Shopify Bulk Sync

Use Cases:

• Tier launch/relaunch (thousands of customers)
• Mass metafield sync (point balance, tier info)
• Bulk customer tag updates
• Mass product metafield updates
• Initial data migration

File Size Limits & Chunking

Critical Limits:

JSONL Format

Each line must be a valid JSON object with variables for your mutation:

For metafieldsSet:

{"metafields":{"key":"points","namespace":"loyalty","ownerId":"gid://shopify/Customer/123","value":"500","type":"number_integer"}}
{"metafields":{"key":"points","namespace":"loyalty","ownerId":"gid://shopify/Customer/456","value":"750","type":"number_integer"}}

For customerUpdate (tags):

{"input":{"id":"gid://shopify/Customer/123","tags":["vip","gold-tier"]}}
{"input":{"id":"gid://shopify/Customer/456","tags":["member","silver-tier"]}}

Complete Flow

Step 1: Create Staged Upload

mutation {
  stagedUploadsCreate(input: [{
    resource: BULK_MUTATION_VARIABLES
    filename: "bulk-update.jsonl"
    mimeType: "text/jsonl"
    httpMethod: POST
  }]) {
    stagedTargets {
      url
      resourceUrl
      parameters { name value }
    }
    userErrors { field message }
  }
}

Step 2: Upload JSONL File

const formData = new FormData();

// Add all parameters from stagedTargets.parameters
stagedTarget.parameters.forEach(({name, value}) => {
  formData.append(name, value);
});

// Add the JSONL file
formData.append('file', Buffer.from(jsonlContent), {
  filename: 'bulk-update.jsonl',
  contentType: 'text/jsonl'
});

await fetch(stagedTarget.url, {method: 'POST', body: formData});

// Get the stagedUploadPath from the 'key' parameter
const stagedUploadPath = stagedTarget.parameters.find(p => p.name === 'key').value;

Step 3: Run Bulk Mutation

mutation {
  bulkOperationRunMutation(
    mutation: "mutation metafieldsSet($metafields: [MetafieldsSetInput!]!) { metafieldsSet(metafields: $metafields) { metafields { id } userErrors { field message } } }",
    stagedUploadPath: "tmp/your-staged-upload-path"
  ) {
    bulkOperation { id status }
    userErrors { field message }
  }
}

Step 4: Handle Completion Webhook

Subscribe to BULK_OPERATIONS_FINISH webhook:

// When webhook fires, check if more chunks needed
if (hasMoreChunks) {
  await uploadNextChunk(syncId, nextOffset);
} else {
  await updateStatus('completed');
}

Chunking Strategy

For datasets > 50K items, process in chunks:

const CHUNK_SIZE = 50000;

async function processBulkUpdate(items) {
  const totalChunks = Math.ceil(items.length / CHUNK_SIZE);

  for (let i = 0; i < totalChunks; i++) {
    const chunk = items.slice(i * CHUNK_SIZE, (i + 1) * CHUNK_SIZE);

    // Prepare JSONL for this chunk
    const jsonl = chunk.map(item => JSON.stringify({
      metafields: {
        key: 'points',
        namespace: 'loyalty',
        ownerId: `gid://shopify/Customer/${item.customerId}`,
        value: String(item.points),
        type: 'number_integer'
      }
    })).join('\n');

    // Upload and run bulk operation
    const result = await runBulkOperation(jsonl);

    // Save state for webhook continuation
    await saveChunkState({
      bulkOperationId: result.id,
      currentChunk: i,
      totalChunks,
      nextOffset: (i + 1) * CHUNK_SIZE
    });

    // Wait for webhook before next chunk
    break;
  }
}

Error Handling & Retry

async function uploadWithRetry(stagedTarget, jsonl, maxRetries = 3) {
  for (let attempt = 0; attempt < maxRetries; attempt++) {
    try {
      await uploadJSONL(stagedTarget, jsonl);
      return; // Success
    } catch (error) {
      const isRetryable = [400, 429, 500, 502, 503, 504].includes(error.status);

      if (isRetryable && attempt < maxRetries - 1) {
        const backoffMs = Math.pow(2, attempt + 1) * 1000;
        await delay(backoffMs);
        continue;
      }

      throw error;
    }
  }
}

Best Practices

DO:

• Use bulk operations for 500+ items
• Chunk at 50K lines per operation
• Buffer writes to storage
• Track progress state for webhook continuation
• Use exponential backoff for retries
• Clean up storage files after completion

DON'T:

• Use bulk operations for small batches (<100 items)
• Upload huge files without chunking (>100MB)
• Forget to handle BULK_OPERATIONS_FINISH webhook
• Write to storage on every iteration (buffer instead)
• Block waiting for bulk operation completion (use webhooks)

Decision Guide

How many items to update?
├── 1-50: Direct API calls
├── 50-500: Cloud Tasks with batched API calls
└── 500+: Shopify Bulk Operations API

Is it time-sensitive?
├── Yes (real-time): Cloud Tasks with batching
└── No (can wait minutes): Bulk Operations

Triggered by?
├── User action (sync button): Bulk Operations
├── Webhook (order): Cloud Tasks
└── Cron job (scheduled sync): Bulk Operations

Checklist

- Volume > 500 items? Use Bulk Operations
- JSONL files chunked at 50K lines max
- Staged uploads used (stagedUploadsCreate -> POST -> bulkOperationRunMutation)
- Storage buffering for large data collection
- Chunk state saved for webhook continuation
- BULK_OPERATIONS_FINISH webhook handler implemented
- Retry logic with exponential backoff
- Progress status saved for user visibility
- Cleanup: delete temp files after completion
```3a:["$","$L43",null,{"content":"$44","frontMatter":{"name":"shopify-bulk-sync","description":"Use this skill when the user asks about \"bulk operations\", \"mass update\", \"bulk mutation\", \"JSONL\", \"staged uploads\", \"large data sync\", \"tier launch\", or any large-scale Shopify data operations. Provides Bulk Operations API patterns for processing thousands of items."}}]