apache/pulsar · error · ParameterException

Could not apply regex when read topics from file.

Error message

Could not apply regex when read topics from file.

What it means

In CmdTopics.DeleteCmd, --read-from-file (which reads topic names line-by-line from a file) is mutually exclusive with --regex pattern matching; combining them is ambiguous and rejected up front with this ParameterException. No topics are deleted when this fires.

Source

Thrown at pulsar-client-tools/src/main/java/org/apache/pulsar/admin/cli/CmdTopics.java:633

                "--force" }, description = "Close all producer/consumer/replicator and delete topic forcefully")
        private boolean force = false;

        @Option(names = {"-d", "--deleteSchema"}, description = "Delete schema while deleting topic, "
                + "but the parameter is invalid and the schema is always deleted", hidden = true)
        private boolean deleteSchema = false;

        @Option(names = {"-r", "regex"},
                description = "Use a regex expression to match multiple topics for deletion.")
        boolean regex = false;

        @Option(names = {"--from-file"}, description = "Read a list of topics from a file for deletion.")
        boolean readFromFile;


        @Override
        void run() throws PulsarAdminException, IOException {
            if (readFromFile && regex) {
                throw new ParameterException("Could not apply regex when read topics from file.");
            }
            if (readFromFile) {
                List<String> topicsFromFile = Files.readAllLines(Path.of(topic));
                for (String t : topicsFromFile) {
                    try {
                        getTopics().delete(t, force);
                    } catch (Exception e) {
                        print("Failed to delete topic: " + t + ". Exception: " + e);
                    }
                }
            } else {
                String topicName = validateTopicName(topic);
                if (regex) {
                    String namespace = TopicName.get(topic).getNamespace();
                    List<String> topics = getTopics().getList(namespace);
                    topics = topics.stream().filter(s -> s.matches(topicName)).toList();
                    for (String t : topics) {
                        try {

View on GitHub (pinned to 820761864e)

Solutions

1. Remove the --regex flag and put literal topic names in the file, or
2. Remove --read-from-file and pass the regex pattern directly as the topic argument
3. Split the operation: filter the file first, then delete with literal names

Example fix

// before
pulsar-admin topics delete --read-from-file topics.txt --regex 'my-tenant/ns/.*'
// after
pulsar-admin topics delete --read-from-file topics.txt
// or
pulsar-admin topics delete 'my-tenant/ns/.*' --regex

if (readFromFile && regex) throw new IllegalArgumentException("--read-from-file and --regex are mutually exclusive");

When it happens

Trigger: Running 'pulsar-admin topics delete' with both --read-from-file and --regex flags present, e.g. a script accumulated flags from two different invocation styles.

Common situations: Wrapper scripts that always append --regex while adding --read-from-file for bulk deletions; users thinking the file contents can be regex patterns; copy-paste merging of two example commands.

Related errors

• Need to provide a persistent topic name
• Need to provide a non-persistent topic name
• Invalid message id (must be in format: ledgerId:entryId) val
• Illegal auth action '${action}'. Possible values: ${Arrays.t
• Invalid key value pair '${property}', valid format like 'a=b

AI-assisted analysis of apache/pulsar@820761864e (2026-09-06). Data as JSON: /api/errors/a8b12034bad086b5. Report an issue: GitHub.