preview

package
v0.2.0-beta.17 Latest Latest
Warning

This package is not in the latest version of its module.

 Go to latest Published: Oct 5, 2026 License: Apache-2.0 Imports: 36 Imported by: 0

Documentation

Overview

Package preview captures a thumbnail of each deployed release with a short-lived browser container and keeps them within bounded storage.

Index

Constants

View Source 
const (
	EnvEnabled       = "APP_PREVIEW_ENABLED"
	EnvImage         = "APP_PREVIEW_IMAGE"
	EnvTimeout       = "APP_PREVIEW_TIMEOUT"
	EnvPullTimeout   = "APP_PREVIEW_PULL_TIMEOUT"
	EnvMemoryMB      = "APP_PREVIEW_MEMORY_MB"
	EnvCPUs          = "APP_PREVIEW_CPUS"
	EnvViewport      = "APP_PREVIEW_VIEWPORT"
	EnvThumbWidth    = "APP_PREVIEW_THUMB_WIDTH"
	EnvQuality       = "APP_PREVIEW_QUALITY"
	EnvMaxThumbKB    = "APP_PREVIEW_MAX_THUMB_KB"
	EnvBlankRatio    = "APP_PREVIEW_BLANK_RATIO"
	EnvKeepPerApp    = "APP_PREVIEW_KEEP_PER_APP"
	EnvTTLDays       = "APP_PREVIEW_TTL_DAYS"
	EnvMaxTotalMB    = "APP_PREVIEW_MAX_TOTAL_MB"
	EnvImageTTLDays  = "APP_PREVIEW_IMAGE_TTL_DAYS"
	EnvMinFreeRAMMB  = "APP_PREVIEW_MIN_FREE_RAM_MB"
	EnvMinFreeDiskMB = "APP_PREVIEW_MIN_FREE_DISK_MB"
	EnvQueueDepth    = "APP_PREVIEW_QUEUE_DEPTH"
	EnvSweepInterval = "APP_PREVIEW_SWEEP_INTERVAL"
	EnvDefaultMode   = "APP_PREVIEW_DEFAULT_MODE"
	EnvThumbHeight   = "APP_PREVIEW_THUMB_HEIGHT"
	EnvMetaTimeout   = "APP_PREVIEW_META_TIMEOUT"
	EnvMetaMaxHTMLKB = "APP_PREVIEW_META_MAX_HTML_KB"
	EnvMetaMaxImgKB  = "APP_PREVIEW_META_MAX_IMAGE_KB"
	EnvMetaRedirects = "APP_PREVIEW_META_MAX_REDIRECTS"
	EnvMetaMinImgPx  = "APP_PREVIEW_META_MIN_IMAGE_PX"
)

Environment variables ConfigFromEnv reads.

View Source 
const (
	EvictKeepLimit = "keep_limit"
	EvictTTL       = "ttl"
	EvictBudget    = "budget"
)

Eviction reasons.

View Source 
const (
	StatusOK      = "ok"
	StatusSkipped = "skipped"
	StatusFailed  = "failed"
)

Record statuses.

View Source 
const (
	ReasonLowRAM        = "low_ram"
	ReasonLowDisk       = "low_disk"
	ReasonImageUnusable = "browser_image_unavailable"
	ReasonNoAppNetwork  = "no_app_network"
	ReasonRemoteNode    = "remote_node"
	ReasonUnreachable   = "unreachable"
	ReasonHTTPStatus    = "http_status"
	ReasonAuthWall      = "auth_wall"
	ReasonBlankImage    = "blank_image"
	ReasonBadImage      = "bad_image"
	ReasonTimeout       = "timeout"
	ReasonNotHTML       = "not_html"
	ReasonRedirect      = "redirect"
	ReasonCaptureFailed = "capture_failed"
)

Skip and failure reason codes stored on a Record.

View Source 
const (
	SourceScreenshot = "screenshot"
	SourceOGImage    = "og_image"
	SourceCard       = "card"
)

Record sources: where a preview's pixels came from.

View Source 
const (
	DefaultPath = "/"
	MaxPathLen  = 512
	MaxWaitMS   = 10000
)

Bounds on the per-app capture options.

View Source 
const DefaultImage = "docker.io/chromedp/headless-shell:151.0.7922.109"

DefaultImage is the pinned capture browser; override with APP_PREVIEW_IMAGE.

