grafana/pkg/services/rendering/rendering.go
2024-05-14 07:24:18 -03:00

466 lines
13 KiB
Go

package rendering
import (
"context"
"encoding/gob"
"errors"
"fmt"
"math"
"net/url"
"os"
"path/filepath"
"strings"
"sync"
"sync/atomic"
"time"
"github.com/grafana/grafana/pkg/infra/log"
"github.com/grafana/grafana/pkg/infra/metrics"
"github.com/grafana/grafana/pkg/infra/remotecache"
"github.com/grafana/grafana/pkg/models"
"github.com/grafana/grafana/pkg/plugins/backendplugin/pluginextensionv2"
"github.com/grafana/grafana/pkg/services/featuremgmt"
"github.com/grafana/grafana/pkg/setting"
"github.com/grafana/grafana/pkg/util"
)
var _ Service = (*RenderingService)(nil)
type RenderingService struct {
log log.Logger
plugin Plugin
renderAction renderFunc
renderCSVAction renderCSVFunc
sanitizeSVGAction sanitizeFunc
sanitizeURL string
domain string
inProgressCount int32
version string
versionMutex sync.RWMutex
capabilities []Capability
pluginAvailable bool
perRequestRenderKeyProvider renderKeyProvider
Cfg *setting.Cfg
features featuremgmt.FeatureToggles
RemoteCacheService *remotecache.RemoteCache
RendererPluginManager PluginManager
}
type PluginManager interface {
Renderer(ctx context.Context) (Plugin, bool)
}
type Plugin interface {
Client() (pluginextensionv2.RendererPlugin, error)
Start(ctx context.Context) error
Version() string
}
func ProvideService(cfg *setting.Cfg, features featuremgmt.FeatureToggles, remoteCache *remotecache.RemoteCache, rm PluginManager) (*RenderingService, error) {
folders := []string{
cfg.ImagesDir,
cfg.CSVsDir,
cfg.PDFsDir,
}
// ensure folders exists
for _, f := range folders {
err := os.MkdirAll(f, 0700)
if err != nil {
return nil, fmt.Errorf("failed to create directory %q: %w", f, err)
}
}
logger := log.New("rendering")
// URL for HTTP sanitize API
var sanitizeURL string
// value used for domain attribute of renderKey cookie
var domain string
switch {
case cfg.RendererUrl != "":
// RendererCallbackUrl has already been passed, it won't generate an error.
u, err := url.Parse(cfg.RendererCallbackUrl)
if err != nil {
return nil, err
}
sanitizeURL = getSanitizerURL(cfg.RendererUrl)
domain = u.Hostname()
case cfg.HTTPAddr != setting.DefaultHTTPAddr:
domain = cfg.HTTPAddr
default:
domain = "localhost"
}
var renderKeyProvider renderKeyProvider
if features.IsEnabledGlobally(featuremgmt.FlagRenderAuthJWT) {
renderKeyProvider = &jwtRenderKeyProvider{
log: logger,
authToken: []byte(cfg.RendererAuthToken),
keyExpiry: cfg.RendererRenderKeyLifeTime,
}
} else {
renderKeyProvider = &perRequestRenderKeyProvider{
cache: remoteCache,
log: logger,
keyExpiry: cfg.RendererRenderKeyLifeTime,
}
}
_, exists := rm.Renderer(context.Background())
s := &RenderingService{
perRequestRenderKeyProvider: renderKeyProvider,
capabilities: []Capability{
{
name: FullHeightImages,
semverConstraint: ">= 3.4.0",
},
{
name: ScalingDownImages,
semverConstraint: ">= 3.4.0",
},
{
name: SVGSanitization,
semverConstraint: ">= 3.5.0",
},
{
name: PDFRendering,
semverConstraint: ">= 3.10.0",
},
},
Cfg: cfg,
features: features,
RemoteCacheService: remoteCache,
RendererPluginManager: rm,
log: logger,
domain: domain,
sanitizeURL: sanitizeURL,
pluginAvailable: exists,
}
gob.Register(&RenderUser{})
return s, nil
}
func getSanitizerURL(rendererURL string) string {
rendererBaseURL := strings.TrimSuffix(rendererURL, "/render")
return rendererBaseURL + "/sanitize"
}
func (rs *RenderingService) Run(ctx context.Context) error {
if rs.remoteAvailable() {
rs.log = rs.log.New("renderer", "http")
rs.getRemotePluginVersionWithRetry(func(version string, err error) {
if err != nil {
rs.log.Info("Couldn't get remote renderer version", "err", err)
}
rs.log.Info("Backend rendering via external http server", "version", version)
rs.versionMutex.Lock()
defer rs.versionMutex.Unlock()
rs.version = version
})
rs.renderAction = rs.renderViaHTTP
rs.renderCSVAction = rs.renderCSVViaHTTP
rs.sanitizeSVGAction = rs.sanitizeViaHTTP
refreshTicker := time.NewTicker(remoteVersionRefreshInterval)
for {
select {
case <-refreshTicker.C:
go rs.refreshRemotePluginVersion()
case <-ctx.Done():
