ra-relationships

A set of alternative inputs and fields to edit relationships, including many-to-many relationships using a join table.

Test it live in the Enterprise Edition Storybook.

Installation

npm install --save @react-admin/ra-relationships
# or
yarn add @react-admin/ra-relationships

Tip: ra-relationships is part of the React-Admin Enterprise Edition, and hosted in a private npm registry. You need to subscribe to one of the Enterprise Edition plans to access this package.

The package contains new translation messages (in English and French). You should add them to your i18nProvider:

import { Admin } from 'react-admin';
import polyglotI18nProvider from 'ra-i18n-polyglot';
import englishMessages from 'ra-language-english';
import frenchMessages from 'ra-language-french';

import {
    raRelationshipsLanguageEnglish,
    raRelationshipsLanguageFrench,
} from '@react-admin/ra-relationships';

const messages = {
    en: { ...englishMessages, ...raRelationshipsLanguageEnglish },
    fr: { ...frenchMessages, ...raRelationshipsLanguageFrench },
};

const i18nProvider = polyglotI18nProvider(locale => messages[locale], 'en');

const App = () => <Admin i18nProvider={is18nProvider}>{/* ... */}</Admin>;

import { Admin } from 'react-admin';
import polyglotI18nProvider from 'ra-i18n-polyglot';
import englishMessages from 'ra-language-english';
import frenchMessages from 'ra-language-french';

import {
    raRelationshipsLanguageEnglish,
    raRelationshipsLanguageFrench,
} from '@react-admin/ra-relationships';

const messages = {
    en: { ...englishMessages, ...raRelationshipsLanguageEnglish },
    fr: { ...frenchMessages, ...raRelationshipsLanguageFrench },
};

const i18nProvider = polyglotI18nProvider(locale => messages[locale], 'en');

const App = () => <Admin i18nProvider={is18nProvider}>{/* ... */}</Admin>;

Many-To-Many Relationships

Developers usually store many-to-many relationships in databases using an associative table (also known as join table, junction table or cross-reference table). For instance, if a Book can have many Authors, and an Author can write several Books, the normalized way to store this relationship in a relational database uses an intermediate table book_authors, as follows:

┌──────────────────┐       ┌──────────────┐      ┌───────────────┐
│ books            │       │ book_authors │      │ authors       │
│------------------│       │--------------│      │---------------│
│ id               │───┐   │ id           │   ┌──│ id            │
│ title            │   └──╼│ book_id      │   │  │ first_name    │
│ body             │       │ author_id    │╾──┘  │ last_name     │
│ publication_date │       │ is_public    │      │ date_of_birth │
└──────────────────┘       └──────────────┘      └───────────────┘

In the book_authors table, book_id and author_id are both foreign keys to books and authors.

A REST API closely following this data model exposes the three resources /books, /authors, and /book_authors. ra-relationships components rely on the associative table without ever showing it to the end-user. From the end user's point of view, the associative table is an implementation detail.

Out of scope

If the associative table uses a composite primary key, then ra-relationships does not work, as react-admin requires that all entities expose an identifier called id. For example, if user permissions are seen as a many-to-many relationship, they can be modeled in a relational database as follows:

users         user_permissions    permissions
----------    ----------------    -----------------
login         user_login          key
password      permission_key      description
first_name
last_name

Here, the associative table uses a composite primary key made of the tuple (user_login, permission_key). To allow react-admin to use this associative table, the related API route (/user_permissions) must include a unique id field for each record (which can simply be the concatenation of the two foreign keys).

Also, if your REST API can present that relationship through a list of related record ids (e.g. author_ids in books and book_ids in authors), you don't need ra-relationships. Just use <ReferenceArrayField> and <ReferenceArrayInput>, which are standard components in react-admin.

<ReferenceOneInput>

Use <ReferenceOneInput> in an <Edit> or <Create> view to edit a record linked to the current record via a one-to-one relationship, e.g. to edit the details of a book in the book edition view.

<ReferenceOneInput> renders the inputs provided as its children, and fetches the related record to populate them. When users change the related record fields, the <ReferenceOneInput> component stores these changes locally. Then, when users actually submit the form, <ReferenceOneInput> will update both the base record and the related record.

Usage

Here is an example one-to-one relationship: a book has at most one book_details row associated to it.

