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503 Service Unavailable For RESTFul Services Using {param} (Doc ID 2506391.1)

Last updated on OCTOBER 22, 2019

Applies to:

Oracle REST Data Services - Version 3.0.12 to 18.4
Oracle Cloud Infrastructure - Database Service - Version N/A and later
Information in this document applies to any platform.


Using ORDS 18.X

When attempting to consume a RESTFul with the format as


the following error occurs.

503 Service Unavailable

and in ORDS logs you may see:

<[ServletContext@14239301[.....]] Servlet failed with an Exception
oracle.dbtools.common.util.URIs$IllegalURIException: The URI is not well-formed, reason: Malformed escape pair at position: 56
  at oracle.dbtools.common.util.URIs.illegalUri(
  at oracle.dbtools.common.util.URIs.create(
  at oracle.dbtools.common.util.URIs.uri(
  at oracle.dbtools.http.servlet.UriRequest.builder(
  at oracle.dbtools.http.servlet.UriRequest.uriRequest(
  Truncated. see log file for complete stacktrace
Caused By: Malformed escape pair at index 56: http://<HOST>/ords/alias/template/rest_names/{%parameter}%
  Truncated. see log file for complete stacktrace

The issue can be reproduced at will with the following steps:
1. Upgrade ORDS from 2.0.10 to 18.4
2. Test the REST Service with parameters using {}
3. Get the 503 error instead of the data expected


 Updated ORDS from 2.X (when it was called the APEX Listener) to 18.X


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