woodpecker-helm3/internal/helm/plan.go
Erin Call 13c663e906
Initialize kubernetes config on upgrade
This change revealed more about how the system needs to work, so there
are some supporting changes:

* helm.upgrade and helm.help are now vars rather than raw functions.
    This allows unit tests to target the "which step should we run"
    logic directly by comparing function pointers, rather than having to
    configure/prepare a fully-valid Plan and then infer the logic’s
    correctness based on the Plan’s state.
* configuration that's specific to kubeconfig initialization is now part
    of the InitKube struct rather than run.Config, since other steps
    shouldn’t need access to those settings (particularly the secrets).
* Step.Execute now receives a run.Config so it can log debug output.
2019-12-16 15:41:04 -08:00

122 lines
2.6 KiB
Go

package helm
import (
"fmt"
"github.com/pelotech/drone-helm3/internal/run"
"os"
)
const kubeConfigTemplate = "/root/.kube/config.tpl"
// A Step is one step in the plan.
type Step interface {
Prepare(run.Config) error
Execute(run.Config) error
}
// A Plan is a series of steps to perform.
type Plan struct {
steps []Step
cfg Config
runCfg run.Config
}
// NewPlan makes a plan for running a helm operation.
func NewPlan(cfg Config) (*Plan, error) {
p := Plan{
cfg: cfg,
runCfg: run.Config{
Debug: cfg.Debug,
KubeConfig: cfg.KubeConfig,
Values: cfg.Values,
StringValues: cfg.StringValues,
ValuesFiles: cfg.ValuesFiles,
Namespace: cfg.Namespace,
Stdout: os.Stdout,
Stderr: os.Stderr,
},
}
p.steps = (*determineSteps(cfg))(cfg)
for i, step := range p.steps {
if cfg.Debug {
fmt.Fprintf(os.Stderr, "calling %T.Prepare (step %d)\n", step, i)
}
if err := step.Prepare(p.runCfg); err != nil {
err = fmt.Errorf("while preparing %T step: %w", step, err)
return nil, err
}
}
return &p, nil
}
// determineSteps is primarily for the tests' convenience: it allows testing the "which stuff should
// we do" logic without building a config that meets all the steps' requirements.
func determineSteps(cfg Config) *func(Config) []Step {
switch cfg.Command {
case "upgrade":
return &upgrade
case "delete":
panic("not implemented")
case "lint":
panic("not implemented")
case "help":
return &help
default:
switch cfg.DroneEvent {
case "push", "tag", "deployment", "pull_request", "promote", "rollback":
return &upgrade
default:
panic("not implemented")
}
}
}
// Execute runs each step in the plan, aborting and reporting on error
func (p *Plan) Execute() error {
for i, step := range p.steps {
if p.cfg.Debug {
fmt.Fprintf(os.Stderr, "calling %T.Execute (step %d)\n", step, i)
}
if err := step.Execute(p.runCfg); err != nil {
return fmt.Errorf("in execution step %d: %w", i, err)
}
}
return nil
}
var upgrade = func(cfg Config) []Step {
steps := make([]Step, 0)
steps = append(steps, &run.InitKube{
SkipTLSVerify: cfg.SkipTLSVerify,
Certificate: cfg.Certificate,
APIServer: cfg.APIServer,
ServiceAccount: cfg.ServiceAccount,
Token: cfg.KubeToken,
TemplateFile: kubeConfigTemplate,
})
steps = append(steps, &run.Upgrade{
Chart: cfg.Chart,
Release: cfg.Release,
ChartVersion: cfg.ChartVersion,
Wait: cfg.Wait,
ReuseValues: cfg.ReuseValues,
Timeout: cfg.Timeout,
Force: cfg.Force,
})
return steps
}
var help = func(cfg Config) []Step {
help := &run.Help{}
return []Step{help}
}