llama.cpp/examples/server/public/json-schema-to-grammar.mjs
Olivier Chafik 72114edf06
json-schema-to-grammar : fix order of props + non-str const/enum (#6232)
* json: ordered json in server/schema converter to respect orig order

* json: ws nits

* json: support non-string const / enums
2024-03-22 15:07:44 +02:00

539 lines
19 KiB
JavaScript

// WARNING: This file was ported from json-schema-to-grammar.py, please fix bugs / add features there first.
const SPACE_RULE = '" "?';
const PRIMITIVE_RULES = {
boolean: '("true" | "false") space',
number: '("-"? ([0-9] | [1-9] [0-9]*)) ("." [0-9]+)? ([eE] [-+]? [0-9]+)? space',
integer: '("-"? ([0-9] | [1-9] [0-9]*)) space',
value: 'object | array | string | number | boolean',
object: '"{" space ( string ":" space value ("," space string ":" space value)* )? "}" space',
array: '"[" space ( value ("," space value)* )? "]" space',
uuid: '"\\"" ' + [8, 4, 4, 4, 12].map(n => [...new Array(n)].map(_ => '[0-9a-fA-F]').join('')).join(' "-" ') + ' "\\"" space',
string: ` "\\"" (
[^"\\\\] |
"\\\\" (["\\\\/bfnrt] | "u" [0-9a-fA-F] [0-9a-fA-F] [0-9a-fA-F] [0-9a-fA-F])
)* "\\"" space`,
null: '"null" space',
};
const OBJECT_RULE_NAMES = ['object', 'array', 'string', 'number', 'boolean', 'null', 'value'];
// TODO: support "uri", "email" string formats
const DATE_RULES = {
'date' : '[0-9] [0-9] [0-9] [0-9] "-" ( "0" [1-9] | "1" [0-2] ) "-" ( \"0\" [1-9] | [1-2] [0-9] | "3" [0-1] )',
'time' : '([01] [0-9] | "2" [0-3]) ":" [0-5] [0-9] ":" [0-5] [0-9] ( "." [0-9] [0-9] [0-9] )? ( "Z" | ( "+" | "-" ) ( [01] [0-9] | "2" [0-3] ) ":" [0-5] [0-9] )',
'date-time': 'date "T" time',
'date-string': '"\\"" date "\\"" space',
'time-string': '"\\"" time "\\"" space',
'date-time-string': '"\\"" date-time "\\"" space',
};
const RESERVED_NAMES = {'root': true, ...PRIMITIVE_RULES, ...DATE_RULES};
const INVALID_RULE_CHARS_RE = /[^\dA-Za-z-]+/g;
const GRAMMAR_LITERAL_ESCAPE_RE = /[\n\r"]/g;
const GRAMMAR_RANGE_LITERAL_ESCAPE_RE = /[\n\r"\]\-\\]/g;
const GRAMMAR_LITERAL_ESCAPES = { '\r': '\\r', '\n': '\\n', '"': '\\"', '-': '\\-', ']': '\\]' };
const NON_LITERAL_SET = new Set('|.()[]{}*+?');
const ESCAPED_IN_REGEXPS_BUT_NOT_IN_LITERALS = new Set('[]()|{}*+?');
export class SchemaConverter {
constructor(options) {
this._propOrder = options.prop_order || {};
this._allowFetch = options.allow_fetch || false;
this._dotall = options.dotall || false;
this._rules = {'space': SPACE_RULE};
this._refs = {};
this._refsBeingResolved = new Set();
}
_formatLiteral(literal) {
const escaped = literal.replace(
GRAMMAR_LITERAL_ESCAPE_RE,
m => GRAMMAR_LITERAL_ESCAPES[m]
);
return `"${escaped}"`;
}
_formatRangeChar(literal) {
return JSON.stringify(literal).slice(1, -1).replace(
GRAMMAR_RANGE_LITERAL_ESCAPE_RE,
m => GRAMMAR_LITERAL_ESCAPES[m]
);
}
