Application Configuration Files¶

Overview¶

MongoDB Realm uses JSON files and source code files to define and configure every component of an application. Each component has a specific configuration file schema and every application uses a standard file structure to organize the configuration files.

When Will I Use Configuration Files?¶

Every Realm app is composed of a collection of configuration files, so you use application configuration files whenever you create or modify a Realm app. If you use the Realm UI then you rarely deal directly with the configuration files themselves, but other deployment methods, like Realm CLI and GitHub allow you to define and edit the configuration files directly.

Directory Structure¶

The following figure shows a high-level view of a Realm app's directory structure:

yourRealmApp/
├── config.json
├── secrets.json
├── auth_providers/
│   └── <provider name>.json
├── functions/
│   └── <function name>/
│       ├── config.json
│       └── source.js
├── services/
│   └── <service name>/
│       ├── config.json
│       ├── incoming_webhooks/
│       │   ├── config.json
│       │   └── source.js
│       └── rules/
│           └── <rule name>.json
├── triggers/
│   └── <trigger name>.json
├── hosting/
│   ├── metadata.json
│   └── files/
│       └── <files to host>
└── values/
    └── <value name>.json

Application Configuration¶

Application-level configuration information is defined in a single document named config.json stored in your application's root directory.

yourRealmApp/
└── config.json

Configuration¶

config.json

{
  "app_id": "",
  "name": "",
  "security": {
    "allowed_request_origins": ["<Origin URL>"]
  },
  "hosting": {
    "enabled": <boolean>,
    "custom_domain": "<Custom Domain Name>",
    "app_default_domain": "<Default Domain Name>"
  },
  "custom_user_data_config": {
    "enabled": <Boolean>
    "mongo_service_id": "<MongoDB Service ID>",
    "database_name": "<Database Name>",
    "collection_name": "<Collection Name>",
    "user_id_field": "<Field Name>"
  }
  "deployment_model": "<Deployment Model Type>",
  "location": "<Deployment Cloud Region Name>",
  "config_version": <Version Number>
}

Field Description

app_id

String

The application's App ID.

name

String

The application's name.

Note

App Name Limitations

Application names must be between 1 and 32 characters and may only contain ASCII letters, numbers, underscores, and hyphens.

security

Document

A document that contains configuration options for application-level security features.

"security": {
  "allowed_request_origins": ["<Origin URL>"]
}

Field Name Description

allowed_request_origins

Array<String>

An array of URLs that incoming requests may originate from. If you define any allowed request origins, then Realm blocks any incoming request from an origin that is not listed.

Request origins are URLs with the following form:

<scheme>://<host>[:port]

hosting

Document

A document that contains configuration options for all hosted files:

"hosting": {
  "enabled": <boolean>,
  "custom_domain": "<Custom Domain Name>",
  "app_default_domain": "<Default Domain Name>"
}

Field Name	Description
`enabled` Boolean	If `true`, indicates that your application can host static files.
`custom_domain` String	A custom domain name for your application's hosted files.
`app_default_domain` String	The default domain for your application's hosted files. Realm automatically sets this value and you cannot change it.

config_version

Number

The schema version that all configuration files in the application conform to. This value is machine generated and you typically should not manually set or modify it.

custom_user_data_config

Document

A document that contains configuration options for custom user data.

"custom_user_data_config": {
  "enabled": <Boolean>
  "mongo_service_id": "<MongoDB Service ID>",
  "database_name": "<Database Name>",
  "collection_name": "<Collection Name>",
  "user_id_field": "<Field Name>"
}

Field Name	Description
`enabled` Boolean	If `true`, Realm associates each user with a document that contains their data stored in the specified collection.
`mongo_service_id` String	The service ID of the linked MongoDB Atlas data source that contains the custom user data. You can find this value in the `id` field of the service configuration file.
`database_name` String	The name of the database that contains the custom user data collection.
`collection_name` String	The name of the collection that contains the custom user data.
`user_id_field` String	The name of the field in each custom data document that contains the user ID of the application user the document describes.

deployment_model

String

The application's deployment model. The following values are valid:

Deployment Model	Value
Global Deployment	`"GLOBAL"`
Local Deployment	`"LOCAL"`

location

String

The name of the cloud region that the application is deployed in.

Local applications process all
application requests and database writes in this region.
Global applications process all database writes in this region, but serve other application requests in the nearest deployment region.

Authentication Providers¶

Authentication providers are defined in your application's /auth_providers directory.

