resources.GetRemote
Syntax
Returns
New in v0.141.0
The Err method on the returned resource was removed in v0.141.0.
Use the
try statement instead, as shown in the
error handling example below.
{{ $url := "https://example.org/images/a.jpg" }}
{{ with try (resources.GetRemote $url) }}
{{ with .Err }}
{{ errorf "%s" . }}
{{ else with .Value }}
<img src="{{ .RelPermalink }}" width="{{ .Width }}" height="{{ .Height }}" alt="">
{{ else }}
{{ errorf "Unable to get remote resource %q" $url }}
{{ end }}
{{ end }}
Options
The resources.GetRemote function takes an optional map of options.
body
(string) The data you want to transmit to the server.
headers
(map[string][]string) The collection of key-value pairs that provide additional information about the request.
key
(string) The cache key. Hugo derives the default value from the URL and options map. See
caching.
method
(string) The action to perform on the requested resource, typically one of GET, POST, or HEAD.
responseHeaders
New in v0.143.0([]string) The headers to extract from the server’s response, accessible through the resource’s
Data.Headers method. Header name matching is case-insensitive.
Options examples
For brevity, the examples below do not include error handling.
To include a header:
{{ $url := "https://example.org/api" }}
{{ $opts := dict
"headers" (dict "Authorization" "Bearer abcd")
}}
{{ $resource := resources.GetRemote $url $opts }}
To specify more than one value 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 }}
To post data:
{{ $url := "https://example.org/api" }}
{{ $opts := dict
"method" "post"
"body" `{"complete": true}`
"headers" (dict "Content-Type" "application/json")
}}
{{ $resource := resources.GetRemote $url $opts }}
To override the default cache key:
{{ $url := "https://example.org/images/a.jpg" }}
{{ $opts := dict
"key" (print $url (now.Format "2006-01-02"))
}}
{{ $resource := resources.GetRemote $url $opts }}
To extract specific headers from the server’s response:
{{ $url := "https://example.org/images/a.jpg" }}
{{ $opts := dict
"method" "HEAD"
"responseHeaders" (slice "X-Frame-Options" "Server")
}}
{{ $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 try (resources.GetRemote $url) }}
{{ with .Err }}
{{ errorf "%s" . }}
{{ else with .Value }}
{{ $data = . | transform.Unmarshal }}
{{ else }}
{{ errorf "Unable to get remote resource %q" $url }}
{{ end }}
{{ 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
Use the
try statement to capture HTTP request errors. If you do not handle the error yourself, Hugo will fail the build.
Hugo does not classify an HTTP response with status code 404 as an error. In this case resources.GetRemote returns nil.
{{ $url := "https://broken-example.org/images/a.jpg" }}
{{ with try (resources.GetRemote $url) }}
{{ with .Err }}
{{ errorf "%s" . }}
{{ else with .Value }}
<img src="{{ .RelPermalink }}" width="{{ .Width }}" height="{{ .Height }}" alt="">
{{ else }}
{{ errorf "Unable to get remote resource %q" $url }}
{{ end }}
{{ end }}
To log an error as a warning instead of an error:
{{ $url := "https://broken-example.org/images/a.jpg" }}
{{ with try (resources.GetRemote $url) }}
{{ with .Err }}
{{ warnf "%s" . }}
{{ else with .Value }}
<img src="{{ .RelPermalink }}" width="{{ .Width }}" height="{{ .Height }}" alt="">
{{ else }}
{{ warnf "Unable to get remote resource %q" $url }}
{{ end }}
{{ end }}
HTTP response
The
Data method on a resource returned by the resources.GetRemote function returns information from the HTTP response.
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") }}
{{ $opts := dict "key" $cacheKey }}
{{ $resource := resources.GetRemote $url $opts }}
Security
To protect against malicious intent, the resources.GetRemote function inspects the server response including:
- The Content-Type in the response header
- The file extension, if any
- The content itself
If Hugo is unable to resolve the media type to an entry in its allowlist, the function throws an error:
ERROR error calling resources.GetRemote: failed to resolve media type...
For example, you will see the error above if you attempt to download an executable.
Although the allowlist contains entries for common media types, you may encounter situations where Hugo is unable to resolve the media type of a file that you know to be safe. In these situations, edit your site configuration to add the media type to the allowlist. For example:
security:
http:
mediaTypes:
- ^image/avif$
- ^application/vnd\.api\+json$
[security]
[security.http]
mediaTypes = ['^image/avif$', '^application/vnd\.api\+json$']
{
"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