┌─────────────┐       ┌──────────────┐
│ book        │       │ book_details │
│-------------│       │--------------│
│ id          │───┐   │ id           │
│ title       │   └──╼│ book_id      │
└─────────────┘       │ year         │
                      │ author       │
                      │ country      │
                      │ genre        │
                      │ pages        │
                      └──────────────┘

You probably want to let users edit the book details directly from the book Edition view (instead of having to go to the book details Edition view). <ReferenceOneInput> allows to do that.

import {
    Edit,
    SimpleForm,
    TextInput,
    NumberInput,
} from 'react-admin';
import { ReferenceOneInput } from '@react-admin/ra-relationships';

const BookEdit = () => (
    <Edit mutationMode="optimistic">
        <SimpleForm>
            <TextInput source="title" />
            <ReferenceOneInput reference="book_details" target="book_id">
                <NumberInput source="year" />
                <TextInput source="author" />
                <TextInput source="country" />
                <TextInput source="genre" />
                <NumberInput source="pages" />
            </ReferenceOneInput>
        </SimpleForm>
    </Edit>
);

<ReferenceOneInput> requires a reference and a target prop to know which entity to fetch, and one or more inputs as its children to edit the related record.

<ReferenceOneInput> persists the changes in the referenced record (book details in the above example) after persisting the changes in the main resource (book in the above example). This means that you can also use <ReferenceOneInput> in <Create> views.

Tip: <ReferenceOneInput> cannot be used with undoable mutations. You have to set mutationMode="optimistic" or mutationMode="pessimistic" in the parent <Edit> or <Create>, as in the example above.

Props

Additional props are passed to the MUI <Stack> component.

children

<ReferenceOneInput> expects input components as its children (like <TextInput>, <NumberInput>, etc.), which will allow to edit the related record. The inputs will be rendered inside an MUI <Stack>.

<ReferenceOneInput reference="book_details" target="book_id">
    <NumberInput source="year" />
    <TextInput source="author" />
    <TextInput source="country" />
    <TextInput source="genre" />
    <NumberInput source="pages" />
</ReferenceOneInput>

Important note: <ReferenceOneInput> works by cloning its children and overriding their source prop, to add a temporary field name prefix. This means that, if you need to nest your inputs inside another component, you need to propagate the source prop to them.

defaultValue

<ReferenceOneInput> allows to specify a default value for the related record. This is useful when the current record does not yet have a related record, and you want to pre-fill the related record with some default values.

<ReferenceOneInput
    reference="book_details"
    target="book_id"
    defaultValue={{ author: 'Gustave Flaubert', year: 1857 }}
>
    <NumberInput source="year" />
    <TextInput source="author" />
    <TextInput source="country" />
    <TextInput source="genre" />
    <NumberInput source="pages" />
</ReferenceOneInput>

filter

<ReferenceOneInput> allows to specify filters to use when fetching the related record. This can be useful when you need additional filters to select the related record.

<ReferenceOneInput
    reference="book_details"
    target="book_id"
    filter={{ reviewed: true }}
>
    ...
</ReferenceOneInput>

label

By default, <ReferenceOneInput> humanizes the reference name to build a label. You can customize the label by passing the label prop.

<ReferenceOneInput
    reference="book_details"
    target="book_id"
    label="Detailed information about the book"
>
    ...
</ReferenceOneInput>

React-admin uses the i18n system to translate the label, so you can use translation keys to have one label for each language supported by the interface:

<ReferenceOneInput
    reference="book_details"
    target="book_id"
    label="resource.books.fields.details"
>
    ...
</ReferenceOneInput>

reference

The name of the resource to fetch for the related records.

For instance, if you want to display the book_details of a given book, the reference name should be book_details:

<ReferenceOneInput reference="book_details" target="book_id">
    ...
</ReferenceOneInput>

sort

<ReferenceOneInput> allows to specify the sort options used when fetching the related record. This can be useful when the relation table does not have an id column.

<ReferenceOneInput
    reference="book_details"
    target="book_id"
    sort={{ field: '_id', order: 'DESC' }}
>
    ...
</ReferenceOneInput>

source

By default, <ReferenceManyInput> fetches the reference for which the target field equals the current record id. You can customize the field that carries the identity of the current record by setting the source prop.

