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title titleSuffix description author ms.service ms.subservice ms.custom ms.topic ms.date ms.author
Copy and transform data from and to a REST endpoint by using Azure Data Factory
Azure Data Factory & Azure Synapse
Learn how to use Copy Activity to copy data and use Data Flow to transform data from a cloud or on-premises REST source to supported sink data stores, or from supported source data store to a REST sink in Azure Data Factory or Azure Synapse Analytics pipelines.
jianleishen
data-factory
data-movement
synapse
conceptual
06/07/2022
makromer

Copy and transform data from and to a REST endpoint by using Azure Data Factory

[!INCLUDEappliesto-adf-asa-md]

This article outlines how to use Copy Activity in Azure Data Factory to copy data from and to a REST endpoint. The article builds on Copy Activity in Azure Data Factory, which presents a general overview of Copy Activity.

The difference among this REST connector, HTTP connector, and the Web table connector are:

  • REST connector specifically supports copying data from RESTful APIs.
  • HTTP connector is generic to retrieve data from any HTTP endpoint, for example, to download file. Before this REST connector you may happen to use HTTP connector to copy data from RESTful APIs, which is supported but less functional comparing to REST connector.
  • Web table connector extracts table content from an HTML webpage.

Supported capabilities

You can copy data from a REST source to any supported sink data store. You also can copy data from any supported source data store to a REST sink. For a list of data stores that Copy Activity supports as sources and sinks, see Supported data stores and formats.

Specifically, this generic REST connector supports:

  • Copying data from a REST endpoint by using the GET or POST methods and copying data to a REST endpoint by using the POST, PUT or PATCH methods.
  • Copying data by using one of the following authentications: Anonymous, Basic, AAD service principal, and user-assigned managed identity.
  • Pagination in the REST APIs.
  • For REST as source, copying the REST JSON response as-is or parse it by using schema mapping. Only response payload in JSON is supported.

Tip

To test a request for data retrieval before you configure the REST connector in Data Factory, learn about the API specification for header and body requirements. You can use tools like Postman or a web browser to validate.

Prerequisites

[!INCLUDE data-factory-v2-integration-runtime-requirements]

Get started

[!INCLUDE data-factory-v2-connector-get-started]

Create a REST linked service using UI

Use the following steps to create a REST linked service in the Azure portal UI.

  1. Browse to the Manage tab in your Azure Data Factory or Synapse workspace and select Linked Services, then click New:

    Azure Data Factory

    :::image type="content" source="media/doc-common-process/new-linked-service.png" alt-text="Screenshot of creating a new linked service with Azure Data Factory UI.":::

    Azure Synapse

    :::image type="content" source="media/doc-common-process/new-linked-service-synapse.png" alt-text="Screenshot of creating a new linked service with Azure Synapse UI.":::

  2. Search for REST and select the REST connector.

    :::image type="content" source="media/connector-rest/rest-connector.png" alt-text="Select REST connector.":::

  3. Configure the service details, test the connection, and create the new linked service.

    :::image type="content" source="media/connector-rest/configure-rest-linked-service.png" alt-text="Configure REST linked service.":::

Connector configuration details

The following sections provide details about properties you can use to define Data Factory entities that are specific to the REST connector.

Linked service properties

The following properties are supported for the REST linked service:

Property Description Required
type The type property must be set to RestService. Yes
url The base URL of the REST service. Yes
enableServerCertificateValidation Whether to validate server-side TLS/SSL certificate when connecting to the endpoint. No
(the default is true)
authenticationType Type of authentication used to connect to the REST service. Allowed values are Anonymous, Basic, AadServicePrincipal, and ManagedServiceIdentity. User-based OAuth isn't supported. You can additionally configure authentication headers in authHeader property. Refer to corresponding sections below on more properties and examples respectively. Yes
authHeaders Additional HTTP request headers for authentication.
For example, to use API key authentication, you can select authentication type as “Anonymous” and specify API key in the header.		 No
connectVia The Integration Runtime to use to connect to the data store. Learn more from Prerequisites section. If not specified, this property uses the default Azure Integration Runtime. No

Use basic authentication

Set the authenticationType property to Basic. In addition to the generic properties that are described in the preceding section, specify the following properties:

Property Description Required
userName The user name to use to access the REST endpoint. Yes
password The password for the user (the userName value). Mark this field as a SecureString type to store it securely in Data Factory. You can also reference a secret stored in Azure Key Vault. Yes

