appsmithorg/appsmith · error · AppsmithPluginException

PE-ARG-5000

PE-ARG-5000

Error message

Appsmith server has encountered an unexpected error when establishing connection with AWS S3 server. Please reach out to Appsmith customer support to resolve this.

What it means

Argument error (`PLUGIN_EXECUTE_ARGUMENT_ERROR`, PE-ARG-5000) from `listAllFilesInBucket`: the `AmazonS3 connection` parameter is null. The connection object is built upstream from the datasource configuration (access key, secret key, region, endpoint), so a null here means connection creation silently failed. Note the message ('connection with AWS S3 server') describes the symptom even though the code classifies it as an argument error.

Source

Thrown at app/server/appsmith-plugins/amazons3Plugin/src/main/java/com/external/plugins/AmazonS3Plugin.java:171

                        S3ErrorMessages.FILE_CONTENT_FETCHING_ERROR_MSG);
            }

            ArrayList<String> result = new ArrayList<>();
            List<S3ObjectSummary> objects = objectListing.getObjectSummaries();
            for (S3ObjectSummary os : objects) {
                result.add(os.getKey());
            }

            return result;
        }

        /*
         * - Exception thrown by this method is expected to be handled by the caller.
         */
        ArrayList<String> listAllFilesInBucket(AmazonS3 connection, String bucketName, String prefix)
                throws AppsmithPluginException {
            if (connection == null) {
                throw new AppsmithPluginException(
                        AppsmithPluginError.PLUGIN_EXECUTE_ARGUMENT_ERROR, S3ErrorMessages.CONNECTIVITY_ERROR_MSG);
            }

            if (bucketName == null) {
                /*
                 * - bucketName is NOT expected to be null at this program point. A null check has been added in the
                 *  execute function already.
                 */
                throw new AppsmithPluginException(
                        AppsmithPluginError.PLUGIN_EXECUTE_ARGUMENT_ERROR, S3ErrorMessages.EMPTY_BUCKET_ERROR_MSG);
            }

            if (prefix == null) {
                /*
                 * - prefix is NOT expected to be null at this program point. A null check has been added in the
                 *  execute function already.
                 */
                throw new AppsmithPluginException(

View on GitHub (pinned to 8cd9021c24)

Solutions

1. Open the S3 datasource configuration and verify Access Key, Secret Key, and Region are all set and correct.
2. If using a custom S3-compatible provider, check the Endpoint URL and the S3 service provider selection.
3. Use the datasource 'Test' button - it exercises connection creation and surfaces the real underlying error.
4. Ensure the AWS SDK / S3 driver is on the classpath of the running Appsmith instance.

AmazonS3 connection = buildS3Client(datasource);
if (connection == null) {
    throw new IllegalArgumentException(
        "S3 connection could not be created. Check access key, secret key, region, "
        + "and endpoint URL in the datasource configuration.");
}
return s3Executor.listAllFilesInBucket(connection, bucketName, prefix);

private static boolean isUsableS3Client(AmazonS3 client) {
    if (client == null) return false;
    try { client.getS3AccountOwner(); return true; }
    catch (Exception e) { return false; }
}

When it happens

Trigger: Calling `listAllFilesInBucket` (directly or via the List Files query action) when `AmazonS3ClientBuilder` could not construct a client from the datasource - typically because credentials, region, or endpoint URL are missing/invalid, or because the S3 driver class failed to load.

Common situations: Missing or wrong AWS access/secret key in the datasource; empty region; incorrect endpoint URL for an S3-compatible provider; the S3 driver class not loaded (see `S3_DRIVER_LOADING_ERROR_MSG`); test/degraded environments where credentials were not injected.

Related errors

• PE-AS3-5000
• PE-DSE-5000
• PE-DSE-5003
• PE-DSE-5003
• PE-DSE-5003

AI-assisted analysis of appsmithorg/appsmith@8cd9021c24 (2026-08-12). Data as JSON: /api/errors/b81181558d434b4d. Report an issue: GitHub.