<ReferenceOneInput reference="book_details" target="book_id" source="_id">
    ...
</ReferenceOneInput>

sx

You can override the style of the root component (a MUI <FormControl>) and its child components by setting the sx prop.

<ReferenceOneInput
  reference="book_details"
  target="book_id"
  sx={{ border: '1px solid red' }}
>
   ...
</ReferenceOneInput>

target

Name of the field carrying the relationship on the referenced resource. For instance, if each book is linked to a record in book_details, and each book_details exposes a book_id field linking to the book, the target would be book_id.

<ReferenceOneInput reference="book_details" target="book_id">
    ...
</ReferenceOneInput>

Limitations

• <ReferenceOneInput> cannot be used inside an <ArrayInput> or a <ReferenceManyInput>.
• <ReferenceOneInput> cannot have a <ReferenceManyInput> as one of its children.

<ReferenceManyInput>

Use <ReferenceManyInput> in an <Edit> or <Create> view to edit one-to-many relationships, e.g. to edit the variants of a product in the product edition view.

<ReferenceManyInput> fetches the related records, and renders them in a sub-form. When users add, remove of update related records, the <ReferenceManyInput> component stores these changes locally. When the users actually submit the form, <ReferenceManyInput> computes a diff with the existing relationship, and sends the related changes (additions, deletions, and updates) to the server.

Usage

An example one-to-many relationship can be found in ecommerce systems: a product has many variants.

┌───────────────┐       ┌──────────────┐
│ products      │       │ variants     │
│---------------│       │--------------│
│ id            │───┐   │ id           │
│ name          │   └──╼│ product_id   │
│ price         │       │ sku          │
│ category_id   │       │ size         │
└───────────────┘       │ color        │
                        │ stock        │
                        └──────────────┘

You probably want to let users edit variants directly from the product Edition view (instead of having to go to the variant Edition view). <ReferenceManyInput> allows to do that.

import {
    Edit,
    SimpleForm,
    TextInput,
    NumberInput,
    ReferenceInput,
    SelectInput,
} from 'react-admin';
import { ReferenceManyInput } from '@react-admin/ra-relationships';

const ProductEdit = () => (
    <Edit mutationMode="optimistic">
        <SimpleForm>
            <TextInput source="name" />
            <NumberInput source="price" />
            <ReferenceInput source="category_id" reference="categories" />
            <ReferenceManyInput reference="variants" target="product_id">
                <SimpleFormIterator inline>
                    <TextInput source="sku" />
                    <SelectInput source="size" choices={sizes} />
                    <SelectInput source="color" choices={colors} />
                    <NumberInput source="stock" defaultValue={0} />
                </SimpleFormIterator>
            </ReferenceManyInput>
        </SimpleForm>
    </Edit>
);

<ReferenceManyInput> requires a reference and a target prop to know which entity to fetch, and a child component (usually a <SimpleFormIterator>) to edit the relationship.

<ReferenceManyInput> persists the changes in the reference records (variants in the above example) after persisting the changes in the main resource (product in the above example). This means that you can also use <ReferenceManyInput> in <Create> views.

Tip: <ReferenceManyInput> cannot be used with undoable mutations. You have to set mutationMode="optimistic" or mutationMode="pessimistic" in the parent <Edit> or <Create>, as in the example above.

Props

children

<ReferenceManyInput> creates an <ArrayInputContext>, so it accepts the same type of children as <ArrayInput>: a Form iterator. React-admin bundles one such iterator: <SimpleFormIterator>. It renders one row for each related record, giving the user the ability to add, remove, or edit related records.

<ReferenceManyInput reference="variants" target="product_id">
    <SimpleFormIterator>
        <TextInput source="sku" />
        <SelectInput source="size" choices={sizes} />
        <SelectInput source="color" choices={colors} />
        <NumberInput source="stock" defaultValue={0} />
    </SimpleFormIterator>
</ReferenceManyInput>

Check out the <SimpleFormIterator> documentation for more details.

defaultValue

When the current record has no related records, <ReferenceManyInput> renders an empty list with an "Add" button to add related records.

You can use the defaultValue prop to populate the list of related records in that case. It must be an array of objects.