Example

{
    "name": "RESTLinkedService",
    "properties": {
        "type": "RestService",
        "typeProperties": {
            "authenticationType": "Basic",
            "url" : "<REST endpoint>",
            "userName": "<user name>",
            "password": {
                "type": "SecureString",
                "value": "<password>"
            }
        },
        "connectVia": {
            "referenceName": "<name of Integration Runtime>",
            "type": "IntegrationRuntimeReference"
        }
    }
}

Use AAD service principal authentication

Set the authenticationType property to AadServicePrincipal. In addition to the generic properties that are described in the preceding section, specify the following properties:

Property Description Required
servicePrincipalId Specify the Azure Active Directory application's client ID. Yes
servicePrincipalKey Specify the Azure Active Directory application's key. Mark this field as a SecureString to store it securely in Data Factory, or reference a secret stored in Azure Key Vault. Yes
tenant Specify the tenant information (domain name or tenant ID) under which your application resides. Retrieve it by hovering the mouse in the top-right corner of the Azure portal. Yes
aadResourceId Specify the AAD resource you are requesting for authorization, for example, https://management.core.windows.net. Yes
azureCloudType For service principal authentication, specify the type of Azure cloud environment to which your AAD application is registered.
Allowed values are AzurePublic, AzureChina, AzureUsGovernment, and AzureGermany. By default, the data factory's cloud environment is used.		 No

Example

{
    "name": "RESTLinkedService",
    "properties": {
        "type": "RestService",
        "typeProperties": {
            "url": "<REST endpoint e.g. https://www.example.com/>",
            "authenticationType": "AadServicePrincipal",
            "servicePrincipalId": "<service principal id>",
            "servicePrincipalKey": {
                "value": "<service principal key>",
                "type": "SecureString"
            },
            "tenant": "<tenant info, e.g. microsoft.onmicrosoft.com>",
            "aadResourceId": "<AAD resource URL e.g. https://management.core.windows.net>"
        },
        "connectVia": {
            "referenceName": "<name of Integration Runtime>",
            "type": "IntegrationRuntimeReference"
        }
    }
}

Use user-assigned managed identity authentication

Set the authenticationType property to ManagedServiceIdentity. In addition to the generic properties that are described in the preceding section, specify the following properties:

Property Description Required
aadResourceId Specify the AAD resource you are requesting for authorization, for example, https://management.core.windows.net. Yes
credentials Specify the user-assigned managed identity as the credential object. Yes

Example

{
    "name": "RESTLinkedService",
    "properties": {
        "type": "RestService",
        "typeProperties": {
            "url": "<REST endpoint e.g. https://www.example.com/>",
            "authenticationType": "ManagedServiceIdentity",
            "aadResourceId": "<AAD resource URL e.g. https://management.core.windows.net>",
            "credential": {
                "referenceName": "credential1",
                "type": "CredentialReference"
            }    
        },
        "connectVia": {
            "referenceName": "<name of Integration Runtime>",
            "type": "IntegrationRuntimeReference"
        }
    }
}

Using authentication headers

In addition, you can configure request headers for authentication along with the built-in authentication types.

Example: Using API key authentication

{
    "name": "RESTLinkedService",
    "properties": {
        "type": "RestService",
        "typeProperties": {
            "url": "<REST endpoint>",
            "authenticationType": "Anonymous",
            "authHeader": {
                "x-api-key": {
                    "type": "SecureString",
                    "value": "<API key>"
                }
            }
        },
        "connectVia": {
            "referenceName": "<name of Integration Runtime>",
            "type": "IntegrationRuntimeReference"
        }
    }
}

Dataset properties

This section provides a list of properties that the REST dataset supports.

For a full list of sections and properties that are available for defining datasets, see Datasets and linked services.

To copy data from REST, the following properties are supported:

Property Description Required
type The type property of the dataset must be set to RestResource. Yes
relativeUrl A relative URL to the resource that contains the data. When this property isn't specified, only the URL that's specified in the linked service definition is used. The HTTP connector copies data from the combined URL: [URL specified in linked service]/[relative URL specified in dataset]. No

If you were setting requestMethod, additionalHeaders, requestBody and paginationRules in dataset, it is still supported as-is, while you are suggested to use the new model in activity going forward.

