helmfile/pkg/app/two_pass_renderer.go

81 lines
2.8 KiB
Go

package app
import (
"bytes"
"fmt"
"github.com/roboll/helmfile/environment"
"github.com/roboll/helmfile/state"
"github.com/roboll/helmfile/tmpl"
"go.uber.org/zap"
"path/filepath"
"strings"
)
func prependLineNumbers(text string) string {
buf := bytes.NewBufferString("")
lines := strings.Split(text, "\n")
for i, line := range lines {
buf.WriteString(fmt.Sprintf("%2d: %s\n", i, line))
}
return buf.String()
}
type twoPassRenderer struct {
reader func(string) ([]byte, error)
env string
namespace string
filename string
logger *zap.SugaredLogger
abs func(string) (string, error)
}
func (r *twoPassRenderer) renderEnvironment(content []byte) environment.Environment {
firstPassEnv := environment.Environment{Name: r.env, Values: map[string]interface{}(nil)}
tmplData := state.EnvironmentTemplateData{Environment: firstPassEnv, Namespace: r.namespace}
firstPassRenderer := tmpl.NewFirstPassRenderer(filepath.Dir(r.filename), tmplData)
// parse as much as we can, tolerate errors, this is a preparse
yamlBuf, err := firstPassRenderer.RenderTemplateContentToBuffer(content)
if err != nil && r.logger != nil {
r.logger.Debugf("first-pass rendering input of \"%s\":\n%s", r.filename, prependLineNumbers(string(content)))
if yamlBuf == nil { // we have a template syntax error, let the second parse report
r.logger.Debugf("template syntax error: %v", err)
return firstPassEnv
}
}
c := state.NewCreator(r.logger, r.reader, r.abs)
c.Strict = false
// create preliminary state, as we may have an environment. Tolerate errors.
prestate, err := c.CreateFromYaml(yamlBuf.Bytes(), r.filename, r.env)
if err != nil && r.logger != nil {
switch err.(type) {
case *state.StateLoadError:
r.logger.Infof("could not deduce `environment:` block, configuring only .Environment.Name. error: %v", err)
}
r.logger.Debugf("error in first-pass rendering: result of \"%s\":\n%s", r.filename, prependLineNumbers(yamlBuf.String()))
}
if prestate != nil {
firstPassEnv = prestate.Env
}
return firstPassEnv
}
func (r *twoPassRenderer) renderTemplate(content []byte) (*bytes.Buffer, error) {
// try a first pass render. This will always succeed, but can produce a limited env
firstPassEnv := r.renderEnvironment(content)
tmplData := state.EnvironmentTemplateData{Environment: firstPassEnv, Namespace: r.namespace}
secondPassRenderer := tmpl.NewFileRenderer(r.reader, filepath.Dir(r.filename), tmplData)
yamlBuf, err := secondPassRenderer.RenderTemplateContentToBuffer(content)
if err != nil {
if r.logger != nil {
r.logger.Debugf("second-pass rendering failed, input of \"%s\":\n%s", r.filename, prependLineNumbers(string(content)))
}
return nil, err
}
if r.logger != nil {
r.logger.Debugf("second-pass rendering result of \"%s\":\n%s", r.filename, prependLineNumbers(yamlBuf.String()))
}
return yamlBuf, nil
}