<ReferenceManyInput
    reference="variants"
    target="product_id"
    defaultValue={[
        { sku: 'SKU_1', size: 'S', color: 'black', stock: 0 },
        { sku: 'SKU_2', size: 'M', color: 'black', stock: 0 },
        { sku: 'SKU_3', size: 'L', color: 'black', stock: 0 },
        { sku: 'SKU_4', size: 'XL', color: 'black', stock: 0 },
    ]}
>
    <SimpleFormIterator>
        <TextInput source="sku" />
        <SelectInput source="size" choices={sizes} />
        <SelectInput source="color" choices={colors} />
        <NumberInput source="stock" defaultValue={0} />
    </SimpleFormIterator>
</ReferenceManyInput>

filter

You can filter the query used to populate the current values. Use the filter prop for that.

<ReferenceManyInput
    reference="variants"
    target="product_id"
    filter={{ is_published: true }}
>
    ...
</ReferenceManyInput>

helperText

If you need to display a text below the input (usually to explain the expected data to the user), use the helperText prop.

<ReferenceManyInput
    reference="variants"
    target="product_id"
    helperText="Enter at least 5 variants for each product"
>
    ...
</ReferenceManyInput>

label

By default, <ReferenceManyInput> humanizes the reference name to build a label. You can customize the label by passing the label prop.

<ReferenceManyInput
    reference="variants"
    target="product_id"
    label="Product variants"
>
    ...
</ReferenceManyInput>

React-admin uses the i18n system to translate the label, so you can use translation keys to have one label for each language supported by the interface:

<ReferenceManyInput
    reference="variants"
    target="product_id"
    label="resource.products.fields.variants"
>
    ...
</ReferenceManyInput>

perPage

By default, react-admin restricts the possible values to 25 and displays no pagination control. You can change the limit by setting the perPage prop:

<ReferenceManyInput reference="variants" target="product_id" perPage={10}>
    ...
</ReferenceManyInput>

reference

The name of the resource to fetch for the related records.

For instance, if you want to display the variants of a given product, the reference name should be variants:

<ReferenceManyInput reference="books" target="author_id">
    ...
</ReferenceManyInput>

sort

By default, related records appear ordered by id desc. You can change this order by setting the sort prop (an object with field and order properties).

<ReferenceManyInput
  reference="variants"
  target="product_id"
  sort={{ field: 'sku', order: 'ASC' }}
>
   ...
</ReferenceManyField>

source

By default, <ReferenceManyInput> fetches the references for which the target field equals the current record id. You can customize the field that carries the identity of the current record by setting the source prop.

<ReferenceManyInput reference="variants" target="product_id" source="_id">
    ...
</ReferenceManyInput>

sx

You can override the style of the root component (a MUI <FormControl>) and its child components by setting the sx prop.

<ReferenceManyInput
  reference="variants"
  target="product_id"
  sx={{ marginLeft: 2 }}
>
   ...
</ReferenceManyField>

target

Name of the field carrying the relationship on the referenced resource. For instance, if a product has many variants, and each variant resource exposes an product_id field, the target would be author_id.

<ReferenceManyInput reference="variants" target="product_id">
    ...
</ReferenceManyInput>

validate

Just like regular inputs, you can use the validate prop to define custom validation rules for the list of references.

import { minLength } from 'react-admin';

const ProductEdit = () => (
    <Edit mutationMode="optimistic">
        <SimpleForm>
            <TextInput source="name" />
            <ReferenceInput source="category_id" reference="categories" />
            <ReferenceManyInput
                reference="variants"
                target="product_id"
                validate={[minLength(2, 'Please add at least 2 variants')]}
            >
                ...
            </ReferenceManyInput>
        </SimpleForm>
    </Edit>
);

<ReferenceManyToManyField>

This component fetches a list of referenced records by lookup in an associative table and passes the records down to its child component, which must be an iterator component.

Note: The <ReferenceManyToManyField> cannot currently display multiple records with the same id from the end reference resource, even though they might have different properties in the associative table.