Example:

{
    "name": "RESTDataset",
    "properties": {
        "type": "RestResource",
        "typeProperties": {
            "relativeUrl": "<relative url>"
        },
        "schema": [],
        "linkedServiceName": {
            "referenceName": "<REST linked service name>",
            "type": "LinkedServiceReference"
        }
    }
}

Copy Activity properties

This section provides a list of properties supported by the REST source and sink.

For a full list of sections and properties that are available for defining activities, see Pipelines.

REST as source

The following properties are supported in the copy activity source section:

Property Description Required
type The type property of the copy activity source must be set to RestSource. Yes
requestMethod The HTTP method. Allowed values are GET (default) and POST. No
additionalHeaders Additional HTTP request headers. No
requestBody The body for the HTTP request. No
paginationRules The pagination rules to compose next page requests. Refer to pagination support section on details. No
httpRequestTimeout The timeout (the TimeSpan value) for the HTTP request to get a response. This value is the timeout to get a response, not the timeout to read response data. The default value is 00:01:40. No
requestInterval The time to wait before sending the request for next page. The default value is 00:00:01 No

Note

REST connector ignores any "Accept" header specified in additionalHeaders. As REST connector only support response in JSON, it will auto generate a header of Accept: application/json.

Example 1: Using the Get method with pagination

"activities":[
    {
        "name": "CopyFromREST",
        "type": "Copy",
        "inputs": [
            {
                "referenceName": "<REST input dataset name>",
                "type": "DatasetReference"
            }
        ],
        "outputs": [
            {
                "referenceName": "<output dataset name>",
                "type": "DatasetReference"
            }
        ],
        "typeProperties": {
            "source": {
                "type": "RestSource",
                "additionalHeaders": {
                    "x-user-defined": "helloworld"
                },
                "paginationRules": {
                    "AbsoluteUrl": "$.paging.next"
                },
                "httpRequestTimeout": "00:01:00"
            },
            "sink": {
                "type": "<sink type>"
            }
        }
    }
]

Example 2: Using the Post method

"activities":[
    {
        "name": "CopyFromREST",
        "type": "Copy",
        "inputs": [
            {
                "referenceName": "<REST input dataset name>",
                "type": "DatasetReference"
            }
        ],
        "outputs": [
            {
                "referenceName": "<output dataset name>",
                "type": "DatasetReference"
            }
        ],
        "typeProperties": {
            "source": {
                "type": "RestSource",
                "requestMethod": "Post",
                "requestBody": "<body for POST REST request>",
                "httpRequestTimeout": "00:01:00"
            },
            "sink": {
                "type": "<sink type>"
            }
        }
    }
]

REST as sink

The following properties are supported in the copy activity sink section:

Property Description Required
type The type property of the copy activity sink must be set to RestSink. Yes
requestMethod The HTTP method. Allowed values are POST (default), PUT, and PATCH. No
additionalHeaders Additional HTTP request headers. No
httpRequestTimeout The timeout (the TimeSpan value) for the HTTP request to get a response. This value is the timeout to get a response, not the timeout to write the data. The default value is 00:01:40. No
requestInterval The interval time between different requests in millisecond. Request interval value should be a number between [10, 60000]. No
httpCompressionType HTTP compression type to use while sending data with Optimal Compression Level. Allowed values are none and gzip. No
writeBatchSize Number of records to write to the REST sink per batch. The default value is 10000. No

REST connector as sink works with the REST APIs that accept JSON. The data will be sent in JSON with the following pattern. As needed, you can use the copy activity schema mapping to reshape the source data to conform to the expected payload by the REST API.

[
    { <data object> },
    { <data object> },
    ...
]

Example:

"activities":[
    {
        "name": "CopyToREST",
        "type": "Copy",
        "inputs": [
            {
                "referenceName": "<input dataset name>",
                "type": "DatasetReference"
            }
        ],
        "outputs": [
            {
                "referenceName": "<REST output dataset name>",
                "type": "DatasetReference"
            }
        ],
        "typeProperties": {
            "source": {
                "type": "<source type>"
            },
            "sink": {
                "type": "RestSink",
                "requestMethod": "POST",
                "httpRequestTimeout": "00:01:40",
                "requestInterval": 10,
                "writeBatchSize": 10000,
                "httpCompressionType": "none",
            },
        }
    }
]

Mapping data flow properties

REST is supported in data flows for both integration datasets and inline datasets.