Each provider is defined in its own JSON file named after the provider. For detailed information on configuring and using a specific authentication provider, see that provider's reference page.

yourRealmApp/
└── auth_providers/
    └── <provider name>.json

Configuration¶

<provider name>.json

{
  "id": "<Provider ID>",
  "name": "<Provider Name>",
  "type": "<Provider Type>",
  "disabled": <Boolean>,
  "config": {
    "<Configuration Option>": <Configuration Value>
  },
  "secret_config": {
    "<Configuration Option>": "<Secret Name>"
  },
  "metadata_fields": [{
    "required": <Boolean>,
    "name": "Field Name"
  }]
}

Field	Description
`id` String	A value that uniquely identifies the authentication provider. Realm automatically generates a unique ID for a provider when you create it.
`name` String	The name of the authentication provider.
`type` String	The type of the authentication provider. Valid Options: `"anon-user"` `"local-userpass"` `"api-key"` `"oauth2-apple"` `"oauth2-google"` `"oauth2-facebook"` `"custom-token"` `"custom-function"`
`config` Document	A document that contains configuration values that are specific to the authentication provider. The existence of this field and its exact configuration fields depend on the provider type.
`secret_config` Document	A document where each field name is a private configuration field for the provider and the value of each field is the name of a Secret that stores the configuration value.
`metadata_fields` Array<Document>	An array of documents where each document defines a metadata field that describes the user. The existence of this field and the exact format of each metadata field document depends on the provider type.
`disabled` Boolean	If `true`, this authentication provider is not enabled for your application and cannot be used.

Functions¶

Realm Functions are defined in a sub-directory of your application's /functions directory. Each function maps to its own subdirectory with the same name as the function.

Each function is configured in config.json and has its source code defined in source.js.

yourRealmApp/
└── functions/
    └── <function name>/
        ├── config.json
        └── source.js

Configuration¶

config.json

{
  "id": "<Function ID>",
  "name": "<Function Name>",
  "private": <Boolean>,
  "can_evaluate": <Rule Expression>,
  "disable_arg_logs": <Boolean>,
  "run_as_system": <Boolean>,
  "run_as_user_id": "<Realm User ID>",
  "run_as_user_id_script_source": "<Function Source Code>"
}

Field	Description
`id` String	A value that uniquely identifies the function. Realm automatically generates a unique ID for a function when you create it.
`name` String	The name of the function. The name must be unique among all functions in your application.
`private` Boolean	If `true`, this function may only be accessed from incoming webhooks, rules, and named functions.
`can_evaluate` Document	A rule expression that evaluates to `true` when the function is allowed to execute in response to a given request.
`disable_arg_logs` Boolean	If `true`, Realm omits the arguments provided to a function from the function execution log entry.
`run_as_system` Boolean	If `true`, this function runs as the system user. This overrides any values defined for `run_as_user_id` and `run_as_user_id_script_source`.
`run_as_user_id` String	The unique ID of a Realm User that the function always executes as. Cannot be used with `run_as_user_id_script_source`.
`run_as_user_id_script_source` String	A stringified function that runs whenever the function is called and returns the unique ID of a Realm User that the function executes as. Cannot be used with `run_as_user_id`.

Source Code¶

source.js

exports = function() {
  // function code
};

MongoDB Services¶

Every MongoDB Atlas data source linked to your app is configured as a service in the /services directory. Each data source maps to its own sub-directory with the same name as the service.

The primary service configuration for a MongoDB Atlas data source is config.json, which defines connection parameters and sync rules.

If the data source is not a synced cluster or Data Lake, then you can define collection-level rules in the /rules sub-directory.

yourRealmApp/
└── services/
    └── <MongoDB Service Name>/
        ├── config.json
        └── rules/
            └── <rule name>.json

Important

MongoDB Service names are not necessarily the same as their linked data source's name in Atlas. You define the service name for a data source when you link it to your application. For linked clusters, the default MongoDB service name is mongodb-atlas. For linked Data Lakes, the default service name is mongodb-datalake.

Service Configuration¶

The configuration file to link an Atlas cluster should have the following form:

config.json

{
  "id": "<Service ID>",
  "name": "<Service Name>",
  "type": "mongodb-atlas",
  "config": {
    "clusterName": "<Atlas Cluster Name>",
    "readPreference": "<Read Preference>",
    "wireProtocolEnabled": <Boolean>,
    "sync": <Sync Configuration>
  }
}

The configuration file to link a Data Lake should have the following form:

config.json

{
  "id": "<Service ID>",
  "name": "<Service Name>",
  "type": "datalake",
  "config": {
     "dataLakeName": "<Data Lake>"
   }
 }

Exactly one of config.dataLakeName and config.clusterName is required, depending on whether you are linking a Data Lake or a cluster.