Variables

View Source 
var ErrBadRef = errors.New("preview: unusable reference")

ErrBadRef means a reference is not a fetchable http(s) URL.

View Source 
var ErrBlankImage = errors.New("preview: capture is blank")

ErrBlankImage means the capture is a single flat color.

View Source 
var ErrDisabled = errors.New("preview: disabled")

ErrDisabled means previews are switched off, globally or for the app.

View Source 
var ErrInvalid = errors.New("preview: invalid setting")

ErrInvalid wraps every settings validation failure.

View Source 
var ErrNotFound = errors.New("preview: not found")

ErrNotFound means no preview exists for the requested deployment.

View Source 
var ErrNotHTML = errors.New("preview: page is not HTML")

ErrNotHTML means the page answered with something other than HTML.

View Source 
var ErrTinyImage = errors.New("preview: image is too small")

ErrTinyImage means a fetched image is too small to be a useful thumbnail.

Functions

func IsBlank 

func IsBlank(img image.Image, ratio float64) bool

IsBlank reports whether one color (quantized to 4 bits per channel) covers at least ratio of a sampled grid of img.

func ResolveRef 

func ResolveRef(base *url.URL, raw string) (*url.URL, error)

ResolveRef resolves raw against base and accepts only absolute http(s) URLs without credentials. A literal internal IP is refused here; DNS names that resolve internally are refused by the guarded dialer.

func ValidatePath 

func ValidatePath(p string) error

ValidatePath rejects anything that is not an absolute path on the app itself.

Types

type AppSettings 

type AppSettings struct {
	App string
	// Mode is the preview tier. Enabled is derived from it (Mode != off) and
	// kept for callers written before tiers existed.
	Mode    Mode
	Enabled bool
	Path    string
	WaitMS  int
}

AppSettings is one app's opt-in and capture options.

func (*AppSettings) Normalize 

func (s *AppSettings) Normalize(def Mode, configured bool)

Normalize fills Mode and Enabled from each other. A zero Mode with Enabled unset takes def when the app was never configured, and off otherwise.

func (AppSettings) Validate 

func (s AppSettings) Validate() error

Validate checks settings before they are stored.

type Browser 

type Browser interface {
	// Endpoint is the host address of the browser's debugging port.
	Endpoint() string
	Close()
}

Browser is a running capture browser.

type CDPShooter 

type CDPShooter struct{}

CDPShooter speaks the Chrome DevTools Protocol over a websocket.

func (CDPShooter) Shoot 

func (CDPShooter) Shoot(ctx context.Context, addr string, req ShotRequest) (*ShotResult, error)

Shoot loads req.URL, waits for the page to settle and returns a PNG of the viewport plus the main document's final HTTP status.

type CardMeta 

type CardMeta struct {
	Title       string `json:"title,omitempty"`
	Description string `json:"description,omitempty"`
	ThemeColor  string `json:"theme_color,omitempty"`
}

CardMeta is the page metadata a card preview is composed from in the UI.

type Config 

type Config struct {
	Enabled       bool
	Image         string
	Timeout       time.Duration
	PullTimeout   time.Duration
	MemoryMB      int64
	CPUs          float64
	ViewportW     int
	ViewportH     int
	ThumbWidth    int
	Quality       int
	MaxThumbKB    int
	BlankRatio    float64
	KeepPerApp    int
	TTL           time.Duration
	MaxTotalBytes int64
	ImageTTL      time.Duration
	MinFreeRAM    int64
	MinFreeDisk   int64
	QueueDepth    int
	SweepInterval time.Duration

	DefaultMode  Mode
	ThumbHeight  int
	MetaTimeout  time.Duration
	MetaMaxHTML  int64
	MetaMaxImage int64
	MetaRedirect int
	MetaMinImgPx int
}

Config holds every preview threshold. ConfigFromEnv fills defaults, so a Manager never sees a zero value it has to interpret.

func ConfigFromEnv 

func ConfigFromEnv(lookup func(string) (string, bool), logger *slog.Logger) Config

ConfigFromEnv reads Config from lookup (os.LookupEnv in production). Unset or malformed values fall back to the defaults.

