extractor rewrite (use custom wrappers over playwright locator)

This commit is contained in:
Egor Aristov 2025-02-09 10:42:42 +03:00
parent af4c94ac24
commit 8437f89bfa
3 changed files with 225 additions and 163 deletions

View File

@ -75,7 +75,9 @@ func main() {
} }
}() }()
start := time.Now()
result, err := pwe.Extract(task) result, err := pwe.Extract(task)
log.Infof("Extract took %v ms", time.Since(start).Milliseconds())
if err != nil { if err != nil {
log.Errorf("extract: %v", err) log.Errorf("extract: %v", err)
scrResult, err := pwe.Screenshot(task) scrResult, err := pwe.Screenshot(task)

View File

@ -0,0 +1,223 @@
package pwextractor
import (
"context"
_ "embed"
"fmt"
"github.com/egor3f/rssalchemy/internal/models"
"github.com/labstack/gommon/log"
"github.com/playwright-community/playwright-go"
)
// Timeouts
var (
defTimeout = "100ms"
)
type pageParser struct {
task models.Task
page playwright.Page
dateParser DateParser
// next fields only for debugging. Shit code, to do better later
postIdx int
fieldIdx int
}
func (p *pageParser) parse() (*models.TaskResult, error) {
var result models.TaskResult
var err error
p.waitFullLoad()
result.Title, err = p.page.Title()
if err != nil {
return nil, fmt.Errorf("page title: %w", err)
}
iconUrl, err := p.page.Locator("link[rel=apple-touch-icon]").First().
GetAttribute("href", playwright.LocatorGetAttributeOptions{Timeout: pwDuration("100ms")})
if err != nil {
log.Warnf("page icon url: %v", err)
} else {
result.Icon = absUrl(iconUrl, p.page)
}
posts, err := p.page.Locator(p.task.SelectorPost).All()
if err != nil {
return nil, fmt.Errorf("post locator: %w", err)
}
if len(posts) == 0 {
return nil, fmt.Errorf("no posts on page")
}
log.Debugf("Posts count=%d", len(posts))
for _, post := range posts {
item, err := p.extractPost(post)
if err != nil {
log.Errorf("extract post fields: %v", err)
continue
}
if len(item.Title) == 0 || len(item.Link) == 0 || item.Created.IsZero() {
log.Warnf("post has no required fields, skip")
continue
}
result.Items = append(result.Items, item)
}
return &result, nil
}
func (p *pageParser) waitFullLoad() {
timeout := pwDuration("5s")
ctx, cancel := context.WithCancel(context.Background())
go func() {
err := p.page.WaitForLoadState(playwright.PageWaitForLoadStateOptions{
State: playwright.LoadStateNetworkidle,
Timeout: timeout,
})
log.Debugf("WaitFor LoadState finished with %v", err)
cancel()
}()
go func() {
err := p.page.Locator(p.task.SelectorPost).Locator(p.task.SelectorTitle).Last().WaitFor(
playwright.LocatorWaitForOptions{
State: playwright.WaitForSelectorStateVisible,
Timeout: timeout,
},
)
log.Debugf("WaitFor LOCATOR finished with %v", err)
cancel()
}()
<-ctx.Done()
}
func (p *pageParser) extractPost(post playwright.Locator) (models.FeedItem, error) {
p.fieldIdx = 0
p.postIdx++
var item models.FeedItem
item.Title = newLocator(post, p.task.SelectorTitle).First().InnerText()