Field Description

id

String

A string that uniquely identifies the service. Realm automatically generates a unique ID for a MongoDB service when you create it.

name

String

The name of the service. The name may be at most 64 characters long and can only contain ASCII letters, numbers, underscores, and hyphens. For clusters, the default name is mongodb-atlas. For Data Lakes, it is mongodb-datalake.

type

String

For MongoDB Atlas clusters, this value is always "mongodb-atlas". For Data Lakes, this value is "datalake".

config.clusterName

String

Required when linking a cluster. The name of the service's linked cluster in MongoDB Atlas.

config.dataLakeName

String

Required when linking a Data Lake. The name of the Data Lake that you want to link to your application.

config.readPreference

String

The read preference mode for queries sent through the service. Not available for Data Lakes.

Mode	Description
primary	Realm routes all read operations to the current replica set primary node. This is the default read preference mode.
primaryPreferred	Realm routes all read operations to the current replica set primary node if it's available. If the primary is unavailable, such as during an automatic failover, read requests are routed to a secondary node instead.
secondary	Realm routes all read operations to one of the current replica set secondary nodes.
secondaryPreferred	Realm routes all read operations to one of the replica set's available secondary nodes. If no secondary is available, read requests are routed to the replica set primary instead.
nearest	Realm routes read operations to the replica set member that has the lowest network latency relative to the client.

config.sync

Document

A configuration document that determines if a cluster is synced and, if it is, defines the rules for sync operations on the cluster. Not available for Data Lakes.

For detailed information on sync configuration documents, see Synced Cluster Configuration.

Synced Cluster Configuration¶

The config.sync field of config.json determines if a cluster is synced and, if it is, defines the rules for sync operations on the cluster.

config.json

{
  ...,
  "config": {
    ...,
    "sync": {
      "state": <Boolean>,
      "development_mode_enabled": <Boolean>,
      "database_name": "<Developer Mode Database Name>",
      "partition": {
        "key": "<Partition Key Field Name>",
        "type": "<Partition Key Value Type>",
        "permissions": {
          "read": <JSON Expression>,
          "write": <JSON Expression>
        }
      }
    }
  }
}

Field	Description
`sync.state` Boolean	If `true`, Sync is enabled for the cluster, which means that client applications can sync data in the cluster with Realm Database and that non-sync collection rules do not apply.
`sync.development_mode_enabled` Boolean	If `true`, development mode is enabled for the cluster. While enabled, Realm does not enforce sync rules, stores synced objects in a specific database within the cluster, and mirrors object types in that database's collection schemas.
`sync.database_name` String	The name of the database in the synced cluster where Realm should store synced objects. When development mode is enabled, Realm stores synced objects in this database. Each object type maps to its own collection in the database with a schema that matches the synced objects.
`sync.partition.key` String	The name of the field that partitions data into client Realms.
`sync.partition.type` String	The type of the partition key field value.
`sync.partition.permissions` Document	A document that defines the `read` and `write` permissions for the synced cluster. Permissions are defined with rule expressions that Realm evaluates per-user, per-partition. The expressions have access to the `%%user` and `%%partition` expansions.

MongoDB Collection Rules (Non-Sync)¶

For non-synced clusters, you can define collection-level rules that Realm evaluates dynamically for each request. Each collection's rules are stored in the /rules sub-directory in a JSON file with the same name as the collection namespace.

Note

Data Lake data sources do not support rules. You can only access a Data Lake data source in a system function.

<database.collection>.json

{
  "id": "<Rule ID>",
  "database": "<Database Name>",
  "collection": "<Collection Name>",
  "roles": [<Query Role>],
  "schema": <Document Schema>,
  "filters": [<Query Filter>],
}

Field Description

id

String

A string that uniquely identifies the trigger. Realm automatically generates a unique ID for a trigger when you create it.

database

String

The name of the database that holds the collection.

collection

String

The name of the collection.

roles

Array<Document>

An array of Query Role configuration documents, which have the following form:

{
   "name": "<Role Name>",
   "apply_when": <JSON Expression>,
   "insert": <Boolean|JSON Expression>,
   "delete": <Boolean|JSON Expression>,
   "read": <Boolean|JSON Expression>,
   "write": <Boolean|JSON Expression>,
   "search": <Boolean|JSON Expression>,
   "fields": {
      "<Field Name>": {
         "read": <Boolean|JSON Expression>,
         "write": <Boolean|JSON Expression>,
         "fields": <Fields Document>
      },
      ...
   },
   "additional_fields": {
     "read": <Boolean|JSON Expression>,
     "write": <Boolean|JSON Expression>
   },
}

Field Description

name

String

The name of the role. Role names are useful for identifying and distinguishing between roles. Limited to 100 characters or fewer.

apply_when

Document

A JSON Expression that evaluates to true when this role should be applied.

read
Boolean or Document
Default: false

A boolean or JSON Expression that evaluates to true if the role has permission to read all fields in the document.

