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hugo/docs/content/en/content-management/content-adapters.md

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---
title: Content adapters
description: Create content adapters to dynamically add content when building your site.
categories: []
keywords: []
---
{{< new-in 0.126.0 />}}
## Overview
A content adapter is a template that dynamically creates pages when building a site. For example, use a content adapter to create pages from a remote data source such as JSON, TOML, YAML, or XML.
Unlike templates that reside in the `layouts` directory, content adapters reside in the `content` directory, no more than one per directory per language. When a content adapter creates a page, the page's [logical path](g) will be relative to the content adapter.
```text
content/
├── articles/
│ ├── _index.md
│ ├── article-1.md
│ └── article-2.md
├── books/
│ ├── _content.gotmpl <-- content adapter
│ └── _index.md
└── films/
├── _content.gotmpl <-- content adapter
└── _index.md
```
Each content adapter is named _content.gotmpl and uses the same [syntax] as templates in the `layouts` directory. You can use any of the [template functions] within a content adapter, as well as the methods described below.
## Methods
Use these methods within a content adapter.
### AddPage
Adds a page to the site.
```go-html-template {file="content/books/_content.gotmpl"}
{{ $content := dict
"mediaType" "text/markdown"
"value" "The _Hunchback of Notre Dame_ was written by Victor Hugo."
}}
{{ $page := dict
"content" $content
"kind" "page"
"path" "the-hunchback-of-notre-dame"
"title" "The Hunchback of Notre Dame"
}}
{{ .AddPage $page }}
```
### AddResource
Adds a page resource to the site.
```go-html-template {file="content/books/_content.gotmpl"}
{{ with resources.Get "images/a.jpg" }}
{{ $content := dict
"mediaType" .MediaType.Type
"value" .
}}
{{ $resource := dict
"content" $content
"path" "the-hunchback-of-notre-dame/cover.jpg"
}}
{{ $.AddResource $resource }}
{{ end }}
```
Then retrieve the new page resource with something like:
```go-html-template {file="layouts/_default/single.html"}
{{ with .Resources.Get "cover.jpg" }}
<img src="{{ .RelPermalink }}" width="{{ .Width }}" height="{{ .Height }}" alt="">
{{ end }}
```
### Site
Returns the `Site` to which the pages will be added.
```go-html-template {file="content/books/_content.gotmpl"}
{{ .Site.Title }}
```
> [!note]
> Note that the `Site` returned isn't fully built when invoked from the content adapters; if you try to call methods that depends on pages, e.g. `.Site.Pages`, you will get an error saying "this method cannot be called before the site is fully initialized".
### Store
Returns a persistent “scratch pad” to store and manipulate data. The main use case for this is to transfer values between executions when [EnableAllLanguages](#enablealllanguages) is set. See [examples](/methods/page/store/).
```go-html-template {file="content/books/_content.gotmpl"}
{{ .Store.Set "key" "value" }}
{{ .Store.Get "key" }}
```
### EnableAllLanguages
By default, Hugo executes the content adapter for the language defined by the _content.gotmpl file. Use this method to activate the content adapter for all languages.
```go-html-template {file="content/books/_content.gotmpl"}
{{ .EnableAllLanguages }}
{{ $content := dict
"mediaType" "text/markdown"
"value" "The _Hunchback of Notre Dame_ was written by Victor Hugo."
}}
{{ $page := dict
"content" $content
"kind" "page"
"path" "the-hunchback-of-notre-dame"
"title" "The Hunchback of Notre Dame"
}}
{{ .AddPage $page }}
```
## Page map
Set any [front matter field] in the map passed to the [`AddPage`](#addpage) method, excluding `markup`. Instead of setting the `markup` field, specify the `content.mediaType` as described below.
This table describes the fields most commonly passed to the `AddPage` method.
Key|Description|Required
:--|:--|:-:
`content.mediaType`|The content [media type]. Default is `text/markdown`. See [content formats] for examples.|&nbsp;
`content.value`|The content value as a string.|&nbsp;
`dates.date`|The page creation date as a `time.Time` value.|&nbsp;
`dates.expiryDate`|The page expiry date as a `time.Time` value.|&nbsp;
`dates.lastmod`|The page last modification date as a `time.Time` value.|&nbsp;
`dates.publishDate`|The page publication date as a `time.Time` value.|&nbsp;
`params`|A map of page parameters.|&nbsp;
`path`|The page's [logical path](g) relative to the content adapter. Do not include a leading slash or file extension.|:heavy_check_mark:
`title`|The page title.|&nbsp;
> [!note]
> While `path` is the only required field, we recommend setting `title` as well.
>
> When setting the `path`, Hugo transforms the given string to a logical path. For example, setting `path` to `A B C` produces a logical path of `/section/a-b-c`.
## Resource map
Construct the map passed to the [`AddResource`](#addresource) method using the fields below.
Key|Description|Required
:--|:--|:-:
`content.mediaType`|The content [media type].|:heavy_check_mark:
`content.value`|The content value as a string or resource.|:heavy_check_mark:
`name`|The resource name.|&nbsp;
`params`|A map of resource parameters.|&nbsp;
`path`|The resources's [logical path](g) relative to the content adapter. Do not include a leading slash.|:heavy_check_mark:
`title`|The resource title.|&nbsp;
> [!note]
> If the `content.value` is a string Hugo creates a new resource. If the `content.value` is a resource, Hugo obtains the value from the existing resource.
