Kubernetes resources management tools

Table of Contents

• Installation
• How to use
• Configuration
  • Config file format
  • Environment variables substitution
  • Command line variables and variable files
  • Default variables
  • Sample configuration file
  • Configuration keys
• Resource groups
  • Resources dependency
  • Resource group configuration
  • Resource files glob
  • Waiting for pods or jobs

Installation

Check https://github.com/anduintransaction/rivendell/releases

How to use

• rivendell generate project.yml to generate a project file. See Configuration section for more detail about how to configure a project.
• Add your own kubernetes configuration files.
• Run rivendell up project.yml to create all resources.
• Run rivendell down project.ymlto destroy all resources.
• Run rivendell update project.yml to update all resources other than pod or job.
• Run rivendell upgrade project.yml to upgrade all resources, including pod and job. The pods and jobs must be stopped before upgrading

Configuration

Config file format

The configuration format is YAML

Environment variables substitution

Environment variables referenced with the $(...) notation within the configuration file will be replaced with the value of the environment variable, for instance:

namespace: $(KUBERNETES_NAMESPACE)

Command line variables and variable files

The configuration file also supports go-template:

namespace: {{.namespace}}

Variables can be passed to the configuration file by command line flags:

rivendell up project.yml --variable namespace=my-namespace

Or using variable file:

rivendell up project.yml --variableFile varFile

Sample varFile content:

namespace=my-namespace

If a variable key is specified more than once, the order of important is --variable > variable file > configuration file > default value

Default variables

• rivendellVarNamespace: Current kubernetes namespace
• rivendellVarContext: Current kubernetes context
• rivendellVarKubeConfig: Current kubernetes config file
• rivendellVarRootDir: Root directory of project

Sample configuration file

root_dir: .
namespace: coruscant
variables:
  postgresTag: {{.postgresImageTag}}
  redisTag: 4-alpine
  postgresSidecarImage: postgres-sidecar:{{.appTag}}
  redisSidecarImage: redis-sidecar:{{.appTag}}
resource_groups:
  - name: configs
    resources:
      - ./configs/*.yml
    excludes:
      - ./configs/*ignore*
  - name: secrets
    resources:
      - ./secrets/*.yml
  - name: databases
    resources:
      - ./databases/*.yml
    depend:
      - configs
      - secrets
  - name: init-jobs
    resources:
      - ./jobs/*.yml
    depend:
      - databases
  - name: services
    resources:
      - ./services/*.yml
    depend:
      - init-jobs
    wait:
      - name: init-postgres
        kind: job
      - name: init-redis
        kind: job
delete_namespace: true

Configuration keys

Key	Type	Description
root_dir	string	Root dir, relative to the configuration file. All kubernetes configuration files will be relative to this directory
namespace	string	Kubernetes namespace, value from command line flag will override this value
variables	map	Variables map, value from command line flags will override these values
resource_groups	array	See Resource groups
delete_namespace	string	Delete the namespace in down command or not

Resource groups

Resources dependency

Rivendell manages a graph of resource groups, with each group contains multiple resource files, and can depend on each others. If group A depends on group B, rivendell wait for all resources in group B to become ready before creating resources in group A. A resource is defined as ready when its kubernetes life cycle status is Active.

A resource group can also be configured to wait for some jobs or pods to complete.

Resource group configuration

Key	Type	Description
name	string	Name of the group
resources	string array	List of resource files. See Resource files glob
excludes	string array	List of excluded resources file
depend	string array	List of groups this group depends on
wait	array	See Waiting for pods or jobs

Resource files glob

A list of glob-based files can be add to resource group. Supported glob patterns are:

• path/to/*.yml matches all yml files under path/to
• path/*/*.yml matches all yml files under subfolder of path
• path/**/*.yml matches all yml files under any level of subfolder of path

Waiting for pods or jobs

A resource can be configured to wait for some pods or jobs to complete with:

wait:
  - name: job1
    kind: job
    timeout: 300
  - name: pod1
    kind: pod