Document-level read permissions take priority over any field-level permissions. If a role has a document-level read rule, it applies to all fields in the document and cannot be overridden. To define specific field-level rules with a default fallback, use additional_fields instead.

write
Boolean or Document
Default: false

A boolean or JSON Expression that evaluates to true if the role has permission to add, modify, or remove all fields in the document.

Document-level write permissions take priority over any field-level permissions. If a role has a document-level write rule, it applies to all fields in the document and cannot be overridden. To define specific field-level rules with a default fallback, use additional_fields instead.

Important

Implicit Read Permission

Any time a role has write permission for a particular scope it also has read permission even if that is not explicitly defined.

Note

MongoDB Expansions

You can use MongoDB expansions, like %%root and %%prevRoot, in write JSON expressions.

insert
Boolean or Document
Default: true

A boolean or JSON Expression that evaluates to true if the role has permission to insert a new document into the collection.

Note

Document-level insert permission does not imply that a role can insert any document. The role must also have write permission for all fields in an inserted document for the insert to succeed.

delete
Boolean or Document
Default: true

A boolean or JSON Expression that evaluates to true if the role has permission to delete a document from the collection.

search
Boolean or Document
Default: true

A boolean or JSON Expression that evaluates to true if the role has permission to search the collection using Atlas Search.

Important

Realm performs $search operations as a system user and enforces field-level rules on the returned search results. This means that a user may search on a field for which they do not have read access. In this case, the search is based on the specified field but no returned documents include the field.

fields
Document
Default: {}

A document where the value of each field defines the role's field-level read and write permissions for the corresponding field in a queried document.

"fields": {
  "<Field Name>": {
     "read": <Boolean|JSON Expression>,
     "write": <Boolean|JSON Expression>,
     "fields": <Fields Document>
  },
  ...
}

Note

Permission Priority

Document-level read or write permissions override all field-level permissions of the same type. If permissions are defined for a field that contains an embedded document, those permissions override any permissions defined for the document's embedded fields.

fields.<Field Name>.read
Boolean or Document
Default: false

A boolean or JSON Expression that evaluates to true if the role has permission to read the field.

fields.<Field Name>.write
Boolean or Document
Default: false

A boolean or JSON Expression that evaluates to true if the role has permission to add, modify, or remove the field.

fields.<Field Name>.fields
Document
Default: {}

A fields document that defines read and write permissions for fields that are embedded within this field in a queried document.

See the Field-level Permissions for Embedded Documents role pattern for more information.

additional_fields
Document
Default: {}

A document that defines the role's field-level read and write permissions for any fields in a queried document that don't have explicitly defined permissions.

"additional_fields": {
  "read": <Boolean|JSON Expression>,
  "write": <Boolean|JSON Expression>
}

additional_fields.read
Boolean or Document
Default: false

A boolean or JSON Expression that evaluates to true if the role has permission to read any field that does not have a field-level permission definition.

additional_fields.write
Boolean or Document
Default: false

A boolean or JSON Expression that evaluates to true if the role has permission to add, modify, or remove any field that does not have a field-level permission definition.

schema

Document

A Document Schema. The root level schema must be an object schema, which has the following form:

{
  "bsonType": "object",
  "properties": {
    "<Field Name>": <Schema Document>
  }
}

filters

Array<Document>

An array of Query Filter configuration documents, which have the following form:

{
  "name": "<Filter Name>",
  "apply_when": <JSON Expression>,
  "query": <Query Document>,
  "projection": <Projection Document>
}

Field Description

name

String

Required. The name of the filter. Filter names are useful for identifying and distinguishing between filters. Limited to 100 characters or fewer.

apply_when

Required. A JSON expression that determines when this filter applies to a given query.

Important

MongoDB Realm evaluates and applies filters before it reads any documents, so you cannot use MongoDB document expansions in a filter's Apply When expression. However, you can use other expression variables, such as %%user, %%values, and %function.

query

Document

Required. A MongoDB query filter that contains additional query predicates to merge into incoming queries that the filter applies to.

