apache/druid · error · IAE

External HTTP tables must provide either a URI or a

Error message

External HTTP tables must provide either a URI or a %s property

What it means

Thrown by HttpInputSourceDefn.validate when an external HTTP table specifies neither a URI nor the uriTemplate property. An HTTP input source must know which endpoint(s) to fetch data from, so at least one addressing mechanism is mandatory.

Solutions

Set the 'uris' field on the HTTP input source, e.g. ["https://example.com/data.json"]
Alternatively set the uriTemplate property on the table for parameterized URLs
Re-check the table definition JSON to confirm the address field survived serialization

Example fix

// before
{"type": "http"}
// after
{"type": "http", "uris": ["https://example.com/data.json"]}

Defensive patterns

Strategy: validation

Validate before calling

boolean ok = inputSource.getUris() != null && !inputSource.getUris().isEmpty() || tableProps.containsKey("uriTemplate");

Prevention

Always define either uris or uriTemplate for HTTP tables
Review table JSON before submitting
Use schema-aware editors that flag empty sources

When it happens

Trigger: Validating a catalog HTTP external table where the resolved table has no 'uris' field in its input source map and no uriTemplate table property set.

Common situations: Creating an external HTTP table spec and forgetting to fill in the address entirely; copying a template-based table definition and deleting both the template and URI fields; programmatic table construction that skipped the location property.

Understand the failure class

Background: "is required", "must be set", "missing required field": configuration validation errors across open-source libraries — this error's family across 36 libraries.

Related errors

AI-assisted analysis of apache/druid@9b90983fd2 (2026-09-07). Data as JSON: /api/errors/009c48fab96fb331. Report an issue: GitHub.

Appendix: source

Thrown at server/src/main/java/org/apache/druid/catalog/model/table/HttpInputSourceDefn.java:143

  @Override
  protected Class<? extends InputSource> inputSourceClass()
  {
    return HttpInputSource.class;
  }

  @Override
  public void validate(ResolvedExternalTable table)
  {
    final Map<String, Object> sourceMap = table.inputSourceMap;
    final boolean hasUri = sourceMap.containsKey(URIS_FIELD);
    final String uriTemplate = table.resolvedTable().stringProperty(URI_TEMPLATE_PROPERTY);
    final boolean hasTemplate = uriTemplate != null;
    final boolean hasFormat = table.inputFormatMap != null;
    final boolean hasColumns = !CollectionUtils.isNullOrEmpty(table.resolvedTable().spec().columns());

    if (!hasUri && !hasTemplate) {
      throw new IAE(
          "External HTTP tables must provide either a URI or a %s property",
          URI_TEMPLATE_PROPERTY
      );
    }
    if (hasUri && hasTemplate) {
      throw new IAE(
          "External HTTP tables must provide only one of a URI or a %s property",
          URI_TEMPLATE_PROPERTY
      );
    }
    if (hasUri && !hasFormat) {
      throw new IAE(
          "An external HTTP table with a URI must also provide the corresponding format"
      );
    }
    if (hasUri && !hasColumns) {
      throw new IAE(
          "An external HTTP table with a URI must also provide the corresponding columns"

View on GitHub (pinned to 9b90983fd2)