For instance, here is how to fetch the authors related to a book record by matching book.id to book_authors.post_id, then matching book_authors.author_id to authors.id, and then displaying the author last_name for each, in a <ChipField>:

import React from 'react';
import {
    Show,
    SimpleShowLayout,
    TextField,
    DateField,
    SingleFieldList,
    ChipField,
} from 'react-admin';
import { ReferenceManyToManyField } from '@react-admin/ra-relationships';

export const BookShow = () => (
    <Show>
        <SimpleShowLayout>
            <TextField source="title" />
            <DateField source="publication_date" />
            <ReferenceManyToManyField
                reference="authors"
                through="book_authors"
                using="book_id,author_id"
            >
                <SingleFieldList>
                    <ChipField source="last_name" />
                </SingleFieldList>
            </ReferenceManyToManyField>
            <EditButton />
        </SimpleShowLayout>
    </Show>
);

import React from 'react';
import {
    Show,
    SimpleShowLayout,
    TextField,
    DateField,
    SingleFieldList,
    ChipField,
} from 'react-admin';
import { ReferenceManyToManyField } from '@react-admin/ra-relationships';

export const BookShow = () => (
    <Show>
        <SimpleShowLayout>
            <TextField source="title" />
            <DateField source="publication_date" />
            <ReferenceManyToManyField
                reference="authors"
                through="book_authors"
                using="book_id,author_id"
            >
                <SingleFieldList>
                    <ChipField source="last_name" />
                </SingleFieldList>
            </ReferenceManyToManyField>
            <EditButton />
        </SimpleShowLayout>
    </Show>
);

<ReferenceManyToManyField> expects an iterator component as child, i.e. a component working inside a ListContext. That means you can use a <Datagrid> instead of a <SingleFieldList> - but not inside another <Datagrid>! This is useful if you want to display a more detailed view of related records. For instance, to display the author first_name and last_name:

export const BookShow = (props) => (
    <Show {...props}>
        <SimpleShowLayout>
            <TextField source="title" />
            <DateField source="publication_date" />
            <ReferenceManyToManyField
                reference="authors"
                through="book_authors"
                using="book_id,author_id"
            >
-               <SingleFieldList>
-                   <ChipField source="last_name" />
-               </SingleFieldList>
+               <Datagrid>
+                   <TextField source="first_name" />
+                   <TextField source="last_name" />
+               </Datagrid>
            </ReferenceManyToManyField>
            <EditButton />
        </SimpleShowLayout>
    </Show>
);

dataProvider Calls

<ReferenceManyToManyField> fetches the dataProvider twice in a row:

• once to get the records of the associative resource (book_authors in this case), using a getManyReference() call
• once to get the records of the reference resource (books in this case), using a getMany() call.

For instance, if the user displays the book of id 123, <ReferenceManyToManyField> first issues the following query to the dataProvider:

dataProvider.getManyReference('book_authors', {
    target: 'book_id',
    id: 123,
});

Let's say that the dataProvider returns the following response:

{
    "data": [
        { "id": 667, "book_id": 123, "author_id": 732 },
        { "id": 895, "book_id": 123, "author_id": 874 }
    ],
    "total": 2
}

Then, <ReferenceManyToManyField> issues a second query to the dataProvider:

dataProvider.getMany('authors', {
    ids: [732, 874],
});

And receives the reference authors:

{
    "data": [
        { "id": 732, "first_name": "John", "last_name": "Doe" },
        { "id": 874, "first_name": "Jane", "last_name": "Doe" }
    ],
    "total": 2
}

Props

Usage

Here is a usage example for these props:

// You can specify the associative table name using the `through` prop.
<ReferenceManyToManyField reference="authors" through="book_authors_assoc">
    {/* ... */}
</ReferenceManyToManyField>

// You can specify the associative table name using the `through` prop.
<ReferenceManyToManyField reference="authors" through="book_authors_assoc">
    {/* ... */}
</ReferenceManyToManyField>

// You can specify the associative table columns using the `using` prop.
<ReferenceManyToManyField
    reference="authors"
    through="book_authors"
    using="b_id,a_id"
>
    {/* ... */}
</ReferenceManyToManyField>

// You can specify the associative table columns using the `using` prop.
<ReferenceManyToManyField
    reference="authors"
    through="book_authors"
    using="b_id,a_id"
>
    {/* ... */}
</ReferenceManyToManyField>

// By default, react-admin restricts the possible values to 25.
// You can change the limit by setting the `perPage` prop:
<ReferenceManyToManyField
    reference="authors"
    through="book_authors"
    using="book_id,author_id"
    perPage={10}
>
    {/* ... */}
</ReferenceManyToManyField>

