HTTP Interfaces and External Systems for Vehicle Due Diligence Reports

Data for vehicle due diligence reports primarily comes from vehicle management registration systems, third-party vehicle condition inspection

What data for this category looks like

Data for vehicle due diligence reports primarily comes from vehicle management registration systems, third-party vehicle condition inspection agencies, dealer inventory databases, and insurance claims records. Updates are triggered by changes to vehicle status, including real-time updates for events such as vehicle transfer, accidents, and annual inspections. The daily batch sync frequency is once per day.

The document structure includes five modules: core identifier fields, basic attributes, vehicle condition inspection details, ownership certificates, and historical accident records. Fields include a 17-character VIN code (string type), driving mileage (unit: kilometers), paint thickness (unit: micrometers), engine number (string type), and more. Some nested fields, such as vehicle condition inspection sub-items, require hierarchical parsing.

What constraints do these characteristics impose on HTTP interfaces and external systems

The VIN code as the unique identifier requires interfaces to support exact match queries. Fuzzy matching logic must not be used, to avoid data confusion.

Nested vehicle condition inspection fields require the JSON structure returned by the HTTP interface to support multi-level parsing. External systems must correctly pass field mapping rules when making calls.

Long documents with multi-dimensional data lead to longer request and response latency than generic document interfaces. Longer timeout windows must be reserved.

Mandatory field units require external systems to perform uniform conversion when passing or pulling data, to avoid parsing errors caused by unit mismatches.

For batch sync scenarios, interface pull support for pagination is required to adapt to daily full data update needs.

How to set configurations

Configuration ItemRecommended ValueRationale
PARSE_FILE_TIMEOUT_SECONDS300 secondsVehicle due diligence report documents are lengthy, contain multi-page vehicle condition inspection content, and have longer parsing time than generic documents
API_REQUEST_TIMEOUT180 secondsSufficient time must be reserved for full data pulling when calling third-party vehicle condition data source interfaces
UPLOAD_FILE_MAX_SIZE15 MBA single vehicle due diligence report PDF or structured file typically does not exceed 15 MB, to support batch import
REQUEST_RETRY_TIMES2 timesSome third-party vehicle data interfaces have temporary fluctuations; retries can reduce the probability of query failures
FIELD_MAPPING_MODEUniquely bound by VIN codeVehicle data uses the 17-character VIN code as the unique identifier, and field mapping rules must be strictly matched
WEBHOOK_VERIFY_KEYGenerate a dedicated key for the connected systemVerify the legitimacy of callback requests initiated by external systems, to ensure data transmission security

The parameter values provided on this page are common starting points for configuration. Actual values are affected by material format, data volume and business rules. Specific issues require specific analysis. It is recommended to test on your own samples before finalizing settings.

Three common mistakes

  • Phenomenon: When calling an external vehicle data source interface, the console outputs Api response error: undefined with no valid response content. Cause: No reasonable API_REQUEST_TIMEOUT is configured. The return time of the third-party vehicle condition data interface exceeds the set threshold, and the connection is forcibly disconnected.
  • Phenomenon: After importing a vehicle due diligence report PDF, core fields such as VIN code and mileage are empty. Cause: The enable_pdf_structured_parse parameter is not specified in the API request for creating a file collection. The default parsing mode does not recognize fixed fields in structured reports.
  • Phenomenon: After configuring a webhook callback, no notification of completed due diligence report generation is received. Cause: WEBHOOK_VERIFY_KEY is not set, or the configured key does not match the signature generated by the external system, and the request is blocked by security measures.

How to confirm configuration is complete

  • Initiate a single VIN code query request, check whether the response body contains complete basic vehicle information and vehicle condition inspection data fields, and whether the field units meet preset requirements.
  • Upload a standard vehicle due diligence report PDF, check whether the parsed structured data contains nested paint and engine parameter sub-fields.
  • Configure a test webhook address, initiate a simulated callback request, check whether the target address receives a legitimate request that has passed signature verification.
  • View the interface call log, confirm that the number of retries does not exceed the preset REQUEST_RETRY_TIMES, and there are no consecutive timeout errors.

Question material comes from public community discussions. Configuration values are common starting points and should be measured against your own samples. Verified on 2026-09-14.