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{{Project
|Has project output=Tool
|Has sponsor=Kauffman Incubator Project
|Has title=Listing Page Classifier
|Has owner=Nancy Yu,
==Current Work==
[[Listing Page Classifier Progress|Progress Log (updated on 45/2217/2019)]]
===Main Tasks===
# Build a site map generator: output every internal link of a website
# Build a tool that captures screenshots of individual web pages
# Build a CNN classifier using Python and TensorFlow
===Site Map Generator===
====URL Extraction from HTML====
The goal here is to identify url links from the HTML code of a website. We can solve this by finding the place holder, which is the anchor tag <a>, for a hyperlink. Within the anchor tag, we may locate the href attribute that contains the url that we look for (see example below). <code><a href="/wiki/Listing_Page_Classifier_Progress" title="Listing Page Classifier Progress"> Progress Log (updated on 4/15/2019)</a></code>
Issues may occur:
* If the href is not presented in a full url format (referring to the example above), then it is for sure an internal link
* If the href is in a full url format, but it does not contain the domain name, then it is an external link (see example below, assuming the domain name is not facebook.com)
<code><a href = https://www.facebook.com/...></a></code>
====Algorithm on Collecting Internal Links====
[[File:WebPageTree.png|700px500px|thumb|center|Site Map Tree]]
Intuition'''Intuitions:'''
*We treat each internal page as a tree node
*Each node can have multiple linked children or none
*Taking the above picture as an example, the homepage is the first tree node (at depth = 0) that we will be given as an input to our function, and it has 4 children (at depth = 1): page 1, page 2, page 3, and page 4
*Given the above idea, we have built 2 following algorithms to find all internal links of a web page with 2 user inputs: homepage url and depth
 
'''Note:''' the '''recommended maximum depth''' input is '''2'''. Since our primary goal is to capture the screenshot of the portfolio page (client listing page) and this page often appears at the first depth, if not, second depth will be enough to achieve the goal, no need to dive deeper than the second depth.
'''''Breadth-First Search (BFS) approach''''':
We examine all pages(nodes) at the same depth before going down to the next depth.
 
Python file saved in
E:\projects\listing page identifier\Internal_Link\Internal_url_BFS.py'''''Depth-First Search (DFS) approach''''':
We visit ===Web Page Screenshot Tool===This tool reads two text files: test.txt and train.txt, and outputs a pagefull screenshot (node) "A" and then all A's children see sample output on the current path will be visited before we visit A's neighbor node "B"right) of each url in these 2 text files.[[File:screenshotEx.png|200x400px|thumb|right|Sample Output]]
For example====Browser Automation Tool====The initial idea was to use the [https://www.seleniumhq.org/ selenium] package to set up a browser window that fits the web page size, assuming then capture the furthest depth whole window to get a user wants to dig in is 2full screenshot of the page. After several test runs on different websites, we will start this method worked great for most web pages but with some exceptions. Therefore, the [https://splinter.readthedocs.io/en/latest/why.html splinter] package is chosen as the final browser automation tool to assist our homepage and then examine its first child node "page 1", then visiting page 1's children until we meet screenshot tool  ====Used Browser====The picked browser for taking screenshot is Firefox. A geckodriver v0.24.0 was downloaded for setting up the maximum depthbrowser during browser automation. Then we move onto homepage '''Note:''s second child "page 2" and visit page 2's children until we reach initial plan was to use Chrome, but encountered some issues with switching different versions(v73 to v74) of chromedriver during the maximum depth. Next we visit homepage's next child and so onbrowser automation.
Python file saved in
E:\projects\listing page identifier\screen_shot_tool.py
 
===Image Processing===
This method would likely rely on a [https://en.wikipedia.org/wiki/Convolutional_neural_network convolutional neural network (CNN)] to classify HTML elements present in web page screenshots. Implementation could be achieved by combining the VGG16 model or ResNet architecture with batch normalization to increase accuracy in this context.
====Set Up====
*Possible Python packages for building CNN: TensorFlow, PyTorch, scikit
*Current dataset: <code>The File to Rule Them All</code>, contains information of 160 accelerators (homepage url, found cohort url etc.)
** We will use the data of 121 accelerators, which have cohort urls found, for training and testing our CNN algorithm
** After applying the above Site Map Generator to those 121 accelerators, we will use 75% of the result data to train our model. The rest, 25% will be used as the test data
*The type of inputs for training CNN model:
#Image: picture of the web page (generated by the Screenshot Tool)
#Class Label: Cohort indicator ( 1 - it is a cohort page, 0 - not a cohort page)
 
