mirror of https://github.com/grafana/grafana.git
75 lines
2.3 KiB
Markdown
75 lines
2.3 KiB
Markdown
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---
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title: Work with error handling
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aliases:
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- ../../plugins/error-handling/
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description: How to handle errors in plugins.
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keywords:
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- grafana
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- plugins
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- plugin
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- errors
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- error handling
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---
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# Work with error handling
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This guide explains how to handle errors in plugins and provides suggestions for common scenarios.
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## Provide usable defaults
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Allow the user to learn your plugin in small steps. Provide a useful default configuration so that:
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- The user can get started right away.
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- You can avoid unnecessary error messages.
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For example, by selecting the first field of an expected type, the panel can display a visualization without any user configuration. If a user explicitly selects a field, then use that one. Otherwise, default to the first field of type `string`:
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```ts
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const numberField = frame.fields.find((field) =>
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options.numberFieldName ? field.name === options.numberFieldName : field.type === FieldType.number
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);
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```
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## Display error messages
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To display an error message to the user, `throw` an `Error` with the message you want to display:
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```ts
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throw new Error('An error occurred');
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```
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Grafana displays the error message in the top-left corner of the panel.
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{{< figure src="/static/img/docs/panel_error.png" class="docs-image--no-shadow" max-width="850px" >}}
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We recommend that you avoid displaying overly technical error messages to the user. If you want to let technical users report an error, consider logging it to the console instead.
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```ts
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try {
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failingFunction();
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} catch (err) {
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console.error(err);
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throw new Error('Something went wrong');
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}
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```
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> **Note:** Grafana displays the exception message in the UI as written, so use grammatically correct sentences. For more information, refer to the [Documentation style guide](/docs/writers-toolkit/).
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## Common error scenarios
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Here are some examples of situations where you might want to display an error to the user.
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### Invalid query response
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Users have full freedom when they create data source queries for panels. If your panel plugin requires a specific format for the query response, then use the panel canvas to guide the user.
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```ts
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if (!numberField) {
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throw new Error('Query result is missing a number field');
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}
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if (frame.length === 0) {
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throw new Error('Query returned an empty result');
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}
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```
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