_addRule(name, rule) {
let escName = name.replace(INVALID_RULE_CHARS_RE, '-');
let key = escName;
if (escName in this._rules) {
if (this._rules[escName] === rule) {
return key;
}
let i = 0;
while ((`${escName}${i}` in this._rules) && (this._rules[`${escName}${i}`] !== rule)) {
i += 1;
}
key = `${escName}${i}`;
}
this._rules[key] = rule;
return key;
}
async resolveRefs(schema, url) {
const visit = async (n) => {
if (Array.isArray(n)) {
return Promise.all(n.map(visit));
} else if (typeof n === 'object' && n !== null) {
let ref = n.$ref;
let target;
if (ref !== undefined && !this._refs[ref]) {
if (ref.startsWith('https://')) {
if (!this._allowFetch) {
throw new Error('Fetching remote schemas is not allowed (use --allow-fetch for force)');
}
const fetch = (await import('node-fetch')).default;
const fragSplit = ref.split('#');
const baseUrl = fragSplit[0];
target = this._refs[baseUrl];
if (!target) {
target = await this.resolveRefs(await fetch(ref).then(res => res.json()), baseUrl);
this._refs[baseUrl] = target;
}
if (fragSplit.length === 1 || fragSplit[fragSplit.length - 1] === '') {
return target;
}
} else if (ref.startsWith('#/')) {
target = schema;
ref = `${url}${ref}`;
n.$ref = ref;
} else {
throw new Error(`Unsupported ref ${ref}`);
}
const selectors = ref.split('#')[1].split('/').slice(1);
for (const sel of selectors) {
if (!target || !(sel in target)) {
throw new Error(`Error resolving ref ${ref}: ${sel} not in ${JSON.stringify(target)}`);
}
target = target[sel];
}
this._refs[ref] = target;
} else {
await Promise.all(Object.values(n).map(visit));
}
}
return n;
};
return visit(schema);
}
_generateUnionRule(name, altSchemas) {
return altSchemas
.map((altSchema, i) => this.visit(altSchema, `${name ?? ''}${name ? '-' : 'alternative-'}${i}`))
.join(' | ');
}
_visitPattern(pattern, name) {
if (!pattern.startsWith('^') || !pattern.endsWith('$')) {
throw new Error('Pattern must start with "^" and end with "$"');
}
pattern = pattern.slice(1, -1);
const subRuleIds = {};
let i = 0;
const length = pattern.length;
const getDot = () => {
let rule;
if (this._dotall) {
rule = '[\\U00000000-\\U0010FFFF]';
} else {
// Accept any character... except \n and \r line break chars (\x0A and \xOD)
rule = '[\\U00000000-\\x09\\x0B\\x0C\\x0E-\\U0010FFFF]';
}
return this._addRule('dot', rule);
};
const toRule = ([s, isLiteral]) => isLiteral ? "\"" + s + "\"" : s;
const transform = () => {
const start = i;
// For each component of this sequence, store its string representation and whether it's a literal.
// We only need a flat structure here to apply repetition operators to the last item, and
// to merge literals at the and (we're parsing grouped ( sequences ) recursively and don't treat '|' specially
// (GBNF's syntax is luckily very close to regular expressions!)