====Data Preprocessing====
'''''Retrieving All Internal Links: ''''' this <code>generate_dataset.py</code> reads all homepage urls in the file <code>The File to Rule Them All.csv</code> and then feed them into the Site Map Generator to retrieve their corresponding internal urls
*This process assigns corresponding cohort indicator to each url, which is separated by tab (see example below)
http://fledge.co/blog/ 0
http://fledge.co/fledglings/ 1
http://fledge.co/2019/visiting-malawi/ 0
http://fledge.co/about/details/ 0
http://fledge.co/about/ 0
 
*Results are automatically split into two text files: <code>train.txt</code> and <code>test.txt</code>.
Python file saved in E:\projects\listing page identifier\Internal_Link\Internal_url_DFSgenerate_dataset.py
===Web Page '''''Generate and Label Image Data: ''''' feed paths/directories of <code>train.txt</code> and <code>text.txt</code> into Screenshot Tool (IN PROGRESS)===to get our image dataThis tool will take 2 user input*Results are split into two folders: the url train and the output file(.png)'s name. It will output a png file that has the full screen shot of a web page (see output file example on the right)test** Also separated into sub-folders: cohort and not_cohort[[File:screenshotExautoName.png|50px|thumb|right|Sample Output250px]]** Make sure to create train and test folders (in the '''same directory''' as <code>train.txt</code> and <code>text.txt</code>), and their sub-folders cohort and not_cohort '''BEFORE''' running the Screenshot Tool
====CNN Model====
Python file saved in
E:\projects\listing page identifier\screen_shot\screen_shot_toolcnn.py
'''''NOTE: '''''[https://keras.io/ Keras] package (with TensorFlow backend) is used for setting up the model '''Current condition/issue''' of the model:* loss: 0.9109, accuracy: 0.9428* The model runs with no problem, however, it does not make classification. All predictions on the test set are the same Some '''factors/problems''' to consider for '''future implementation''' on the model:* Class label is highly imbalanced: o (not cohort) is way more than 1 (cohort) class**may cause our model favoring the larger class, then the accuracy metric is not reliable**several suggestions to fix this: A) under-sampling the larger class B)over-sampling the smaller class* Convert image data into same format: [https://www.oreilly.com/library/view/linux-multimedia-hacks/0596100760/ch01s04.html Make image thumbnail]**we can modify image target size in our CNN, but we don't know if Keras library crop or re-scale image with given target size*I chose to group images into cohort folder or not_cohort folder to let our CNN model detect the class label of an image. There are certainly other ways to detect class label and one may want to modify the Screenshot Tool and <code>cnn.py</code> to assist with other approaches  Useful rescource:*Image generator in Keras: https://keras.io/preprocessing/image/*Keras tutorial for builindg a CNN: https://adventuresinmachinelearning.com/keras-tutorial-cnn-11-lines/ https://towardsdatascience.com/building-a-convolutional-neural-network-cnn-in-keras-329fbbadc5f5 https://becominghuman.ai/building-an-image-classifier-using-deep-learning-in-python-totally-from-a-beginners-perspective-be8dbaf22dd8 ===Image ProcessingWorkflow===This section summarizes a general process of utilizing above tools to get appropriate input for our CNN model, also serves as a guidance for anyone who wants to implement upon those tools.
This method would likely rely on a [https:# Feed raw data (as for now, our raw data is the <code>The File to Rule Them All.csv</code>) into <code> generate_dataset.py</encode> to get text files (<code>train.wikipediatxt</code> and<code>text.orgtxt</wiki/Convolutional_neural_network convolutional neural network code>) that contain a list of all internal urls with their corresponding indicator (CNNclass label)] to classify HTML elements present # Create 2 folders: train and test, located in web page screenshotsthe same directory as <code>train. Implementation could be achieved by combining txt</code> and <code>text.txt</code>, also create 2 sub-folders: cohort and not_cohort within these 2 folders# Feed the VGG16 model or ResNet architecture with batch normalization to increase accuracy directory/path of <code>train.txt</code> and <code>text.txt</code> into <code>screen_shot_tool.py</code>. This process will automatically group images into their corresponding folders that we just created in this context.step 2

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