ballerina/io package

Primitives Summary

Type Description

Type Definitions

Type Values Description
Format tdf | default | csv
Mode w | rw | r | a
Seperator : | , |

Annotations

Name Attachement Points Data Type Description

Objects Summary

Object Description
SocketProperties
SocketProperties structs represents the properties which are used to configure TCP connection.

Endpoints Summary

Endpoint Description

Functions Summary

Return Type Function and Description
CSVChannel | error openCsvFile(string path)
Function to create CSV channel to read CSV input
ByteChannel openFile(string path, Mode accessMode)
Opens a byte channel from a specified file location
Socket | error openSecureSocket(string host, int port, SocketProperties options)
Open a secure socket connection with a remote server
Socket | error openSocket(string host, int port, SocketProperties options)
Opens a socket from a specified network location
print()
Prints a 'any' value to the STDOUT
println()
Prints an any value to the STDOUT in a new line
string readln(any a)
Returns the input read from STDIN
string sprintf(string format)
Returns a formatted string using the specified format string and arguments

Global Variables

Name Data Type Description
APPEND Mode Describes access mode for append
COLON Seperator Describes TDF format to open CSV
COMMA Seperator Supported record formats of CSV
READ Mode Permissions which will be used to open file
RW Mode Describes acces mode for reading and writing
TAB Seperator Describes RFC4180 format to open CSV
WRITE Mode Describes access mode for writing

public object SocketProperties

SocketProperties structs represents the properties which are used to configure TCP connection.

Field Name Data Type Default Value Description
localPort int
keyStoreFile string
keyStorePassword string
trustStoreFile string
trustStorePassword string
certPassword string
sslEnabledProtocols string
ciphers string
sslProtocol string

public function openCsvFile(string path) returns (CSVChannel | error)

Function to create CSV channel to read CSV input

Parameter Name Data Type Default Value Description
path string Specfies the path to the CSV file
Return Type Description
CSVChannel | error DelimitedRecordChannel converted from CSV Channel

public function openFile(string path, Mode accessMode) returns (ByteChannel)

Opens a byte channel from a specified file location

Parameter Name Data Type Default Value Description
path string path to the file location
accessMode Mode whether the file should be opened for read,write or append
Return Type Description
ByteChannel Channel which will allow to source/sink

public function openSecureSocket(string host, int port, SocketProperties options) returns (Socket | error)

Open a secure socket connection with a remote server

Parameter Name Data Type Default Value Description
host string Remote server domain/IP
port int Remote server port
options SocketProperties Connection stream that bridge the client and the server
Return Type Description
Socket | error Socket which will allow to communicate with a remote server

public function openSocket(string host, int port, SocketProperties options) returns (Socket | error)

Opens a socket from a specified network location

Parameter Name Data Type Default Value Description
host string Remote server domain/IP
port int Remote server port
options SocketProperties Connection stream that bridge the client and the server
Return Type Description
Socket | error Socket which will allow to communicate with a remote server

public function print()

Prints a 'any' value to the STDOUT

public function println()

Prints an any value to the STDOUT in a new line

public function readln(any a) returns (string)

Returns the input read from STDIN

Parameter Name Data Type Default Value Description
a any any value to be printed
Return Type Description
string

public function sprintf(string format) returns (string)

Returns a formatted string using the specified format string and arguments

Parameter Name Data Type Default Value Description
format string Format specifier
Return Type Description
string Formatted string

public type ByteChannel object

Ballerina ByteChannel represents a channel which will allow I/O operations to be done

  • <ByteChannel> read(int nBytes) returns ((blob,int) | error)

    Function to read bytes

    Parameter Name Data Type Default Value Description
    nBytes int Number of bytes which should be read
    Return Type Description
    (blob,int) | error The bytes which were read
  • <ByteChannel> write(blob content, int offset) returns (int | error)

    Function to write bytes

    Parameter Name Data Type Default Value Description
    content blob Bytes which should be written
    offset int If the bytes need to be written with an offset, the value of that offset
    Return Type Description
    int | error Number of bytes written
  • <ByteChannel> close() returns (error)

    Function to close a byte channel

    Return Type Description
    error Returns if there's any error while performaing I/O operation
  • <ByteChannel> base64Encode() returns (ByteChannel | error)

    Encode a given ByteChannel with Base64 encoding scheme.

