shortcode-templates.md (17519B)
1 ---
2 title: Create Your Own Shortcodes
3 linktitle: Shortcode Templates
4 description: You can extend Hugo's built-in shortcodes by creating your own using the same templating syntax as that for single and list pages.
5 date: 2017-02-01
6 publishdate: 2017-02-01
7 lastmod: 2017-02-01
8 categories: [templates]
9 keywords: [shortcodes,templates]
10 menu:
11 docs:
12 parent: "templates"
13 weight: 100
14 weight: 100
15 sections_weight: 100
16 draft: false
17 aliases: []
18 toc: true
19 ---
20
21 Shortcodes are a means to consolidate templating into small, reusable snippets that you can embed directly inside of your content. In this sense, you can think of shortcodes as the intermediary between [page and list templates][templates] and [basic content files][].
22
23 {{% note %}}
24 Hugo also ships with built-in shortcodes for common use cases. (See [Content Management: Shortcodes](/content-management/shortcodes/).)
25 {{% /note %}}
26
27 ## Create Custom Shortcodes
28
29 Hugo's built-in shortcodes cover many common, but not all, use cases. Luckily, Hugo provides the ability to easily create custom shortcodes to meet your website's needs.
30
31 {{< youtube Eu4zSaKOY4A >}}
32
33 ### File Location
34
35 To create a shortcode, place an HTML template in the `layouts/shortcodes` directory of your [source organization][]. Consider the file name carefully since the shortcode name will mirror that of the file but without the `.html` extension. For example, `layouts/shortcodes/myshortcode.html` will be called with either `{{</* myshortcode /*/>}}` or `{{%/* myshortcode /*/%}}` depending on the type of parameters you choose.
36
37 You can organize your shortcodes in subfolders, e.g. in `layouts/shortcodes/boxes`. These shortcodes would then be accessible with their relative path, e.g:
38
39 ```
40 {{</* boxes/square */>}}
41 ```
42
43 Note the forward slash.
44
45 ### Shortcode Template Lookup Order
46
47 Shortcode templates have a simple [lookup order][]:
48
49 1. `/layouts/shortcodes/<SHORTCODE>.html`
50 2. `/themes/<THEME>/layouts/shortcodes/<SHORTCODE>.html`
51
52 ### Positional vs Named Parameters
53
54 You can create shortcodes using the following types of parameters:
55
56 * Positional parameters
57 * Named parameters
58 * Positional *or* named parameters (i.e, "flexible")
59
60 In shortcodes with positional parameters, the order of the parameters is important. If a shortcode has a single required value (e.g., the `youtube` shortcode below), positional parameters work very well and require less typing from content authors.
61
62 For more complex layouts with multiple or optional parameters, named parameters work best. While less terse, named parameters require less memorization from a content author and can be added in a shortcode declaration in any order.
63
64 Allowing both types of parameters (i.e., a "flexible" shortcode) is useful for complex layouts where you want to set default values that can be easily overridden by users.
65
66 ### Access Parameters
67
68 All shortcode parameters can be accessed via the `.Get` method. Whether you pass a key (i.e., string) or a number to the `.Get` method depends on whether you are accessing a named or positional parameter, respectively.
69
70 To access a parameter by name, use the `.Get` method followed by the named parameter as a quoted string:
71
72 ```
73 {{ .Get "class" }}
74 ```
75
76 To access a parameter by position, use the `.Get` followed by a numeric position, keeping in mind that positional parameters are zero-indexed:
77
78 ```
79 {{ .Get 0 }}
80 ```
81
82 For the second position, you would just use:
83
84 ```
85 {{ .Get 1 }}
86 ```
87
88 `with` is great when the output depends on a parameter being set:
89
90 ```
91 {{ with .Get "class" }} class="{{ . }}"{{ end }}
92 ```
93
94 `.Get` can also be used to check if a parameter has been provided. This is
95 most helpful when the condition depends on either of the values, or both:
96
97 ```
98 {{ if or (.Get "title") (.Get "alt") }} alt="{{ with .Get "alt" }}{{ . }}{{ else }}{{ .Get "title" }}{{ end }}"{{ end }}
99 ```
100
101 #### `.Inner`
102
103 If a closing shortcode is used, the `.Inner` variable will be populated with all of the content between the opening and closing shortcodes. If a closing shortcode is required, you can check the length of `.Inner` as an indicator of its existence.
104
105 A shortcode with content declared via the `.Inner` variable can also be declared without the
106 content and without the closing
107 by using the self-closing syntax:
108
109 ```
110 {{</* innershortcode /*/>}}
111 ```
112
113 #### `.Params`
114
115 The `.Params` variable in shortcodes contains the list parameters passed to shortcode for more complicated use cases. You can also access higher-scoped parameters with the following logic:
116
117 `$.Params`
118 : these are the parameters passed directly into the shortcode declaration (e.g., a YouTube video ID)
119
120 `$.Page.Params`
121 : refers to the page's params; the "page" in this case refers to the content file in which the shortcode is declared (e.g., a `shortcode_color` field in a content's front matter could be accessed via `$.Page.Params.shortcode_color`).