type Deps 

type Deps struct {
	Store    Store
	Resolver Resolver
	Runner   Runner
	// DataDir is the platform data directory; thumbnails live in DataDir/previews.
	DataDir string
	// Namespace prefixes the labels on capture containers (the brand short name).
	Namespace string
	Logger    *slog.Logger
}

Deps are the collaborators a Manager needs.

type Eviction 

type Eviction struct {
	Record Record
	Reason string
}

Eviction is one record PlanEviction wants deleted and why.

func PlanEviction 

func PlanEviction(records []Record, protected map[string]bool, now time.Time, p RetentionPolicy) []Eviction

PlanEviction picks the records to delete. Protected deployments (the current production release of each app) are never evicted and do not count against KeepPerApp. Order of rules: per-app keep limit, TTL, then the global byte budget by least recently used.

type FileEntry 

type FileEntry struct {
	App          string
	DeploymentID string
	Size         int64
}

FileEntry is one thumbnail file found on disk.

type FileStore 

type FileStore struct {
	// contains filtered or unexported fields
}

FileStore keeps thumbnails at <root>/<app>/<deployment>.jpg.

func NewFileStore 

func NewFileStore(root string) *FileStore

NewFileStore returns a store rooted at root, which is created on first write.

func (*FileStore) Exists 

func (f *FileStore) Exists(app, deploymentID string) bool

Exists reports whether the thumbnail file is present.

func (*FileStore) List 

func (f *FileStore) List() ([]FileEntry, error)

List returns every thumbnail file on disk. Stray temp files are removed.

func (*FileStore) Path 

func (f *FileStore) Path(app, deploymentID string) (string, error)

Path returns the file path for a deployment, rejecting names that could escape the root.

func (*FileStore) Remove 

func (f *FileStore) Remove(app, deploymentID string) error

Remove deletes one thumbnail; a missing file is not an error.

func (*FileStore) RemoveApp 

func (f *FileStore) RemoveApp(app string) error

RemoveApp deletes every thumbnail of app.

func (*FileStore) RemoveEntry 

func (f *FileStore) RemoveEntry(e FileEntry) error

RemoveEntry deletes a file found by List, plus its app directory if empty.

func (*FileStore) Write 

func (f *FileStore) Write(app, deploymentID string, data []byte) error

Write stores data atomically.

type ImageState 

type ImageState struct {
	Ref      string
	ID       string
	LastUsed time.Time
}

ImageState is what the platform knows about the browser image it pulled.

type Manager 

type Manager struct {
	// contains filtered or unexported fields
}

Manager captures, stores and prunes deploy preview thumbnails. It holds no goroutine while idle: a worker exists only while jobs are queued, plus one coarse sweep ticker after Start.

func New 

func New(cfg Config, deps Deps, opts ...Option) *Manager

New builds a Manager. Nothing runs until a job is queued or Start is called.

func (*Manager) BrowserImage 

func (m *Manager) BrowserImage(ctx context.Context) ImageState

BrowserImage returns the tracked browser image, zero when none was pulled by this platform.

func (*Manager) Capture 

func (m *Manager) Capture(ctx context.Context, app string) error

Capture queues a manual recapture of app's current release.

func (*Manager) Capturing 

func (m *Manager) Capturing(app string) bool

Capturing reports whether a job for app is queued or running.

func (*Manager) Config 

func (m *Manager) Config() Config

Config returns the effective configuration.

func (*Manager) DeleteApp 

func (m *Manager) DeleteApp(ctx context.Context, app string) error

DeleteApp removes every preview of a deleted app.

func (*Manager) List 

func (m *Manager) List(ctx context.Context, app string) ([]Record, error)

List returns app's records, newest first.

func (*Manager) NotifyReady 

func (m *Manager) NotifyReady(app, image, runningImageID string)

NotifyReady is called each time an app's release is observed serving. It is cheap after the first call per release (image tag plus the running image ID, so a rebuilt mutable tag counts as a new release) and never blocks.

func (*Manager) OpenImage 

func (m *Manager) OpenImage(ctx context.Context, app, deploymentID string) (string, Record, error)

OpenImage returns the file path of an app's stored thumbnail. It marks the preview as viewed, at most once per viewedTouchAfter.

func (*Manager) Prune 

func (m *Manager) Prune(ctx context.Context, app string, all bool) (PruneResult, error)

Prune applies retention to app now. With all set it removes every preview of the app, including the current release's.

