Files
genieacs/lib/common/expression.ts
T
2020-07-29 02:31:31 -07:00

326 lines
9.2 KiB
TypeScript

/**
* Copyright 2013-2019 GenieACS Inc.
*
* This file is part of GenieACS.
*
* GenieACS is free software: you can redistribute it and/or modify
* it under the terms of the GNU Affero General Public License as
* published by the Free Software Foundation, either version 3 of the
* License, or (at your option) any later version.
*
* GenieACS is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU Affero General Public License for more details.
*
* You should have received a copy of the GNU Affero General Public License
* along with GenieACS. If not, see <http://www.gnu.org/licenses/>.
*/
import { map, mapAsync, parseLikePattern } from "./expression-parser";
import { Expression } from "../types";
const isArray = Array.isArray;
const regExpCache = new WeakMap<any, RegExp>();
const REDUCE_SKIP = {};
function reduce(exp, callback): Expression {
let loop = true;
while (loop) {
loop = false;
for (let i = 2; i < exp.length; ++i) {
const res = callback(exp[i - 1], exp[i], i - 2);
if (res !== REDUCE_SKIP) {
loop = true;
exp = exp.slice();
exp.splice(i - 1, 2, res);
}
}
}
if (exp.length === 2) return exp[1];
return exp;
}
export function likePatternToRegExp(pat: string, esc = "", flags = ""): RegExp {
const convChars = {
"-": "\\-",
"/": "\\/",
"\\": "\\/",
"^": "\\^",
$: "\\$",
"*": "\\*",
"+": "\\+",
"?": "\\?",
".": "\\.",
"(": "\\(",
")": "\\)",
"|": "\\|",
"[": "\\[",
"]": "\\]",
"{": "\\{",
"}": "\\}",
"\\%": ".*",
"\\_": ".",
};
let chars = parseLikePattern(pat, esc);
if (!chars.length) return new RegExp("^$", flags);
chars = chars.map((c) => convChars[c] || c);
chars[0] = chars[0] === ".*" ? "" : "^" + chars[0];
const l = chars.length - 1;
chars[l] = [".*", ""].includes(chars[l]) ? "" : chars[l] + "$";
return new RegExp(chars.join(""), flags);
}
function evalExp(e: Expression): Expression {
if (e[0] === "AND") {
return reduce(e, (a, b) => {
if (!isArray(a)) return a ? b : a;
if (!isArray(b)) return b ? a : b;
return REDUCE_SKIP;
});
} else if (e[0] === "OR") {
return reduce(e, (a, b) => {
if (!isArray(a)) return a ? a : b;
if (!isArray(b)) return b ? b : a;
return REDUCE_SKIP;
});
} else if (e[0] === "NOT") {
if (!isArray(e[1])) return !e[1];
else if (e[1][0] === "NOT") return e[1][1];
} else if (e[0] === "IS NULL") {
if (isArray(e[1])) return e;
else if (e[1] == null) return true;
else return null;
} else if (e[0] === "IS NOT NULL") {
if (isArray(e[1])) return e;
else if (e[1] != null) return true;
else return null;
} else if (e[0] === "LIKE") {
if (isArray(e[1]) || isArray(e[2]) || isArray(e[3])) return e;
else if (
e[1] == null ||
e[2] == null ||
((e as any[]).length >= 4 && e[3] == null)
)
return null;
let r = regExpCache.get(e as any[]);
if (!r) {
r = likePatternToRegExp(e[2], e[3]);
regExpCache.set(e as any[], r);
}
return r.test(e[1]);
} else if (e[0] === "NOT LIKE") {
if (isArray(e[1]) || isArray(e[2]) || isArray(e[3])) return e;
else if (
e[1] == null ||
e[2] == null ||
((e as any[]).length >= 4 && e[3] == null)
)
return null;
let r = regExpCache.get(e as any[]);
if (!r) {
r = likePatternToRegExp(e[2], e[3]);
regExpCache.set(e as any[], r);
}
return !r.test(e[1]);
} else if (e[0] === "=") {
if (isArray(e[1]) || isArray(e[2])) return e;
if (e[1] == null || e[2] == null) return null;
return e[1] === e[2];
} else if (e[0] === "<>") {
if (isArray(e[1]) || isArray(e[2])) return e;
if (e[1] == null || e[2] == null) return null;
return e[1] !== e[2];
} else if (e[0] === ">") {
if (isArray(e[1]) || isArray(e[2])) return e;
if (e[1] == null || e[2] == null) return null;
return e[1] > e[2];
} else if (e[0] === ">=") {
if (isArray(e[1]) || isArray(e[2])) return e;
if (e[1] == null || e[2] == null) return null;
return e[1] >= e[2];
} else if (e[0] === "<") {
if (isArray(e[1]) || isArray(e[2])) return e;
if (e[1] == null || e[2] == null) return null;
return e[1] < e[2];
} else if (e[0] === "<=") {
if (isArray(e[1]) || isArray(e[2])) return e;
if (e[1] == null || e[2] == null) return null;
return e[1] <= e[2];
} else if (e[0] === "*") {
return reduce(e, (a, b) => {