// By default, react-admin restricts the possible values to 25.
// You can change the limit by setting the `perPage` prop:
<ReferenceManyToManyField
    reference="authors"
    through="book_authors"
    using="book_id,author_id"
    perPage={10}
>
    {/* ... */}
</ReferenceManyToManyField>

// By default, react-admin orders the possible values by `id` desc.
// You can change this order by setting the `sort` prop (an object with `field` and `order` properties)
// to be applied to the associative resource.
<ReferenceManyToManyField
    reference="authors"
    through="book_authors"
    using="book_id,author_id"
    sort={{ field: 'id', order: 'DESC' }}
>
    {/* ... */}
</ReferenceManyToManyField>

// By default, react-admin orders the possible values by `id` desc.
// You can change this order by setting the `sort` prop (an object with `field` and `order` properties)
// to be applied to the associative resource.
<ReferenceManyToManyField
    reference="authors"
    through="book_authors"
    using="book_id,author_id"
    sort={{ field: 'id', order: 'DESC' }}
>
    {/* ... */}
</ReferenceManyToManyField>

// Also, you can filter the records of the associative table using the `filter` prop.
<ReferenceManyToManyField
    reference="authors"
    through="book_authors"
    using="book_id,author_id"
    filter={{ is_public: true }}
>
    {/* ... */}
</ReferenceManyToManyField>

// Also, you can filter the records of the associative table using the `filter` prop.
<ReferenceManyToManyField
    reference="authors"
    through="book_authors"
    using="book_id,author_id"
    filter={{ is_public: true }}
>
    {/* ... */}
</ReferenceManyToManyField>

<ReferenceManyToManyInput>

This component allows adding or removing relationships between two resources sharing an associative table. The changes in the associative table are sent to the dataProvider when the user submits the form so that they can cancel the changes before submission.

Note: The <ReferenceManyToManyInput> cannot currently display multiple records with the same id from the end reference resource even though they might have different properties in the associative table.

For instance, here is how to edit the events related to an artists record through a performances associative table.

┌────────────┐       ┌──────────────┐      ┌────────┐
│ artists    │       │ performances │      │ events │
│------------│       │--------------│      │--------│
│ id         │───┐   │ id           │   ┌──│ id     │
│ first_name │   └──╼│ artist_id    │   │  │ name   │
│ last_name  │       │ event_id     │╾──┘  │        │
└────────────┘       └──────────────┘      └────────┘

In this example, artists.id matches performances.artist_id, and performances.event_id matches events.id. The form displays the events name in a <SelectArrayInput>:

import React from 'react';
import {
    Edit,
    SelectArrayInput,
    SimpleForm,
    TextInput,
    required,
} from 'react-admin';

import { ReferenceManyToManyInput } from '@react-admin/ra-relationships';

const ArtistEdit = () => (
    <Edit>
        <SimpleForm>
            <TextInput disabled source="id" />
            <TextInput source="first_name" />
            <TextInput source="last_name" />
            <ReferenceManyToManyInput
                source="id"
                reference="events"
                through="performances"
                using="artist_id,event_id"
            >
                <SelectArrayInput
                    label="Performances"
                    // Validation must be set on this component
                    validate={required()}
                    optionText="name"
                    fullWidth
                />
            </ReferenceManyToManyInput>
        </SimpleForm>
    </Edit>
);

export default ArtistEdit;

import React from 'react';
import {
    Edit,
    SelectArrayInput,
    SimpleForm,
    TextInput,
    required,
} from 'react-admin';

import { ReferenceManyToManyInput } from '@react-admin/ra-relationships';

const ArtistEdit = () => (
    <Edit>
        <SimpleForm>
            <TextInput disabled source="id" />
            <TextInput source="first_name" />
            <TextInput source="last_name" />
            <ReferenceManyToManyInput
                source="id"
                reference="events"
                through="performances"
                using="artist_id,event_id"
            >
                <SelectArrayInput
                    label="Performances"
                    // Validation must be set on this component
                    validate={required()}
                    optionText="name"
                    fullWidth
                />
            </ReferenceManyToManyInput>
        </SimpleForm>
    </Edit>
);

export default ArtistEdit;

<ReferenceManyToManyInput> expects an input allowing to select multiple values as child - like <SelectArrayInput> in the example above. Other possible children are <AutocompleteArrayInput>, <CheckboxGroupInput>, and <DualListInput>.