122
123 `$.Page.Site.Params`
124 : refers to global variables as defined in your [site's configuration file][config].
125
126 #### `.IsNamedParams`
127
128 The `.IsNamedParams` variable checks whether the shortcode declaration uses named parameters and returns a boolean value.
129
130 For example, you could create an `image` shortcode that can take either a `src` named parameter or the first positional parameter, depending on the preference of the content's author. Let's assume the `image` shortcode is called as follows:
131
132 ```
133 {{</* image src="images/my-image.jpg" */>}}
134 ```
135
136 You could then include the following as part of your shortcode templating:
137
138 ```
139 {{ if .IsNamedParams }}
140 <img src="{{ .Get "src" }}" alt="">
141 {{ else }}
142 <img src="{{ .Get 0 }}" alt="">
143 {{ end }}
144 ```
145
146 See the [example Vimeo shortcode][vimeoexample] below for `.IsNamedParams` in action.
147
148 {{% warning %}}
149 While you can create shortcode templates that accept both positional and named parameters, you *cannot* declare shortcodes in content with a mix of parameter types. Therefore, a shortcode declared like `{{</* image src="images/my-image.jpg" "This is my alt text" */>}}` will return an error.
150 {{% /warning %}}
151
152 You can also use the variable `.Page` to access all the normal [page variables][pagevars].
153
154 A shortcodes can also be nested. In a nested shortcode, you can access the parent shortcode context with [`.Parent` variable][shortcodesvars]. This can be very useful for inheritance of common shortcode parameters from the root.
155
156 ### Checking for Existence
157
158 You can check if a specific shortcode is used on a page by calling `.HasShortcode` in that page template, providing the name of the shortcode. This is sometimes useful when you want to include specific scripts or styles in the header that are only used by that shortcode.
159
160 ## Custom Shortcode Examples
161
162 The following are examples of the different types of shortcodes you can create via shortcode template files in `/layouts/shortcodes`.
163
164 ### Single-word Example: `year`
165
166 Let's assume you would like to keep mentions of your copyright year current in your content files without having to continually review your markdown. Your goal is to be able to call the shortcode as follows:
167
168 ```
169 {{</* year */>}}
170 ```
171
172 {{< code file="/layouts/shortcodes/year.html" >}}
173 {{ now.Format "2006" }}
174 {{< /code >}}
175
176 ### Single Positional Example: `youtube`
177
178 Embedded videos are a common addition to markdown content that can quickly become unsightly. The following is the code used by [Hugo's built-in YouTube shortcode][youtubeshortcode]:
179
180 ```
181 {{</* youtube 09jf3ow9jfw */>}}
182 ```
183
184 Would load the template at `/layouts/shortcodes/youtube.html`:
185
186 {{< code file="/layouts/shortcodes/youtube.html" >}}
187 <div class="embed video-player">
188 <iframe class="youtube-player" type="text/html" width="640" height="385" src="https://www.youtube.com/embed/{{ index .Params 0 }}" allowfullscreen frameborder="0">
189 </iframe>
190 </div>
191 {{< /code >}}
192
193 {{< code file="youtube-embed.html" copy="false" >}}
194 <div class="embed video-player">
195 <iframe class="youtube-player" type="text/html"
196 width="640" height="385"
197 src="https://www.youtube.com/embed/09jf3ow9jfw"
198 allowfullscreen frameborder="0">
199 </iframe>
200 </div>
201 {{< /code >}}
202
203 ### Single Named Example: `image`
204
205 Let's say you want to create your own `img` shortcode rather than use Hugo's built-in [`figure` shortcode][figure]. Your goal is to be able to call the shortcode as follows in your content files:
206
207 {{< code file="content-image.md" >}}
208 {{</* img src="/media/spf13.jpg" title="Steve Francia" */>}}
209 {{< /code >}}
210
211 You have created the shortcode at `/layouts/shortcodes/img.html`, which loads the following shortcode template:
212
213 {{< code file="/layouts/shortcodes/img.html" >}}
214 <!-- image -->
215 <figure {{ with .Get "class" }}class="{{.}}"{{ end }}>
216 {{ with .Get "link" }}<a href="{{ . }}">{{ end }}
217 <img src="{{ .Get "src" }}" {{ if or (.Get "alt") (.Get "caption") }}alt="{{ with .Get "alt" }}{{ . }}{{ else }}{{ .Get "caption" }}{{ end }}"{{ end }} />
218 {{ if .Get "link" }}</a>{{ end }}
219 {{ if or (or (.Get "title") (.Get "caption")) (.Get "attr") }}
220 <figcaption>{{ if isset .Params "title" }}
221 <h4>{{ .Get "title" }}</h4>{{ end }}
222 {{ if or (.Get "caption") (.Get "attr") }}<p>
223 {{ .Get "caption" }}
224 {{ with .Get "attrlink" }}<a href="{{ . }}"> {{ end }}
225 {{ .Get "attr" }}
226 {{ if .Get "attrlink" }}</a> {{ end }}
227 </p> {{ end }}
228 </figcaption>
229 {{ end }}
230 </figure>
231 <!-- image -->
232 {{< /code >}}
233
234 Would be rendered as:
235
236 {{< code file="img-output.html" copy="false" >}}
237 <figure>
238 <img src="/media/spf13.jpg" />
239 <figcaption>
240 <h4>Steve Francia</h4>
241 </figcaption>
242 </figure>
243 {{< /code >}}
244
245 ### Single Flexible Example: `vimeo`
246
247 ```
248 {{</* vimeo 49718712 */>}}
249 {{</* vimeo id="49718712" class="flex-video" */>}}
250 ```
251
252 Would load the template found at `/layouts/shortcodes/vimeo.html`:
253
254 {{< code file="/layouts/shortcodes/vimeo.html" >}}
255 {{ if .IsNamedParams }}
256 <div class="{{ if .Get "class" }}{{ .Get "class" }}{{ else }}vimeo-container{{ end }}">
257 <iframe src="https://player.vimeo.com/video/{{ .Get "id" }}" allowfullscreen></iframe>
258 </div>
259 {{ else }}
260 <div class="{{ if len .Params | eq 2 }}{{ .Get 1 }}{{ else }}vimeo-container{{ end }}">
261 <iframe src="https://player.vimeo.com/video/{{ .Get 0 }}" allowfullscreen></iframe>
262 </div>
263 {{ end }}
264 {{< /code >}}
265
266 Would be rendered as:
267
268 {{< code file="vimeo-iframes.html" copy="false" >}}
269 <div class="vimeo-container">
270 <iframe src="https://player.vimeo.com/video/49718712" allowfullscreen></iframe>
271 </div>
272 <div class="flex-video">
273 <iframe src="https://player.vimeo.com/video/49718712" allowfullscreen></iframe>
274 </div>
275 {{< /code >}}
276
277 ### Paired Example: `highlight`
278
279 The following is taken from `highlight`, which is a [built-in shortcode][] that ships with Hugo.
280
281 {{< code file="highlight-example.md" >}}
282 {{</* highlight html */>}}
283 <html>
284 <body> This HTML </body>
285 </html>
286 {{</* /highlight */>}}
287 {{< /code >}}
288
289 The template for the `highlight` shortcode uses the following code, which is already included in Hugo:
290
291 ```
292 {{ .Get 0 | highlight .Inner }}
293 ```
294
295 The rendered output of the HTML example code block will be as follows:
296
297 {{< code file="syntax-highlighted.html" copy="false" >}}
298 <div class="highlight" style="background: #272822"><pre style="line-height: 125%"><span style="color: #f92672"><html></span>
299 <span style="color: #f92672"><body></span> This HTML <span style="color: #f92672"></body></span>
300 <span style="color: #f92672"></html></span>
301 </pre></div>
302 {{< /code >}}
303
304 ### Nested Shortcode: Image Gallery
305
306 Hugo's [`.Parent` shortcode variable][parent] returns a boolean value depending on whether the shortcode in question is called within the context of a *parent* shortcode. This provides an inheritance model for common shortcode parameters.
