The V2 Records API provides an interface for reading and writing records from Flatfile sheets. It is optimized for performance when working with large numbers of records.
Support for the V2 Records API was added to the @flatfile/api package in version 1.18.0.

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Overview

The V2 Records API is accessible through the records.v2 property on the Flatfile client. 
import { FlatfileClient } from "@flatfile/api";
const client = new FlatfileClient({ token: "YOUR_TOKEN" });
await client.records.v2.get("us_sh_1234abcd")
The V2 API uses a specialized JSON Lines (JSONL) format that is optimized for performance and usage with streaming requests.

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Reading Records

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getRaw()

Retrieve records from a sheet in raw JSONL format. 
getRaw(
  sheetId: Flatfile.SheetId,
  options?: GetRecordsRequestOptions,
  requestOptions?: RequestOptions
): Promise<JsonlRecord[]>
Returns an array of JsonlRecord objects containing the raw data structure from the API including special fields like __k (record ID), __v (version), etc. Example: 
const rawRecords = await api.records.v2.getRaw('us_sh_123', {
  fields: ['firstName', 'lastName'],
  pageSize: 1000
});

rawRecords.forEach(record => {
  console.log(`Record ID: ${record.__k}`);
  console.log(`Field values:`, record);
});

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getRawStreaming()

Stream records from a sheet in raw JSONL format. 
getRawStreaming(
  sheetId: Flatfile.SheetId,
  options?: GetRecordsRequestOptions,
  requestOptions?: RequestOptions
): AsyncGenerator<JsonlRecord>
The most memory-efficient way to process large datasets as records are yielded individually. Example: 
for await (const rawRecord of api.records.v2.getRawStreaming('us_sh_123', {
  includeTimestamps: true
})) {
  console.log(`Record ID: ${rawRecord.__k}`);
  console.log(`Updated at: ${rawRecord.__u}`);
  // Process each record as it streams in
}

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Writing Records

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writeRaw()

Write records to a sheet in raw JSONL format. 
writeRaw(
  records: JsonlRecord[],
  options?: WriteRecordsRequestOptions,
  requestOptions?: RequestOptions
): Promise<WriteRecordsResponse>
Parameters:
  • records - Array of JsonlRecord objects to write
  • options - Write configuration options
  • requestOptions - Optional request configuration
Example: 
const records: JsonlRecord[] = [
  { firstName: 'John', lastName: 'Doe', __s: 'us_sh_123' },
  { __k: 'us_rc_456', firstName: 'Jane', lastName: 'Smith' }  // Update existing
];

const result = await api.records.v2.writeRaw(records, {
  sheetId: 'us_sh_123',
  truncate: false
});

console.log(`Created: ${result.created}, Updated: ${result.updated}`);

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writeRawStreaming()

Stream records to a sheet in raw JSONL format. 
writeRawStreaming(
  recordsStream: AsyncIterable<JsonlRecord>,
  options?: WriteStreamingOptions,
  requestOptions?: RequestOptions
): Promise<WriteRecordsResponse>
Efficiently write large datasets by streaming records to the server. Example: 
async function* generateRecords() {
  for (let i = 0; i < 100000; i++) {
    yield {
      firstName: `User${i}`,
      email: `user${i}@example.com`,
      __s: 'us_sh_123'
    };
  }
}

const result = await api.records.v2.writeRawStreaming(generateRecords(), {
  sheetId: 'us_sh_123',
  chunkSize: 1000,
  useBodyStreaming: 'auto'
});

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JSONL Record Format Reference

The V2 Records API uses JSONL (JSON Lines) format for raw record operations. JSONL is a text format where each line is a valid JSON object representing a single record.

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Special Fields

Flatfile uses special fields prefixed with __ (double underscore) to store metadata and system information:
FieldDescriptionExample
__kRecord ID (unique identifier)"us_rc_123456"
__nkNew record ID (for creation)"temp_123"
__vRecord version ID"v_789"
__sSheet ID"us_sh_123"
__nSheet slug"contacts"
__cRecord configuration{"locked": true}
__mRecord metadata{"source": "import"}
__iValidation messages{"email": [{"type": "error", "message": "Invalid format"}]}
__dDeleted flagtrue
__eValid flagfalse
__lLinked records[{...}]
__uUpdated timestamp"2023-11-20T16:59:40.286Z"
Note that many special fields will not be included unless the corresponding query parameter is included, such as includeMessages to include the __i field with validation messages.

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Field Values

Regular field values are stored directly as properties on the JSONL record: 
{
  "__k": "us_rc_123456",
  "__s": "us_sh_123",
  "firstName": "John",
  "lastName": "Doe",
  "email": "john.doe@example.com",
  "age": 30,
  "isActive": true
}

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Validation Messages

If included, the __i field contains validation messages for fields that have errors or warnings. The messages are structured as an array of objects. Each validation message object will be structured as {"x": <field key of message>, "m": <validation message>}. 
{
  "__k": "us_rc_123456",
  "__s": "us_sh_123",
  "email": "invalid-email",
  "__i": [
    {"x": "firstName", "m": "First name is required"},
    {"x": "email", "m": "Not a valid email address"}
  ]
}

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Complete Example

A complete JSONL record with all common fields: 
{
  "__k": "us_rc_123456",
  "__v": "v_789",
  "__s": "us_sh_123",
  "__n": "contacts",
  "__c": {
    "locked": false,
    "priority": "high"
  },
  "__m": {
    "source": "api_import",
    "batch_id": "batch_001"
  },
  "__i": [
    {"x": "firstName", "m": "First name is required"},
    {"x": "email", "m": "Not a valid email address"}
  ],
  "__e": true,
  "__u": "2023-11-20T16:59:40.286Z",
  "firstName": "John",
  "lastName": "Doe",
  "email": "john.doe@example.com",
  "company": "Acme Corp",
  "phone": "+1-555-123-4567"
}

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Record Operations

The V2 write records endpoint can be used to create, update, or delete records into a sheet all in a single request. The operation performed depends on which special keys are provided.

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Create New Record

To create a new record, the record can simply be passed with a sheet ID in __s and no record ID. 
{
  "__s": "us_sh_123",
  "firstName": "New",
  "lastName": "User"
}

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Update Existing Record

To update an existing record, provide the record ID in the __k field. 
{
  "__k": "us_rc_123456",
  "__s": "us_sh_123",
  "firstName": "Updated",
  "lastName": "Name"
}

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Delete Record

To delete a record, provide the record ID in the __k field and pass the delete flag in the __d field. 
{
  "__k": "us_rc_123456",
  "__s": "us_sh_123",
  "__d": true
}