func (*Manager) SaveSettings 

func (m *Manager) SaveSettings(ctx context.Context, app string, patch SettingsPatch) (AppSettings, error)

SaveSettings applies patch to app's settings and stores the result.

func (*Manager) Settings 

func (m *Manager) Settings(ctx context.Context, app string) (AppSettings, error)

Settings returns app's settings, defaulting to off with path "/".

func (*Manager) Start 

func (m *Manager) Start(ctx context.Context)

Start runs a startup sweep and then one on every SweepInterval until ctx ends. It is the only long-lived goroutine.

func (*Manager) Status 

func (m *Manager) Status(ctx context.Context, app string) (Summary, error)

Status assembles the app-level summary.

func (*Manager) Storage 

func (m *Manager) Storage(ctx context.Context, app string) (appUsage, total Usage, err error)

Storage returns app's usage, and the global usage across all apps.

func (*Manager) Sweep 

func (m *Manager) Sweep(ctx context.Context)

Sweep runs every cleanup pass: retention, deleted apps, orphan files, orphan capture containers and the idle browser image.

type MetaFetcher 

type MetaFetcher interface {
	FetchPage(ctx context.Context, t MetaTarget, path string) (*PageResult, error)
	FetchImage(ctx context.Context, t MetaTarget, base *url.URL, ref string) ([]byte, error)
}

MetaFetcher fetches a page and its image for the metadata tier.

type MetaTarget 

type MetaTarget struct {
	DeploymentID string
	Image        string
	Dial         string
	Host         string
	Port         int
	Domains      []string
}

MetaTarget is where the metadata tier fetches an app's page: the app's published loopback port, with Host/Port/Domains naming its origins.

type Mode 

type Mode string

Mode is how much a per-app preview may cost. 

const (
	ModeOff        Mode = "off"
	ModeMetadata   Mode = "metadata"
	ModeScreenshot Mode = "screenshot"
)

Preview modes, cheapest first.

func ParseMode 

func ParseMode(s string) (Mode, error)

ParseMode validates a mode string.

type Option 

type Option func(*Manager)

Option adjusts a Manager, mainly for tests.

func WithClock 

func WithClock(now func() time.Time) Option

WithClock overrides the time source.

func WithHostProbes 

func WithHostProbes(mem func() (int64, int64, error), disk func(string) (int64, error)) Option

WithHostProbes overrides the free RAM and free disk readings.

func WithMetaFetcher 

func WithMetaFetcher(f MetaFetcher) Option

WithMetaFetcher overrides the metadata tier's HTTP client, mainly for tests.

func WithShooter 

func WithShooter(s Shooter) Option

WithShooter overrides the browser driver.

type PageMeta 

type PageMeta struct {
	Title        string
	OGTitle      string
	Description  string
	ThemeColor   string
	OGImage      string
	TwitterImage string
	Icon         string
}

PageMeta is what the metadata tier reads from a page's head. URL fields are raw and unresolved; use ResolveRef before fetching any of them.

func ParseMeta 

func ParseMeta(r io.Reader) PageMeta

ParseMeta tokenizes HTML from r and collects the head metadata it knows. It stops at the first body element or when r is exhausted.

func (PageMeta) DisplayTitle 

func (m PageMeta) DisplayTitle() string

DisplayTitle prefers og:title over the document title.

func (PageMeta) ImageRef 

func (m PageMeta) ImageRef() string

ImageRef is the raw image reference to try: og:image first, then twitter:image.

type PageResult 

type PageResult struct {
	HTTPStatus int
	// Base is the final page URL, on the app's own origin.
	Base *url.URL
	Meta PageMeta
}

PageResult is a fetched page's outcome.

type PruneResult 

type PruneResult struct {
	Removed    int
	FreedBytes int64
}

PruneResult reports what a prune removed.

type Record 

type Record struct {
	DeploymentID string
	App          string
	Path         string
	Bytes        int64
	Width        int
	Height       int
	Status       string
	Reason       string
	Detail       string
	HTTPStatus   int
	Source       string
	Meta         string
	CapturedAt   time.Time
	LastViewedAt time.Time
}

Record is one deployment's preview outcome. Only rows with HasFile own a file.

func (Record) HasFile 

func (r Record) HasFile() bool

HasFile reports whether the record has a thumbnail on disk. Card records are composed in the UI from Meta and store no file.

