If the string length for fields in a JSON payload exceeds 20 MB, a REST Adapter trigger connection fails with the following error:

ORABPEL-15235 Translation Failure. Failed to translate JSON to XML. String length (20038094)
exceeds the maximum length (20000000) The incoming data does not conform to the NXSD schema. 
Please correct the problem

A REST Adapter connection attempting to invoke an external REST service retries three times approximately every 30 seconds upon receiving a 504 gateway timeout error. This behavior is by design and cannot be changed.

Learn about troubleshooting configuration issues when using the Resource Principal Session Token (RPST) and the OCI Service Invocation security policy.

[CDATA[{\"code\":\"NamespaceNotFound\",\"message\":\"You do not have authorization to perform this request, 
or the requested resource could not be found.\"}.The HTTP 404, 404 Not Found, and 404 error message is a Hypertext 
Transfer Protocol (HTTP) standard response code, in computer network communications, to indicate that the client 
was able to communicate with a given server, but the server could not find the resource that was requested. Carefully 
re-examine the target endpoint that is being called. ]]>

[CDATA[{"code":"BucketAlreadyExists","message":"Either the bucket 'test-rpst-OICServiceInstance-phx-NoPermission' 
in namespace 'axkbv4jfb37h' already exists or you are not authorized to create it"}.This error usually indicates that the 
request submitted by Oracle Integration Cloud can not be completed because it conflicts with some rule already established 
by the service. This is usually a functional error. If the call to the target service using a cURL request is successful 
then contact oracle support with the details.

allow dynamic-group rpst_oic-prod-phx-123_Dynamic_Group to read buckets in compartment oic-dev:pp-phx-123-comp

<![CDATA[{\"code\":\"NamespaceNotFound\",\"message\":\"You do not have authorization to perform this request, or 
the requested resource could not be found.\"}.The HTTP 404, 404 Not Found, and 404 error message is a Hypertext Transfer 
Protocol (HTTP) standard response code, in computer network communications, to indicate that the client was able to communicate
 with a given server, but the server could not find the resource that was requested. Carefully re-examine the target endpoint 
that is being called. ]]>

instance.id = service_instance_ocid

resource.id = 'client_ID'

<![CDATA[{\"code\":\"NamespaceNotFound\",\"message\":\"You do not 
have authorization to perform this request, or the requested resource could
not be found.\"}.The HTTP 404, 404 Not Found, and 404 error message is a 
Hypertext Transfer Protocol (HTTP) standard response code, in computer 
network communications, to indicate that the client was able to communicate 
with a given server, but the server could not find the resource that was 
requested. Carefully re-examine the target endpoint that is being called. ]]>

resource.id = service_instance_OCID

resource.id = 'client_ID'

Ensure that the attachment properties - attachment content type is mapped with an appropriate value. The sample documentation for request mapping provides information.

See Map to Construct the Payload for an External REST API that Accepts multipart/form-data as the Content Type.

Private keys downloaded from the Oracle Cloud Infrastructure Console are in PKCS8 format. The OCI Signature Version 1 security policy available with the REST Adapter only supports reading of the private key in RSA format (PKCS1 format).

CASDK-0005: A connector specific exception was raised by the application.
java.lang.ClassCastException: org.bouncycastle.asn1.pkcs.PrivateKeyInfo
cannot be cast to org.bouncycastle.openssl.PEMKeyPair;
org.bouncycastle.asn1.pkcs.PrivateKeyInfo cannot be cast to
org.bouncycastle.openssl.PEMKeyPair

The HTTP error response returned by integrations created prior to release 20.4.2 (November 2020 quarterly release) that include a REST Adapter-based trigger connection does not strictly conform to the OpenAPI specification.

