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+---
+title: safeURL
+description: Declares the provided string as a safe URL or URL substring.
+godocref: https://golang.org/pkg/html/template/#HTMLEscape
+date: 2017-02-01
+publishdate: 2017-02-01
+lastmod: 2017-02-01
+keywords: [strings,urls]
+categories: [functions]
+menu:
+  docs:
+    parent: "functions"
+signature: ["safeURL INPUT"]
+workson: []
+hugoversion:
+relatedfuncs: []
+deprecated: false
+aliases: []
+---
+
+`safeURL` declares the provided string as a "safe" URL or URL substring (see [RFC 3986][]). A URL like `javascript:checkThatFormNotEditedBeforeLeavingPage()` from a trusted source should go in the page, but by default dynamic `javascript:` URLs are filtered out since they are a frequently exploited injection vector.
+
+Without `safeURL`, only the URI schemes `http:`, `https:` and `mailto:` are considered safe by Go templates. If any other URI schemes (e.g., `irc:` and `javascript:`) are detected, the whole URL will be replaced with `#ZgotmplZ`. This is to "defang" any potential attack in the URL by rendering it useless.
+
+The following examples use a [site `config.toml`][configuration] with the following [menu entry][menus]:
+
+{{< code file="config.toml" copy="false" >}}
+[[menu.main]]
+    name = "IRC: #golang at freenode"
+    url = "irc://irc.freenode.net/#golang"
+{{< /code >}}
+
+The following is an example of a sidebar partial that may be used in conjunction with the preceding front matter example:
+
+{{< code file="layouts/partials/bad-url-sidebar-menu.html" copy="false" >}}
+<!-- This unordered list may be part of a sidebar menu -->
+<ul>
+  {{ range .Site.Menus.main }}
+  <li><a href="{{ .URL }}">{{ .Name }}</a></li>
+  {{ end }}
+</ul>
+{{< /code >}}
+
+This partial would produce the following HTML output:
+
+{{< output file="bad-url-sidebar-menu-output.html" >}}
+<!-- This unordered list may be part of a sidebar menu -->
+<ul>
+    <li><a href="#ZgotmplZ">IRC: #golang at freenode</a></li>
+</ul>
+{{< /output >}}
+
+The odd output can be remedied by adding ` | safeURL` to our `.Title` page variable:
+
+{{< code file="layouts/partials/correct-url-sidebar-menu.html" copy="false" >}}
+<!-- This unordered list may be part of a sidebar menu -->
+<ul>
+    <li><a href="{{ .URL | safeURL }}">{{ .Name }}</a></li>
+</ul>
+{{< /code >}}
+
+With the `.URL` page variable piped through `safeURL`, we get the desired output:
+
+{{< output file="correct-url-sidebar-menu-output.html" >}}
+<ul class="sidebar-menu">
+    <li><a href="irc://irc.freenode.net/#golang">IRC: #golang at freenode</a></li>
+</ul>
+{{< /output >}}
+
+[configuration]: /getting-started/configuration/
+[menus]: /content-management/menus/
+[RFC 3986]: http://tools.ietf.org/html/rfc3986