func (Record) LastUsed 

func (r Record) LastUsed() time.Time

LastUsed is the recency LRU eviction orders by.

type Resolver 

type Resolver interface {
	// Resolve returns the capture target for app's release currently
	// serving image ("" means whatever is current), or a *SkipError.
	Resolve(ctx context.Context, app, image string) (Target, error)
	// ResolveMeta is Resolve for the metadata tier: it needs no Docker
	// network, only a reachable published port.
	ResolveMeta(ctx context.Context, app, image string) (MetaTarget, error)
	// CurrentDeployment returns the deployment serving production, or "".
	CurrentDeployment(ctx context.Context, app string) (string, error)
	AppExists(ctx context.Context, app string) (bool, error)
}

Resolver maps an app to its live release and Docker network.

type RetentionPolicy 

type RetentionPolicy struct {
	KeepPerApp    int
	TTL           time.Duration
	MaxTotalBytes int64
}

RetentionPolicy bounds how many previews are kept.

type Runner 

type Runner interface {
	EnsureImageID(ctx context.Context, ref string) (id string, pulled bool, err error)
	StartBrowser(ctx context.Context, spec docker.BrowserSpec) (Browser, error)
	ListContainersByLabel(ctx context.Context, label string) ([]docker.LabeledContainer, error)
	Remove(ctx context.Context, id string, force bool) error
	ImageInUse(ctx context.Context, imageID string) (bool, error)
	RemoveImageByID(ctx context.Context, imageID string) error
}

Runner is the Docker surface previews use.

func NewDockerRunner 

func NewDockerRunner(c *docker.Client) Runner

NewDockerRunner returns a Runner backed by the real Docker client.

type SQLStore 

type SQLStore struct {
	// contains filtered or unexported fields
}

SQLStore implements Store over the control plane database.

func NewSQLStore 

func NewSQLStore(db *store.DB) *SQLStore

NewSQLStore wraps db.

func (*SQLStore) DeletePreviewRecords 

func (s *SQLStore) DeletePreviewRecords(ctx context.Context, ids []string) error

DeletePreviewRecords removes records by deployment ID.

func (*SQLStore) DeletePreviewSettings 

func (s *SQLStore) DeletePreviewSettings(ctx context.Context, app string) error

DeletePreviewSettings removes an app's settings, returning it to the default off state.

func (*SQLStore) GetPreviewRecord 

func (s *SQLStore) GetPreviewRecord(ctx context.Context, deploymentID string) (*Record, error)

GetPreviewRecord returns one record, or nil when absent.

func (*SQLStore) GetPreviewSettings 

func (s *SQLStore) GetPreviewSettings(ctx context.Context, app string) (AppSettings, error)

GetPreviewSettings returns the stored settings, or the zero value when none exist.

func (*SQLStore) GetPreviewState 

func (s *SQLStore) GetPreviewState(ctx context.Context, key string) (string, error)

GetPreviewState reads one state value, "" when unset.

func (*SQLStore) LatestServingDeployment 

func (s *SQLStore) LatestServingDeployment(ctx context.Context, service, image string) (string, error)

LatestServingDeployment is LatestSucceededDeployment restricted to attempts the controller has observed serving, so a preview is never filed under a release that has not replaced the old one yet.

func (*SQLStore) LatestSucceededDeployment 

func (s *SQLStore) LatestSucceededDeployment(ctx context.Context, service, image string) (string, error)

LatestSucceededDeployment returns the newest succeeded deploy attempt of service, restricted to image when non-empty. "" means none.

func (*SQLStore) ListAllPreviewRecords 

func (s *SQLStore) ListAllPreviewRecords(ctx context.Context) ([]Record, error)

ListAllPreviewRecords lists every record, newest first.

func (*SQLStore) ListPreviewRecords 

func (s *SQLStore) ListPreviewRecords(ctx context.Context, app string) ([]Record, error)

ListPreviewRecords lists one app's records, newest first.

func (*SQLStore) SavePreviewSettings 

func (s *SQLStore) SavePreviewSettings(ctx context.Context, a AppSettings) error

SavePreviewSettings upserts settings. The legacy enabled column stays true only for screenshot mode, so an older binary reading it behaves the same.

func (*SQLStore) SetPreviewState 

func (s *SQLStore) SetPreviewState(ctx context.Context, key, value string) error

SetPreviewState writes one state value.

