Work in progress tutorial for scraping streaming sites
``` -Now there's multiple ways to get the text, but the 2 methods I always use is Regex and CSS selectors. Regex is basically a ctrl+f on steroids, you can search for anything. CSS selectors is a way to parse the HTML like a browser and select an element in it. +Now there are multiple ways to get the text, but the 2 methods I always use are Regex and CSS selectors. Regex is a ctrl+f on steroids, you can search for anything. CSS selectors are a way to parse the HTML like a browser and select an element in it. ## CSS Selectors The element is a paragraph tag, eg ``, which can be found using the CSS selector: "p". -classes helps to narrow down the CSS selector search, in this case: `class="f4 mt-3"` +classes help to narrow down the CSS selector search, in this case: `class="f4 mt-3"` This can be represented with ```css @@ -104,12 +104,12 @@ This prints: NodeList [p.f4.mt-3] ``` -### **NOTE**: You may not get the same results when scraping from command line, classes and elements are sometimes created by javascript on the site. +### **NOTE**: You may not get the same results when scraping from the command line, classes and elements are sometimes created by javascript on the site. **Python** -```python +```Python import requests from bs4 import BeautifulSoup # Full documentation at https://www.crummy.com/software/BeautifulSoup/bs4/doc/ @@ -158,9 +158,9 @@ to get the whole site document as text and copy everything Paste it in the test string in regex101 and try to write an expression to only capture the text you want. -In this case the elements is +In this case, the elements are -```html +```HTML
Work in progress tutorial for scraping streaming sites
@@ -172,7 +172,7 @@ Maybe we can search for `` (backslashes for ")
``` -Gives a match, so lets expand the match to all characters between the two brackets ( p>........\s*(.*)?\s*<" # r"" stands for raw, which makes blackslashes work better, used for regexes +description_regex = r"
\s*(.*)?\s*<" # r"" stands for raw, which makes backslashes work better, used for regexes +description = re.search(description_regex, response.text).groups()[0] +print(description) +``` + +**Kotlin** +In main.kt +```kotlin +fun main() { + val url = "https://github.com/Blatzar/scraping-tutorial" + val response = khttp.get(url) + val descriptionRegex = Regex("""
Ctrl + Shift + I + +or + +f12 + +or + +Right-click and press *Inspect* + +Here you can look at all the network requests the browser is making and much more, but the important part currently is the HTML displayed. You need to find the HTML responsible for showing the project description, but how? + +Either click the small mouse in the top left of the developer tools or press + +Ctrl + Shift + C + +This makes your mouse highlight any element you hover over. Press the description to highlight the element responsible for showing it. + +Your HTML will now be focused on something like: + + +```HTML +
+ Work in progress tutorial for scraping streaming sites +
+``` + +Now there are multiple ways to get the text, but the 2 methods I always use are Regex and CSS selectors. Regex is a ctrl+f on steroids, you can search for anything. CSS selectors are a way to parse the HTML like a browser and select an element in it. + +## CSS Selectors + +The element is a paragraph tag, eg ``, which can be found using the CSS selector: "p". + +classes help to narrow down the CSS selector search, in this case: `class="f4 mt-3"` + +This can be represented with +```css +p.f4.mt-3 +``` +a dot for every class [full list of CSS selectors found here](https://www.w3schools.com/cssref/css_selectors.asp) + +You can test if this CSS selector works by opening the console tab and typing: + +```js +document.querySelectorAll("p.f4.mt-3"); +``` + +This prints: +```java +NodeList [p.f4.mt-3] +``` + +### **NOTE**: You may not get the same results when scraping from the command line, classes and elements are sometimes created by javascript on the site. + + +**Python** + +```Python +import requests +from bs4 import BeautifulSoup # Full documentation at https://www.crummy.com/software/BeautifulSoup/bs4/doc/ + +url = "https://github.com/Blatzar/scraping-tutorial" +response = requests.get(url) +soup = BeautifulSoup(response.text, 'lxml') +element = soup.select("p.f4.mt-3") # Using the CSS selector +print(element[0].text.strip()) # Selects the first element, gets the text and strips it (removes starting and ending spaces) +``` + +**Kotlin** + +In build.gradle: +```gradle +repositories { + mavenCentral() + jcenter() + maven { url 'https://jitpack.io' } +} + +dependencies { + // Other dependencies above + implementation "org.jsoup:jsoup:1.11.3" + compile group: 'khttp', name: 'khttp', version: '1.0.0' +} +``` +In main.kt +```kotlin +fun main() { + val url = "https://github.com/Blatzar/scraping-tutorial" + val response = khttp.get(url) + val soup = Jsoup.parse(response.text) + val element = soup.select("p.f4.mt-3") // Using the CSS selector + println(element.text().trim()) // Gets the text and strips it (removes starting and ending spaces) +} +``` + + +## **Regex:** + +When working with Regex I highly recommend using [regex101.com](https://regex101.com/) (using the python flavor) + +Press Ctrl + U + +to get the whole site document as text and copy everything + +Paste it in the test string in regex101 and try to write an expression to only capture the text you want. + +In this case, the elements are + +```HTML +
+ Work in progress tutorial for scraping streaming sites +
+``` + +Maybe we can search for `` (backslashes for ") + +```regex +
+``` + +Gives a match, so let's expand the match to all characters between the two brackets ( p>....\s*(.*)?\s*< +``` + +**Explained**: + +Any text exactly matching `
` +then any number of whitespaces +then any number of any characters (which will be stored in group 1) +then any number of whitespaces +then the text `<` + + +In code: + +**Python** + +```python +import requests +import re # regex + +url = "https://github.com/Blatzar/scraping-tutorial" +response = requests.get(url) +description_regex = r"
\s*(.*)?\s*<" # r"" stands for raw, which makes backslashes work better, used for regexes description = re.search(description_regex, response.text).groups()[0] print(description) ```