Warc2graph extracts a graph data structure from WARC files. The module was built to dig deeper into WARC files. It extracts (almost) all internal and external references from a WARC file by analyzing the WARC header and the payload. Multiple methods can be used for extraction, single or combined. Warc2graph has a CLI interface and can be used as a python module. The output when using the CLI interface consists of graph data in a standard graph XML format GEXF and several visualizations of that data using different visualization algorithms. We acknowledge that visualizations carry an epistemic value and thus need to be designed according to the analyzed objects and research questions. Warc2graph uses NetworkX as its graph data and analytics backend, so more involved graph data analytics can be realized when using warc2graph as a python module.

The initial purpose of warc2graph was to analyze and visualize the textual structure of net literature works in the DLA corpus of net literature works and blogs dating from the early time of the web in the 1990s up to the 2000s. Development is part of the Science Data Center for Literature research project. We now consider warc2graph as a tool for detailed WARC analytics regarding the referential structure of the archived sites and hope that it will be useful for the web archiving and web research community.

Warc2graph is under active development.

If you consider using warc2graph for a research project or in an archival context, please get in touch! We'd love to hear about your work.

Warc2graph has been presented at the Electronic Literature Organization Conference 2020:
| Overview and Video: https://elmcip.net/critical-writing/networks-net-literature-modelling-extracting-and-visualizing-link-based-networks | Conference Paper (PDF): https://elmcip.net/sites/default/files/media/critical_writing/attachments/claus-michael_schlesinger_mona_ulrich_pascal_hein_and_andre_blessing_networks_of_net_literature_-_modelling_extracting_and_visualizing_192.pdf

warc2graph requires Python >= 3.6.

Use the package manager pip to install warc2graph.

pip install warc2graph

Alternatively you can install manually using the python package setuptools.

git clone https://github.com/dla-marbach/warc2graph.git
cd warc2graph
python3 setup.py build
python3 setup.py install --user

To be able to use the dot algorithm to visualize the graph, make sure, to have GraphViz installed.

You can use the package in your python projects, or you can use the provided command line interface. While the former offers more possibilities, the latter might be more intuitive.

The installation of the package provides the warc2graph command for your terminal. Call warc2graph --help to get an overview over the available options.

If you want to create a model for only one warc file simply call

warc2graph path/to/warc.warc.gz

If the warc file is not on you file system, and you want it to be downloaded from the internet, you can pass an url. You have to pass the parameter d.

warc2graph url/to/warc.warc.gz d

If you want to create a model using a list of warc files all together archiving one big website, first create a list of all the warc files.

ls path/to/warcs/*.warc.gz >> list_of_warcs.txt

You can also create the file manually, it should look as follows.

path/to/warc1.warc.gz
path/to/warc2.warc.gz
path/to/warc3.warc.gz
path/to/warc4.warc.gz

Then call warc2graph with the parameter wl, and the list as an input file.

warc2graph list_of_warcs.txt wl

You can also model a website that is not archived. Create a plain text file containing the urls to all the webpages you want to consider. This file should look as follows.

url/to/webpage1.html
url/to/webpage2.htm

Then call warc2graph with the parameter ll, and the list as an input file.

warc2graph list_of_webpages.txt ll

• methods to use
• create visualisation
• blacklist

You can inspect the examples.ipynb using jupyter notebook for some interactive examples.

Our package relies heavily on the networkx package. Read its documentation for further information about the possibilities and interfaces for the analysis of networkx graphs.

import warc2graph  # our package
import matplotlib.pyplot as plt  # plot graphs
import networkx as nx  # handle graphs

# assign the path to a warc file to a variable
warc_path = "tests/WEB-20210202165627638-00000-24143~clarin02~8443.warc.gz"

# create a basic model with all resources as nodes and all links and embeddings as edges
basic_model = warc2graph.create_graph(warc_path)