Example

A filter that withholds documents that have a score below 20 could use the following filter query:

{ "score": { "$gt": 20 } }

projection

Document

Required. A MongoDB projection document that specifies additional field projections to merge into incoming queries that the filter applies to.

Important

Projection Conflicts

MongoDB projections can be either inclusive or exclusive, i.e. they can either return only specified fields or withhold fields that are not specified. If multiple filters apply to a query, the filters must all specify the same type of projection, or the query will fail.

Example

A filter that withholds the _internal field from all documents could use the following filter projection:

{ "_internal": 0 }

External Services¶

3rd party services are defined in the /services directory. Each service maps to its own sub-directory with the same name as the service.

Each service directory contains the following:

config.json: a service configuration file
/rules: a sub-directory of service rule configurations
/incoming_webhooks: a sub-directory of webhook configurations (if the service supports webhooks, i.e. HTTP, GitHub, or Twilio)

yourRealmApp/
└── services/
    └── <services name>/
        ├── config.json
        ├── incoming_webhooks/
        │   ├── config.json
        │   └── source.js
        └── rules/
            └── <rule name>.json

Service Configuration¶

config.json

{
  "id": "<Service ID>",
  "name": "<Service Name>",
  "type": "<Service Type>",
  "config": {
    "<Configuration Option>": <Configuration Value>
  },
  "secret_config": {
    "<Configuration Option>": "<Secret Name>"
  },
}

Field	Description
`id` String	A string that uniquely identifies the service. Realm automatically generates a unique ID for a service when you create it.
`name` String	The name of the service. The name may be at most 64 characters long and can only contain ASCII letters, numbers, underscores, and hyphens.
`type` String	The type of the service. Valid Options: `"http"` `"aws"` `"twilio"` `"github"` `"gcm"`
`config` Document	A document with fields that map to additional configuration options for the service. The exact configuration fields depend on the service `type`. HTTP Service Configuration AWS Service Configuration Twilio Service Configuration GitHub Service Configuration
`secret_config` Document	A document where each field name is a private configuration field for the service and the value of each field is the name of a Secret that stores the configuration value.

Service Rules¶

Rules for a specific external service are defined in the /<service name>/rules sub-directory.

Each rule maps to its own JSON file with the same name as the rule.

<rule name>.json

{
  "id": "<Rule ID>",
  "name": "<Rule Name>",
  "actions": ["<Service Action Name>"],
  "when": <JSON Rule Expression>
}

Field	Description
`id` String	A string that uniquely identifies the rule. Realm automatically generates a unique ID for a rule when you create it.
`name` String	The name of the service rule. The name may be at most 64 characters long and can only contain ASCII letters, numbers, underscores, and hyphens.
`actions` Array<String>	A list of service actions that the rule applies to. The specific actions available depend on the service `type`.
`when` Document	A rule expression that evaluates to `true` when the rule applies to a given request.

Incoming Webhooks¶

Incoming webhooks for a specific service are defined in the /<service name>/incoming_webhooks/ sub-directory.

Incoming webhooks use the same configuration format as function but have additional configuration parameters.

Configuration¶

config.json

{
  "id": "<Function ID>",
  "name": "<Function Name>",
  "private": <Boolean>,
  "can_evaluate": <Rule Expression>,
  "disable_arg_logs": <Boolean>,
  "run_as_system": <Boolean>,
  "run_as_user_id": "<Realm User ID>",
  "run_as_user_id_script_source": "<Function Source Code>",
  "respond_result": <Boolean>,
  "options": {
    "httpMethod": "<HTTP Method>",
    "validationMethod": "<Webhook Validation Method>",
    "secret": "<Webhook Secret>"
  }
}

Field Description

id

String

A value that uniquely identifies the function. Realm automatically generates a unique ID for a function when you create it.

name

String

The name of the function. The name must be unique among all functions in your application.

private

Boolean

If true, this function may only be accessed from incoming webhooks, rules, and named functions.

can_evaluate

Document

A rule expression that evaluates to true when the function is allowed to execute in response to a given request.

disable_arg_logs

Boolean

If true, Realm omits the arguments provided to a function from the function execution log entry.

run_as_system

Boolean

If true, the webhook function runs as the system user. This overrides any values defined for run_as_user_id and run_as_user_id_script_source.

run_as_user_id

String

The unique ID of a Realm User that the function always executes as. Cannot be used with run_as_user_id_script_source.

run_as_user_id_script_source

String

A stringified function that runs whenever the webhook is called and returns the unique ID of a Realm User that the function executes as. Cannot be used with run_as_user_id.

respond_result

Boolean

If true, Realm includes the webhook function return value as the body of the HTTP response it sends to the client that initiated the webhook request.

options

Document

A document that contains configuration options for the webhook.