func (*SQLStore) TouchPreviewViewed 

func (s *SQLStore) TouchPreviewViewed(ctx context.Context, deploymentID string, at time.Time) error

TouchPreviewViewed stamps the last time a preview image was served.

func (*SQLStore) UpsertPreviewRecord 

func (s *SQLStore) UpsertPreviewRecord(ctx context.Context, r Record) error

UpsertPreviewRecord inserts or replaces a record, keeping its view time.

type SettingsPatch 

type SettingsPatch struct {
	Mode    *string
	Enabled *bool
	Path    *string
	WaitMS  *int
}

SettingsPatch updates only the fields that are non-nil.

type Shooter 

type Shooter interface {
	Shoot(ctx context.Context, addr string, req ShotRequest) (*ShotResult, error)
}

Shooter drives a running browser, reachable at addr, to screenshot a page.

type ShotRequest 

type ShotRequest struct {
	URL      string
	Width    int
	Height   int
	Settle   time.Duration
	Deadline time.Time
}

ShotRequest is one page to screenshot.

type ShotResult 

type ShotResult struct {
	HTTPStatus int
	FinalURL   string
	PNG        []byte
}

ShotResult is what the browser saw and captured.

func (*ShotResult) Classify 

func (r *ShotResult) Classify(requestedPath string) (reason, detail string)

Classify says whether a browser result allows a thumbnail. A non-empty reason means skip. requestedPath is the path that was asked for: landing on a different login-looking path means an auth wall.

type SkipError 

type SkipError struct {
	DeploymentID string
	Reason       string
	Detail       string
}

SkipError tells the Manager a capture must not run, recording Reason against DeploymentID (empty means nothing is recorded).

func (*SkipError) Error 

func (e *SkipError) Error() string

type Store 

type Store interface {
	GetPreviewSettings(ctx context.Context, app string) (AppSettings, error)
	SavePreviewSettings(ctx context.Context, s AppSettings) error
	DeletePreviewSettings(ctx context.Context, app string) error
	UpsertPreviewRecord(ctx context.Context, r Record) error
	GetPreviewRecord(ctx context.Context, deploymentID string) (*Record, error)
	ListPreviewRecords(ctx context.Context, app string) ([]Record, error)
	ListAllPreviewRecords(ctx context.Context) ([]Record, error)
	DeletePreviewRecords(ctx context.Context, deploymentIDs []string) error
	TouchPreviewViewed(ctx context.Context, deploymentID string, at time.Time) error
	GetPreviewState(ctx context.Context, key string) (string, error)
	SetPreviewState(ctx context.Context, key, value string) error
}

Store persists settings, records and the small image-tracking state.

type Summary 

type Summary struct {
	Settings     AppSettings
	GlobalOn     bool
	Capturing    bool
	App, Total   Usage
	Image        string
	BrowserImage ImageState
	Latest       *Record
}

Summary is the app-level status shown in the UI and CLI.

type Target 

type Target struct {
	DeploymentID string
	Image        string
	Network      string
	Host         string
	Port         int
}

Target is where to point the browser for an app's current release.

type Thumb 

type Thumb struct {
	JPEG          []byte
	Width, Height int
}

Thumb is an encoded thumbnail.

func BuildThumb 

func BuildThumb(pngData []byte, thumbWidth, quality, maxBytes int, blankRatio float64) (*Thumb, error)

BuildThumb validates a PNG capture and returns a JPEG thumbnail of width thumbWidth. It re-encodes once at lower quality when the result exceeds maxBytes, and rejects it if it is still too large.

func BuildThumbFit 

func BuildThumbFit(data []byte, w, h, minPx, quality, maxBytes int, blankRatio float64) (*Thumb, error)

BuildThumbFit decodes a JPEG or PNG, scales it down to fit within w by h (never up) and centers it on a neutral w by h canvas. It rejects images under minPx on either side and single-color images.

type Usage 

type Usage struct {
	Bytes int64
	Count int
}

Usage is the storage a set of previews occupies.

Source Files

View all Source files

Jump to

Keyboard shortcuts

? : This menu
/ : Search site
f or F : Jump to
y or Y : Canonical URL
go.dev uses cookies from Google to deliver and enhance the quality of its services and to analyze traffic. Learn more.