pulumi/pkg/engine/eventsink.go
Matt Ellis 7587bcd7ec Have engine emit "events" instead of writing to streams
Previously, the engine would write to io.Writer's to display output.
When hosted in `pulumi` these writers were tied to os.Stdout and
os.Stderr, but other applications hosting the engine could send them
other places (e.g. a log to be sent to an another application later).

While much better than just using the ambient streams, this was still
not the best. It would be ideal if the engine could just emit strongly
typed events and whatever is hosting the engine could care about
displaying them.

As a first step down that road, we move to a model where operations on
the engine now take a `chan engine.Event` and during the course of the
operation, events are written to this channel. It is the
responsibility of the caller of the method to read from the channel
until it is closed (singifying that the operation is complete).

The events we do emit are still intermingle presentation with data,
which is unfortunate, but can be improved over time. Most of the
events today are just colorized in the client and printed to stdout or
stderr without much thought.
2017-10-09 18:24:56 -07:00

218 lines
5.8 KiB
Go

package engine
import (
"bytes"
"fmt"
"path/filepath"
"strconv"
"sync"
"github.com/pulumi/pulumi/pkg/diag"
"github.com/golang/glog"
"github.com/pulumi/pulumi/pkg/diag/colors"
"github.com/pulumi/pulumi/pkg/util/contract"
)
func newEventSink(events chan Event, opts diag.FormatOptions) diag.Sink {
contract.Require(events != nil, "events")
return &eventSink{
events: events,
opts: opts,
counts: make(map[diag.Severity]int),
}
}
const eventSinkIDPrefix = "PU"
// eventSink is a sink which writes all events to a channel
type eventSink struct {
events chan Event // the channel to emit events into.
opts diag.FormatOptions // a set of options that control output style and content.
counts map[diag.Severity]int // the number of messages that have been issued per severity.
mutex sync.RWMutex // a mutex for guarding updates to the counts map
}
func (s *eventSink) Count() int { return s.Debugs() + s.Infos() + s.Errors() + s.Warnings() }
func (s *eventSink) Debugs() int { return s.getCount(diag.Debug) }
func (s *eventSink) Infos() int { return s.getCount(diag.Info) }
func (s *eventSink) Infoerrs() int { return s.getCount(diag.Infoerr) }
func (s *eventSink) Errors() int { return s.getCount(diag.Error) }
func (s *eventSink) Warnings() int { return s.getCount(diag.Warning) }
func (s *eventSink) Success() bool { return s.Errors() == 0 }
func (s *eventSink) Logf(sev diag.Severity, d *diag.Diag, args ...interface{}) {
switch sev {
case diag.Debug:
s.Debugf(d, args...)
case diag.Info:
s.Infof(d, args...)
case diag.Infoerr:
s.Infoerrf(d, args...)
case diag.Warning:
s.Warningf(d, args...)
case diag.Error:
s.Errorf(d, args...)
default:
contract.Failf("Unrecognized severity: %v", sev)
}
}
func (s *eventSink) Debugf(d *diag.Diag, args ...interface{}) {
// For debug messages, write both to the glogger and a stream, if there is one.
glog.V(3).Infof(d.Message, args...)
msg := s.Stringify(diag.Debug, d, args...)
if glog.V(9) {
glog.V(9).Infof("eventSink::Debug(%v)", msg[:len(msg)-1])
}
s.events <- diagDebugEvent(s.opts.Colors, msg)
s.incrementCount(diag.Debug)
}
func (s *eventSink) Infof(d *diag.Diag, args ...interface{}) {
msg := s.Stringify(diag.Info, d, args...)
if glog.V(5) {
glog.V(5).Infof("eventSink::Info(%v)", msg[:len(msg)-1])