const seq = [];
const joinSeq = () => {
const ret = [];
for (const [isLiteral, g] of groupBy(seq, x => x[1])) {
if (isLiteral) {
ret.push([[...g].map(x => x[0]).join(''), true]);
} else {
ret.push(...g);
}
}
if (ret.length === 1) {
return ret[0];
}
return [ret.map(x => toRule(x)).join(' '), false];
};
while (i < length) {
const c = pattern[i];
if (c === '.') {
seq.push([getDot(), false]);
i += 1;
} else if (c === '(') {
i += 1;
if (i < length) {
if (pattern[i] === '?') {
throw new Error(`Unsupported pattern syntax "${pattern[i]}" at index ${i} of /${pattern}/`);
}
}
seq.push([`(${toRule(transform())})`, false]);
} else if (c === ')') {
i += 1;
if (start <= 0 || pattern[start - 1] !== '(') {
throw new Error(`Unbalanced parentheses; start = ${start}, i = ${i}, pattern = ${pattern}`);
}
return joinSeq();
} else if (c === '[') {
let squareBrackets = c;
i += 1;
while (i < length && pattern[i] !== ']') {
if (pattern[i] === '\\') {
squareBrackets += pattern.slice(i, i + 2);
i += 2;
} else {
squareBrackets += pattern[i];
i += 1;
}
}
if (i >= length) {
throw new Error(`Unbalanced square brackets; start = ${start}, i = ${i}, pattern = ${pattern}`);
}
squareBrackets += ']';
i += 1;
seq.push([squareBrackets, false]);
} else if (c === '|') {
seq.push(['|', false]);
i += 1;
} else if (c === '*' || c === '+' || c === '?') {
seq[seq.length - 1] = [toRule(seq[seq.length - 1]) + c, false];
i += 1;
} else if (c === '{') {
let curlyBrackets = c;
i += 1;
while (i < length && pattern[i] !== '}') {
curlyBrackets += pattern[i];
i += 1;
}
if (i >= length) {
throw new Error(`Unbalanced curly brackets; start = ${start}, i = ${i}, pattern = ${pattern}`);
}
curlyBrackets += '}';
i += 1;
const nums = curlyBrackets.slice(1, -1).split(',').map(s => s.trim());
let minTimes, maxTimes;
if (nums.length === 1) {
minTimes = parseInt(nums[0], 10);
maxTimes = minTimes;
} else {
if (nums.length !== 2) {
throw new Error(`Invalid quantifier ${curlyBrackets}`);
}
minTimes = nums[0] ? parseInt(nums[0], 10) : 0;
maxTimes = nums[1] ? parseInt(nums[1], 10) : Infinity;
}
let [sub, subIsLiteral] = seq[seq.length - 1];
if (minTimes === 0 && maxTimes === Infinity) {
seq[seq.length - 1] = [`${sub}*`, false];
} else if (minTimes === 0 && maxTimes === 1) {
seq[seq.length - 1] = [`${sub}?`, false];
} else if (minTimes === 1 && maxTimes === Infinity) {
seq[seq.length - 1] = [`${sub}+`, false];
} else {
if (!subIsLiteral) {
let id = subRuleIds[sub];
if (id === undefined) {
id = this._addRule(`${name}-${Object.keys(subRuleIds).length + 1}`, sub);
subRuleIds[sub] = id;
}
sub = id;
}
const repeatedSub = Array.from({ length: minTimes }, () => subIsLiteral ? `"${sub.slice(1, -1).repeat(minTimes)}"` : sub);
const optionalSub = maxTimes !== undefined ? Array.from({ length: maxTimes - minTimes }, () => `${sub}?`) : [`${sub}*`];
seq[seq.length - 1] = [repeatedSub.concat(optionalSub).join(' '), false];
}
} else {
let literal = '';
while (i < length) {
if (pattern[i] === '\\' && i < length - 1) {
const next = pattern[i + 1];
if (ESCAPED_IN_REGEXPS_BUT_NOT_IN_LITERALS.has(next)) {
i += 1;
literal += pattern[i];
i += 1;
} else {
literal += pattern.slice(i, i + 2);
i += 2;
}
} else if (pattern[i] === '"') {
literal += '\\"';
i += 1;
} else if (!NON_LITERAL_SET.has(pattern[i]) &&
(i === length - 1 || literal === '' || pattern[i + 1] === '.' || !NON_LITERAL_SET.has(pattern[i+1]))) {
literal += pattern[i];
i += 1;
} else {
break;
}
}
if (literal !== '') {
seq.push([literal, true]);
}
}
}
return joinSeq();
};
return this._addRule(name, "\"\\\"\" " + toRule(transform()) + " \"\\\"\" space")
}
_resolveRef(ref) {
