Overview

Tag existence checking operations provide a lightweight and efficient way to verify whether specific tags exist in your graph database without retrieving their full data. This functionality is essential for validation, conditional operations, and optimizing API calls by avoiding unnecessary data transfer. Understanding tag existence checking is crucial for building robust applications that need to validate tag presence before performing operations.

Key capabilities include:

Checking tag existence using lightweight HEAD requests
Validating tag GUIDs before performing operations
Optimizing API calls by avoiding full data retrieval
Supporting conditional logic based on tag presence
Providing fast existence verification for large datasets

These operations support various use cases such as data validation, conditional processing, API optimization, and building robust error handling mechanisms.

Check Tag Existence

Check if a tag exists using HEAD: /v1.0/tenants/{tenant-guid}/tags/{tag-guid}. This endpoint performs a lightweight existence check without returning the tag data, making it ideal for validation and conditional operations.

curl --location --head 'http://localhost:8701/v1.0/tenants/00000000-0000-0000-0000-000000000000/tags/00000000-0000-0000-0000-000000000000' \
--header 'Authorization: ••••••'

import { LiteGraphSdk } from "litegraphdb";

var api = new LiteGraphSdk(
  "http://localhost:8701/",
  "<Tenant-Guid>",
  "*******"
);

const existsTag = async () => {
  try {
    const data = await api.Tag.exists("<tag-guid>");
    console.log(data, "check data");
  } catch (err) {
    console.log("err:", JSON.stringify(err));
  }
};

import litegraph

sdk = litegraph.configure(
    endpoint="http://localhost:8701",
    tenant_guid="Tenant-Guid",
    access_key="******",
)

def exists_tag():
    exists = litegraph.Tag.exists(guid="tag-guid")
    print(exists)

exists_tag()

using LiteGraph;
using LiteGraph.GraphRepositories.Sqlite;

LiteGraphClient liteGraph = new LiteGraphClient(new SqliteGraphRepository("litegraph.db"));
liteGraph.InitializeRepository();
bool exists = liteGraph.Tag.ExistsByGuid(Guid.Parse("<tenant-guid>"), 
                                         Guid.Parse("<tag-guid>"));

Response

The API returns different status codes based on tag existence:

200 OK: Tag exists and is accessible
404 Not Found: Tag does not exist or is not accessible

Next Steps

After checking tag existence, consider these next actions:

Conditional Operations: Perform different actions based on existence results
Create Missing Tags: Create tags that don't exist if needed
Update Existing Tags: Modify tags that already exist