Gracefully Broken Pdf Download May 2026

async function downloadPDF() const response = await fetch('/api/generate-pdf', method: 'POST', body: formData ); const contentType = response.headers.get('content-type'); if (contentType.includes('application/json')) const error = await response.json(); showGracefulFailureDialog(error); return;

Some browsers treat 4xx/5xx responses as download failures and show generic "Failed – Network error". Step 3: Graceful Failure Response on Frontend When receiving a JSON error instead of a PDF blob, show a user‑friendly overlay. gracefully broken pdf download

Content-Type: application/json

function showGracefulFailureDialog(error) const dialog = <div class="pdf-error-card"> <h3>⚠️ PDF could not be generated</h3> <p>$error.message</p> $error.recoverable ? '<button onclick="retryPDF()">Try again</button>' : '' <button onclick="exportRawData()">Download data as CSV/JSON</button> <button onclick="contactSupport()">Report issue</button> <details> <summary>Technical details</summary> <pre>$error.code</pre> </details> </div> ; showModal(dialog); ' : '' &lt

// Normal PDF download const blob = await response.blob(); const url = URL.createObjectURL(blob); const a = document.createElement('a'); a.href = url; a.download = 'report.pdf'; a.click(); URL.revokeObjectURL(url); Download data as CSV/JSON&lt

// Frontend / API validation example function validatePDFRequest(data) const issues = []; if (!data.content) issues.push("No content provided"); if (data.content?.length > 500_000) issues.push("Content too large (>500k chars)"); if (data.images?.some(img => img.size > 10_000_000)) issues.push("Image exceeds 10MB limit"); return issues;

# DON'T DO THIS output = BytesIO() pdf = canvas.Canvas(output) pdf.drawString(100, 750, "Report") # crash here – user gets zero-byte or partial PDF