let refName = ref.split('/').pop();
if (!(refName in this._rules) && !this._refsBeingResolved.has(ref)) {
this._refsBeingResolved.add(ref);
const resolved = this._refs[ref];
refName = this.visit(resolved, refName);
this._refsBeingResolved.delete(ref);
}
return refName;
}
_generateConstantRule(value) {
return this._formatLiteral(JSON.stringify(value));
}
visit(schema, name) {
const schemaType = schema.type;
const schemaFormat = schema.format;
const ruleName = name in RESERVED_NAMES ? name + '-' : name == '' ? 'root' : name;
const ref = schema.$ref;
if (ref !== undefined) {
return this._addRule(ruleName, this._resolveRef(ref));
} else if (schema.oneOf || schema.anyOf) {
return this._addRule(ruleName, this._generateUnionRule(name, schema.oneOf || schema.anyOf));
} else if (Array.isArray(schemaType)) {
return this._addRule(ruleName, this._generateUnionRule(name, schemaType.map(t => ({ type: t }))));
} else if ('const' in schema) {
return this._addRule(ruleName, this._generateConstantRule(schema.const));
} else if ('enum' in schema) {
const rule = schema.enum.map(v => this._generateConstantRule(v)).join(' | ');
return this._addRule(ruleName, rule);
} else if ((schemaType === undefined || schemaType === 'object') &&
('properties' in schema ||
('additionalProperties' in schema && schema.additionalProperties !== true))) {
const required = new Set(schema.required || []);
const properties = Object.entries(schema.properties ?? {});
return this._addRule(ruleName, this._buildObjectRule(properties, required, name, schema.additionalProperties));
} else if ((schemaType === undefined || schemaType === 'object') && 'allOf' in schema) {
const required = new Set();
const properties = [];
const addComponent = (compSchema, isRequired) => {
const ref = compSchema.$ref;
if (ref !== undefined) {
compSchema = this._refs[ref];
}
if ('properties' in compSchema) {
for (const [propName, propSchema] of Object.entries(compSchema.properties)) {
properties.push([propName, propSchema]);
if (isRequired) {
required.add(propName);
}
}
}
};
for (const t of schema.allOf) {
if ('anyOf' in t) {
for (const tt of t.anyOf) {
addComponent(tt, false);
}
} else {
addComponent(t, true);
}
}
return this._addRule(ruleName, this._buildObjectRule(properties, required, name, /* additionalProperties= */ false));
} else if ((schemaType === undefined || schemaType === 'array') && ('items' in schema || 'prefixItems' in schema)) {
const items = schema.items ?? schema.prefixItems;
if (Array.isArray(items)) {
return this._addRule(
ruleName,
'"[" space ' +
items.map((item, i) => this.visit(item, `${name ?? ''}${name ? '-' : ''}tuple-${i}`)).join(' "," space ') +
' "]" space'
);
} else {
const itemRuleName = this.visit(items, `${name ?? ''}${name ? '-' : ''}item`);
const listItemOperator = `( "," space ${itemRuleName} )`;
let successiveItems = '';
let minItems = schema.minItems || 0;
const maxItems = schema.maxItems;
if (minItems > 0) {
successiveItems = listItemOperator.repeat(minItems - 1);
minItems--;
}
if (maxItems !== undefined && maxItems > minItems) {
successiveItems += `${listItemOperator}?`.repeat(maxItems - minItems - 1);
} else {
successiveItems += `${listItemOperator}*`;
}
const rule = minItems === 0
? `"[" space ( ${itemRuleName} ${successiveItems} )? "]" space`
: `"[" space ${itemRuleName} ${successiveItems} "]" space`;
return this._addRule(ruleName, rule);
}
} else if ((schemaType === undefined || schemaType === 'string') && 'pattern' in schema) {
return this._visitPattern(schema.pattern, ruleName);
} else if ((schemaType === undefined || schemaType === 'string') && /^uuid[1-5]?$/.test(schema.format || '')) {