{
  "type" :
"http://www.w3.org/Protocols/rfc2616/rfc2616-sec10.html#sec10.5.1",
  "title" : "Internal Server Error",
  "detail" : "An internal error occurred while processing the request. Please
see the fault details for the nested error details.",
  "o:errorCode" : "400",
  "o:errorDetails" : [ {
    "type" :
"http://www.w3.org/Protocols/rfc2616/rfc2616-sec10.html#sec10.4.5",
    "instance" : "<![CDATA[{}.The HTTP 404, 404 Not Found, and 404 error
message
is a Hypertext Transfer Protocol (HTTP) standard response code, in computer
network communications, to indicate that the client was able to communicate
with a given server, but the server could not find the resource that was
requested.
Carefully re-examine the target endpoint that is being called. ]]>",
    "title" : "Not Found",
    "o:errorPath" : "<![CDATA[GET http://api.zippopotam.us/us/9021011
returned a response status of 404 Not Found]]>",
    "o:errorCode" : "404"
  } ]
}

With the November 2020 release (20.4.2), the HTTP error response format has been modified for newly created integrations to be compliant with the OpenAPI specification. The o: previously prefixed to certain keys has been removed, as shown in the following message.

However, note that all existing, pre-20.4.2 integrations continue to have the same error response shown above, even when those integrations are modified.

{
  "type" :
"http://www.w3.org/Protocols/rfc2616/rfc2616-sec10.html#sec10.5.1",
  "title" : "Internal Server Error",
  "detail" : "An internal error occurred while processing the request. Please
see the fault details for the nested error details.",
  "errorCode" : "404",
  "errorDetails" : [ {
    "type" :
"http://www.w3.org/Protocols/rfc2616/rfc2616-sec10.html#sec10.4.5",
    "instance" : "<![CDATA[{}.The HTTP 404, 404 Not Found, and 404 error
message
is a Hypertext Transfer Protocol (HTTP) standard response code, in computer
network communications, to indicate that the client was able to communicate
with a given server, but the server could not find the resource that was
requested.
Carefully re-examine the target endpoint that is being called. ]]>",
    "title" : "Not Found",
    "errorPath" : "<![CDATA[GET http://api.zippopotam.us/us/9021011 returned a
response status of 404 Not Found]]>",
    "errorCode" : "404"
  } ]
}

The REST Adapter can be configured for only a single type of response. A service that returns multiple responses, even with different HTTP success status codes, is not supported. All except for the configured response type result in an APIInvocationError. You can catch the resulting error using a scope action and a fault handler if the fault is not required in the integration.

The REST Adapter uses the following strategy to handle errors in the invoke (outbound) and trigger (inbound) directions.

Error Handling in the Trigger (Inbound) Direction

The REST Adapter in the trigger (inbound) direction exposes an HTTP endpoint that HTTP clients can request for using an HTTP request, and returns an HTTP response.

If successful, the REST Adapter returns a success response. The REST Adapter returns an error response with an HTTP status belonging to the error family of codes depending on the situation. The following table describes the possible cause and the REST Adapter response.

Condition	HTTP Status	Details
Invalid client request	4xx	There are several conditions that can cause client side failures, including: An invalid resource URL Incorrect query parameters An unsupported method type An unsupported media type Bad data
Downstream processing errors	5xx	All other errors that can occur within the integration, including: An invalid target An HTTP error response General processing errors

In addition, the REST Adapter also returns an error response with additional details about the error and possible steps for troubleshooting. The standard error response format is returned according to the configured response media type. The following is a sample JSON response structure:

{
  "type" : "http://www.w3.org/Protocols/rfc2616/rfc2616-sec10.html#sec10.5.1",
  "title" : "Internal Server Error",
  "detail" : "An internal error occurred while processing the request. Please see the fault details for the nested error details.",
  "o:errorCode" : "500",
  "o:errorDetails" : [ {
    "type" : "http://www.w3.org/Protocols/rfc2616/rfc2616-sec10.html#sec10.4.1",
    "instance" : "{\n   \"error_message\" : \"Invalid request. Missing the 'origin' parameter.\",\n   \"routes\" : [],\n   
    \"status\" : \"INVALID_REQUEST\"\n}\n",
    "title" : "Bad Request",
    "o:errorPath" : "GET http://maps.googleapis.com/maps/api/directions/json?destination=Montreal returned a response status of 
      400 Bad Request",
    "o:errorCode" : "APIInvocationError"
  } ]
}

The o:errorDetails section is reserved for the actual cause. The prefix o: included is based on Oracle standards.