}
s.events <- diagInfoEvent(s.opts.Colors, msg)
s.incrementCount(diag.Info)
}
func (s *eventSink) Infoerrf(d *diag.Diag, args ...interface{}) {
msg := s.Stringify(diag.Info /* not Infoerr, just "info: "*/, d, args...)
if glog.V(5) {
glog.V(5).Infof("eventSink::Infoerr(%v)", msg[:len(msg)-1])
}
s.events <- diagInfoerrEvent(s.opts.Colors, msg)
s.incrementCount(diag.Infoerr)
}
func (s *eventSink) Errorf(d *diag.Diag, args ...interface{}) {
msg := s.Stringify(diag.Error, d, args...)
if glog.V(5) {
glog.V(5).Infof("eventSink::Error(%v)", msg[:len(msg)-1])
}
s.events <- diagErrorEvent(s.opts.Colors, msg)
s.incrementCount(diag.Error)
}
func (s *eventSink) Warningf(d *diag.Diag, args ...interface{}) {
msg := s.Stringify(diag.Warning, d, args...)
if glog.V(5) {
glog.V(5).Infof("eventSink::Warning(%v)", msg[:len(msg)-1])
}
s.events <- diagWarningEvent(s.opts.Colors, msg)
s.incrementCount(diag.Warning)
}
func (s *eventSink) incrementCount(sev diag.Severity) {
s.mutex.Lock()
defer s.mutex.Unlock()
s.counts[sev]++
}
func (s *eventSink) getCount(sev diag.Severity) int {
s.mutex.RLock()
defer s.mutex.RUnlock()
return s.counts[sev]
}
func (s *eventSink) useColor(sev diag.Severity) bool {
// we will use color so long as we're not spewing to debug (which is colorless).
return s.opts.Colors
}
func (s *eventSink) Stringify(sev diag.Severity, d *diag.Diag, args ...interface{}) string {
var buffer bytes.Buffer
// First print the location if there is one.
if d.Doc != nil || d.Loc != nil {
buffer.WriteString(s.StringifyLocation(sev, d.Doc, d.Loc))
buffer.WriteString(": ")
}
// Now print the message category's prefix (error/warning).
if s.useColor(sev) {
switch sev {
case diag.Debug:
buffer.WriteString(colors.SpecDebug)
case diag.Info, diag.Infoerr:
buffer.WriteString(colors.SpecInfo)
case diag.Error:
buffer.WriteString(colors.SpecError)
case diag.Warning:
buffer.WriteString(colors.SpecWarning)
default:
contract.Failf("Unrecognized diagnostic severity: %v", sev)
}
}
buffer.WriteString(string(sev))
if d.ID > 0 {
buffer.WriteString(" ")
buffer.WriteString(eventSinkIDPrefix)
buffer.WriteString(strconv.Itoa(int(d.ID)))
}
buffer.WriteString(": ")
if s.useColor(sev) {
buffer.WriteString(colors.Reset)
}
// Finally, actually print the message itself.
if s.useColor(sev) {
buffer.WriteString(colors.SpecNote)
}
buffer.WriteString(fmt.Sprintf(d.Message, args...))
if s.useColor(sev) {
buffer.WriteString(colors.Reset)
}
buffer.WriteRune('\n')
// TODO[pulumi/pulumi#15]: support Clang-style expressive diagnostics. This would entail, for example, using
// the buffer within the target document, to demonstrate the offending line/column range of code.
return buffer.String()
}
func (s *eventSink) StringifyLocation(sev diag.Severity, doc *diag.Document, loc *diag.Location) string {
var buffer bytes.Buffer
if doc != nil {
if s.useColor(sev) {
buffer.WriteString(colors.SpecLocation)
}
file := doc.File
if s.opts.Pwd != "" {
// If a PWD is available, try to create a relative path.
rel, err := filepath.Rel(s.opts.Pwd, file)
if err == nil {
file = rel
}
}
buffer.WriteString(file)
}
if loc != nil && !loc.IsEmpty() {
buffer.WriteRune('(')
buffer.WriteString(strconv.Itoa(loc.Start.Line))
buffer.WriteRune(',')
buffer.WriteString(strconv.Itoa(loc.Start.Column))
buffer.WriteRune(')')
}
// Reset the color if we wrote anything
if buffer.Len() > 0 && s.useColor(sev) {
buffer.WriteString(colors.Reset)
}
return buffer.String()
}