rs.log.Debug("Grafana is shutting down - stopping image-renderer version refresh")
refreshTicker.Stop()
return nil
}
}
}
if rp, exists := rs.RendererPluginManager.Renderer(ctx); exists {
rs.log = rs.log.New("renderer", "plugin")
rs.plugin = rp
if err := rs.plugin.Start(ctx); err != nil {
return err
}
rs.version = rp.Version()
rs.renderAction = rs.renderViaPlugin
rs.renderCSVAction = rs.renderCSVViaPlugin
rs.sanitizeSVGAction = rs.sanitizeSVGViaPlugin
<-ctx.Done()
return nil
}
rs.log.Debug("No image renderer found/installed. " +
"For image rendering support please install the grafana-image-renderer plugin. " +
"Read more at https://grafana.com/docs/grafana/latest/administration/image_rendering/")
<-ctx.Done()
return nil
}
func (rs *RenderingService) remoteAvailable() bool {
return rs.Cfg.RendererUrl != ""
}
func (rs *RenderingService) IsAvailable(ctx context.Context) bool {
return rs.remoteAvailable() || rs.pluginAvailable
}
func (rs *RenderingService) Version() string {
rs.versionMutex.RLock()
defer rs.versionMutex.RUnlock()
return rs.version
}
func (rs *RenderingService) RenderErrorImage(theme models.Theme, err error) (*RenderResult, error) {
if theme == "" {
theme = models.ThemeDark
}
imgUrl := "public/img/rendering_%s_%s.png"
if errors.Is(err, ErrTimeout) || errors.Is(err, ErrServerTimeout) {
imgUrl = fmt.Sprintf(imgUrl, "timeout", theme)
} else {
imgUrl = fmt.Sprintf(imgUrl, "error", theme)
}
imgPath := filepath.Join(rs.Cfg.HomePath, imgUrl)
if _, err := os.Stat(imgPath); errors.Is(err, os.ErrNotExist) {
return nil, err
}
return &RenderResult{
FilePath: imgPath,
}, nil
}
func (rs *RenderingService) renderUnavailableImage() *RenderResult {
imgPath := "public/img/rendering_plugin_not_installed.png"
return &RenderResult{
FilePath: filepath.Join(rs.Cfg.HomePath, imgPath),
}
}
// Render calls the grafana image renderer and returns Grafana resource as PNG or PDF
func (rs *RenderingService) Render(ctx context.Context, renderType RenderType, opts Opts, session Session) (*RenderResult, error) {
startTime := time.Now()
renderKeyProvider := rs.perRequestRenderKeyProvider
if session != nil {
renderKeyProvider = session
}
result, err := rs.render(ctx, renderType, opts, renderKeyProvider)
elapsedTime := time.Since(startTime).Milliseconds()
saveMetrics(elapsedTime, err, renderType)
return result, err
}
func (rs *RenderingService) render(ctx context.Context, renderType RenderType, opts Opts, renderKeyProvider renderKeyProvider) (*RenderResult, error) {
if int(atomic.LoadInt32(&rs.inProgressCount)) > opts.ConcurrentLimit {
rs.log.Warn("Could not render image, hit the currency limit", "concurrencyLimit", opts.ConcurrentLimit, "path", opts.Path)
if opts.ErrorConcurrentLimitReached {
return nil, ErrConcurrentLimitReached
}
theme := models.ThemeDark
if opts.Theme != "" {
theme = opts.Theme
}
filePath := fmt.Sprintf("public/img/rendering_limit_%s.png", theme)
return &RenderResult{
FilePath: filepath.Join(rs.Cfg.HomePath, filePath),
}, nil
}
if !rs.IsAvailable(ctx) {
rs.log.Warn("Could not render image, no image renderer found/installed. " +
"For image rendering support please install the grafana-image-renderer plugin. " +
"Read more at https://grafana.com/docs/grafana/latest/administration/image_rendering/")
if opts.ErrorRenderUnavailable {
return nil, ErrRenderUnavailable
}
return rs.renderUnavailableImage(), nil
}
if renderType == RenderPDF {
if !rs.features.IsEnabled(ctx, featuremgmt.FlagNewPDFRendering) {
return nil, fmt.Errorf("feature 'newPDFRendering' disabled")
}
if err := rs.IsCapabilitySupported(ctx, PDFRendering); err != nil {
return nil, err
}
}
rs.log.Info("Rendering", "path", opts.Path)
if math.IsInf(opts.DeviceScaleFactor, 0) || math.IsNaN(opts.DeviceScaleFactor) || opts.DeviceScaleFactor == 0 {
opts.DeviceScaleFactor = 1
}
renderKey, err := renderKeyProvider.get(ctx, opts.AuthOpts)
if err != nil {
return nil, err
}
defer renderKeyProvider.afterRequest(ctx, opts.AuthOpts, renderKey)
defer func() {
metrics.MRenderingQueue.Set(float64(atomic.AddInt32(&rs.inProgressCount, -1)))
}()
metrics.MRenderingQueue.Set(float64(atomic.AddInt32(&rs.inProgressCount, 1)))