The top portion is used to add any integration-specific details to the fault. This is typically not necessary, but if you want to control the HTTP status, title, and details, set these values appropriately. If not entered, sufficient default values are provided by the REST Adapter.

Note:

The REST Adapter returns the downstream errors with a 500 Internal server error code. You can override these errors and provide a custom error code by assigning an appropriate value to APIInvocationError/errorCode in the target mapper.

The suggested mappings to map faults raised by an outbound system to the trigger (inbound) REST Adapter are as follows:

Description of the illustration error_mapper.png

The top section is left out in this mapping and these are appropriately assigned by the REST Adapter in the previously described sample.

Unmapped faults are propagated as system faults by Oracle Integration to the inbound REST Adapter. They may not communicate the appropriate details. Therefore, it is recommended that you define the fault pipelines.

If a REST service invoked using the REST Adapter consistently returns a response status of 401 Unauthorized, it may be because the application credentials configured on the Connections page are no longer valid.

The Connections page does not validate the credentials. Even if the test connection is successful, it may not be sufficient because the test connection only validates the parameters defined on the Connections page.

Because the parameters defined on the Connections page are used to call the target endpoint REST API, which is configured as part of endpoint configuration, it is strongly recommended that you test the endpoint configuration that uses this connection.

Note the following issue with the REST Adapter multiple resources per endpoint use case in the Adapter Endpoint Configuration Wizard.

The REST Adapter removes keys with null values during JSON transformation.

{
"input" : "input",
"val" :  null,
"response": "response"
} 

{
"input" : "input",
"response": "response"
}

{
"input" : "input",
"val" :  "",
"response": "response"
}

The sample JSON file is typically large when it has repeating structures. You can purge such repetitions because the sample only needs to represent the structure and not the instance document. However, if the JSON file is unusually large and cannot be trimmed, perform the following the steps:

1. Replace all occurrences of special characters (for example, $) with their corresponding codes in the sample JSON file. See JSON to XML Special Character Conversion.
2. Use the modified JSON file to complete the configuration.
3. Select the generated schema in the Adapter Endpoint Configuration Wizard.

For SSL certificate errors, perform the following tasks.

You can define REST Adapter fault and response pipelines in Basic Routing integrations.

The REST Adapter on the trigger (inbound) side exposes an HTTP endpoint that HTTP clients can request for using an HTTP request, and returns an HTTP response.

If successful, the REST Adapter returns a success response. The REST Adapter returns an error response with an HTTP status belonging to the error family of codes depending on the situation. This table describes the possible cause and the REST Adapter response.

In addition, the REST Adapter also returns an error response with additional details about the error and possible steps for troubleshooting. The standard error response format is returned according to the configured response media type. The following is a sample JSON response structure:

{
  "type" : "http://www.w3.org/Protocols/rfc2616/rfc2616-sec10.html#sec10.5.1",
  "title" : "Internal Server Error",
  "detail" : "An internal error occurred while processing the request. Please see the fault details for the nested error details.",
  "o:errorCode" : "500",
  "o:errorDetails" : [ {
    "type" : "http://www.w3.org/Protocols/rfc2616/rfc2616-sec10.html#sec10.4.1",
    "instance" : "{\n   \"error_message\" : \"Invalid request. Missing the 'origin' parameter.\",\n   \"routes\" : [],\n   
    \"status\" : \"INVALID_REQUEST\"\n}\n",
    "title" : "Bad Request",
    "o:errorPath" : "GET http://maps.googleapis.com/maps/api/directions/json?destination=Montreal returned a response status of 
      400 Bad Request",
    "o:errorCode" : "APIInvocationError"
  } ]
}

The errorDetails section is reserved for the actual cause. You must configure the fault pipelines to map the target faults into this element. The top portion is used to add any integration-specific details to the fault. This is typically not necessary, but if you want to control the HTTP status, title, and details, then set these values appropriately. If not entered, sufficient default values are provided by the adapter.

