How to fix IndexNotFoundException: no such index [index_name] in Elasticsearch

# Check if a specific index exists
curl -X GET "localhost:9200/my-index" -u "username:password"

# Check multiple indices
curl -X GET "localhost:9200/index1,index2,index3" -u "username:password"

# Use HEAD request for simple existence check (returns 200 if exists, 404 if not)
curl -X HEAD "localhost:9200/my-index" -u "username:password"

# List all indices in the cluster
curl -X GET "localhost:9200/_cat/indices?v" -u "username:password"

# List indices with specific pattern
curl -X GET "localhost:9200/_cat/indices/my-*?v" -u "username:password"

# Basic index creation
curl -X PUT "localhost:9200/my-index" -u "username:password" -H 'Content-Type: application/json' -d'
{
  "settings": {
    "number_of_shards": 1,
    "number_of_replicas": 1,
    "index": {
      "refresh_interval": "1s"
    }
  },
  "mappings": {
    "properties": {
      "title": {
        "type": "text",
        "fields": {
          "keyword": {
            "type": "keyword",
            "ignore_above": 256
          }
        }
      },
      "timestamp": {
        "type": "date"
      }
    }
  }
}
'

# For time-series data, consider using data streams
curl -X PUT "localhost:9200/_index_template/my-template" -u "username:password" -H 'Content-Type: application/json' -d'
{
  "index_patterns": ["logs-*"],
  "data_stream": {},
  "priority": 200,
  "template": {
    "settings": {
      "number_of_shards": 1,
      "number_of_replicas": 1
    }
  }
}
'

# Then create the data stream
curl -X PUT "localhost:9200/_data_stream/logs-app" -u "username:password"

# Check current auto-create setting
curl -X GET "localhost:9200/_cluster/settings?include_defaults=true&filter_path=**.action.auto_create_index" -u "username:password"

# Enable auto-create for specific index patterns
curl -X PUT "localhost:9200/_cluster/settings" -u "username:password" -H 'Content-Type: application/json' -d'
{
  "persistent": {
    "action.auto_create_index": "my-index-*,logs-*,-.*,+*"
  }
}
'

# Enable auto-create for all indices (not recommended for production)
curl -X PUT "localhost:9200/_cluster/settings" -u "username:password" -H 'Content-Type: application/json' -d'
{
  "persistent": {
    "action.auto_create_index": "true"
  }
}
'

# Disable auto-create (default in production)
curl -X PUT "localhost:9200/_cluster/settings" -u "username:password" -H 'Content-Type: application/json' -d'
{
  "persistent": {
    "action.auto_create_index": "false"
  }
}

# Create an alias pointing to your index
curl -X POST "localhost:9200/_aliases" -u "username:password" -H 'Content-Type: application/json' -d'
{
  "actions": [
    {
      "add": {
        "index": "my-index-2024.01.01",
        "alias": "current-index"
      }
    }
  ]
}
'

# Query using the alias
curl -X GET "localhost:9200/current-index/_search" -u "username:password" -H 'Content-Type: application/json' -d'
{
  "query": {
    "match_all": {}
  }
}
'

# Switch alias to new index (zero downtime)
curl -X POST "localhost:9200/_aliases" -u "username:password" -H 'Content-Type: application/json' -d'
{
  "actions": [
    {
      "remove": {
        "index": "my-index-2024.01.01",
        "alias": "current-index"
      }
    },
    {
      "add": {
        "index": "my-index-2024.01.02",
        "alias": "current-index"
      }
    }
  ]
}
'

# Check which indices an alias points to
curl -X GET "localhost:9200/_alias/current-index" -u "username:password"

// Example: Check index existence before operations
const { Client } = require('@elastic/elasticsearch');
const client = new Client({ node: 'http://localhost:9200' });

async function safeIndexOperation(indexName, document) {
  try {
    // Check if index exists
    const exists = await client.indices.exists({ index: indexName });

    if (!exists) {
      console.log('Index ' + indexName + ' doesn\'t exist. Creating...');

      // Create index with default settings
      await client.indices.create({
        index: indexName,
        body: {
          settings: {
            number_of_shards: 1,
            number_of_replicas: 1
          }
        }
      });

      console.log('Index ' + indexName + ' created successfully.');
    }

    // Now perform the operation
    const response = await client.index({
      index: indexName,
      body: document
    });

    return response;
  } catch (error) {
    if (error.meta?.body?.error?.type === 'index_not_found_exception') {
      console.error('Index ' + indexName + ' not found. Please create it first.');
      // Implement retry logic or fallback
    }
    throw error;
  }
}

// Example: Bulk operations with error handling
async function safeBulkOperation(operations) {
  const response = await client.bulk({
    body: operations,
    refresh: true
  });

  if (response.errors) {
    const failedIndices = new Set();

    // Check for index not found errors
    response.items.forEach(item => {
      if (item.index?.error?.type === 'index_not_found_exception') {
        const indexName = item.index.error.index;
        failedIndices.add(indexName);
      }
    });

    // Handle missing indices
    for (const indexName of failedIndices) {
      console.log('Creating missing index: ' + indexName);
      await client.indices.create({ index: indexName });
    }

    // Retry failed operations
    if (failedIndices.size > 0) {
      return await client.bulk({
        body: operations,
        refresh: true
      });
    }
  }

  return response;
}