return rs.renderAction(ctx, renderType, renderKey, opts)
}
func (rs *RenderingService) RenderCSV(ctx context.Context, opts CSVOpts, session Session) (*RenderCSVResult, error) {
startTime := time.Now()
renderKeyProvider := rs.perRequestRenderKeyProvider
if session != nil {
renderKeyProvider = session
}
result, err := rs.renderCSV(ctx, opts, renderKeyProvider)
elapsedTime := time.Since(startTime).Milliseconds()
saveMetrics(elapsedTime, err, RenderCSV)
return result, err
}
func (rs *RenderingService) SanitizeSVG(ctx context.Context, req *SanitizeSVGRequest) (*SanitizeSVGResponse, error) {
capability, err := rs.HasCapability(ctx, SVGSanitization)
if err != nil {
return nil, err
}
if !capability.IsSupported {
return nil, fmt.Errorf("svg sanitization unsupported, requires image renderer version: %s", capability.SemverConstraint)
}
start := time.Now()
action, err := rs.sanitizeSVGAction(ctx, req)
rs.log.Info("svg sanitization finished", "duration", time.Since(start), "filename", req.Filename, "isError", err != nil)
return action, err
}
func (rs *RenderingService) renderCSV(ctx context.Context, opts CSVOpts, renderKeyProvider renderKeyProvider) (*RenderCSVResult, error) {
if int(atomic.LoadInt32(&rs.inProgressCount)) > opts.ConcurrentLimit {
return nil, ErrConcurrentLimitReached
}
if !rs.IsAvailable(ctx) {
return nil, ErrRenderUnavailable
}
rs.log.Info("Rendering", "path", opts.Path)
renderKey, err := renderKeyProvider.get(ctx, opts.AuthOpts)
if err != nil {
return nil, err
}
defer renderKeyProvider.afterRequest(ctx, opts.AuthOpts, renderKey)
defer func() {
metrics.MRenderingQueue.Set(float64(atomic.AddInt32(&rs.inProgressCount, -1)))
}()
metrics.MRenderingQueue.Set(float64(atomic.AddInt32(&rs.inProgressCount, 1)))
return rs.renderCSVAction(ctx, renderKey, opts)
}
func (rs *RenderingService) getNewFilePath(rt RenderType) (string, error) {
rand, err := util.GetRandomString(20)
if err != nil {
return "", err
}
var ext string
var folder string
switch rt {
case RenderCSV:
ext = "csv"
folder = rs.Cfg.CSVsDir
case RenderPDF:
ext = "pdf"
folder = rs.Cfg.PDFsDir
default:
ext = "png"
folder = rs.Cfg.ImagesDir
}
return filepath.Abs(filepath.Join(folder, fmt.Sprintf("%s.%s", rand, ext)))
}
// getGrafanaCallbackURL creates a URL to send to the image rendering as callback for rendering a Grafana resource
func (rs *RenderingService) getGrafanaCallbackURL(path string) string {
if rs.Cfg.RendererUrl != "" {
// The backend rendering service can potentially be remote.
// So we need to use the root_url to ensure the rendering service
// can reach this Grafana instance.
// &render=1 signals to the legacy redirect layer to
return fmt.Sprintf("%s%s&render=1", rs.Cfg.RendererCallbackUrl, path)
}
protocol := rs.Cfg.Protocol
switch protocol {
case setting.HTTPScheme:
protocol = "http"
case setting.HTTP2Scheme, setting.HTTPSScheme:
protocol = "https"
default:
// TODO: Handle other schemes?
}
subPath := ""
if rs.Cfg.ServeFromSubPath {
subPath = rs.Cfg.AppSubURL
}
// &render=1 signals to the legacy redirect layer to
return fmt.Sprintf("%s://%s:%s%s/%s&render=1", protocol, rs.domain, rs.Cfg.HTTPPort, subPath, path)
}
func isoTimeOffsetToPosixTz(isoOffset string) string {
// invert offset
if strings.HasPrefix(isoOffset, "UTC+") {
return strings.Replace(isoOffset, "UTC+", "UTC-", 1)
}
if strings.HasPrefix(isoOffset, "UTC-") {
return strings.Replace(isoOffset, "UTC-", "UTC+", 1)
}
return isoOffset
}
func saveMetrics(elapsedTime int64, err error, renderType RenderType) {
if err == nil {
metrics.MRenderingRequestTotal.WithLabelValues("success", string(renderType)).Inc()
metrics.MRenderingSummary.WithLabelValues("success", string(renderType)).Observe(float64(elapsedTime))
return
}
if errors.Is(err, ErrTimeout) {
metrics.MRenderingRequestTotal.WithLabelValues("timeout", string(renderType)).Inc()
metrics.MRenderingSummary.WithLabelValues("timeout", string(renderType)).Observe(float64(elapsedTime))
} else {
metrics.MRenderingRequestTotal.WithLabelValues("failure", string(renderType)).Inc()
metrics.MRenderingSummary.WithLabelValues("failure", string(renderType)).Observe(float64(elapsedTime))
}
}