def checkForLargeImages(self, node, parentDepthLevel, siblingDepthLevel):
"""\
although slow the best way to determine the best image is to download
them and check the actual dimensions of the image when on disk
so we'll go through a phased approach...
1. get a list of ALL images from the parent node
2. filter out any bad image names that we know of (gifs, ads, etc..)
3. do a head request on each file to make sure it meets
our bare requirements
4. any images left over let's do a full GET request,
download em to disk and check their dimensions
5. Score images based on different factors like height/width
and possibly things like color density
"""
goodImages = self.getImageCandidates(node)
if goodImages:
scoredImages = self.downloadImagesAndGetResults(goodImages, parentDepthLevel)
if scoredImages:
highScoreImage = sorted(scoredImages.items(),
key=lambda x: x[1], reverse=True)[0][0]
mainImage = Image()
mainImage.imageSrc = highScoreImage.imgSrc
mainImage.imageExtractionType = "bigimage"
mainImage.confidenceScore = 100 / len(scoredImages) \
if len(scoredImages) > 0 else 0
return mainImage
depthObj = self.getDepthLevel(node, parentDepthLevel, siblingDepthLevel)
if depthObj:
return self.checkForLargeImages(depthObj.node,
depthObj.parentDepth, depthObj.siblingDepth)
return None
def checkForOpenGraphTag(self):
"""\
checks to see if we were able to
find open graph tags on this page
"""
node = self.article.rawDoc
meta = Parser.getElementsByTag(node,
tag='meta',
attr='property',
value='og:image')
for item in meta:
href = Parser.getAttribute(item, attr='content')
if href:
mainImage = Image()
mainImage.imageSrc = href
mainImage.imageExtractionType = "opengraph"
mainImage.confidenceScore = 100
locallyStoredImage = self.getLocallyStoredImage(
mainImage.imageSrc)
if locallyStoredImage:
mainImage.bytes = locallyStoredImage.bytes
mainImage.height = locallyStoredImage.height
mainImage.width = locallyStoredImage.width
return mainImage
return None
def checkForLinkTag(self):
"""\
checks to see if we were able to
find open link_src on this page
"""
node = self.article.rawDoc
meta = Parser.getElementsByTag(node,
tag='link',
attr='rel',
value='image_src')
for item in meta:
href = Parser.getAttribute(item, attr='href')
if href:
mainImage = Image()
mainImage.imageSrc = href
mainImage.imageExtractionType = "linktag"
mainImage.confidenceScore = 100
locallyStoredImage = self.getLocallyStoredImage(
mainImage.imageSrc)
if locallyStoredImage:
mainImage.bytes = locallyStoredImage.bytes
mainImage.height = locallyStoredImage.height
mainImage.width = locallyStoredImage.width
return mainImage
return None
def getBestImage(self, doc, topNode):
image = self.checkForKnownElements()
if image:
return image
image = self.checkForLargeImages(topNode, 0, 0)
if image:
return image
image = self.checkForMetaTag()
if image:
return image
return Image()
def checkForLargeImages(self, node, parentDepthLevel, siblingDepthLevel):
"""\
although slow the best way to determine the best image is to download
them and check the actual dimensions of the image when on disk
so we'll go through a phased approach...
1. get a list of ALL images from the parent node
2. filter out any bad image names that we know of (gifs, ads, etc..)
3. do a head request on each file to make sure it meets
our bare requirements
4. any images left over let's do a full GET request,
download em to disk and check their dimensions
5. Score images based on different factors like height/width
and possibly things like color density
"""
goodImages = self.getImageCandidates(node)
if goodImages:
scoredImages = self.downloadImagesAndGetResults(
goodImages, parentDepthLevel)
if scoredImages:
highScoreImage = sorted(scoredImages.items(),
key=lambda x: x[1],
reverse=True)[0][0]
mainImage = Image()
mainImage.imageSrc = highScoreImage.imgSrc
mainImage.imageExtractionType = "bigimage"
mainImage.confidenceScore = 100 / len(scoredImages) \
if len(scoredImages) > 0 else 0
return mainImage
depthObj = self.getDepthLevel(node, parentDepthLevel,
siblingDepthLevel)
if depthObj:
return self.checkForLargeImages(depthObj.node,
depthObj.parentDepth,
depthObj.siblingDepth)
return None
def checkForKnownElements(self):
"""\
in here we check for known image contains from sites
we've checked out like yahoo, techcrunch, etc... that have
* known places to look for good images.