dataProvider Calls

When rendered, <ReferenceManyToManyInput> fetches the dataProvider three times in a row:

• once to get the records of the associative resource (performances in this case), using a getManyReference() call
• once to get the records of the reference resource (events in this case), using a getMany() call.
• once to get the possible values of the reference resource (events in this case) to show as suggestions in the input, using a getList() call

For instance, if the user edits the artist of id 123, <ReferenceManyToManyInput> first issues the following query to the dataProvider:

dataProvider.getManyReference('performances', {
    target: 'artist_id',
    id: 123,
});

Let's say that the dataProvider returns the following response:

{
    "data": [
        { "id": 667, "artist_id": 123, "event_id": 732 },
        { "id": 895, "artist_id": 123, "event_id": 874 }
    ],
    "total": 2
}

Then, <ReferenceManyToManyInput> issues a second query to the dataProvider:

dataProvider.getMany('events', {
    ids: [732, 874],
});

Which returns the following:

{
    "data": [
        { "id": 732, "name": "Acme Rock Festival" },
        { "id": 874, "name": "Roll and Rock 2020" }
    ]
}

That's enough to display the current value in the input. But to display events suggestions, the component makes a final call:

dataProvider.getList('events', {
    sort: { field: 'id', order: 'DESC' },
    pagination: { page: 1, perPage: 25 },
    filter: {},
});

{
    "data": [
        { "id": 1, "name": "Rock Your Town" },
        { "id": 2, "name": "Aime le Rock" },
        { "id": 3, "name": "Breed Festival" },
        ...
    ],
    "total": 32
}

And that's it for the display phase.

When the user submits the form, the save function compares the value of the <ReferenceManyToManyInput> (the list of relationships edited by the user) with the value previously returned by the dataProvider. Using a diffing algorithm, it deduces a list of insertions and deletions in the associative table, that are executed all at once.

For instance, let's say that after displaying the events 732 and 874 where artist 123 performs, the user removes event 732, and adds events 2 and 3. Upon submission, the dataProvider will detect removals and additions, and send the following queries:

dataProvider.delete('performances', {
    id: 667,
    previousData: { id: 667, artist_id: 123, event_id: 732 },
});
dataProvider.create('performances', {
    data: { artist_id: 123, event_id: 2 },
});
dataProvider.create('performances', {
    data: { artist_id: 123, event_id: 3 },
});

Props

<DualListInput>

To let users choose multiple values by moving them from a list of available choices to a list of selected choices, use a <DualListInput>. It renders using two MUI's <List>. Set the choices prop to determine the options (with id, name tuples):

const choices = [
    { id: 'programming', name: 'Programming' },
    { id: 'lifestyle', name: 'Lifestyle' },
    { id: 'photography', name: 'Photography' },
];
<DualListInput source="tags" choices={choices} />;

const choices = [
    { id: 'programming', name: 'Programming' },
    { id: 'lifestyle', name: 'Lifestyle' },
    { id: 'photography', name: 'Photography' },
];
<DualListInput source="tags" choices={choices} />;

Props

Usage

You can customize the properties to use for the option name and value, thanks to the optionText and optionValue attributes:

const choices = [
    { _id: 123, full_name: 'Leo Tolstoi' },
    { _id: 456, full_name: 'Jane Austen' },
];
<DualListInput
    source="authors_ids"
    choices={choices}
    optionText="full_name"
    optionValue="_id"
/>;

const choices = [
    { _id: 123, full_name: 'Leo Tolstoi' },
    { _id: 456, full_name: 'Jane Austen' },
];
<DualListInput
    source="authors_ids"
    choices={choices}
    optionText="full_name"
    optionValue="_id"
/>;

optionText also accepts a function, so you can shape the option text at will:

const choices = [
    { id: 123, first_name: 'Leo', last_name: 'Tolstoi' },
    { id: 456, first_name: 'Jane', last_name: 'Austen' },
];
const optionRenderer = choice => `${choice.first_name} ${choice.last_name}`;
<DualListInput
    source="authors_ids"
    choices={choices}
    optionText={optionRenderer}
/>;

const choices = [
    { id: 123, first_name: 'Leo', last_name: 'Tolstoi' },
    { id: 456, first_name: 'Jane', last_name: 'Austen' },
];
const optionRenderer = choice => `${choice.first_name} ${choice.last_name}`;
<DualListInput
    source="authors_ids"
    choices={choices}
    optionText={optionRenderer}
/>;

optionText also accepts a React Element, that will be cloned and receive the related choice as the record prop. You can use Field components there.

