#scraping #web-scraping #regex #css-selectors #utility #twilio

app lookout

👀 Declarative, asynchronous scraper utility

2 releases

0.1.1 Feb 22, 2021
0.1.0 Feb 12, 2021

#10 in #twilio

MIT license

760KB
285 lines

Lookout

An asynchronous scraper utility. Given a TOML file describing sites, selectors, regex, and expected regex matches, this will continuously scrape and call/text your phone using Twilio when expected matches are not met (if configured).

For example, this could scrape for product stock and call you when the expected 'out of stock' elements on the page are no longer found.

lookout screenshot

Installation

cargo install lookout

Usage

By default, lookout will load lookout.toml from the directory from which it is run.

lookout

You can optionally pass a single argument specifying a path to the config file.

lookout ~/my-lookout.toml

If you are deploying on a server and would like to print logs, set the environment variable RUST_LOG=lookout.

RUST_LOG=lookout lookout

In order to debug the scrapers, turn on log in the configuration and run with RUST_LOG=lookout.

DISCLAIMER: Always abide by limits/regulations when scraping. The example below is for illustrative purposes only.

Example

log = false

# in seconds
error_delay = 300 # timeout 5 minutes after error
alert_delay = 300 # timeout 5 minutes after an alert

# upper bound on errors to prevent unbounded retries
allowed_errors = 20 

# twilio configuration
[twilio]
enable_call = true
enable_text = true
id = "XXXXXXXXXXXXXXXX"
auth = "XXXXXXXXXXXXXXXX"
to_phone = "+10123456789"
from_phone = "+10123456789"
default_callback = "https://<callback-url>"

# define a [[lookout]] block for each scraper
# required:
# - name
# - url
# - regex to search for
# - number of expected matches
# - timeout after each request
# optional:
# - list of selectors which will be used to filter the html
# - headers (see below)
[[lookout]]
name = "newegg"
url = "https://www.newegg.com/product"
regex = "OUT OF STOCK|SOLD OUT|Sold Out"
expected_matches = 3
selectors = [ "#app > div.page-content > div.page-section > div > div > div.row-side > div.product-buy-box",
              "#app > div.page-content > div.page-section > div > div > div.row-body > div.product-main.display-flex > div" ]
timeout = 180

[[lookout]]
name = "b&h"
url = "https://www.bhphotovideo.com/some/cool/product"
regex = "Notify When Available"
expected_matches = 1
timeout = 180

[[lookout]]
name = "bestbuy"
url = "https://www.bestbuy.com/site/something/"
regex = "Sold Out"
expected_matches = 2
timeout = 180

# optionally, add custom request headers for the scraper above
[lookout.headers]
"User-Agent" = "Wget/1.20.1 (linux-gnu)"
"Accept-Encoding" = "identity"
"ACCEPT" = "*/*"
"Connection" = "Keep-Alive"

Dependencies

~24–39MB
~607K SLoC