Description
Validate each fields entry as a field-name token or star.
Web protocol data has several layers: a complete message or URL, individual fields or components, and the literal tokens within them. Delimiter presence, spelling, comparison rules, and parser normalization can affect results. A check of one component needs its stated scope before it can be used in a larger parser or policy decision.
Validate each fields entry as a field-name token or star.
When to use this tool
Use HTTP Vary Header Star Dominance when you need one stated URL, header, or protocol-component check in a diagnostic or parser workflow. Supply the input level specified below.
How to use the tool and how it works
- Enter fields. Keep parallel arrays aligned. Use the units and conventions below.
- Run the tool. Correct any format, range, or cross-field input error before interpreting the output.
- Read star, fields. Inspect star before interpreting the associated values.
Validate each fields entry as a field-name token or star. If any entry is star, return star true and fields containing only star; otherwise lowercase and deduplicate field names in first-occurrence order.1
| Input field | Meaning and units | Accepted input |
|---|---|---|
| fields | Fields | Required. Array of Text; maximum UTF-16 length 8192.; maximum items 256. |
| Output field | Interpretation | Returned shape |
|---|---|---|
| star | Star | Required. Boolean. |
| fields | Fields | Required. Array of Text; maximum UTF-16 length 8192.; maximum items 256. |
{
"input": {
"fields": [
"Accept",
"*",
"Origin"
]
},
"output": {
"star": true,
"fields": [
"*"
]
}
}Limitations and assumptions
- This accepts an already separated array, not a complete Vary header. It does not select a cache entry, compare request fields, or establish whether a response can be reused.
- The field tables state structural bounds; the mechanics also specify cross-field constraints. Malformed inputs and unsupported domains cause errors. A successful false flag, empty branch value, or zero placeholder has the meaning stated above and is distinct from an input error.
Alternative or Complementary methods
Use a complete URL or header parser when the task involves an entire field or message. Test actual browser, server, or cache behavior separately when a security or protocol decision depends on more than this component.
References
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