Source transformation

Property Description Required
requestMethod The HTTP method. Allowed values are GET and POST. Yes
relativeUrl A relative URL to the resource that contains the data. When this property isn't specified, only the URL that's specified in the linked service definition is used. The HTTP connector copies data from the combined URL: [URL specified in linked service]/[relative URL specified in dataset]. No
additionalHeaders Additional HTTP request headers. No
httpRequestTimeout The timeout (the TimeSpan value) for the HTTP request to get a response. This value is the timeout to get a response, not the timeout to write the data. The default value is 00:01:40. No
requestInterval The interval time between different requests in millisecond. Request interval value should be a number between [10, 60000]. No
QueryParameters.request_query_parameter OR QueryParameters['request_query_parameter'] "request_query_parameter" is user-defined, which references one query parameter name in the next HTTP request URL. No

Sink transformation

Property Description Required
additionalHeaders Additional HTTP request headers. No
httpRequestTimeout The timeout (the TimeSpan value) for the HTTP request to get a response. This value is the timeout to get a response, not the timeout to write the data. The default value is 00:01:40. No
requestInterval The interval time between different requests in millisecond. Request interval value should be a number between [10, 60000]. No
httpCompressionType HTTP compression type to use while sending data with Optimal Compression Level. Allowed values are none and gzip. No
writeBatchSize Number of records to write to the REST sink per batch. The default value is 10000. No

You can set the delete, insert, update, and upsert methods as well as the relative row data to send to the REST sink for CRUD operations.

:::image type="content" source="media/data-flow/data-flow-sink.png" alt-text="Data flow REST sink":::

Sample data flow script

Notice the use of an alter row transformation prior to the sink to instruct ADF what type of action to take with your REST sink. I.e. insert, update, upsert, delete.

AlterRow1 sink(allowSchemaDrift: true,
	validateSchema: false,
	deletable:true,
	insertable:true,
	updateable:true,
	upsertable:true,
	rowRelativeUrl: 'periods',
	insertHttpMethod: 'PUT',
	deleteHttpMethod: 'DELETE',
	upsertHttpMethod: 'PUT',
	updateHttpMethod: 'PATCH',
	timeout: 30,
	requestFormat: ['type' -> 'json'],
	skipDuplicateMapInputs: true,
	skipDuplicateMapOutputs: true) ~> sink1

Pagination support

When copying data from REST APIs, normally, the REST API limits its response payload size of a single request under a reasonable number; while to return large amount of data, it splits the result into multiple pages and requires callers to send consecutive requests to get next page of the result. Usually, the request for one page is dynamic and composed by the information returned from the response of previous page.

This generic REST connector supports the following pagination patterns:

  • Next request’s absolute or relative URL = property value in current response body
  • Next request’s absolute or relative URL = header value in current response headers
  • Next request’s query parameter = property value in current response body
  • Next request’s query parameter = header value in current response headers
  • Next request’s header = property value in current response body
  • Next request’s header = header value in current response headers

Pagination rules are defined as a dictionary in dataset, which contains one or more case-sensitive key-value pairs. The configuration will be used to generate the request starting from the second page. The connector will stop iterating when it gets HTTP status code 204 (No Content), or any of the JSONPath expressions in "paginationRules" returns null.

Supported keys in pagination rules:

Key Description
AbsoluteUrl Indicates the URL to issue the next request. It can be either absolute URL or relative URL.
QueryParameters.request_query_parameter OR QueryParameters['request_query_parameter'] "request_query_parameter" is user-defined, which references one query parameter name in the next HTTP request URL.
Headers.request_header OR Headers['request_header'] "request_header" is user-defined, which references one header name in the next HTTP request.
EndCondition:end_condition "end_condition" is user-defined, which indicates the condition that will end the pagination loop in the next HTTP request.
MaxRequestNumber Indicates the maximum pagination request number. Leave it as empty means no limit.
SupportRFC5988 By default, this is set to true if no pagination rule is defined. You can disable this rule by setting supportRFC5988 to false or remove this property from script.

Supported values in pagination rules:

Value Description
Headers.response_header OR Headers['response_header'] "response_header" is user-defined, which references one header name in the current HTTP response, the value of which will be used to issue next request.
A JSONPath expression starting with "$" (representing the root of the response body) The response body should contain only one JSON object. The JSONPath expression should return a single primitive value, which will be used to issue next request.

