Truncate

The Truncate function limits string fields to a specified length in bytes or characters.

Usage

• Operates On: Field values
• Supported Field Types: string
• Mode: Specific Field | Target Map | Matching
• Label: Optional
• Filter: Optional

Specific Fields Mode - Required Configuration

• Specific Fields: A comma separated list of fields to truncate
• Limit: The max length for the field
• Limit Type: Bytes | Characters

Target Map Mode - Required Configuration

• Target Map: The name of field to truncate children string fields. Must be of type map
• Limit: The max length for the field
• Limit Type: Bytes | Characters

Optional Configuration

• Excluded Fields: A comma separated list of field names to not apply truncation to.

Matching Mode - Required Configuration

• Target Map: The name of field to truncate children string fields. Must be of type map
• Limit: The max length for the field
• Limit Type: Bytes | Characters
• Matching Expression: The matching expression to select field names or values to trigger truncation. Supports wildcard matches or a regular expression. Regular expressions should be wrapped in //.
• Expression Match On: Field Name | Field Value | Field Name or Value

Example - Specific Fields

Truncate the stack_trace field to 128 bytes in order to strip the lower stack trace frames.

Configuration

• Mode: Specific Fields
• Specific Fields: example.stack_trace
• Limit: 128
• Limit Type: bytes

Before

{
  "example" : {
    "stack_trace": "goroutine 91 [IO wait]:\ninternal/poll.runtime_pollWait(0x7fa0acc67790, 0x72)\n/usr/local/go/src/runtime/netpoll.go:343 +0x85\ninternal/poll.(*pollDesc).wait(0xc000946000?, 0xc000b3a000?, 0x0)\n/usr/local/go/src/internal/poll/fd_poll_runtime.go:84 +0x27\ninternal/poll.(*pollDesc).waitRead(...)\n/usr/local/go/src/internal/poll/fd_poll_runtime.go:89\ninternal/poll.(*FD).Read(0xc000946000, {0xc000b3a000, 0x8000, 0x8000})\n/usr/local/go/src/internal/poll/fd_unix.go:164 +0x27a\nnet.(*netFD).Read(0xc000946000, {0xc000b3a000?, 0x10?, 0xc000ab0e38?})\n/usr/local/go/src/net/fd_posix.go:55 +0x25"
  }
}

After

{
  "example" : {
    "stack_trace": "goroutine 91 [IO wait]:\ninternal/poll.runtime_pollWait(0x7fa0acc67790, 0x72)\n/usr/local/go/src/runtime/netpoll.go:343 +0x85\ninte"
  }
}

Example - Target Map

Trim all field values in log.errors to a 10 character maximum length, except for the message field.

Configuration

• Mode: Target Map
• Target Map: log.errors
• Limit: 10
• Limit Type: characters
• Excluded Fields: message

Before

{
  "log" : {
    "errors": {
      "stack": "(RuntimeError)\n\tfrom /home/mheffner/git/streamfold/banjo-store/.bundle/gems/ruby",
      "location": "/home/mheffner/git/streamfold/banjo-store/.bundle/gems/ruby",
      "message": "NameError: undefined local variable or method 'intro'"
    }
  }
}

After

{
  "log" : {
    "errors": {
      "stack": "(RuntimeEr",
      "location": "/home/mhef",
      "message": "NameError: undefined local variable or method 'intro'"
    }
  }
}

Example - Matching

Truncate all fields matching error* in the log map to 10 characters.

Configuration

• Mode: Matching
• Target Map: log
• Limit: 10
• Limit Type: characters
• Matching Expression: Field Name: error*

Before

{
  "log" : {
    "error": "Can not connect to MySQL",
    "error.verbose": "(RuntimeError)\n\tfrom /home/mheffner/git/streamfold/banjo-store/: Can not connect to MySQL",
    "msg": "Error connecting to database"
  }
}

After

{
  "log" : {
    "error": "Can not co",
    "error.verbose": "(RuntimeEr",
    "msg": "Error connecting to database"
  }
}