    Return Type Description
    ByteChannel | error Return an encoded ByteChannel
  • <ByteChannel> base64Decode() returns (ByteChannel | error)

    Decode a given ByteChannel with Base64 encoding scheme.

    Return Type Description
    ByteChannel | error Return a decoded ByteChannel

public type CSVChannel object

Ballerina DelimitedRecordChannel represents a channel which will allow to read/write text records

Field Name Data Type Default Value Description
dc DelimitedTextRecordChannel
  • <CSVChannel> hasNext() returns (boolean)

    Function to check whether next record is available or not

    Return Type Description
    boolean True if the channel has more records; false otherwise
  • <CSVChannel> getNext() returns (string[] | error)

    Function to read text records

    Return Type Description
    string[] | error Fields listed in the record
  • <CSVChannel> write(string[] record) returns (error)

    Function to write text records

    Parameter Name Data Type Default Value Description
    record string[]
    Return Type Description
    error Returns if there's any error while performaing I/O operation
  • <CSVChannel> close() returns (error)

    Function to close the text record channel

    Return Type Description
    error Returns if there's any error while performaing I/O operation
  • <CSVChannel> getTable(typedesc structType) returns (table | error)

    Function to load delimited records to in-memory table

    Parameter Name Data Type Default Value Description
    structType typedesc Name of the struct that each record need to populate
    Return Type Description
    table | error Returns if there's any error while performaing I/O operation

public type CharacterChannel object

Ballerina CharacterChannel represents a channel which will allow to read/write characters

  • <CharacterChannel> read(int numberOfChars) returns (string | error)

    Function to read characters

    Parameter Name Data Type Default Value Description
    numberOfChars int Number of characters which should be read
    Return Type Description
    string | error The character sequence which was read
  • <CharacterChannel> write(string content, int startOffset) returns (int | error)

    Function to write characters

    Parameter Name Data Type Default Value Description
    content string Text content which should be written
    startOffset int If the content needs to be written with an offset, the value of that offset
    Return Type Description
    int | error Number of characters written
  • <CharacterChannel> readJson() returns (json | error)

    Function to convert a character channel to a JSON

    Return Type Description
    json | error Returns A JSON
  • <CharacterChannel> readXml() returns (xml | error)

    Function to convert a character channel to a XML

    Return Type Description
    xml | error Returns A XML
  • <CharacterChannel> writeJson(json content) returns (error)

    Writes json through a given character channel

    Parameter Name Data Type Default Value Description
    content json
    Return Type Description
    error
  • <CharacterChannel> writeXml(xml content) returns (error)

    Writes xml through a given character channel

    Parameter Name Data Type Default Value Description
    content xml
    Return Type Description
    error
  • <CharacterChannel> close() returns (error)

    Function to close a character channel

    Return Type Description
    error Returns if there's any error while performaing I/O operation

public type DelimitedTextRecordChannel object

Ballerina DelimitedRecordChannel represents a channel which will allow to read/write text records

  • <DelimitedTextRecordChannel> hasNext() returns (boolean)

    Function to check whether next record is available or not

    Return Type Description
    boolean True if the channel has more records; false otherwise
  • <DelimitedTextRecordChannel> getNext() returns (string[] | error)

    Function to read text records

    Return Type Description
    string[] | error Fields listed in the record
  • <DelimitedTextRecordChannel> write(string[] record) returns (error)

    Function to write text records

    Parameter Name Data Type Default Value Description
    record string[]
    Return Type Description
    error Returns if there's any error while performaing I/O operation
  • <DelimitedTextRecordChannel> close() returns (error)

    Function to close the text record channel

    Return Type Description
    error Returns if there's any error while performaing I/O operation

public type Socket object

Represetns a TCP socket.

Field Name Data Type Default Value Description
channel ByteChannel
port int
localPort int
address string
localAddress string
  • <Socket> close() returns (error)

    Close the socket connection with the remote server

    Return Type Description
    error Returns an error if socket could not be closed
  • <Socket> shutdownInput() returns (error)

    Shutdown the connection for reading

    Return Type Description
    error Returns an error if socket could not be shutdown for reading
  • <Socket> shutdownOutput() returns (error)

    Shutdown the connection for writing

    Return Type Description
    error Returns an error if socket could not be shutdown for writing