>
> When setting the `path`, Hugo transforms the given string to a logical path. For example, setting `path` to `A B C/cover.jpg` produces a logical path of `/section/a-b-c/cover.jpg`.
## Example
Create pages from remote data, where each page represents a book review.
### Step 1
Create the content structure.
```text
content/
└── books/
├── _content.gotmpl <-- content adapter
└── _index.md
```
### Step 2
Inspect the remote data to determine how to map key-value pairs to front matter fields.\
<https://gohugo.io/shared/examples/data/books.json>
### Step 3
Create the content adapter.
```go-html-template {file="content/books/_content.gotmpl" copy=true}
{{/* Get remote data. */}}
{{ $data := dict }}
{{ $url := "https://gohugo.io/shared/examples/data/books.json" }}
{{ with try (resources.GetRemote $url) }}
{{ with .Err }}
{{ errorf "Unable to get remote resource %s: %s" $url . }}
{{ else with .Value }}
{{ $data = . | transform.Unmarshal }}
{{ else }}
{{ errorf "Unable to get remote resource %s" $url }}
{{ end }}
{{ end }}
{{/* Add pages and page resources. */}}
{{ range $data }}
{{/* Add page. */}}
{{ $content := dict "mediaType" "text/markdown" "value" .summary }}
{{ $dates := dict "date" (time.AsTime .date) }}
{{ $params := dict "author" .author "isbn" .isbn "rating" .rating "tags" .tags }}
{{ $page := dict
"content" $content
"dates" $dates
"kind" "page"
"params" $params
"path" .title
"title" .title
}}
{{ $.AddPage $page }}
{{/* Add page resource. */}}
{{ $item := . }}
{{ with $url := $item.cover }}
{{ with try (resources.GetRemote $url) }}
{{ with .Err }}
{{ errorf "Unable to get remote resource %s: %s" $url . }}
{{ else with .Value }}
{{ $content := dict "mediaType" .MediaType.Type "value" .Content }}
{{ $params := dict "alt" $item.title }}
{{ $resource := dict
"content" $content
"params" $params
"path" (printf "%s/cover.%s" $item.title .MediaType.SubType)
}}
{{ $.AddResource $resource }}
{{ else }}
{{ errorf "Unable to get remote resource %s" $url }}
{{ end }}
{{ end }}
{{ end }}
{{ end }}
```
### Step 4
Create a single template to render each book review.
```go-html-template {file="layouts/books/single.html" copy=true}
{{ define "main" }}
<h1>{{ .Title }}</h1>
{{ with .Resources.GetMatch "cover.*" }}
<img src="{{ .RelPermalink }}" width="{{ .Width }}" height="{{ .Height }}" alt="{{ .Params.alt }}">
{{ end }}
<p>Author: {{ .Params.author }}</p>
<p>
ISBN: {{ .Params.isbn }}<br>
Rating: {{ .Params.rating }}<br>
Review date: {{ .Date | time.Format ":date_long" }}
</p>
{{ with .GetTerms "tags" }}
<p>Tags:</p>
<ul>
{{ range . }}
<li><a href="{{ .RelPermalink }}">{{ .LinkTitle }}</a></li>
{{ end }}
</ul>
{{ end }}
{{ .Content }}
{{ end }}
```
## Multilingual sites
With multilingual sites you can:
1. Create one content adapter for all languages using the [`EnableAllLanguages`](#enablealllanguages) method as described above.
1. Create content adapters unique to each language. See the examples below.
### Translations by file name
With this site configuration:
{{< code-toggle file=hugo >}}
[languages.en]
weight = 1
[languages.de]
weight = 2
{{< /code-toggle >}}
Include a language designator in the content adapter's file name.
```text
content/
└── books/
├── _content.de.gotmpl
├── _content.en.gotmpl
├── _index.de.md
└── _index.en.md
```
### Translations by content directory
With this site configuration:
{{< code-toggle file=hugo >}}
[languages.en]
contentDir = 'content/en'
weight = 1
[languages.de]
contentDir = 'content/de'
weight = 2
{{< /code-toggle >}}
Create a single content adapter in each directory:
```text
content/
├── de/
│ └── books/
│ ├── _content.gotmpl
│ └── _index.md
└── en/
└── books/
├── _content.gotmpl
└── _index.md
```
## Page collisions
Two or more pages collide when they have the same publication path. Due to concurrency, the content of the published page is indeterminate. Consider this example:
```text
content/
└── books/
├── _content.gotmpl <-- content adapter
├── _index.md
└── the-hunchback-of-notre-dame.md
```
If the content adapter also creates books/the-hunchback-of-notre-dame, the content of the published page is indeterminate. You can not define the processing order.
To detect page collisions, use the `--printPathWarnings` flag when building your site.
[content formats]: /content-management/formats/#classification
[front matter field]: /content-management/front-matter/#fields
[media type]: https://en.wikipedia.org/wiki/Media_type
[syntax]: /templates/introduction/
[template functions]: /functions/