# visualizing the graph using the graphviz "dot" algorithm
fig, ax = plt.subplots(1, figsize=(8, 4))
pos = nx.drawing.nx_agraph.graphviz_layout(basic_model, prog="dot")
nx.draw_networkx(basic_model, with_labels=False, pos=pos, ax=ax)
plt.draw()

import warc2graph  # our package
import networkx as nx  # handle graphs
from pprint import PrettyPrinter  # print dicts nicely

pp = PrettyPrinter()

warc_path = "tests/WEB-20210202165627638-00000-24143~clarin02~8443.warc.gz"
basic_model = warc2graph.create_graph(warc_path)
degree_centralities = nx.algorithms.centrality.degree_centrality(basic_model)

pp.pprint(degree_centralities)

Outputs:

{'https://httpd.apache.org/': 0.07692307692307693,
 'https://www.scientificlinux.org/': 0.07692307692307693,
 'https://clarin09.ims.uni-stuttgart.de/': 0.23076923076923078,
 'https://clarin09.ims.uni-stuttgart.de/icons/apache_pb2.gif': 0.07692307692307693,
 'https://clarin09.ims.uni-stuttgart.de/sdc_warc/angular1.html': 0.23076923076923078,
 'https://clarin09.ims.uni-stuttgart.de/sdc_warc/index.html': 0.8461538461538463,
 'https://clarin09.ims.uni-stuttgart.de/sdc_warc/jquery.html': 0.23076923076923078,
 'https://clarin09.ims.uni-stuttgart.de/sdc_warc/js/angular.min.js': 0.07692307692307693,
 'https://clarin09.ims.uni-stuttgart.de/sdc_warc/js/jquery-1.11.3.min.js': 0.07692307692307693,
 'https://clarin09.ims.uni-stuttgart.de/sdc_warc/page1.html': 0.15384615384615385,
 'https://clarin09.ims.uni-stuttgart.de/sdc_warc/page2.html': 0.15384615384615385,
 'https://clarin09.ims.uni-stuttgart.de/sdc_warc/page_target_ang1.html': 0.07692307692307693,
 'https://clarin09.ims.uni-stuttgart.de/sdc_warc/page_target_jquery1.html': 0.07692307692307693,
 'https://clarin09.ims.uni-stuttgart.de/sdc_warc/page_target_jquery2.html': 0.07692307692307693}

You can also enrich the models using the original data.

import warc2graph  # our package

# assign the path to a warc file to a variable
warc_path = "tests/WEB-20210202165627638-00000-24143~clarin02~8443.warc.gz"

# create an enriched model, structured like the basic model but containing the html content and counts of all tags
enriched_model = warc2graph.create_graph(warc_path, include_content=True, count_tags=True)

index_node = "https://clarin09.ims.uni-stuttgart.de/sdc_warc/index.html"
print(enriched_model.nodes[index_node]["counted_tags"])
# prints:
# {'html': 1, 'head': 1, 'meta': 1, 'title': 1, 'body': 1, 'a': 4, 'br': 6}

print(enriched_model.nodes[index_node]["content"])

Prints:

<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8">
<title>Insert title here</title>
</head>
<body>

<a href="page1.html">page1</a>

<br>
<br>
<a href="page2.html">page2</a>

<br>
<br>
<a href="angular1.html">angular1</a>


<br>
<br>
<a href="jquery.html">jquery</a>

</body>
</html>

Pull requests are welcome. For major changes, please open an issue first to discuss what you would like to change.

Please make sure to update tests as appropriate.

All contributed Code will be licensed under the GNU Lesser General Public License.

By contributing you accept the following terms and conditions:

• You grant the rights for your contribution to be used, distributed and modified together with warc2graph and under the same license.
• Your contribution consists of your work, no third party holds rights over it.
• You grant us the right to redistribute the software including your contribution under a different (permissive or non-permissive) open source license.

warc2graph is free software: you can redistribute it and/or modify it under the terms of the GNU Lesser General Public License as published by the Free Software Foundation, either version 3 of the License, or (at your option) any later version.

warc2graph is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License for more details.

You should have received a copy of the GNU Lesser General Public License along with warc2graph. If not, see https://www.gnu.org/licenses/lgpl-3.0.html.

Consider COPYING and COPYING.LGPL.

warc2graph makes heavy and critical use of following open source libraries:

• BeautifulSoup
• matplotlib
• NetworkX
• Selenium
• Setuptools
• Warcio
• webdriver-manager
• trafilatura