DNS TXT String Wire Formatter
Format a nonempty DNS TXT character-string list as length-prefixed octets without a terminator; total output is bounded to 128 bytes and strings are not text-decoded.
Description
Format a nonempty DNS TXT character-string list as length-prefixed octets without a terminator; total output is bounded to 128 bytes and strings are not text-decoded.
Formatting TXT components requires retaining their boundaries, including empty strings. Each supplied byte array gets a one-byte length prefix.
When to use this tool
Format a nonempty DNS TXT character-string list as length-prefixed octets without a terminator; total output is bounded to 128 bytes and strings are not text-decoded.
- Prepare the supplied stringsJson fields for this operation.
- Compare the complete example with the representation used by your own input before carrying the result into another step.
How to use the tool and how it works
- Enter stringsJson. Use the exact text syntax, units and index conventions explained below.
- Run the tool. If input validation fails, correct the supplied fields before interpreting any result.
- Read result.bytes. Interpret false, null and empty lists using the distinctions below; they can be valid outputs.
Parse stringsJson as a nonempty JSON array of byte arrays. Flatten each component as its length followed by its bytes, and reject a total encoded size above 128 bytes.1
| Input field | Meaning and representation | Accepted input |
|---|---|---|
| stringsJson | JSON text, entered as one text field. The decoded structure is illustrated below; it is not a separate file. | Text |
For the JSON text fields, the following decoded structures show the example records before they are serialized into input strings. Keep field names, list nesting and value types as shown.
[
{
"field": "stringsJson",
"decoded": [
[
1,
2
],
[],
[
3
]
]
}
]| Output field | Interpretation |
|---|---|
| result | Object containing the named outputs below. |
| result.bytes | The bytes list in the ordering and representation described above. |
{
"input": {
"stringsJson": "[[1,2],[],[3]]"
},
"output": {
"result": {
"bytes": [
2,
1,
2,
0,
1,
3
]
}
}
}Limitations and assumptions
- The local byte-array limit also bounds each component to 128 bytes. No text encoding, DNS packet header or application-specific TXT content is generated.
- All declared input fields are required and unexpected top-level fields are rejected. Numbers must be finite; lists are limited to 128 entries and ordinary text fields to 8,192 UTF-16 code units, with tighter limits where stated.
- JSON text inputs must parse within bounded nesting and size limits. Numeric outputs outside the safe finite range are rejected; large exact integer results use decimal strings. Indexes and half-open spans are zero-based unless a rank is explicitly described as one-based.
Alternative or Complementary methods
Use a packet-aware DNS parser or resolver when the task requires compression-chain validation, live records or complete resource-record semantics. Keep byte labels, presentation text and network packets distinct.
References
Similar or alternative tools
- DNS Label List Wire Formatter
Format uncompressed DNS wire labels from explicit octets with 63-byte label and 255-byte protocol whole-name bounds, plus a 128-byte local output budget; appends root zero, no compression or IDNA.
- DNS TXT String Wire Parser
Parse a complete nonempty DNS TXT wire character-string list, retaining empty strings and rejecting incomplete trailing payload; no text encoding assumptions.