Note

The pagination rules in mapping data flows is different from it in copy activity in the following aspects:

  1. Range is not supported in mapping data flows.
  2. [''] is not supported in mapping data flows. Instead, use {} to escape special character. For example, body.{@odata.nextLink}, whose JSON node @odata.nextLink contains special character . .
  3. The end condition is supported in mapping data flows, but the condition syntax is different from it in copy activity. body is used to indicate the response body instead of $. header is used to indicate the response header instead of headers. Here are two examples showing this difference:
    • Example 1:
      Copy activity: "EndCondition:$.data": "Empty"
      Mapping data flows: "EndCondition:body.data": "Empty"
    • Example 2:
      Copy activity: "EndCondition:headers.complete": "Exist"
      Mapping data flows: "EndCondition:header.complete": "Exist"

Pagination rules examples

This section provides a list of examples for pagination rules settings.

Example 1: Variables in QueryParameters

This example provides the configuration steps to send multiple requests whose variables are in QueryParameters.

Multiple requests:

baseUrl/api/now/table/incident?sysparm_limit=1000&sysparm_offset=0,
baseUrl/api/now/table/incident?sysparm_limit=1000&sysparm_offset=1000,
...... 
baseUrl/api/now/table/incident?sysparm_limit=1000&sysparm_offset=10000

Step 1: Input sysparm_offset={offset} either in Base URL or Relative URL as shown in the following screenshots:

:::image type="content" source="media/connector-rest/pagination-rule-example-1-rest-linked-service-base-url.png" alt-text="Screenshot showing one configuration to send multiple requests whose variables are in Query Parameters.":::

or

:::image type="content" source="media/connector-rest/pagination-rule-example-1-rest-linked-service-relative-url.png" alt-text="Screenshot showing another configuration to send multiple requests whose variables are in Query Parameters.":::

Step 2: Set Pagination rules as either option 1 or option 2：

  • Option1: "QueryParameters.{offset}" : "RANGE:0:10000:1000"

  • Option2: "AbsoluteUrl.{offset}" : "RANGE:0:10000:1000"

Example 2：Variables in AbsoluteUrl

This example provides the configuration steps to send multiple requests whose variables are in AbsoluteUrl.

Multiple requests:

BaseUrl/api/now/table/t1
BaseUrl/api/now/table/t2
...... 
BaseUrl/api/now/table/t100

Step 1: Input {id} either in Base URL in the linked service configuration page or Relative URL in the dataset connection pane.

:::image type="content" source="media/connector-rest/pagination-rule-example-2-rest-linked-service-base-url.png" alt-text="Screenshot showing one configuration to send multiple requests whose variables are in Absolute Url.":::

or

:::image type="content" source="media/connector-rest/pagination-rule-example-2-rest-linked-service-relative-url.png" alt-text="Screenshot showing another configuration to send multiple requests whose variables are in Absolute Url.":::

Step 2: Set Pagination rules as "AbsoluteUrl.{id}" :"RANGE:1:100:1".

Example 3：Variables in Headers

This example provides the configuration steps to send multiple requests whose variables are in Headers.

Multiple requests:
RequestUrl: https://example/table
Request 1: Header(id->0)
Request 2: Header(id->10)
......
Request 100: Header(id->100)

Step 1: Input {id} in Additional headers.

Step 2: Set Pagination rules as "Headers.{id}" : "RARNGE:0:100:10".

:::image type="content" source="media/connector-rest/pagination-rule-example-3.png" alt-text="Screenshot showing the pagination rule to send multiple requests whose variables are in Headers.":::

Example 4：Variables are in AbsoluteUrl/QueryParameters/Headers, the end variable is not pre-defined and the end condition is based on the response

This example provides configuration steps to send multiple requests whose variables are in AbsoluteUrl/QueryParameters/Headers but the end variable is not defined. For different responses, different end condition rule settings are shown in Example 4.1-4.6.

Multiple requests:

Request 1: baseUrl/api/now/table/incident?sysparm_limit=1000&sysparm_offset=0, 
Request 2: baseUrl/api/now/table/incident?sysparm_limit=1000&sysparm_offset=1000,
Request 3: baseUrl/api/now/table/incident?sysparm_limit=1000&sysparm_offset=2000,
......

