What Data for This Category Looks Like
Metallurgical coal financial report data is primarily sourced from public periodic reports of listed companies disclosed by domestic and overseas exchanges, and monitoring datasets released by coal industry associations. Two update cadences apply: Quarterly financial reports are updated within 30 days after the end of each quarter. Annual financial reports are updated within 120 days after the end of each year. Supporting industry supply and demand data is updated daily. Public documents mainly include periodic reports in PDF format and structured JSON datasets. Core fields include report period, actual metallurgical coal output, domestic and overseas sales volume, weighted average selling price, unit production cost, and more. Output is measured in ten thousand tons, selling price in yuan per ton. Some fields include year-over-year and month-over-month change ranges.
Constraints for HTTP Interfaces and External Systems
The category specificity, fixed update cadence, and multi-format nature of metallurgical coal financial report data create multiple constraints for HTTP interface and external system integration. Add category filtering parameters to interface requests to only pull metallurgical coal-related data, and avoid mixing in data from other coal categories. Interfaces that query by report period range must support exact matching and interval filtering for the report period field, to align with the update cadence of periodic financial reports. Support pulling both structured API data and unstructured PDF financial report documents, and configure different request headers and parsing rules for each. Additionally, supporting industry data for metallurgical coal has a high update frequency. Set a reasonable cache expiration duration in external systems to balance data timeliness and request load.
Configuration Settings
| Configuration Item | Recommended Value | Rationale |
|---|---|---|
external_api_filter | {"coal_type": "metallurgical_coal", "data_type": "financial_report"} | Restrict to metallurgical coal financial reports to avoid pulling data from other coal categories or non-financial report data |
external_api_timeout | 600 seconds | Annual metallurgical coal financial report PDFs have large file sizes, and full pulling and parsing require a longer response time |
PARSE_FILE_MAX_SIZE | 20 MB | Publicly disclosed PDF financial reports for listed metallurgical coal companies typically do not exceed 20 MB; exceeding the threshold will trigger interface interception |
cache_ttl_external_data | 86400 seconds | Supporting industry supply and demand data for metallurgical coal is updated daily, caching for one day balances timeliness and request frequency |
retry_count_on_fail | 3 retries | Exchange disclosure interfaces may experience temporary fluctuations, and retries reduce the probability of single request failure |
response_field_mapping | {"产量": "output", "售价": "avg_price", "报告期": "report_date"} | Map industry terms for metallurgical coal financial report fields to ensure consistent field names across external systems |
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 individual analysis, and it is recommended to test against your own samples before finalizing.
Three Common Misconfigurations
- Symptom: Interface request returns
500 do request failed: Post "https://xxx" tls: failed to verify certificate. Cause: TLS certificate verification rules for external interfaces are not configured, or the certificate has expired or the domain name does not match, resulting in HTTPS request interception. - Symptom: External system scheduled pulls of metallurgical coal financial report data trigger a large number of abnormal requests leading to quota exhaustion. Cause: Request rate limits are not set, and update periods for financial report data are not distinguished, resulting in repeated pulls during non-working hours.
- Symptom: Core output fields are empty after parsing metallurgical coal financial report documents. Cause: Category filtering parameters are not configured, resulting in pulling non-matching data from other coal categories and causing field parsing failures.
How to Verify Proper Configuration
- Send a test request with preset filtering parameters, and check that returned results only include metallurgical coal-related financial report data.
- Upload a public metallurgical coal financial report PDF file, and verify that extracted fields match the configured mapping rules.
- Check system request logs to confirm that request rates align with preset limits, with no abnormal high-frequency requests.
- Trigger a request that exceeds the timeout threshold, and confirm that the system returns a clear timeout prompt instead of hanging.
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.