Logger

Logger

The Logger control interface is used to create file logs into the log folder of the current storage volume.

The following API is asynchronous and using Promise.
To use this API, you first need to get the logger control interface thanks to IDAL.getControlInterfaces().

Methods

delete(id) → {Promise.<boolean>|Promise.<ErrorStatus>}

Delete a log file.

Parameters:
Name Type Description
id string

The identifier of the log file to delete (basically: a filename).
Returns:

  • A promise resolved with a boolean value.

    Type
    Promise.<boolean>

  • A promise rejected with an ErrorStatus.

    Type
    Promise.<ErrorStatus>

list() → {Promise.<Array.<string>>|Promise.<ErrorStatus>}

Get the list of existing log identifiers.

Returns:

  • A promise resolved with an array of strings, each element being a log identifier.

    Type
    Promise.<Array.<string>>

  • A promise rejected with an ErrorStatus.

    Type
    Promise.<ErrorStatus>

log(id, message) → {Promise.<boolean>|Promise.<ErrorStatus>}

Log a message into a given log file.

The message is stored in a file on the current storage media into the log folder.

Parameters:
Name Type Description
id string

The identifier of the log file (basically: a filename).
message string

The message to write into the file.
Returns:

  • A promise resolved with a boolean value.

    Type
    Promise.<boolean>

  • A promise rejected with an ErrorStatus.

    Type
    Promise.<ErrorStatus>

read(id, offset, length) → {Promise.<Logger~ReadInfo>|Promise.<ErrorStatus>}

Read the content of a log.

You can use this method to retrieve the content of the log, for example if you need to push them to a remote server.
The returned data are Base64 encoded (and not raw strings) to avoid issues when the data are encoding multibyte characters.
When there are no more data to read, this call will return a ReadInfo with a zero length.

Parameters:
Name Type Description
id string

The identifier of the log file to read.
offset number

The read offset.
length number

The maximum number of bytes that can be read.
It is possible to read at most of 1 MB (1048576 bytes) of data at a time.
Returns:

stat(id) → {Promise.<Logger~StatInfo>|Promise.<ErrorStatus>}

Get the status of a log (size).

Parameters:
Name Type Description
id string

The identifier of the log file to query for status.
Returns:

Type Definitions

ReadInfo

A ReadInfo Contains the result of a call to Logger.read().

Properties:
Name Type Description
data string

Is a Base64 string encoding the data read from a log file.
length number

Is the number of bytes that have been read. Beware, this is not the length of data but the number of bytes that have been used to encode the data string.

StatInfo

A StatInfo Contains the result of a call to Logger.stat().

Properties:
Name Type Description
size number

Is the size (number of bytes) of the log file.