go

+package jobqueue
+
+import (
+	"context"
+	"testing"
+	"time"
+)
+
+type TestRunnable struct{}
+
+func (r TestRunnable) Run(ctx context.Context) (int, any, error) {
+	// Dummy run implementation
+	return 0, nil, nil
+}
+
+func TestJobExecutorStartAndStop(t *testing.T) {
+	queue := NewJobs()
+	executor := NewJobExecutor(queue, 1, time.Millisecond*50, nil)
+
+	// Fügen Sie einen Job zur Warteschlange hinzu
+	err := queue.AddJob(JobSpecification{
+		Id:          "test-job",
+		Priority:    1,
+		Concurrency: 1,
+	}, TestRunnable{})
+
+	if err != nil {
+		t.Fatalf("Failed to add job: %v", err)
+	}
+
+	err = executor.Start()
+	if err != nil {
+		t.Errorf("Failed to start executor: %v", err)
+	}
+
+	for i := 0; i < 10; i++ {
+		time.Sleep(time.Millisecond * 100)
+		if executor.IsRunning() {
+			break
+		}
+	}
+
+	if !executor.IsRunning() {
+		t.Errorf("Executor should be running")
+	}
+
+	err = executor.Stop()
+	for i := 0; i < 10; i++ {
+		time.Sleep(time.Millisecond * 100)
+		if !executor.IsRunning() {
+			break
+		}
+	}
+
+	if err != nil {
+		t.Errorf("Failed to stop executor: %v", err)
+	}
+
+	if executor.IsRunning() {
+		t.Errorf("Executor should not be running")
+	}
+}
+
+func TestJobExecutorPauseAndResume(t *testing.T) {
+	queue := NewJobs()
+	executor := NewJobExecutor(queue, 1, time.Millisecond*50, nil)
+
+	// Fügen Sie einen Job zur Warteschlange hinzu
+	err := queue.AddJob(JobSpecification{
+		Id:          "test-job",
+		Priority:    1,
+		Concurrency: 1,
+	}, TestRunnable{})
+	if err != nil {
+		t.Fatalf("Failed to add job: %v", err)
+	}
+
+	err = executor.Start()
+	if err != nil {
+		t.Errorf("Failed to start executor: %v", err)
+	}
+
+	for i := 0; i < 10; i++ {
+		time.Sleep(time.Millisecond * 100)
+		if executor.IsRunning() {
+			break
+		}
+	}
+
+	err = executor.Pause()
+	if err != nil {
+		t.Errorf("Failed to pause executor: %v", err)
+	}
+
+	for i := 0; i < 10; i++ {
+		time.Sleep(time.Millisecond * 100)
+		if executor.IsPaused() {
+			break
+		}
+	}
+
+	if !executor.IsPaused() {
+		t.Errorf("Executor should be paused")
+	}
+
+	err = executor.Resume()
+	if err != nil {
+		t.Errorf("Failed to resume executor: %v", err)
+	}
+
+	for i := 0; i < 10; i++ {
+		time.Sleep(time.Millisecond * 100)
+		if executor.IsRunning() {
+			break
+		}
+	}
+
+	if executor.IsPaused() {
+		t.Errorf("Executor should not be paused")
+	}
+
+	err = executor.Stop()
+	if err != nil {
+		t.Errorf("Failed to stop executor: %v", err)
+	}
+
+	for i := 0; i < 10; i++ {
+		time.Sleep(time.Millisecond * 100)
+		if !executor.IsRunning() {
+			break
+		}
+	}
+
+	if executor.IsRunning() {
+		t.Errorf("Executor should not be running")
+	}
+}