hugo/content/en/functions/errorf.md
Bjørn Erik Pedersen 4dd90050f1 Squashed 'docs/' changes from 3a923e155..710856e5a
710856e5a Release 0.84.0
362f4ea7b releaser: Add release notes to /docs for release of 0.84.0
6bb8800f7 docs: Regenerate docs helper
00a522e6a docs: Regenerate docshelper
bc171954b Merge commit '92405e5b0adc5d8c3dfde88d6a8b67eb09169190'
ef73ffc3b Misc config loading fixes
0b4117f7f docs: Regenerate docs helper
9b9452b9c Merge commit '32ba623541d74ee0b7ae4efb1b8326dc49af28b8'
9c4413dd9 tpl/fmt: Add erroridf template func
e1875742e tpl/data: Misc header improvements, tests, allow multiple headers of same key
e4560893c Add math.Max and math.Min
7dc282eaf common/maps: Add Scratch.DeleteInMap
b9cd77171 docs: Update querify function description and examples

git-subtree-dir: docs
git-subtree-split: 710856e5a6c683ce26d385960423303cc109c09e
2021-06-18 17:49:54 +02:00

52 lines
1.4 KiB
Markdown

---
title: errorf and warnf
description: Log ERROR or WARNING from the templates.
date: 2017-09-30
publishdate: 2017-09-30
lastmod: 2017-09-30
categories: [functions]
menu:
docs:
parent: "functions"
keywords: [strings, log, error]
signature: ["errorf FORMAT INPUT"]
workson: []
hugoversion:
relatedfuncs: [printf]
deprecated: false
---
`errorf` or `warnf` will evaluate a format string, then output the result to the ERROR or WARNING log (and only once per error message to avoid flooding the log).
Any ERROR will also cause the build to fail (the `hugo` command will `exit -1`).
Both functions return an empty string, so the messages are only printed to the console.
```
{{ errorf "Failed to handle page %q" .Path }}
```
```
{{ warnf "You should update the shortcodes in %q" .Path }}
```
Note that `errorf` and `warnf` support all the formatting verbs of the [fmt](https://golang.org/pkg/fmt/) package.
## Suppress errors
Some times it may make sense to let the user suppress an ERROR and make the build succeed.
You can do this by using the `erroridf` function. This functions takes an error ID as the first arument.
``
{{ erroridf "my-custom-error" "You should consider fixing this."}}
```
This will produce:
```
ERROR 2021/06/07 17:47:38 You should consider fixing this.
If you feel that this should not be logged as an ERROR, you can ignore it by adding this to your site config:
ignoreErrors = ["my-custom-error"]
```