log.Debugf("---- POST: %s ----", item.Title)
item.Link = newLocator(post, p.task.SelectorLink).First().GetAttribute("href")
page, _ := post.Page()
item.Link = absUrl(item.Link, page)
if len(p.task.SelectorDescription) > 0 {
item.Description = newLocator(post, p.task.SelectorDescription).First().InnerText()
}
item.AuthorName = newLocator(post, p.task.SelectorAuthor).First().InnerText()
item.AuthorLink = newLocator(post, p.task.SelectorAuthor).First().GetAttribute("href")
item.AuthorLink = absUrl(item.AuthorLink, page)
if len(p.task.SelectorContent) > 0 {
item.Content = p.extractContent(post)
}
item.Enclosure = newLocator(post, p.task.SelectorEnclosure).First().GetAttribute("src")
createdDateStr := newLocator(post, p.task.SelectorCreated).First().InnerText()
log.Debugf("date=%s", createdDateStr)
createdDate, err := p.dateParser.ParseDate(createdDateStr)
if err != nil {
log.Errorf("dateparser: %v", err)
} else {
item.Created = createdDate
}
return item, nil
}
//go:embed extract_post.js
var extractPostScript string
func (p *pageParser) extractContent(post playwright.Locator) string {
postContent := newLocator(post, p.task.SelectorContent)
result, err := postContent.Evaluate(
extractPostScript,
nil,
playwright.LocatorEvaluateOptions{Timeout: pwDuration("1s")},
)
if err != nil {
log.Errorf("extract post content: evaluate: %v", err)
return postContent.TextContent()
}
resString, ok := result.(string)
if !ok {
log.Errorf("extract post content: result type mismatch: %v", result)
}
return resString
}
type locator struct {
selector string
playwright.Locator
}
func newLocator(parent playwright.Locator, selector string) *locator {
return &locator{
selector: selector,
Locator: parent.Locator(selector),
}
}
func (l *locator) String() string {
return l.selector
}
func (l *locator) checkVisible() bool {
visible, err := l.IsVisible()
if err != nil {
log.Errorf("locator %s isVisible: %v", l, err)
return false
}
if !visible {
log.Warnf("locator %s is not visible", l)
}
return visible
}
func (l *locator) First() *locator {
return &locator{l.selector, l.Locator.First()}
}
func (l *locator) InnerText() string {
if !l.checkVisible() {
return ""
}
t, err := l.Locator.InnerText(playwright.LocatorInnerTextOptions{Timeout: pwDuration(defTimeout)})
if err != nil {
log.Errorf("locator %s innerText: %v", l, err)
return ""
}
return t
}
func (l *locator) GetAttribute(name string) string {
if !l.checkVisible() {
return ""
}
t, err := l.Locator.GetAttribute(name, playwright.LocatorGetAttributeOptions{Timeout: pwDuration(defTimeout)})
if err != nil {
log.Errorf("locator %s getAttribute %s: %v", l, name, err)
return ""
}
return t
}
func (l *locator) TextContent() string {
if !l.checkVisible() {
return ""
}
t, err := l.Locator.TextContent(playwright.LocatorTextContentOptions{Timeout: pwDuration(defTimeout)})
if err != nil {
log.Errorf("locator %s textContent: %v", l, err)
return ""
}
return t
}

