Skip to main content

resources.GetRemote

{{ $url := "https://example.org/images/a.jpg" }}
{{ with resources.GetRemote $url }}
  {{ with .Err }}
    {{ errorf "%s" . }}
  {{ else }}
    <img src="{{ .RelPermalink }}" width="{{ .Width }}" height="{{ .Height }}" alt="">
  {{ end }}
{{ else }}
  {{ errorf "Unable to get remote resource %q" $url }}
{{ end }}

Options​

The resources.GetRemote function takes an optional map of options.

{{ $url := "https://example.org/api" }}
{{ $opts := dict
  "headers" (dict "Authorization" "Bearer abcd")
}}
{{ $resource := resources.GetRemote $url $opts }}

If you need multiple values for the same header key, use a slice:

{{ $url := "https://example.org/api" }}
{{ $opts := dict
  "headers" (dict "X-List" (slice "a" "b" "c"))
}}
{{ $resource := resources.GetRemote $url $opts }}

You can also change the request method and set the request body:

{{ $url := "https://example.org/api" }}
{{ $opts := dict
  "method" "post"
  "body" `{"complete": true}` 
  "headers" (dict  "Content-Type" "application/json")
}}
{{ $resource := resources.GetRemote $url $opts }}

Remote data​

When retrieving remote data, use the transform.Unmarshal function to unmarshal the response.

{{ $data := dict }}
{{ $url := "https://example.org/books.json" }}
{{ with resources.GetRemote $url }}
  {{ with .Err }}
    {{ errorf "%s" . }}
  {{ else }}
    {{ $data = . | transform.Unmarshal }}
  {{ end }}
{{ else }}
  {{ errorf "Unable to get remote resource %q" $url }}
{{ end }}

When retrieving remote data, a misconfigured server may send a response header with an incorrect Content-Type. For example, the server may set the Content-Type header to application/octet-stream instead of application/json.

In these cases, pass the resource Content through the transform.Unmarshal function instead of passing the resource itself. For example, in the above, do this instead:

{{ $data = .Content | transform.Unmarshal }}

Error handling​

The Err method on a resource returned by the resources.GetRemote function returns an error message if the HTTP request fails, else nil. If you do not handle the error yourself, Hugo will fail the build.

{{ $url := "https://broken-example.org/images/a.jpg" }}
{{ with resources.GetRemote $url }}
  {{ with .Err }}
    {{ errorf "%s" . }}
  {{ else }}
    <img src="{{ .RelPermalink }}" width="{{ .Width }}" height="{{ .Height }}" alt="">
  {{ end }}
{{ else }}
  {{ errorf "Unable to get remote resource %q" $url }}
{{ end }}

To log an error as a warning instead of an error:

{{ $url := "https://broken-example.org/images/a.jpg" }}
{{ with resources.GetRemote $url }}
  {{ with .Err }}
    {{ warnf "%s" . }}
  {{ else }}
    <img src="{{ .RelPermalink }}" width="{{ .Width }}" height="{{ .Height }}" alt="">
  {{ end }}
{{ else }}
  {{ errorf "Unable to get remote resource %q" $url }}
{{ end }}

HTTP response​

The Data method on a resource returned by the resources.GetRemote function returns information from the HTTP response.

{{ $url := "https://example.org/images/a.jpg" }}
{{ with resources.GetRemote $url }}
  {{ with .Err }}
    {{ errorf "%s" . }}
  {{ else }}
    {{ with .Data }}
      {{ .ContentLength }} → 42764
      {{ .ContentType }} → image/jpeg
      {{ .Status }} → 200 OK
      {{ .StatusCode }} → 200
      {{ .TransferEncoding }} → []
    {{ end }}
  {{ end }}
{{ else }}
  {{ errorf "Unable to get remote resource %q" $url }}
{{ end }}

ContentLength : (int) The content length in bytes.

ContentType : (string) The content type.

Status : (string) The HTTP status text.

StatusCode : (int) The HTTP status code.

TransferEncoding : (string) The transfer encoding.

Caching​

Resources returned from resources.GetRemote are cached to disk. See configure file caches for details.

By default, Hugo derives the cache key from the arguments passed to the function, the URL and the options map, if any.

Override the cache key by setting a key in the options map. Use this approach to have more control over how often Hugo fetches a remote resource.

{{ $url := "https://example.org/images/a.jpg" }}
{{ $cacheKey := print $url (now.Format "2006-01-02") }}
{{ $resource := resources.GetRemote $url (dict "key" $cacheKey) }}

Security​

To protect against malicious intent, the resources.GetRemote function inspects the server response including:

  • The Content-Type in the response header
  • The file extension, if any
  • The content itself

If Hugo is unable to resolve the media type to an entry in its allowlist, the function throws an error:

ERROR error calling resources.GetRemote: failed to resolve media type...

For example, you will see the error above if you attempt to download an executable.

Although the allowlist contains entries for common media types, you may encounter situations where Hugo is unable to resolve the media type of a file that you know to be safe. In these situations, edit your site configuration to add the media type to the allowlist. For example:

[security.http]
mediaTypes = ['^image/avif$','^application/vnd\.api\+json$']

Note that the entry above is:

  • An addition to the allowlist; it does not replace the allowlist
  • An array of regular expressions