if (!isArray(a) && !isArray(b)) {
if (a == null || b == null) return null;
return a * b;
}
return REDUCE_SKIP;
});
} else if (e[0] === "/") {
return reduce(e, (a, b, i) => {
if (!isArray(a) && !isArray(b)) {
if (a == null || b == null) return null;
return i === 0 ? a / b : a * b;
}
return REDUCE_SKIP;
});
} else if (e[0] === "+") {
return reduce(e, (a, b) => {
if (!isArray(a) && !isArray(b)) {
if (a == null || b == null) return null;
return a + b;
}
return REDUCE_SKIP;
});
} else if (e[0] === "-") {
return reduce(e, (a, b, i) => {
if (!isArray(a) && !isArray(b)) {
if (a == null || b == null) return null;
return i === 0 ? a - b : a + b;
}
return REDUCE_SKIP;
});
} else if (e[0] === "||") {
return reduce(e, (a, b) => {
if (!isArray(a) && !isArray(b)) {
if (a == null || b == null) return null;
return `${a}${b}`;
}
return REDUCE_SKIP;
});
}
return e;
}
export function evaluate(
exp: Expression,
obj: Record<string, unknown> | ((exp: string) => Expression),
now: number,
cb?: (exp: Expression) => Expression
): string | number | boolean | null;
export function evaluate(
exp: Expression,
obj?: Record<string, unknown> | ((exp: string) => Expression),
now?: number,
cb?: (exp: Expression) => Expression
): Expression;
export function evaluate(
exp: Expression,
obj?: Record<string, unknown> | ((exp: string) => Expression),
now?: number,
cb?: (exp: Expression) => Expression
): Expression {
return map(exp, (e) => {
if (cb) e = cb(e);
if (!isArray(e)) return e;
if (e[0] === "FUNC") {
if (e[1] === "NOW") {
if (now) return now;
} else if (e[1] === "UPPER") {
if (e[2] == null) return null;
if (!isArray(e[2])) return `${e[2]}`.toUpperCase();
} else if (e[1] === "LOWER") {
if (e[2] == null) return null;
if (!isArray(e[2])) return `${e[2]}`.toLowerCase();
}
} else if (e[0] === "PARAM") {
if (e[1] == null) return null;
if (obj && !isArray(e[1])) {
let v;
if (typeof obj === "function") v = obj(e[1]);
else v = obj[e[1]];
if (v == null) return null;
if (typeof v === "object") v = v.value ? v.value[0] : null;
return v;
}
}
return evalExp(e);
});
}
export async function evaluateAsync(
exp: Expression,
obj: Record<string, unknown>,
now: number,
cb?: (exp: Expression) => Promise<Expression>
): Promise<string | number | boolean | null>;
export async function evaluateAsync(
exp: Expression,
obj?: Record<string, unknown>,
now?: number,
cb?: (exp: Expression) => Promise<Expression>
): Promise<Expression>;
export async function evaluateAsync(
exp: Expression,
obj?: Record<string, unknown>,
now?: number,
cb?: (exp: Expression) => Promise<Expression>
): Promise<Expression> {
return mapAsync(exp, async (e) => {
if (cb) e = await cb(e);
if (!isArray(e)) return e;
if (e[0] === "FUNC") {
if (e[1] === "NOW") {
if (now) return now;
} else if (e[1] === "UPPER") {
if (e[2] == null) return null;
if (!isArray(e[2])) return `${e[2]}`.toUpperCase();
} else if (e[1] === "LOWER") {
if (e[2] == null) return null;
if (!isArray(e[2])) return `${e[2]}`.toLowerCase();
}
} else if (e[0] === "PARAM") {
if (e[1] == null) return null;
if (obj && !isArray(e[1])) {
let v = obj[e[1]];
if (v == null) return null;
if (typeof v === "object") v = v["value"] ? v["value"][0] : null;
return v as Expression;
}
}
return evalExp(e);
});
}
export function and(exp1: Expression, exp2: Expression): Expression {
if (!isArray(exp1)) return exp1 ? exp2 : exp1;
if (!isArray(exp2)) return exp2 ? exp1 : exp2;
let res: Expression = ["AND"];
if (exp1[0] === "AND") res = res.concat(exp1.slice(1));
else res.push(exp1);
if (exp2[0] === "AND") res = res.concat(exp2.slice(1));
else res.push(exp2);
return res;
}
export function or(exp1: Expression, exp2: Expression): Expression {
if (!isArray(exp1)) return exp1 ? exp1 : exp2;
if (!isArray(exp2)) return exp2 ? exp2 : exp1;
let res: Expression = ["OR"];
if (exp1[0] === "OR") res = res.concat(exp1.slice(1));
else res.push(exp1);
if (exp2[0] === "OR") res = res.concat(exp2.slice(1));
else res.push(exp2);
return res;
}
export function extractParams(exp: Expression): Expression[] {
const params = new Set<Expression>();
map(exp, (e) => {
if (isArray(e) && e[0] === "PARAM") params.add(e[1]);
return e;
});
return Array.from(params);
}