return this._addRule(
ruleName === 'root' ? 'root' : schemaFormat,
PRIMITIVE_RULES['uuid'])
} else if ((schemaType === undefined || schemaType === 'string') && schema.format in DATE_RULES) {
for (const [t, r] of Object.entries(DATE_RULES)) {
this._addRule(t, r);
}
return schemaFormat + '-string';
} else if ((schemaType === 'object') || (Object.keys(schema).length === 0)) {
for (const n of OBJECT_RULE_NAMES) {
this._addRule(n, PRIMITIVE_RULES[n]);
}
return this._addRule(ruleName, 'object');
} else {
if (!(schemaType in PRIMITIVE_RULES)) {
throw new Error(`Unrecognized schema: ${JSON.stringify(schema)}`);
}
// TODO: support minimum, maximum, exclusiveMinimum, exclusiveMaximum at least for zero
return this._addRule(ruleName === 'root' ? 'root' : schemaType, PRIMITIVE_RULES[schemaType]);
}
}
_buildObjectRule(properties, required, name, additionalProperties) {
const propOrder = this._propOrder;
// sort by position in prop_order (if specified) then by original order
const sortedProps = properties.map(([k]) => k).sort((a, b) => {
const orderA = propOrder[a] || Infinity;
const orderB = propOrder[b] || Infinity;
return orderA - orderB || properties.findIndex(([k]) => k === a) - properties.findIndex(([k]) => k === b);
});
const propKvRuleNames = {};
for (const [propName, propSchema] of properties) {
const propRuleName = this.visit(propSchema, `${name ?? ''}${name ? '-' : ''}${propName}`);
propKvRuleNames[propName] = this._addRule(
`${name ?? ''}${name ? '-' : ''}${propName}-kv`,
`${this._formatLiteral(JSON.stringify(propName))} space ":" space ${propRuleName}`
);
}
const requiredProps = sortedProps.filter(k => required.has(k));
const optionalProps = sortedProps.filter(k => !required.has(k));
if (typeof additionalProperties === 'object' || additionalProperties === true) {
const subName = `${name ?? ''}${name ? '-' : ''}additional`;
const valueRule = this.visit(additionalProperties === true ? {} : additionalProperties, `${subName}-value`);
propKvRuleNames['*'] = this._addRule(
`${subName}-kv`,
`${this._addRule('string', PRIMITIVE_RULES['string'])} ":" space ${valueRule}`);
optionalProps.push('*');
}
let rule = '"{" space ';
rule += requiredProps.map(k => propKvRuleNames[k]).join(' "," space ');
if (optionalProps.length > 0) {
rule += ' (';
if (requiredProps.length > 0) {
rule += ' "," space ( ';
}
const getRecursiveRefs = (ks, firstIsOptional) => {
const [k, ...rest] = ks;
const kvRuleName = propKvRuleNames[k];
let res;
if (k === '*') {
res = this._addRule(
`${name ?? ''}${name ? '-' : ''}additional-kvs`,
`${kvRuleName} ( "," space ` + kvRuleName + ` )*`
)
} else if (firstIsOptional) {
res = `( "," space ${kvRuleName} )?`;
} else {
res = kvRuleName;
}
if (rest.length > 0) {
res += ' ' + this._addRule(
`${name ?? ''}${name ? '-' : ''}${k}-rest`,
getRecursiveRefs(rest, true)
);
}
return res;
};
rule += optionalProps.map((_, i) => getRecursiveRefs(optionalProps.slice(i), false)).join(' | ');
if (requiredProps.length > 0) {
rule += ' )';
}
rule += ' )?';
}
rule += ' "}" space';
return rule;
}
formatGrammar() {
let grammar = '';
for (const [name, rule] of Object.entries(this._rules).sort(([a], [b]) => a.localeCompare(b))) {
grammar += `${name} ::= ${rule}\n`;
}
return grammar;
}
}
// Helper function to group elements by a key function
function* groupBy(iterable, keyFn) {
let lastKey = null;
let group = [];
for (const element of iterable) {
const key = keyFn(element);
if (lastKey !== null && key !== lastKey) {
yield [lastKey, group];
group = [];
}
group.push(element);
lastKey = key;
}
if (group.length > 0) {
yield [lastKey, group];
}
}