Introduction
Oracle Integration Cloud (OIC) is great at orchestrating APIs, but it has a limitation when dealing with HTTP redirects. Many external services return shortened or deflected URLs that internally redirect multiple times before reaching the final destination URL.
OIC REST Adapter does not reliably expose the final redirected URL in such cases. This becomes a blocker when downstream logic depends on extracting values (like UUIDs, tokens, or IDs) from the final URL.
To solve this, we can use OCI Functions as a lightweight middleware to resolve redirects and return the final URL back to OIC.
Problem Statement (Use Case)
OIC invokes an external API (for example: email body from Microsoft Graph, SendGrid, or any notification service). The response contains a short or redirected URL. OIC needs the final resolved URL to:
Extract a UUID or parameter
Call another API
Perform validation or tracking
OIC REST Adapter does not provide the final redirected URL easily.
Solution Overview
We introduce OCI Functions between OIC and the redirected URL.
High-Level Flow
OIC extracts the redirected/short URL from API response.
OIC calls an OCI Function, passing the URL as input.
OCI Function:
Follows HTTP redirects
Resolves the final destination URL
OCI Function returns the final URL to OIC.
OIC continues processing (UUID extraction, API calls, etc.).
Architecture Diagram (Logical):
OIC → OCI Function → External Redirect URL
↑ ↓
└──── Final URL ──────┘
OCI Function Implementation
You can use Java, Node.js or Python. Below I have used Java code.
package com.clp.fn;
import java.net.URI;
import java.net.URLDecoder;
import java.net.http.HttpClient;
import java.net.http.HttpRequest;
import java.net.http.HttpResponse;
import java.nio.charset.StandardCharsets;
import java.time.Duration;
import java.util.Optional;
import java.util.logging.Level;
import java.util.logging.Logger;
public class SendGridRedirectResolver {
private static final Logger logger =
Logger.getLogger (SendGridRedirectResolver.class.getName());
private static final int MAX_REDIRECTS = 10;
private static final HttpClient CLIENT = HttpClient.newBuilder()
.connectTimeout (Duration.ofSeconds (60))
.followRedirects (HttpClient.Redirect.NEVER)
.build();
//DTOS (Modern Java Records)
public static class Input {
public String input_url;
}
public static class Result {
public String output_url;
public String uuid;
public String executionInfo;
}
// Entry method
public Result handleRequest (Input input) {
Result result = new Result();
try {
logger.log(Level.INFO, "OIC-Input URL: {0}", input.input_url);
System.out.println("OIC-Input URL: " + input.input_url);
String decodedUrl = extractFromUrlDefense (input.input_url);
logger.log (Level.INFO, "OIC-Decoded SendGrid URL: (0)", decodedUrl);
System.out.println("OIC-Decoded SendGrid URL : " + decodedUrl);
String finalUrl = resolveFinalUrl (decodedUrl);
logger.log (Level.INFO, "OIC-Final URL: (0)", finalUrl);
System.out.println("OIC-Final URL:: " + finalUrl);
result.output_url = finalUrl;
result.uuid = "";
result.executionInfo = "SUCCESS";
return result;
} catch (Exception e) {
result.executionInfo = e.getMessage();
logger.log (Level.SEVERE, "Processing failed", e);
System.out.println("OIC- Exception: "+ e);
return result;
}
}
// Core Logic
private static String extractFromUrlDefense (String url) {
int start = url.indexOf("/__");
int end = url.indexOf("__;");
if (start < 0 || end < 0 || end <= start + 3) {
throw new IllegalArgumentException("Invalid urldefense URL");
}
String encoded = url.substring(start + 3, end);
return URLDecoder.decode (encoded, StandardCharsets.UTF_8);
}
private static String resolveFinalUrl (String url) throws Exception {
URI current = URI.create(url);
for (int i = 0; i < MAX_REDIRECTS; i++) {
HttpRequest request = HttpRequest.newBuilder (current) .timeout(Duration.ofSeconds (60))
.GET()
.build();
HttpResponse<Void> response =
CLIENT.send(request, HttpResponse.BodyHandlers.discarding());
int status = response.statusCode();
if (status >= 300 && status < 400) {
Optional<String> location =
response.headers().firstValue("Location");
if (location.isEmpty()) {
throw new RuntimeException("Redirect without Location header");
}
current = current.resolve(location.get());
} else {
return current.toString();
}
}
throw new RuntimeException("Too many redirects");
}
// Standalone Test
public static void main(String[] args) {
String urlDefense =
"Paste your redirect url here";
Input input = new Input();
input.input_url = urlDefense;
SendGridRedirectResolver resolver = new SendGridRedirectResolver();
Result result = resolver.handleRequest(input);
System.out.println("output_url:" + result.output_url);
System.out.println("uuid:" + result.uuid);
}
}
Code link:
https://drive.google.com/file/d/1rXIeIGJ7QjhfUBau5OwXDsye4EKUYo17/view?usp=drivesdk
Snap of codes:
Deploying OCI Function
- Create an OCI Function Application
- Deploy the function using Fn CLI
- Expose it via OCI API Gateway
- Secure it using:
- OCI IAM
- API Key or OCI Resource Principal
- Calling OCI Function from OIC
Steps in OIC
Create a REST Adapter integration
Configure API Gateway endpoint
Pass the redirected URL as request payload
Receive response:
Json
{
"finalUrl": "https://example.com/path/uuid/12345"
}
Extracting Required Data in OIC
Once OIC receives the final URL:
Extract UUID or parameters
Continue downstream orchestration
Example:
substring-after(finalUrl, '/uuid/')
Benefits of This Approach
✅ Overcomes OIC redirect limitations
✅ Clean separation of concerns
✅ Serverless and cost-effective
✅ Reusable across multiple integrations
✅ Easy to maintain and enhance
Real-World Scenarios
Email tracking links (SendGrid, Twilio)
Microsoft Graph email body links
Payment gateway redirect URLs
Identity verification flows
Short URL expansion
Conclusion
Using OCI Functions as a redirect resolver is a simple yet powerful pattern when working with OIC. It keeps integrations clean, avoids complex workarounds, and provides full control over HTTP behavior.
If your OIC flow depends on the final destination URL, this approach is highly recommended.
Reference online tool java code run:
https://www.onlinegdb.com/online_java_compiler