* TODO: enable this to use a series of settings files
so people can define what the image ids/classes
are on specific sites
"""
domain = self.getCleanDomain()
if domain in self.customSiteMapping.keys():
classes = self.customSiteMapping.get(domain).split('|')
for classname in classes:
KNOWN_IMG_DOM_NAMES.append(classname)
knownImage = None
for knownName in KNOWN_IMG_DOM_NAMES:
known = Parser.getElementById(self.article.rawDoc, knownName)
if not known:
known = Parser.getElementsByTag(self.article.rawDoc,
attr='class',
value=knownName)
if known:
known = known[0]
if known:
mainImage = Parser.getElementsByTag(known, tag='img')
if mainImage:
knownImage = mainImage[0]
if knownImage is not None:
knownImgSrc = Parser.getAttribute(knownImage, attr='src')
mainImage = Image()
mainImage.imageSrc = self.buildImagePath(knownImgSrc)
mainImage.imageExtractionType = "known"
mainImage.confidenceScore = 90
locallyStoredImage = self.getLocallyStoredImage(mainImage.imageSrc)
if locallyStoredImage:
mainImage.bytes = locallyStoredImage.bytes
mainImage.height = locallyStoredImage.height
mainImage.width = locallyStoredImage.width
return mainImage
def checkForKnownElements(self):
"""\
in here we check for known image contains from sites
we've checked out like yahoo, techcrunch, etc... that have
* known places to look for good images.
* TODO: enable this to use a series of settings files
so people can define what the image ids/classes
are on specific sites
"""
domain = self.getCleanDomain()
if domain in self.customSiteMapping.keys():
classes = self.customSiteMapping.get(domain).split('|')
for classname in classes:
KNOWN_IMG_DOM_NAMES.append(classname)
knownImage = None
for knownName in KNOWN_IMG_DOM_NAMES:
known = Parser.getElementById(self.article.rawDoc, knownName)
if not known:
known = Parser.getElementsByTag(self.article.rawDoc,
attr='class', value=knownName)
if known:
known = known[0]
if known:
mainImage = Parser.getElementsByTag(known, tag='img')
if mainImage:
knownImage = mainImage[0]
if knownImage is not None:
knownImgSrc = Parser.getAttribute(knownImage, attr='src')
mainImage = Image()
mainImage.imageSrc = self.buildImagePath(knownImgSrc)
mainImage.imageExtractionType = "known"
mainImage.confidenceScore = 90
locallyStoredImage = self.getLocallyStoredImage(mainImage.imageSrc)
if locallyStoredImage:
mainImage.bytes = locallyStoredImage.bytes
mainImage.height = locallyStoredImage.height
mainImage.width = locallyStoredImage.width
return mainImage
def checkForOpenGraphTag(self):
"""\
checks to see if we were able to
find open graph tags on this page
"""
node = self.article.rawDoc
meta = Parser.getElementsByTag(node, tag='meta', attr='property', value='og:image')
for item in meta:
href = Parser.getAttribute(item, attr='content')
if href:
mainImage = Image()
mainImage.imageSrc = href
mainImage.imageExtractionType = "opengraph"
mainImage.confidenceScore = 100
locallyStoredImage = self.getLocallyStoredImage(mainImage.imageSrc)
if locallyStoredImage:
mainImage.bytes = locallyStoredImage.bytes
mainImage.height = locallyStoredImage.height
mainImage.width = locallyStoredImage.width
return mainImage
return None
def checkForLinkTag(self):
"""\
checks to see if we were able to
find open link_src on this page
"""
node = self.article.rawDoc
meta = Parser.getElementsByTag(node, tag='link', attr='rel', value='image_src')
for item in meta:
href = Parser.getAttribute(item, attr='href')
if href:
mainImage = Image()
mainImage.imageSrc = href
mainImage.imageExtractionType = "linktag"
mainImage.confidenceScore = 100
locallyStoredImage = self.getLocallyStoredImage(mainImage.imageSrc)
if locallyStoredImage:
mainImage.bytes = locallyStoredImage.bytes
mainImage.height = locallyStoredImage.height
mainImage.width = locallyStoredImage.width
return mainImage
return None