The suggested mappings to map faults raised by an outbound system to the trigger (inbound) REST Adapter are as follows:

The top section is left out in this mapping and so these are appropriately assigned by the adapter in the previously described sample.

Unmapped faults are propagated as system faults by Oracle Integration to the inbound adapter. They may not communicate the appropriate details. Therefore, it is recommended that you define the fault pipelines.

When configuring the REST Adapter, if a JSON property in the included JSON sample file has an empty array, you receive the following error message. Note the last part of the message. Modify the JSON sample file to include a value for the JSON property.

Description of the illustration ics_rest_json_empty_ary.png

While designing the REST Adapter in the Adapter Endpoint Configuration Wizard, carefully review the contents on the Summary page. The endpoint URI must match the invoke service URI. If you do not see the necessary values, review your invoke connection and the outbound service. The base URI in the connection and resource URI in the invoke service must add up to the endpoint URI.

You can receive the following error in the icsServer-diagnostic.log file when invoking JD Edwards Form Service from an integration in which a REST Adapter is configured as the invoke connection.

[2016-06-07T02:13:54.346-07:00] [icsServer] [ERROR] [] 
[oracle.osb.transports.jca] [tid: [ACTIVE].ExecuteThread: '14' 
for queue: 'weblogic.kernel.Default (self-tuning)'] [userId: <anonymous>] 
[ecid: f23c428c-9247-459c-bb9f-22cbadbeda35-0003651d,0] [APP: Service Bus JCA 
Transport Provider] [oracle.soa.tracking.FlowId: 59] [FlowId: 
0000LKe8vtD7MAW5Hzw0yf1NGeIK00001c] Error sending bytes to socket: 
<genericRestFault><errorCode>500</errorCode><errorPath><![CDATA[POST 
http://den60208jems.my_domain.com:9516/jderest/formservice returned a 
response status of 500 Internal Server Error]]></errorPath><instance><![CDATA[{[[   
"message" : "Can not deserialize instance of java.util.ArrayList out of 
START_OBJECT token\n at [Source: java.io.StringReader@68f2c85d; line: 1, column: 
218] (through reference chain: 
com.oracle.e1.jdemf.FormRequest[\"formInputs\"])",   "exception" : "com.fasterxml.jackson.databind.JsonMappingException",   
"timeStamp" : "2016-06-07:03.13.54" }]]></instance></genericRestFault> 
]]

"formInputs": [ "input1" ]

"formInputs": [ "input1", "input2" ]

When configuring the REST Adapter in the Adapter Endpoint Configuration Wizard, you must click Next to save your changes and move to the next page of the wizard. For example, if you configure details on the Request page, click the tab of the Basic Info page in the left pane, then click Next to return to the Request page, none of your previous configurations were saved, and the page is empty.

You can convert XML to a JSON document. Oracle Integration resolves an XML element with a number value to XML schema with a type of number, which converts the XML to a JSON document with a type of number.

The workaround is to use a string value for the phone number in the sample XML. The XML schema generated has a type of string. At runtime, the XML to JSON conversion produces the desired JSON. For example:

• XML:

  <Phone>a23249480</Phone> <!-- modified -->

• Generated XSD:

  <element name="phone" type="string"/>

At runtime:

• XML

  <Phone>23249480</Phone>

• JSON

  "Phone": "23249480"

The following special characters are supported in JSON samples.

• " " (blank space)

• /

• \\

• ;

• (

• )

• &

• ,

• #

• ?

• <

• >

The content-type is missing for an asynchronous flow.

The upper limit of characters that work in REST URLs in integrations with the REST Adapter is 8251. If you exceed this limit, a 414 Request-URI Too Large error occurs.

If you want to send a "null" value instead of "" for any specific key in JSON through the REST Adapter, you must map "xsi:nil=true" through the mapper for that specific key.