flowground/csv-component

CSV Reading and Writing component for elastic.io platform

CSV Component

Table of Contents

• Description
• How works
• Requirements
• Environment variables
• Credentials
• Actions
  • Read CSV attachment
  • Create CSV From Message Stream
  • Create CSV From JSON Array
• Limitations

Description

A component to read and write Comma Separated Values (CSV) files.

How works

The component can read the CSV file from a remote URL or from the message attachment. It can also write a CSV file from the incoming events.

Requirements

Environment variables

Name	Mandatory	Description	Values
EIO_REQUIRED_RAM_MB	false	Value of allocated memory to component	Recommended: 512/1024
REQUEST_TIMEOUT	false	HTTP request timeout in milliseconds	Default value: 10000
REQUEST_RETRY_DELAY	false	Delay between retry attempts in milliseconds	Default value: 7000
REQUEST_MAX_RETRY	false	Number of HTTP request retry attempts	Default value: 7
REQUEST_MAX_CONTENT_LENGTH	false	Max size of http request in bytes	Default value: 10485760
TIMEOUT_BETWEEN_EVENTS	false	Number of milliseconds write action wait before creating separate attachments	Default value: 10000

Credentials

The component does not require credentials to function.

Actions

Read CSV attachment

This action will read the CSV attachment of the incoming message or from the specified URL and output a JSON object. To configure this action the following fields can be used:

Config Fields

• Emit Behavior - this selector configures output behavior of the component. If the option is Fetch All - the component emits an array of messages, otherwise (Emit Individually) - the component emits a message per row.

Input Metadata

• URL - We will fetch this URL and parse it as CSV file
• Contains headers - if true, the first row of parsed data will be interpreted as field names, false by default.
• Delimiter - The delimiting character. Leave blank to auto-detect from a list of most common delimiters.
• Convert Data types - numeric, date and boolean data will be converted to their type instead of remaining strings, false by default.

Create CSV From Message Stream

This action will combine multiple incoming events into a CSV file until there is a gap of more than 10 seconds between events. Afterwards, the CSV file will be closed and attached to the outgoing message.

Config Fields

• Upload CSV as file to attachments - If checked store the generated CSV data as an attachment. If unchecked, place the CSV as a string in the outbound message.
• Separator - A single char used to delimit the CSV file. Default to ,
• Column Order - A string delimited with the separator indicating which columns & in what order the columns should appear in the resulting file. If omitted, the column order in the resulting file will not be deterministic. Columns names will be trimmed (removed spaces in beginning and end of column name, for example: 'col 1,col 2 ,col 3, col 4' => ['col 1', 'col 2', 'col 3', 'col 4'])

Input Metadata

• Include Headers - Indicates if a header row should be included in the generated file.
• Input Object - Object to be written as a row in the CSV file. If the Column Order is specified, then individual properties can be specified.

Output Metadata

• If Upload CSV as file to attachments is checked:

  • csvString - The output CSV as a string inline in the body

• If Upload CSV as file to attachments is not checked:

  • attachmentUrl - A URL to the CSV output
  • type - Always set to .csv
  • size - Size in bytes of the resulting CSV file
  • attachmentCreationTime - When the attachment was generated
  • attachmentExpiryTime - When the attachment is set to expire
  • contentType - Always set to text/csv

Create CSV From JSON Array

This action will convert an incoming array into a CSV file

Config Fields

• Upload CSV as file to attachments - If checked store the generated CSV data as an attachment. If unchecked, place the CSV as a string in the outbound message.
• Separator - A single char used to delimit the CSV file. Default to ,
• Column Order - A string delimited with the separator indicating which columns & in what order the columns should appear in the resulting file. If omitted, the column order in the resulting file will not be deterministic.

Input Metadata

• Include Headers - Indicates if a header row should be included in the generated file.
• Input Array - Array of objects to be written as rows in the CSV file. (One row per object + headers) If the Column Order is specified, then individual properties can be specified. The component will throw an error when the array is empty.

Output Metadata

• If Upload CSV as file to attachments is checked:

  • csvString - The output CSV as a string inline in the body

• If Upload CSV as file to attachments is not checked:

  • attachmentUrl - A URL to the CSV output
  • type - Always set to .csv
  • size - Size in bytes of the resulting CSV file
  • attachmentCreationTime - When the attachment was generated
  • attachmentExpiryTime - When the attachment is set to expire
  • contentType - Always set to text/csv

Limitations

General

• You may get Component run out of memory and terminated. error during run-time, that means that component needs more memory, please add EIO_REQUIRED_RAM_MB environment variable with an appropriate value (e.g. value 1024 means that 1024 MB will be allocated) for the component in this case.
• Maximal possible size for an attachment is 10 MB.
• Attachments mechanism does not work with Local Agent Installation
• Inbound message in Message Stream and each element of JSON Array should be a plain Object, if value not a primitive type it will be set as [object Object]