// ProcessEvent reads, validates and emits a configuration.
func (b *configuratorBehavior) ProcessEvent(event cells.Event) error {
switch event.Topic() {
case ReadConfigurationTopic:
// Read configuration
filename, ok := event.Payload().GetString(ConfigurationFilenamePayload)
if !ok {
logger.Errorf("cannot read configuration without filename payload")
return nil
}
logger.Infof("reading configuration from %q", filename)
config, err := configuration.ReadFile(filename)
if err != nil {
return errors.Annotate(err, ErrCannotReadConfiguration, errorMessages)
}
// If wanted then validate it.
if b.validate != nil {
err = b.validate(config)
if err != nil {
return errors.Annotate(err, ErrCannotValidateConfiguration, errorMessages)
}
}
// All done, emit it.
pvs := cells.PayloadValues{
ConfigurationPayload: config,
}
b.ctx.EmitNew(ConfigurationTopic, pvs, event.Scene())
}
return nil
}
// TestReadFile tests reading a configuration out of a file.
func TestReadFile(t *testing.T) {
assert := audit.NewTestingAssertion(t, true)
tempDir := audit.NewTempDir(assert)
defer tempDir.Restore()
configFile, err := ioutil.TempFile(tempDir.String(), "configuration")
assert.Nil(err)
configFileName := configFile.Name()
_, err = configFile.WriteString("{config {foo 42}{bar 24}}")
assert.Nil(err)
configFile.Close()
config, err := configuration.ReadFile(configFileName)
assert.Nil(err)
v, err := config.At("foo").Value()
assert.Nil(err)
assert.Equal(v, "42")
v, err = config.At("bar").Value()
assert.Nil(err)
assert.Equal(v, "24")
_, err = configuration.ReadFile("some-not-existing-configuration-file-due-to-wierd-name")
assert.ErrorMatch(err, `.* cannot read configuration file .*`)
}