PDF Font Correction

Overview

If your PDF font correction request is unauthenticated or missing document identifiers, the service cannot deterministically map glyphs to the target font pipeline. This section specifies how to authenticate requests, upload a source PDF, and provide the document metadata needed for font correction.

Quick Reference

• Base URL: `https://api.pdffontcorrection.example/v1`
• Authentication: `Authorization: Bearer `
• Upload endpoint: `POST /documents:upload`
• Correct fonts endpoint (typically called after upload): `POST /documents/{documentId}:correct`
• Upload content type: `multipart/form-data`
• Idempotency: `Idempotency-Key` header (recommended)

Parameters

Code Example

# 1) Upload the source PDF (multipart/form-data)
curl -sS -X POST "https://api.pdffontcorrection.example/v1/documents:upload" \
  -H "Authorization: Bearer $API_KEY" \
  -H "Idempotency-Key: 9b7f1b2a-3a7c-4c4f-8a1c-2b6c0e0f6b11" \
  -F "file=@/path/to/source.pdf;type=application/pdf"

# 2) Correct fonts using the uploaded documentId
curl -sS -X POST "https://api.pdffontcorrection.example/v1/documents/{documentId}:correct" \
  -H "Authorization: Bearer $API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "targetFontProfile": "embed-substitute",
    "sourcePageRange": "1-5",
    "preserveLayout": true,
    "outputFormat": "pdf"
  }'

// Note: Replace {documentId} with the value returned from the upload response.

Response Format

{
  "upload": {
    "documentId": "doc_01J7K3Q2H9T4Z8WQK5M2P1A7B4",
    "status": "stored",
    "original": {
      "fileName": "source.pdf",
      "pageCount": 12,
      "contentType": "application/pdf",
      "sha256": "e3b0c44298fc1c149afbf4c8996fb924..."
    }
  },
  "correction": {
    "jobId": "job_01J7K3Q2H9T4Z8WQK5M2P1A7B5",
    "status": "queued",
    "estimatedSeconds": 18,
    "download": {
      "statusUrl": "https://api.pdffontcorrection.example/v1/jobs/job_.../status"
    }
  }
}

Notes & Best Practices

• Rate limits: Enforce client-side throttling; burst uploads can return `429 Too Many Requests`. Use backoff with jitter and reuse `Idempotency-Key` for retries.
• Authentication: Requests must include `Authorization: Bearer `. Missing or malformed tokens result in `401 Unauthorized`.
• Upload validation: The service expects a real PDF stream (`application/pdf`). Non-PDF uploads typically fail with `400 InvalidFileFormat`.
• Deterministic targeting: Use a consistent `targetFontProfile` across retries so font substitution and metric handling remain stable, especially when only a `sourcePageRange` is specified.

This setup establishes the authenticated boundary and the document identifiers the correction pipeline relies on; the next chapter defines how to choose and standardize font profiles for consistent results across documents.