{
  "httpMethod": "<HTTP Method>",
  "validationMethod": "<Webhook Validation Method>",
  "secret": "<Webhook Secret>"
}

Field Description

httpMethod

String

The HTTP method type that the webhook accepts. Incoming webhook requests must use this method.

validationMethod

String

The name of the request validation method that the webhook uses.

Valid options:

"VERIFY_PAYLOAD"
"SECRET_AS_QUERY_PARAM"
"NO_VALIDATION"

secret

String

The secret value used to validate incoming webhook requests.

Source Code¶

source.js

exports = function() {
  // webhook function code
};

Triggers¶

Triggers are defined in your application's /triggers directory.

Each trigger is defined in its own JSON file with the same name as the trigger.

yourRealmApp/
└── triggers/
    └── <trigger name>.json

Configuration¶

<trigger name>.json

{
  "id": "<Trigger ID>",
  "name": "<Trigger Name>",
  "type": "<Trigger Type>",
  "function_name": "<Trigger Function Name>",
  "config": {
    "<Configuration Option>": <Configuration Value>
  },
  "disabled": <Boolean>,
}

Field	Description
`id` String	A string that uniquely identifies the Trigger. Realm automatically generates a unique ID for a trigger when you create it.
`name` String	The name of the Trigger. The name may be at most 64 characters long and can only contain ASCII letters, numbers, underscores, and hyphens.
`type` String	The type of application event that the trigger listens for. Valid Options: `"DATABASE"` `"AUTHENTICATION"` `"SCHEDULED"`
`function_name` String	The name of the Realm Function that the Trigger executes whenever it fires. The Trigger automatically passes arguments to the function depending on the Trigger `type`.
`config` Document	A document with fields that map to additional configuration options for the trigger. The exact configuration fields depend on the trigger `type`. Database Trigger Configuration Authentication Trigger Configuration Scheduled Trigger Configuration
`disabled` Boolean	If `true`, the trigger will not listen for any events and will not fire.

Hosting¶

Files that you want to host on Realm should be included in your application's /hosting directory. Each file will be uploaded with the metadata defined in metadata.json.

You can configure the metadata for each hosted file in metadata.json. This metadata configuration file is an array of documents that each correspond to a single hosted file's metadata attributes.

yourRealmApp/
└── hosting/
    ├── metadata.json
    └── files/
        └── <files to host>

Metadata Configuration¶

metadata.json

[
  {
    "path": "<File Resource Path>",
    "attrs": [{
      "name": "<Attribute Type>",
      "value": "<Attribute Value>"
    }]
  }
]

Field Description

path

String

The resource path of the file.

attrs

Array<Document>

An array of documents where each document represents a single metadata attribute. Attribute documents have the following form:

Metadata Attribute Document

{
  "name": "<Attribute Type>",
  "value": "<Attribute Value>"
}

Field	Description
`name` String	The name of the metadata attribute. This should be one of the file metadata attributes that Realm supports.
`value` String	The value of the metadata attribute.

Note

If you do not specify a Content-Type attribute for a file, MongoDB Realm will attempt to automatically add a Content-Type attribute to it based on the file extension.

For example, Realm would automatically add the attribute Content-Type: application/html to the file myPage.html.

Values¶

Values are defined in your application's /values directory.

Each value is defined in its own JSON file named after the value.

yourRealmApp/
└── values/
    └── <value name>.json

Configuration¶

<value name>.json

{
  "id": "<Value ID>",
  "name": "<Value Name>",
  "from_secret": <boolean>,
  "value": <Stored JSON Value|Secret Name>
}

Field	Description
`id` String	A string that uniquely identifies the value. Realm automatically generates a unique ID for a value when you create it.
`name` String	A unique name for the value. This name is how you refer to the value in functions and rules.
`from_secret` Boolean	Default: `false`. If `true`, the value exposes a Secret instead of a plain-text JSON value.
`value` String, Array, or Object	The stored data that Realm exposes when the value is referenced. If `from_secret` is `false`, `value` can be a standard JSON string, array, or object. If `from_secret` is `true`, `value` is a string that contains the name of the Secret that the value exposes.

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