Open graph fully absolute urls support

[guiohm]

• Fixes the issue og:url incorrect when site is put under subdirectory #942
• Allows using fully absolute urls for og image tags (which is mandatory for Facebook).
• Fixes poor external link detection

I don't quite understand why the optional subdirectory had to be added on both config.urland config.root.
I believe this is more relevant now.

[leesei]

Are #942, #943 related?

The link for the sites title should be config.url + config.root (better use url.resolve() for url concatenation), can you verify that?

[guiohm]

This fixes #942 but not #943 (I might look into that later).

I don't see where is the site title link you're talking about?

My last commit adds url.resolve in 2 places, it should be done elsewhere but I think we should count on sanitized settings (and improve it) made when loading config: https://github.com/hexojs/hexo/blob/master/lib/loaders/config.js#L110-116

What do you think?

[guiohm]

In the meantime, I'm searching how to fix #943. I think that no code exist to handle rewriting all urls in a post, right?
The closest one I found is the filter for external links detection here: https://github.com/hexojs/hexo/blob/master/lib/plugins/filter/external_link.js

So do we want to add another filter for that? or adding it to the existing one?
We need to rewrite a tags and img tags as well by the way.

[If I do that, I'll open another pull request]

[leesei]

Thanks for your effort.
I agree that it's better to normalize the site's url in one place (config) rather than letting each plugin/theme to recompute it.

What I meant by the site url is:

• the link for "Home" and "jr0cket" in the header in http://jr0cket.co.uk/
• the link for the logo on http://hexo.io/
• however the "Home" and "Landscape" points to different urls in http://hexo.io/hexo-theme-landscape/

I'm not sure if the whole "child directory" feature was intended to implement the last use case, which is kind of link http://nodejs.org/ and http://nodejs.org/blog.

---

If links are not rewritten, that means this PR is a bugfix in Hexo internal and possibly relates to theme developers.
While the blog writer still need some tag for internal links (#458), otherwise the config.root and permalinks would be all over the .md files, rendering them un-portable. It would be a vast effort to change config.root or permalink format (whether they should be changed is another issue).

I brought the internal links issue up since these two issues both relates to the interpretation and use case of config.url and config.root.

[guiohm]

So I added the last piece of normalization of config.url and config.root at config load time.
I checked the site home/title url issue and no issue for me with this PR.

About the internal links in .md files, beside a helper that would obviously help. I believe we should really consider adding a filter to detect links to images or any other file already added manually or via other tag helpers.
For instance I'm adding images manually in my posts (located in source/images), so I should write this:
<img src="/images/cords-237x300.jpg" alt="attachment cords" class="image-left" />
But I need instead to put:
<img src="/blog/images/cords-237x300.jpg" alt="attachment cords" class="image-left" />

I believe that config.url and config.root are now setup to suit any use-case. So development should continue based on that.
I might very well write a filter to address my issue in the next few days, at least temporarily.

[guiohm]

Wooops, I mistakenly closed the PR....

[guiohm]

Hummm... The Travis build 504 (https://travis-ci.org/hexojs/hexo/builds/43772973) is locked currently. I suppose some admin needs to re-trigger the build?

[guiohm]

Well, the build timed out... I don't ses any restart button. Anyone?

[leesei]

As a site note (as I found in #943), if you enable config.relative_link,

<img src="images/cords-237x300.jpg" alt="attachment cords" class="image-left" />

note the absence of '/' prefix

the src url will take config.root into consideration. Please try it out.

[guiohm]

config.relative_link and not using '/' won't work because the post is displayed on multiple pages (post page, index, tags, archives, categories) and the url would need to be rewritten differently on each page.

Same issue If I activate post_asset_folder and if I put the image in the asset folder of the post.

The only way for me to make it work on all pages is to use non-relative urls in src tags and adding the config.root manually.

[Xuanwo]

The build was gone for so long that I can't rebuild it, make a new pr or commit may restart it.

[stale]

This issue has been automatically marked as stale because lack of recent activity. It will be closed if no further activity occurs. Thank you for your contributions.

[github-actions]

How to test

git clone -b open_graph_fully_absolute_urls_support https://github.com/guiohm/hexo.git
cd hexo
npm install
npm test

[stevenjoezhang]

Superseded by #4616
root option is now optional