Add a BlackFriday option for rel="nofollow" on external links

Add a configuration option "nofollowLinks". When set to "true" the "HTML_NOFOLLOW_LINKS" flag is being passed to Blackfriday. Thereby all *absolute* links will get a "nofollow" value for the "rel" attribute.

Fixes #4722
This commit is contained in:
Stefan Neuhaus 2018-05-27 23:14:34 +02:00 committed by Bjørn Erik Pedersen
parent d68367cbe7
commit 7a6192647a
3 changed files with 13 additions and 0 deletions

View file

@ -43,6 +43,11 @@
Blackfriday flag: **`HTML_HREF_TARGET_BLANK`** <br> Blackfriday flag: **`HTML_HREF_TARGET_BLANK`** <br>
Purpose: `true` opens <s>external links</s> **absolute** links in a new window or tab. While the `target="_blank"` attribute is typically used for external links, Blackfriday does that for _all_ absolute links ([ref](https://discourse.gohugo.io/t/internal-links-in-same-tab-external-links-in-new-tab/11048/8)). One needs to make note of this if they use absolute links throughout, for internal links too (for example, by setting `canonifyURLs` to `true` or via `absURL`). Purpose: `true` opens <s>external links</s> **absolute** links in a new window or tab. While the `target="_blank"` attribute is typically used for external links, Blackfriday does that for _all_ absolute links ([ref](https://discourse.gohugo.io/t/internal-links-in-same-tab-external-links-in-new-tab/11048/8)). One needs to make note of this if they use absolute links throughout, for internal links too (for example, by setting `canonifyURLs` to `true` or via `absURL`).
`nofollowLinks`
: default: **`false`** <br>
Blackfriday flag: **`HTML_NOFOLLOW_LINKS`** <br>
Purpose: `true` creates <s>external links</s> **absolute** links with `nofollow` being added to their `rel` attribute. Thereby crawlers are advised to not follow the link. While the `rel="nofollow"` attribute is typically used for external links, Blackfriday does that for _all_ absolute links. One needs to make note of this if they use absolute links throughout, for internal links too (for example, by setting `canonifyURLs` to `true` or via `absURL`).
`plainIDAnchors` `plainIDAnchors`
: default **`true`** <br> : default **`true`** <br>
Blackfriday flag: **`FootnoteAnchorPrefix` and `HeaderIDSuffix`** <br> Blackfriday flag: **`FootnoteAnchorPrefix` and `HeaderIDSuffix`** <br>

View file

@ -108,6 +108,7 @@ type BlackFriday struct {
AngledQuotes bool AngledQuotes bool
Fractions bool Fractions bool
HrefTargetBlank bool HrefTargetBlank bool
NofollowLinks bool
SmartDashes bool SmartDashes bool
LatexDashes bool LatexDashes bool
TaskLists bool TaskLists bool
@ -124,6 +125,7 @@ func newBlackfriday(config map[string]interface{}) *BlackFriday {
"smartypantsQuotesNBSP": false, "smartypantsQuotesNBSP": false,
"fractions": true, "fractions": true,
"hrefTargetBlank": false, "hrefTargetBlank": false,
"nofollowLinks": false,
"smartDashes": true, "smartDashes": true,
"latexDashes": true, "latexDashes": true,
"plainIDAnchors": true, "plainIDAnchors": true,
@ -277,6 +279,10 @@ func (c *ContentSpec) getHTMLRenderer(defaultFlags int, ctx *RenderingContext) b
htmlFlags |= blackfriday.HTML_HREF_TARGET_BLANK htmlFlags |= blackfriday.HTML_HREF_TARGET_BLANK
} }
if ctx.Config.NofollowLinks {
htmlFlags |= blackfriday.HTML_NOFOLLOW_LINKS
}
if ctx.Config.SmartDashes { if ctx.Config.SmartDashes {
htmlFlags |= blackfriday.HTML_SMARTYPANTS_DASHES htmlFlags |= blackfriday.HTML_SMARTYPANTS_DASHES
} }

View file

@ -204,6 +204,7 @@ func TestGetHTMLRendererAllFlags(t *testing.T) {
{blackfriday.HTML_SMARTYPANTS_ANGLED_QUOTES}, {blackfriday.HTML_SMARTYPANTS_ANGLED_QUOTES},
{blackfriday.HTML_SMARTYPANTS_FRACTIONS}, {blackfriday.HTML_SMARTYPANTS_FRACTIONS},
{blackfriday.HTML_HREF_TARGET_BLANK}, {blackfriday.HTML_HREF_TARGET_BLANK},
{blackfriday.HTML_NOFOLLOW_LINKS},
{blackfriday.HTML_SMARTYPANTS_DASHES}, {blackfriday.HTML_SMARTYPANTS_DASHES},
{blackfriday.HTML_SMARTYPANTS_LATEX_DASHES}, {blackfriday.HTML_SMARTYPANTS_LATEX_DASHES},
} }
@ -212,6 +213,7 @@ func TestGetHTMLRendererAllFlags(t *testing.T) {
ctx.Config.AngledQuotes = true ctx.Config.AngledQuotes = true
ctx.Config.Fractions = true ctx.Config.Fractions = true
ctx.Config.HrefTargetBlank = true ctx.Config.HrefTargetBlank = true
ctx.Config.NofollowLinks = true
ctx.Config.LatexDashes = true ctx.Config.LatexDashes = true
ctx.Config.PlainIDAnchors = true ctx.Config.PlainIDAnchors = true
ctx.Config.SmartDashes = true ctx.Config.SmartDashes = true