> ## Documentation Index
> Fetch the complete documentation index at: https://opendata.dev/docs/llms.txt
> Use this file to discover all available pages before exploring further.

# Scan entries

> Scan log entries for a given key within an optional sequence range.

Supports **long-polling**: set `follow=true` to hold the connection open
until new data arrives or `timeout_ms` elapses (default 30 000 ms). This
is useful for tailing a log stream in near-real-time.




## OpenAPI

````yaml /openapi/log.yaml get /api/v1/log/scan
openapi: 3.1.0
info:
  title: OpenData Log API
  version: 1.0.0
  description: HTTP API for the OpenData Log service — an append-only, key-partitioned log.
servers:
  - url: http://localhost:3001
    description: Local development server
security: []
paths:
  /api/v1/log/scan:
    get:
      summary: Scan entries
      description: |
        Scan log entries for a given key within an optional sequence range.

        Supports **long-polling**: set `follow=true` to hold the connection open
        until new data arrives or `timeout_ms` elapses (default 30 000 ms). This
        is useful for tailing a log stream in near-real-time.
      operationId: scan
      parameters:
        - name: key
          in: query
          required: true
          description: Key to scan (URL-encoded if it contains special characters).
          schema:
            type: string
        - name: start_seq
          in: query
          required: false
          description: Start sequence number (inclusive). Defaults to `0`.
          schema:
            type: integer
            format: uint64
            minimum: 0
        - name: end_seq
          in: query
          required: false
          description: End sequence number (exclusive). Defaults to `max uint64`.
          schema:
            type: integer
            format: uint64
            minimum: 0
        - name: limit
          in: query
          required: false
          description: Maximum number of entries to return.
          schema:
            type: integer
            minimum: 0
        - name: follow
          in: query
          required: false
          description: If `true`, long-poll until data is available or timeout.
          schema:
            type: boolean
        - name: timeout_ms
          in: query
          required: false
          description: Timeout in milliseconds for long-polling. Default `30000`.
          schema:
            type: integer
            format: uint64
            minimum: 0
      responses:
        '200':
          description: Scan results.
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/ScanResponse'
              example:
                status: success
                key: dGVzdC1rZXk=
                values:
                  - sequence: 42
                    value: dGVzdC12YWx1ZQ==
        '400':
          description: Invalid input (e.g. missing `key` parameter).
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/ErrorResponse'
        '500':
          description: Internal server error.
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/ErrorResponse'
components:
  schemas:
    ScanResponse:
      type: object
      description: Response containing scanned log entries for a key.
      properties:
        status:
          type: string
          example: success
        key:
          type: string
          format: byte
          description: The key that was scanned, base64-encoded.
        values:
          type: array
          items:
            $ref: '#/components/schemas/Value'
          description: Matching log entries.
      required:
        - status
        - values
    ErrorResponse:
      type: object
      description: Error response returned for all error cases.
      properties:
        status:
          type: string
          example: error
        message:
          type: string
          description: Human-readable error message.
      required:
        - status
        - message
    Value:
      type: object
      description: A single log entry returned by scan.
      properties:
        sequence:
          type: integer
          format: uint64
          description: Global sequence number of this entry.
        value:
          type: string
          format: byte
          description: Entry payload, base64-encoded.
      required:
        - sequence
        - value

````