const choices = [
    { id: 123, first_name: 'Leo', last_name: 'Tolstoi' },
    { id: 456, first_name: 'Jane', last_name: 'Austen' },
];
const FullNameField = ({ record }) => (
    <span>
        {record.first_name} {record.last_name}
    </span>
);
<DualListInput
    source="authors_ids"
    choices={choices}
    optionText={<FullNameField />}
/>;

const choices = [
    { id: 123, first_name: 'Leo', last_name: 'Tolstoi' },
    { id: 456, first_name: 'Jane', last_name: 'Austen' },
];
const FullNameField = ({ record }) => (
    <span>
        {record.first_name} {record.last_name}
    </span>
);
<DualListInput
    source="authors_ids"
    choices={choices}
    optionText={<FullNameField />}
/>;

The choices are translated by default, so you can use translation identifiers as choices:

const choices = [
    { id: 1, name: 'permissions.users.write' },
    { id: 2, name: 'permissions.users.read' },
    { id: 3, name: 'permissions.users.delete' },
];

const choices = [
    { id: 1, name: 'permissions.users.write' },
    { id: 2, name: 'permissions.users.read' },
    { id: 3, name: 'permissions.users.delete' },
];

However, in some cases, you may not want the choice to be translated. In that case, set the translateChoice prop to false.

<DualListInput source="permissions" choices={choices} translateChoice={false} />

<DualListInput source="permissions" choices={choices} translateChoice={false} />

Note that translateChoice is set to false when <DualListInput> is a child of <ReferenceArrayInput>.

Tip: If you want to populate the choices attribute with a list of related records, you should decorate <DualListInput> with <ReferenceArrayInput>, and leave the choices empty:

import { ReferenceArrayInput } from 'react-admin';
import { DualListInput } from '@react-admin/ra-relationships';

<ReferenceArrayInput label="Authors" source="authors_ids" reference="authors">
    <DualListInput optionText="last_name" />
</ReferenceArrayInput>;

import { ReferenceArrayInput } from 'react-admin';
import { DualListInput } from '@react-admin/ra-relationships';

<ReferenceArrayInput label="Authors" source="authors_ids" reference="authors">
    <DualListInput optionText="last_name" />
</ReferenceArrayInput>;

You can set disabled values by setting the disabled property of one item:

const choices = [
    { _id: 123, full_name: 'Leo Tolstoi' },
    { _id: 456, full_name: 'Jane Austen' },
    { _id: 1, full_name: 'System Administrator', disabled: true },
];
<DualListInput
    source="authors_ids"
    choices={choices}
    optionText="full_name"
    optionValue="_id"
/>;

const choices = [
    { _id: 123, full_name: 'Leo Tolstoi' },
    { _id: 456, full_name: 'Jane Austen' },
    { _id: 1, full_name: 'System Administrator', disabled: true },
];
<DualListInput
    source="authors_ids"
    choices={choices}
    optionText="full_name"
    optionValue="_id"
/>;

You can use a custom field name by setting disableValue prop:

const choices = [
    { _id: 123, full_name: 'Leo Tolstoi' },
    { _id: 456, full_name: 'Jane Austen' },
    { _id: 987, full_name: 'Jack Harden', not_available: true },
];
<DualListInput
    source="contacts_ids"
    choices={choices}
    optionText="full_name"
    optionValue="_id"
    disableValue="not_available"
/>;

const choices = [
    { _id: 123, full_name: 'Leo Tolstoi' },
    { _id: 456, full_name: 'Jane Austen' },
    { _id: 987, full_name: 'Jack Harden', not_available: true },
];
<DualListInput
    source="contacts_ids"
    choices={choices}
    optionText="full_name"
    optionValue="_id"
    disableValue="not_available"
/>;

Buttons can be customized through the addButton and removeButton props to fit the look and feel of your application. You have 3 options:

• provide a MUI button variant value (outlined, contained or text)
• leave it undefined to use the theme defaults
• pass a React element. In this case, react-admin will clone the element and provide it with a disabled and onClick prop.