Skip to main content

OCaml RSS Feed Parser

Using Cameleon RSS Feed Parser

Looking for a way to parse RSS (or ATOM) feeds with OCaml, I performed a Google search on "ocaml rss":

Here is how to begin to use it...

Installing on Ubuntu/Debian

I assume the user has all de basic OCaml installation. Installing the RSS feed parser requires:

     sudo apt-get install libcameleon-ocaml-dev cameleon

Getting a sample RSS file

Let's get the RSS2 file of OCamlCore:

     wget http://planet.ocamlcore.org/rss20.xml
The file is saved as "rss20.xml" use the -O option of wget if you want another saving name.

Using it in the toplevel

The user needs to load several modules:

        Objective Caml version 3.11.2       #use "topfind"                  ;;     #require "unix"                 ;;     #require "cameleon"             ;;     #require "cameleon.config_file" ;;     #require "cameleon.configwin"   ;;     #require "cameleon.ffind"       ;;     #require "cameleon.gdir"        ;;     #require "cameleon.gmylist"     ;;     #require "cameleon.gstuff"      ;;     #require "cameleon.okey"        ;;     #require "cameleon.report"      ;;     #load "/usr/lib/ocaml/cameleon/rss.cma";;
Load the XML RSS file (Pretty Long output) 
     let my_channel = Rss.channel_of_file "rss20.xml";;
Get the list of items (Pretty Long output) 
     let items = my_channel.Rss.ch_items);;
Grab the first item 
     List.hd items;;
Get the title of that first item 
     (List.hd items).Rss.item_title;;

Note

Please note that it is a quick and dirty way to do it, the reader is encouraged to suggest cleaner ways by commenting this post.

Popular posts from this blog

npm run build base-href

Using NPM to specify base-href When building an Angular application, people usually use "ng" and pass arguments to that invocation. Typically, when wanting to hard code "base-href" in "index.html", one will issue: ng build --base-href='https://ngx.rktmb.org/foo' I used to build my angular apps through Bamboo or Jenkins and they have a "npm" plugin. I got the habit to build the application with "npm run build" before deploying it. But the development team once asked me to set the "--base-href='https://ngx.rktmb.org/foo'" parameter. npm run build --base-href='https://ngx.rktmb.org/foo did not set the base href in indext.html After looking for a while, I found https://github.com/angular/angular-cli/issues/13560 where it says: You need to use −− to pass arguments to npm scripts. This did the job! The command to issue is then: npm run build -- --base-href='https://ngx.rktmb.org/foo&
Read more

Jenkins invalid privatekey

Publish over SSH, Message "invalid privatekey:" With quite recent (June-July 2020) installations of Jenkins and OpenSSH, I have the following error message when using the "Deploy overs SSH" Jenkins plug-in and publishing artifacts to the target overs SSH: jenkins.plugins.publish_over.BapPublisherException: Failed to add SSH key. Message [invalid privatekey: [B@d8d395a] This problem seems to be referenced here: https://issues.jenkins-ci.org/browse/JENKINS-57495 Just regenerate a key with the right parameters To solve it: ssh-keygen -t rsa -b 4096 Or ssh-keygen -t rsa -b 4096 -m PEM
Read more

AzureCLI Custom Python

Installing Azure CLI on Archlinux When trying to install Azure CLI on Archlinux, I follow the documentation, in the "script" tab , and it leads to the following errors: [mihamina@arch-00 ~]$ curl -L https://aka.ms/InstallAzureCli | bash [...] Running install script. -- Verifying Python version. -- Python version 3.11.3 okay. [...] -- Executing: ['/usr/bin/python3', 'virtualenv.py', '--python', '/usr/bin/python3', '/home/mihamina/lib/azure-cli'] /tmp/tmpn0w4l6w9/virtualenv-16.7.11/virtualenv.py:24: DeprecationWarning: The distutils package is deprecated and slated for removal in Python 3.12. Use setuptools or check PEP 632 for potential alternatives import distutils.spawn /tmp/tmpn0w4l6w9/virtualenv-16.7.11/virtualenv.py:25: DeprecationWarning: The distutils.sysconfig module is deprecated, use sysconfig instead import distutils.sysconfig Already using interpreter /u
Read more