Add blog post "Demystifying Gaia-X Credentials"

[markus-hentsch]

No description provided.

[markus-hentsch]

@martinmo can you try the local preview instructions at #952 (comment) and check if you can review the PR using this method?

[markus-hentsch]

Note to self: I learned some new things about VC subject IDs here: SovereignCloudStack/gx-credential-generator#70 (comment)

I'll need to update the blog post draft:

• emphasize that VC IDs need to be unique as per https://docs.gaia-x.eu/technical-committee/identity-credential-access-management/22.10/credential_format/#identifiers
• emphasize that in the VP, the Participant VC's legalRegistrationNumber reference ID must match the subject ID of the LRN VC in the same document
• rephrase the part that states that the LRN VC ID must be the hosted URL to the VC JSON (it does not seem to be the case after all)

[markus-hentsch]

Note to self: I learned some new things about VC subject IDs here: SovereignCloudStack/gx-credential-generator#70 (comment)

I'll need to update the blog post draft:

* [x]  emphasize that VC IDs need to be unique as per https://docs.gaia-x.eu/technical-committee/identity-credential-access-management/22.10/credential_format/#identifiers

* [x]  emphasize that in the VP, the Participant VC's legalRegistrationNumber reference ID must match the subject ID of the LRN VC in the same document

* [x]  rephrase the part that states that the LRN VC ID must be the hosted URL to the VC JSON (it does not seem to be the case after all)

After concluding my research on the identifier topic, I added two new figures and corresponding paragraphs to explain the identifier relations, restrictions and possible approaches.

[martinmo]

@martinmo can you try the local preview instructions at #952 (comment) and check if you can review the PR using this method?

It doesn't work for me – when I run

bundle exec jekyll serve config _config.yml,_config.dev.yml  --incremental -H 0.0.0.0

in the scs-website container, I get a Liquid Exception:

  Liquid Exception: wrong number of arguments (given 1, expected 0; required keywords: type, args) in /site/_layouts/post.html
                    ------------------------------------------------
      Jekyll 4.3.3   Please append `--trace` to the `serve` command 
                     for any additional information or backtrace. 
                    ------------------------------------------------
/site/_gems/jekyll-assets/lib/jekyll/assets/extensible.rb:107:in `for?': wrong number of arguments (given 1, expected 0; required keywords: type, args) (ArgumentError)
	from /site/_gems/jekyll-assets/lib/jekyll/assets/proxy.rb:55:in `block in proxies_for'
	from /site/_gems/jekyll-assets/lib/jekyll/assets/proxy.rb:54:in `select'
	from /site/_gems/jekyll-assets/lib/jekyll/assets/proxy.rb:54:in `proxies_for'
	from /site/_gems/jekyll-assets/lib/jekyll/assets/proxy.rb:29:in `proxy'
	from /site/_gems/jekyll-assets/lib/jekyll/assets/tag.rb:198:in `internal'
	from /site/_gems/jekyll-assets/lib/jekyll/assets/tag.rb:66:in `render_raw'
	from /site/_gems/jekyll-assets/lib/jekyll/assets/tag.rb:82:in `render'
	from /usr/local/bundle/gems/liquid-4.0.4/lib/liquid/block_body.rb:103:in `render_node_to_output'
	from /usr/local/bundle/gems/liquid-4.0.4/lib/liquid/block_body.rb:91:in `render'
        ...

But I was able to follow a tip by Matthias and deployed your blog post on the staging website: https://staging.scs.community/website/2024/06/05/demystifying-gaia-x-credentials/. Here's a screenshot of the steps which achieve this:

[martinmo]

This is very well written and makes a complex topic accessible. I especially like how the use case is exercised step by step. Together with the nice graphics I was able to follow and understand.

Content-wise I don't have any complaints at all and I couldn't find typos or grammar issues. I only have two very minor suggestions which you may consider but in any case I already approve.

PS. Before merging, don't forget to rename the file name (and refresh+rename symlink from the _i18n/de folder) to update the publish date, which is still at 2024-06-05.

[markus-hentsch]

@martinmo thanks for your review! Based on your feedback I did some adjustments: d974bb1...6b4f0b0

I redeployed at: https://staging.scs.community/website/2024/06/05/demystifying-gaia-x-credentials/

I'll update the date once we make the final publishing decision (especially regarding the ongoing work on the scs-did-creator and gx-credential-generator tools).