Description
Construct single byte ranges, resolve inclusive intervals against a supplied resource length, and label exact overlap and disjoint pairs.
A protocol fixture is local test data representing headers, messages, identifiers, or request decisions. Serialization and parsing can be checked without contacting a server, while authentication, delivery, and actual client behavior require separate tests.
Construct single byte ranges, resolve inclusive intervals against a supplied resource length, and label exact overlap and disjoint pairs.
When to use this tool
Use this generator to create reproducible http range overlap dataset cases from the supplied model or bank. Inspect the returned evidence before using cases in a test or exercise.
How to use the tool and how it works
- Supply resourceLength, forms, requestCount in the field shapes below. Set seed when you need an explicit replay.
- Run the tool and correct any input error. For generated controls, distinguish a successful fixture containing an invalid case from failure to generate the fixture.
- Read ranges, overlaps, disjointPairs. Use the conventions below and keep answer-bearing fields separate when presenting an exercise.
Generate single closed, open-ended, or suffix byte ranges and delegate lexical parsing. Resolve them against resourceLength with inclusive ends, then compare every satisfiable pair for inclusive overlap or disjointness.1
Delegated operations used for this result: range parser. Their calculation or parsing conventions apply to the corresponding result fields.2
| Input field | Meaning and units | Accepted input |
|---|---|---|
| resourceLength | Resource Length | Required. Safe integer; minimum 0. |
| forms | Forms | Required. Array of Text; one of "closed", "open", "suffix".; minimum items 1; maximum items 3. |
| requestCount | Request Count | Required. Safe integer; minimum 2; maximum 16. |
| seed | Optional numeric seed; takes precedence over context randomness. Without either, use the fixed tool.io default seed. | Optional. Safe integer. |
| Output field | Interpretation | Returned shape |
|---|---|---|
| ranges | Ranges | Required. Array of Object; no unknown keys.; minimum items 2; maximum items 16. |
| ranges[].header | Header | Required. Text; maximum UTF-16 length 65536. |
| ranges[].kind | Kind | Required. Text; maximum UTF-16 length 65536. |
| ranges[].satisfiable | Satisfiable | Required. Boolean. |
| ranges[].start | Start | Required. Safe integer. or Null. |
| ranges[].end | End | Required. Safe integer. or Null. |
| overlaps | Overlaps | Required. Array of Object; no unknown keys.; minimum items 0; maximum items 120. |
| overlaps[].left | Left | Required. Safe integer. |
| overlaps[].right | Right | Required. Safe integer. |
| overlaps[].start | Start | Required. Safe integer. |
| overlaps[].end | End | Required. Safe integer. |
| disjointPairs | Disjoint Pairs | Required. Array of Array of Safe integer.; minimum items 2; maximum items 2.; minimum items 0; maximum items 120. |
| randomness | Replay metadata: source is seed or context; seed is the normalized 32-bit seed or null for a context source. | Required. Object; no unknown keys. |
| randomness.seed | Optional numeric replay seed; normalization and precedence are explained below. | Required. Safe integer. or Null. |
| randomness.source | Source | Required. Text; one of "context", "seed". |
An explicit safe-integer seed takes precedence over injected context randomness and is normalized to an unsigned 32-bit integer. With no seed and no context source, replay uses the fixed tool.io default seed. A context source must return finite values from zero inclusive to one exclusive; its advancing state must be retained separately. randomness records the source and normalized seed, or null for context. These generators are not cryptographic random sources.
{
"input": {
"resourceLength": 10,
"forms": [
"closed"
],
"requestCount": 2,
"seed": 42
},
"output": {
"ranges": [
{
"header": "bytes=4-11",
"kind": "closed",
"satisfiable": true,
"start": 4,
"end": 9
},
{
"header": "bytes=1-7",
"kind": "closed",
"satisfiable": true,
"start": 1,
"end": 7
}
],
"overlaps": [
{
"left": 0,
"right": 1,
"start": 4,
"end": 7
}
],
"disjointPairs": [],
"randomness": {
"seed": 42,
"source": "seed"
}
}
}Limitations and assumptions
- Unsatisfiable ranges have null start and end and are excluded from pair comparisons. A zero-length suffix is unsatisfiable. This does not issue requests, generate multipart responses, or model all Range header forms.
- A replay requires the same complete input and implementation. Randomized construction does not guarantee uniform coverage of every feasible output; finite samples can repeat unless a distinct-selection rule is explicitly stated.
- The field tables state structural bounds; cross-field constraints and bounded search or output budgets also apply. Unknown keys are rejected where the object contract disallows them. Input errors are distinct from null fields and deliberate invalid controls in a successful output.
Alternative or Complementary methods
For a supplied example, inspect the returned construction or delegated check directly. To evaluate a consumer, also test cases chosen for its own boundaries; a generated finite corpus does not establish exhaustive coverage.
References
Similar or alternative tools
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