Two responses encountered in this example:

Response 1：

{
    Data: [
        {key1: val1, key2: val2
        },
        {key1: val3, key2: val4
        }
    ]
}

Response 2：

{
    Data: [
        {key1: val5, key2: val6
        },
        {key1: val7, key2: val8
        }
    ]
}

Step 1: Set the range of Pagination rules as Example 1 and leave the end of range empty as "AbsoluteUrl.{offset}": "RANGE:0::1000".

Step 2: Set different end condition rules according to different last responses. See below examples:

  • Example 4.1: The pagination ends when the value of the specific node in response is empty

    The REST API returns the last response in the following structure:

    {
    Data: []
}

    Set the end condition rule as "EndCondition:$.data": "Empty" to end the pagination when the value of the specific node in response is empty.

    :::image type="content" source="media/connector-rest/pagination-rule-example-4-1.png" alt-text="Screenshot showing the End Condition setting for Example 4.1.":::

  • Example 4.2: The pagination ends when the value of the specific node in response dose not exist

    The REST API returns the last response in the following structure:

    {}

    Set the end condition rule as "EndCondition:$.data": "NonExist" to end the pagination when the value of the specific node in response dose not exist.

    :::image type="content" source="media/connector-rest/pagination-rule-example-4-2.png" alt-text="Screenshot showing the End Condition setting for Example 4.2.":::

  • Example 4.3: The pagination ends when the value of the specific node in response exists

    The REST API returns the last response in the following structure:

    {
    Data: [
        {key1: val991, key2: val992
        },
        {key1: val993, key2: val994
        }
    ],
            Complete: true
}

    Set the end condition rule as "EndCondition:$.Complete": "Exist" to end the pagination when the value of the specific node in response exists.

    :::image type="content" source="media/connector-rest/pagination-rule-example-4-3.png" alt-text="Screenshot showing the End Condition setting for Example 4.3.":::

  • Example 4.4: The pagination ends when the value of the specific node in response is a user-defined const value

    The REST API returns the response in the following structure:

    {
    Data: [
        {key1: val1, key2: val2
        },
        {key1: val3, key2: val4
        }
    ],
            Complete: false
}

    ......

    And the last response is in the following structure:

    {
    Data: [
        {key1: val991, key2: val992
        },
        {key1: val993, key2: val994
        }
    ],
            Complete: true
}

    Set the end condition rule as "EndCondition:$.Complete": "Const:true" to end the pagination when the value of the specific node in response is a user-defined const value.

    :::image type="content" source="media/connector-rest/pagination-rule-example-4-4.png" alt-text="Screenshot showing the End Condition setting for Example 4.4.":::

  • Example 4.5: The pagination ends when the value of the header key in response equals to user-defined const value

    The header keys in REST API responses are shown in the structure below:

    Response header 1: header(Complete->0)
    ......
    Last Response header: header(Complete->1)

    Set the end condition rule as "EndCondition:headers.Complete": "Const:1" to end the pagination when the value of the header key in response is equal to user-defined const value.

    :::image type="content" source="media/connector-rest/pagination-rule-example-4-5.png" alt-text="Screenshot showing the End Condition setting for Example 4.5.":::

  • Example 4.6: The pagination ends when the key exists in the response header

    The header keys in REST API responses are shown in the structure below:

    Response header 1: header()
    ......
    Last Response header: header(CompleteTime->20220920)

    Set the end condition rule as "EndCondition:headers.CompleteTime": "Exist" to end the pagination when the key exists in the response header.

    :::image type="content" source="media/connector-rest/pagination-rule-example-4-6.png" alt-text="Screenshot showing the End Condition setting for Example 4.6.":::

Example 5：Set end condition to avoid endless requests when range rule is not defined

This example provides the configuration steps to send multiple requests when the range rule is not used. The end condition can be set refer to Example 4.1-4.6 to avoid endless requests. The REST API returns response in the following structure, in which case next page's URL is represented in paging.next.

