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Fields filter

docs/site/Fields-filter.md

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A fields filter specifies properties (fields) to include or exclude from the results.

Node.js API

<pre> { fields: {<i>propertyName</i>: <true|false>, <i>propertyName</i>: <true|false>, ... } } </pre>

Where:

  • propertyName is the name of the property (field) to include or exclude.
  • <true|false> signifies either true or false Boolean literal. Use true to include the property or false to exclude it from results.

also can be used an array of strings with the properties

<pre> { fields: [<i>propertyName</i>, <i>propertyName</i>, ... ] } </pre>

By default, queries return all model properties in results. However, if you specify at least one fields filter with a value of true or put it in the array, then by default the query will include only those you specifically include with filters.

REST API

<pre> filter[fields]=<i>propertyName</i>&filter[fields]=<i>propertyName</i>... </pre>

Note that to include more than one field in REST, use multiple filters.

Check out the usage of stringified JSON format in a REST query.

Examples

Use case 1: Include required properties.

To return customer information only with name and address, and hide other fields, you can specify all required properties as:

{% include code-caption.html content="Node.js API" %}

ts
await customerRepository.find({fields: ['name', 'address']});

{% include code-caption.html content="REST" %}

Its equivalent stringified JSON format:

/customers?filter={"fields":["name","address"]}

Returns:

ts
[
  {
    name: 'Mario',
    address: '8200 Warden Ave'
  },
  {
    name: 'Luigi',
    address: '999 Avenue Rd'
  },
  ...
]

Use case 2: Exclude properties.

Exclude the password property for returned user:

{% include code-caption.html content="Node.js API" %}

ts
await userRepository.find({fields: {password: false}});

{% include code-caption.html content="REST" %}

Or use stringified JSON format:

/users?filter={"fields":{"password":false}}

Notice that fields clause is to include/exclude the result from the database, e.g if you would like to check password for users, the above example would fail as password is undefined. If you need the property and also want to hide it from the response, set it as a hidden property in the model definition.