307
308 The following example is contrived but demonstrates the concept. Assume you have a `gallery` shortcode that expects one named `class` parameter:
309
310 {{< code file="layouts/shortcodes/gallery.html" >}}
311 <div class="{{ .Get "class" }}">
312 {{ .Inner }}
313 </div>
314 {{< /code >}}
315
316 You also have an `img` shortcode with a single named `src` parameter that you want to call inside of `gallery` and other shortcodes, so that the parent defines the context of each `img`:
317
318 {{< code file="layouts/shortcodes/img.html" >}}
319 {{- $src := .Get "src" -}}
320 {{- with .Parent -}}
321 <img src="{{$src}}" class="{{ .Get "class" }}-image">
322 {{- else -}}
323 <img src="{{$src}}">
324 {{- end -}}
325 {{< /code >}}
326
327 You can then call your shortcode in your content as follows:
328
329 ```
330 {{</* gallery class="content-gallery" */>}}
331 {{</* img src="/images/one.jpg" */>}}
332 {{</* img src="/images/two.jpg" */>}}
333 {{</* /gallery */>}}
334 {{</* img src="/images/three.jpg" */>}}
335 ```
336
337 This will output the following HTML. Note how the first two `img` shortcodes inherit the `class` value of `content-gallery` set with the call to the parent `gallery`, whereas the third `img` only uses `src`:
338
339 ```
340 <div class="content-gallery">
341 <img src="/images/one.jpg" class="content-gallery-image">
342 <img src="/images/two.jpg" class="content-gallery-image">
343 </div>
344 <img src="/images/three.jpg">
345 ```
346
347
348 ## Error Handling in Shortcodes
349
350 Use the [errorf](/functions/errorf) template func and [.Position](/variables/shortcodes/) variable to get useful error messages in shortcodes:
351
352 ```bash
353 {{ with .Get "name" }}
354 {{ else }}
355 {{ errorf "missing value for param 'name': %s" .Position }}
356 {{ end }}
357 ```
358
359 When the above fails, you will see an `ERROR` log similar to the below:
360
361 ```bash
362 ERROR 2018/11/07 10:05:55 missing value for param name: "/Users/bep/dev/go/gohugoio/hugo/docs/content/en/variables/shortcodes.md:32:1"
363 ```
364
365 ## More Shortcode Examples
366
367 More shortcode examples can be found in the [shortcodes directory for spf13.com][spfscs] and the [shortcodes directory for the Hugo docs][docsshortcodes].
368
369
370 ## Inline Shortcodes
371
372 {{< new-in "0.52" >}}
373
374 Since Hugo 0.52, you can implement your shortcodes inline -- e.g. where you use them in the content file. This can be useful for scripting that you only need in one place.
375
376 This feature is disabled by default, but can be enabled in your site config:
377
378 {{< code-toggle file="config">}}
379 enableInlineShortcodes = true
380 {{< /code-toggle >}}
381
382 It is disabled by default for security reasons. The security model used by Hugo's template handling assumes that template authors are trusted, but that the content files are not, so the templates are injection-safe from malformed input data. But in most situations you have full control over the content, too, and then `enableInlineShortcodes = true` would be considered safe. But it's something to be aware of: It allows ad-hoc [Go Text templates](https://golang.org/pkg/text/template/) to be executed from the content files.
383
384 And once enabled, you can do this in your content files:
385
386 ```go-text-template
387 {{</* time.inline */>}}{{ now }}{{</* /time.inline */>}}
388 ```
389
390 The above will print the current date and time.
391
392 Note that an inline shortcode's inner content is parsed and executed as a Go text template with the same context as a regular shortcode template.
393
394 This means that the current page can be accessed via `.Page.Title` etc. This also means that there are no concept of "nested inline shortcodes".
395
396 The same inline shortcode can be reused later in the same content file, with different params if needed, using the self-closing syntax:
397
398 ```go-text-template
399 {{</* time.inline /*/>}}
400 ```
401
402
403 [basic content files]: /content-management/formats/ "See how Hugo leverages markdown--and other supported formats--to create content for your website."
404 [built-in shortcode]: /content-management/shortcodes/
405 [config]: /getting-started/configuration/ "Learn more about Hugo's built-in configuration variables as well as how to us your site's configuration file to include global key-values that can be used throughout your rendered website."
406 [Content Management: Shortcodes]: /content-management/shortcodes/#using-hugo-s-built-in-shortcodes "Check this section if you are not familiar with the definition of what a shortcode is or if you are unfamiliar with how to use Hugo's built-in shortcodes in your content files."
407 [source organization]: /getting-started/directory-structure/#directory-structure-explained "Learn how Hugo scaffolds new sites and what it expects to find in each of your directories."
408 [docsshortcodes]: https://github.com/gohugoio/hugo/tree/master/docs/layouts/shortcodes "See the shortcode source directory for the documentation site you're currently reading."
409 [figure]: /content-management/shortcodes/#figure
410 [hugosc]: /content-management/shortcodes/#using-hugo-s-built-in-shortcodes
411 [lookup order]: /templates/lookup-order/ "See the order in which Hugo traverses your template files to decide where and how to render your content at build time"
412 [pagevars]: /variables/page/ "See which variables you can leverage in your templating for page vs list templates."
413 [parent]: /variables/shortcodes/
414 [shortcodesvars]: /variables/shortcodes/ "Certain variables are specific to shortcodes, although most .Page variables can be accessed within your shortcode template."
415 [spfscs]: https://github.com/spf13/spf13.com/tree/master/layouts/shortcodes "See more examples of shortcodes by visiting the shortcode directory of the source for spf13.com, the blog of Hugo's creator, Steve Francia."
416 [templates]: /templates/ "The templates section of the Hugo docs."
417 [vimeoexample]: #single-flexible-example-vimeo
418 [youtubeshortcode]: /content-management/shortcodes/#youtube "See how to use Hugo's built-in YouTube shortcode."