{
    "data": [
        {
            "created_time": "2017-12-12T14:12:20+0000",
            "name": "album1",
            "id": "1809938745705498_1809939942372045"
        },
        {
            "created_time": "2017-12-12T14:14:03+0000",
            "name": "album2",
            "id": "1809938745705498_1809941802371859"
        },
        {
            "created_time": "2017-12-12T14:14:11+0000",
            "name": "album3",
            "id": "1809938745705498_1809941879038518"
        }
    ],
    "paging": {
        "cursors": {
            "after": "MTAxNTExOTQ1MjAwNzI5NDE=",
            "before": "NDMyNzQyODI3OTQw"
        },
        "previous": "https://graph.facebook.com/me/albums?limit=25&before=NDMyNzQyODI3OTQw",
        "next": "https://graph.facebook.com/me/albums?limit=25&after=MTAxNTExOTQ1MjAwNzI5NDE="
    }
}
...

The last response is:

{
    "data": [],
    "paging": {
        "cursors": {
            "after": "MTAxNTExOTQ1MjAwNzI5NDE=",
            "before": "NDMyNzQyODI3OTQw"
        },
        "previous": "https://graph.facebook.com/me/albums?limit=25&before=NDMyNzQyODI3OTQw",
        "next": "Same with Last Request URL"
    }
}

Step 1: Set Pagination rules as "AbsoluteUrl": "$.paging.next".

Step 2: If next in the last response is always same with the last request URL and not empty, endless requests will be sent. The end condition can be used to avoid endless requests. Therefore, set the end condition rule refer to Example 4.1-4.6.

Example 6：Set the max request number to avoid endless request

Set MaxRequestNumber to avoid endless request as shown in the following screenshot:

:::image type="content" source="media/connector-rest/pagination-rule-example-6.png" alt-text="Screenshot showing the Max Request Number setting for Example 6.":::

Example 7：The RFC 5988 pagination rule is supported by default

The backend will automatically get the next URL based on the RFC 5988 style links in the header.

:::image type="content" source="media/connector-rest/pagination-rule-example-7-http-header.png" alt-text="Screenshot showing samples of the http header that complies with R F C 5988.":::

Tip

If you don't want to enable this default pagination rule, you can set supportRFC5988 to false or just delete it in the script.

:::image type="content" source="media/connector-rest/pagination-rule-example-7-disable-rfc5988.png" alt-text="Screenshot showing how to disable R F C 5988 setting for Example 7.":::

Example 8: The next request URL is from the response body when use pagination in mapping data flows

This example states how to set the pagination rule and the end condition rule in mapping data flows when the next request URL is from the response body.

The response schema is shown below:

:::image type="content" source="media/connector-rest/pagination-rule-example-8-response-schema.png" alt-text="Screenshot showing the response schema of Example 8.":::

The pagination rules should be set as the following screenshot:

:::image type="content" source="media/connector-rest/pagination-rule-example-8.png" alt-text="Screenshot showing how to set the pagination rule for Example 8.":::

By default, the pagination will stop when body .{@odata.nextLink} is null or empty.

But if the value of @odata.nextLink in the last response body is equal to the last request URL, then it will lead to the endless loop. To avoid this condition, define end condition rules.

  • If Value in the last response is Empty, then the end condition rule can be set as below:

    :::image type="content" source="media/connector-rest/pagination-rule-example-8-end-condition-1.png" alt-text="Screenshot showing setting the end condition rule when the last response is empty.":::

  • If the value of the complete key in the response header equals to true indicates the end of pagination, then the end condition rule can be set as below:

    :::image type="content" source="media/connector-rest/pagination-rule-example-8-end-condition-2.png" alt-text="Screenshot showing setting the end condition rule when the complete key in the response header equals to true indicates the end of pagination.":::

Example 9: The response format is XML and the next request URL is from the response body when use pagination in mapping data flows

This example states how to set the pagination rule in mapping data flows when the response format is XML and the next request URL is from the response body. As shown in the following screenshot, the first URL is https://<user>.dfs.core.windows.net/bugfix/test/movie_1.xml

:::image type="content" source="media/connector-rest/pagination-rule-example-9-situation.png" alt-text="Screenshot showing the response format is X M L and the next request U R L is from the response body.":::

The response schema is shown below:

:::image type="content" source="media/connector-rest/pagination-rule-example-9-response-schema.png" alt-text="Screenshot showing the response schema of Example 9.":::

The pagination rule syntax is the same as in Example 8 and should be set as below in this example:

:::image type="content" source="media/connector-rest/pagination-rule-example-9.png" alt-text="Screenshot showing setting the pagination rule for Example 9.":::

Use OAuth

This section describes how to use a solution template to copy data from REST connector into Azure Data Lake Storage in JSON format using OAuth.