View File

@ -1,8 +1,6 @@
package pwextractor package pwextractor
import ( import (
"context"
_ "embed"
"fmt" "fmt"
"github.com/egor3f/rssalchemy/internal/models" "github.com/egor3f/rssalchemy/internal/models"
"github.com/labstack/gommon/log" "github.com/labstack/gommon/log"
@ -12,14 +10,6 @@ import (
"time" "time"
) )
// Timeouts
var (
defTimeout = "50ms"
defOptInText = playwright.LocatorInnerTextOptions{Timeout: pwDuration(defTimeout)}
defOptTextCon = playwright.LocatorTextContentOptions{Timeout: pwDuration(defTimeout)}
defOptAttr = playwright.LocatorGetAttributeOptions{Timeout: pwDuration(defTimeout)}
)
var userAgent = "Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/132.0.0.0 Safari/537.36" var userAgent = "Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/132.0.0.0 Safari/537.36"
var secChUa = `"Chromium";v="132", "Google Chrome";v="132", "Not-A.Brand";v="99"` var secChUa = `"Chromium";v="132", "Google Chrome";v="132", "Not-A.Brand";v="99"`
@ -229,156 +219,3 @@ func (e *PwExtractor) Screenshot(task models.Task) (result *models.ScreenshotTas
}) })
return return
} }
type pageParser struct {
task models.Task
page playwright.Page
dateParser DateParser
// next fields only for debugging. Shit code, to do better later
postIdx int
fieldIdx int
}
// must accepts arbitrary string and error and returns just string, also logs everything.
// it is used for playwright functons that return both string and error to avoid boilerplate.
// fieldIdx is convinient variable used only for logging purposes, looks like shit, maybe i'll do it better later.
func (p *pageParser) must(s string, err error) string {
p.fieldIdx++
if err != nil {
log.Errorf("extract post field %d: %v", p.fieldIdx, err)
return ""
}
//log.Debugf("field=%d res=%.100s", p.fieldIdx, s)
return s
}
func (p *pageParser) parse() (*models.TaskResult, error) {
var result models.TaskResult
var err error
p.waitFullLoad()
result.Title, err = p.page.Title()
if err != nil {
return nil, fmt.Errorf("page title: %w", err)
}
iconUrl, err := p.page.Locator("link[rel=apple-touch-icon]").First().
GetAttribute("href", playwright.LocatorGetAttributeOptions{Timeout: pwDuration("100ms")})
if err != nil {
log.Warnf("page icon url: %v", err)
} else {
result.Icon = absUrl(iconUrl, p.page)
}
posts, err := p.page.Locator(p.task.SelectorPost).All()
if err != nil {
return nil, fmt.Errorf("post locator: %w", err)
}
if len(posts) == 0 {
return nil, fmt.Errorf("no posts on page")
}
log.Debugf("Posts count=%d", len(posts))
for _, post := range posts {
item, err := p.extractPost(post)
if err != nil {
log.Errorf("extract post fields: %v", err)
continue
}
if len(item.Title) == 0 || len(item.Link) == 0 || item.Created.IsZero() {
log.Warnf("post has no required fields, skip")
continue
}
result.Items = append(result.Items, item)
}
return &result, nil
}
func (p *pageParser) waitFullLoad() {
timeout := pwDuration("5s")
ctx, cancel := context.WithCancel(context.Background())
go func() {
err := p.page.WaitForLoadState(playwright.PageWaitForLoadStateOptions{
State: playwright.LoadStateNetworkidle,
Timeout: timeout,
})
log.Debugf("WaitFor LoadState finished with %v", err)
cancel()
}()
go func() {
err := p.page.Locator(p.task.SelectorPost).Locator(p.task.SelectorTitle).Last().WaitFor(
playwright.LocatorWaitForOptions{
State: playwright.WaitForSelectorStateVisible,
Timeout: timeout,
},
)
log.Debugf("WaitFor LOCATOR finished with %v", err)
cancel()
}()
<-ctx.Done()
}
func (p *pageParser) extractPost(post playwright.Locator) (models.FeedItem, error) {
p.fieldIdx = 0
p.postIdx++
var item models.FeedItem
item.Title = p.must(post.Locator(p.task.SelectorTitle).First().InnerText(defOptInText))
log.Debugf("---- POST: %s ----", item.Title)
item.Link = p.must(post.Locator(p.task.SelectorLink).First().GetAttribute("href", defOptAttr))
page, _ := post.Page()
item.Link = absUrl(item.Link, page)
if len(p.task.SelectorDescription) > 0 {
item.Description = p.must(post.Locator(p.task.SelectorDescription).First().InnerText(defOptInText))
}
item.AuthorName = p.must(post.Locator(p.task.SelectorAuthor).First().InnerText(defOptInText))
item.AuthorLink = p.must(post.Locator(p.task.SelectorAuthor).First().GetAttribute("href", defOptAttr))
item.AuthorLink = absUrl(item.AuthorLink, page)
if len(p.task.SelectorContent) > 0 {
item.Content = p.extractContent(post)
}
item.Enclosure = p.must(post.Locator(p.task.SelectorEnclosure).First().GetAttribute("src", defOptAttr))
createdDateStr := p.must(post.Locator(p.task.SelectorCreated).First().InnerText(defOptInText))
log.Debugf("date=%s", createdDateStr)
createdDate, err := p.dateParser.ParseDate(createdDateStr)
if err != nil {
log.Errorf("dateparser: %v", err)
} else {
item.Created = createdDate
}
return item, nil
}
//go:embed extract_post.js
var extractPostScript string
func (p *pageParser) extractContent(post playwright.Locator) string {
postContent := post.Locator(p.task.SelectorContent)
result, err := postContent.Evaluate(
extractPostScript,
nil,
playwright.LocatorEvaluateOptions{Timeout: pwDuration("1s")},
)
if err != nil {
log.Errorf("extract post content: evaluate: %v", err)
return p.must(postContent.TextContent(defOptTextCon))
}
resString, ok := result.(string)
if !ok {
log.Errorf("extract post content: result type mismatch: %v", result)
}
return resString
}