The repository consists of a command-line utility wayback-machine-scraper that can be used to scrape or download website data as it appears in archive.org's Wayback Machine.
It crawls through historical snapshots of a website and saves the snapshots to disk.
This can be useful when you're trying to scrape a site that has scraping measures that make direct scraping impossible or prohibitively slow.
It's also useful if you want to scrape a website as it appeared at some point in the past or to scrape information that changes over time.
The command-line utility is highly configurable in terms of what it scrapes but it only saves the unparsed content of the pages on the site.
If you're interested in parsing data from the pages that are crawled then you might want to check out scrapy-wayback-machine instead.
It's a downloader middleware that handles all of the tricky parts and passes normal response objects to your Scrapy spiders with archive timestamp information attached.
The middleware is very unobtrusive and should work seamlessly with existing Scrapy middlewares, extensions, and spiders.
It's what wayback-machine-scraper uses behind the scenes and it offers more flexibility for advanced use cases.
The package can be installed using pip.
pip install wayback-machine-scraperWriting a custom Scrapy spider and using the WaybackMachine middleware is the preferred way to use this project, but a command line interface for basic mirroring is also included.
The usage information can be printed by running wayback-machine-scraper -h.
usage: wayback-machine-scraper [-h] [-o DIRECTORY] [-f TIMESTAMP]
[-t TIMESTAMP] [-a REGEX] [-d REGEX]
[-c CONCURRENCY] [-u] [-v]
DOMAIN [DOMAIN ...]
Mirror all Wayback Machine snapshots of one or more domains within a specified
time range.
positional arguments:
DOMAIN Specify the domain(s) to scrape. Can also be a full
URL to specify starting points for the crawler.
optional arguments:
-h, --help show this help message and exit
-o DIRECTORY, --output DIRECTORY
Specify the domain(s) to scrape. Can also be a full
URL to specify starting points for the crawler.
(default: website)
-f TIMESTAMP, --from TIMESTAMP
The timestamp for the beginning of the range to
scrape. Can either be YYYYmmdd, YYYYmmddHHMMSS, or a
Unix timestamp. (default: 10000101)
-t TIMESTAMP, --to TIMESTAMP
The timestamp for the end of the range to scrape. Use
the same timestamp as `--from` to specify a single
point in time. (default: 30000101)
-a REGEX, --allow REGEX
A regular expression that all scraped URLs must match.
(default: ())
-d REGEX, --deny REGEX
A regular expression to exclude matched URLs.
(default: ())
-c CONCURRENCY, --concurrency CONCURRENCY
Target concurrency for crawl requests.The crawl rate
will be automatically adjusted to match this
target.Use values less than 1 to be polite and higher
values to scrape more quickly. (default: 10.0)
-u, --unix Save snapshots as `UNIX_TIMESTAMP.snapshot` instead of
the default `YYYYmmddHHMMSS.snapshot`. (default:
False)
-v, --verbose Turn on debug logging. (default: False)
The usage can be perhaps be made more clear with a couple of concrete examples.
One of the key advantages of wayback-machine-scraper over other projects, such as wayback-machine-downloader, is that it offers the capability to download all available archive.org snapshots.
This can be extremely useful if you're interested in analyzing how pages change over time.
For example, say that you would like to analyze many snapshots of the Hacker News front page as I did writing Reverse Engineering the Hacker News Algorithm. This can be done by running
wayback-machine-scraper -a 'news.ycombinator.com$' news.ycombinator.comwhere the --allow regular expression news.ycombinator.com$ limits the crawl to the front page.
This produces a file structure of
website/
└── news.ycombinator.com
├── 20070221033032.snapshot
├── 20070226001637.snapshot
├── 20070405032412.snapshot
├── 20070405175109.snapshot
├── 20070406195336.snapshot
├── 20070601184317.snapshot
├── 20070629033202.snapshot
├── 20070630222527.snapshot
├── 20070630222818.snapshot
└── etc.
with each snapshot file containing the full HTML body of the front page.
A series of snapshots for any page can be obtained in this way as long as suitable regular expressions and start URLs are constructed. If we are interested in a page other than the homepage then we should use it as the start URL instead. To get all of the snapshots for a specific story we could run
wayback-machine-scraper -a 'id=13857086$' 'news.ycombinator.com/item?id=13857086'which produces
website/
└── news.ycombinator.com
└── item?id=13857086
├── 20170313225853.snapshot
├── 20170313231755.snapshot
├── 20170314043150.snapshot
├── 20170314165633.snapshot
└── 20170320205604.snapshot
If the goal is to take a snapshot of an entire site at once then this can also be easily achieved.
Specifying both the --from and --to options as the same point in time will assure that only one snapshot is saved for each URL.
Running
wayback-machine-scraper -f 20080623 -t 20080623 news.ycombinator.com
produces a file structure of
website
└── news.ycombinator.com
├── 20080621143814.snapshot
├── item?id=221868
│ └── 20080622151531.snapshot
├── item?id=222157
│ └── 20080622151822.snapshot
├── item?id=222341
│ └── 20080620221102.snapshot
└── etc.
with a single snapshot for each page in the crawl as it appeared on June 23, 2008.