About the solution template

The template contains two activities:

  • Web activity retrieves the bearer token and then pass it to subsequent Copy activity as authorization.
  • Copy activity copies data from REST to Azure Data Lake Storage.

The template defines two parameters:

  • SinkContainer is the root folder path where the data is copied to in your Azure Data Lake Storage.
  • SinkDirectory is the directory path under the root where the data is copied to in your Azure Data Lake Storage.

How to use this solution template

  1. Go to the Copy from REST or HTTP using OAuth template. Create a new connection for Source Connection. :::image type="content" source="media/solution-template-copy-from-rest-or-http-using-oauth/source-connection.png" alt-text="Create new connections":::

    Below are key steps for new linked service (REST) settings:

    1. Under Base URL, specify the url parameter for your own source REST service.
    2. For Authentication type, choose Anonymous. :::image type="content" source="media/solution-template-copy-from-rest-or-http-using-oauth/new-rest-connection.png" alt-text="New REST connection":::

  2. Create a new connection for Destination Connection.
    :::image type="content" source="media/solution-template-copy-from-rest-or-http-using-oauth/destination-connection.png" alt-text="New Gen2 connection":::

  3. Select Use this template. :::image type="content" source="media/solution-template-copy-from-rest-or-http-using-oauth/use-this-template.png" alt-text="Use this template":::

  4. You would see the pipeline created as shown in the following example: :::image type="content" source="media/solution-template-copy-from-rest-or-http-using-oauth/pipeline.png" alt-text="Screenshot shows the pipeline created from the template.":::

  5. Select Web activity. In Settings, specify the corresponding URL, Method, Headers, and Body to retrieve OAuth bearer token from the login API of the service that you want to copy data from. The placeholder in the template showcases a sample of Azure Active Directory (AAD) OAuth. Note AAD authentication is natively supported by REST connector, here is just an example for OAuth flow.

    Property Description
    URL Specify the url to retrieve OAuth bearer token from. for example, in the sample here it's https://login.microsoftonline.com/microsoft.onmicrosoft.com/oauth2/token
    Method The HTTP method. Allowed values are Post and Get.
    Headers Header is user-defined, which references one header name in the HTTP request.
    Body The body for the HTTP request.

    :::image type="content" source="media/solution-template-copy-from-rest-or-http-using-oauth/web-settings.png" alt-text="Pipeline":::

  6. In Copy data activity, select Source tab, you could see that the bearer token (access_token) retrieved from previous step would be passed to Copy data activity as Authorization under Additional headers. Confirm settings for following properties before starting a pipeline run.

    Property Description
    Request method The HTTP method. Allowed values are Get (default) and Post.
    Additional headers Additional HTTP request headers.

    :::image type="content" source="media/solution-template-copy-from-rest-or-http-using-oauth/copy-data-settings.png" alt-text="Copy source Authentication":::

  7. Select Debug, enter the Parameters, and then select Finish. :::image type="content" source="media/solution-template-copy-from-rest-or-http-using-oauth/pipeline-run.png" alt-text="Pipeline run":::

  8. When the pipeline run completes successfully, you would see the result similar to the following example: :::image type="content" source="media/solution-template-copy-from-rest-or-http-using-oauth/run-result.png" alt-text="Pipeline run result":::

  9. Click the "Output" icon of WebActivity in Actions column, you would see the access_token returned by the service.

    :::image type="content" source="media/solution-template-copy-from-rest-or-http-using-oauth/token-output.png" alt-text="Token output":::

  10. Click the "Input" icon of CopyActivity in Actions column, you would see the access_token retrieved by WebActivity is passed to CopyActivity for authentication.

    :::image type="content" source="media/solution-template-copy-from-rest-or-http-using-oauth/token-input.png" alt-text="Token input":::

    [!CAUTION] To avoid token being logged in plain text, enable "Secure output" in Web activity and "Secure input" in Copy activity.

Export JSON response as-is

You can use this REST connector to export REST API JSON response as-is to various file-based stores. To achieve such schema-agnostic copy, skip the "structure" (also called schema) section in dataset and schema mapping in copy activity.

Schema mapping

To copy data from REST endpoint to tabular sink, refer to schema mapping.

Next steps

For a list of data stores that Copy Activity supports as sources and sinks in Azure Data Factory, see Supported data stores and formats.