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silverbullet/packages/plugs/query/parser.ts
2022-08-09 15:37:47 +02:00

97 lines
2.7 KiB
TypeScript

import {
collectNodesOfType,
findNodeOfType,
replaceNodesMatching,
} from "@silverbulletmd/common/tree";
import { lezerToParseTree } from "@silverbulletmd/common/parse_tree";
import { valueNodeToVal } from "./engine";
// @ts-ignore
import { parser } from "./parse-query";
export type Filter = {
op: string;
prop: string;
value: any;
};
export type ParsedQuery = {
table: string;
orderBy?: string;
orderDesc?: boolean;
limit?: number;
filter: Filter[];
select?: string[];
render?: string;
};
export function parseQuery(query: string): ParsedQuery {
let n = lezerToParseTree(query, parser.parse(query).topNode);
// Clean the tree a bit
replaceNodesMatching(n, (n) => {
if (!n.type) {
let trimmed = n.text!.trim();
if (!trimmed) {
return null;
}
n.text = trimmed;
}
});
// console.log("Parsed", JSON.stringify(n, null, 2));
let queryNode = n.children![0];
let parsedQuery: ParsedQuery = {
table: queryNode.children![0].children![0].text!,
filter: [],
};
let orderByNode = findNodeOfType(queryNode, "OrderClause");
if (orderByNode) {
let nameNode = findNodeOfType(orderByNode, "Name");
parsedQuery.orderBy = nameNode!.children![0].text!;
let orderNode = findNodeOfType(orderByNode, "Order");
parsedQuery.orderDesc = orderNode
? orderNode.children![0].text! === "desc"
: false;
}
let limitNode = findNodeOfType(queryNode, "LimitClause");
if (limitNode) {
let nameNode = findNodeOfType(limitNode, "Number");
parsedQuery.limit = valueNodeToVal(nameNode!);
}
let filterNodes = collectNodesOfType(queryNode, "FilterExpr");
for (let filterNode of filterNodes) {
let val: any = undefined;
let valNode = filterNode.children![2].children![0];
val = valueNodeToVal(valNode);
let f: Filter = {
prop: filterNode.children![0].children![0].text!,
op: filterNode.children![1].text!,
value: val,
};
parsedQuery.filter.push(f);
}
let selectNode = findNodeOfType(queryNode, "SelectClause");
if (selectNode) {
// console.log("Select node", JSON.stringify(selectNode));
parsedQuery.select = [];
collectNodesOfType(selectNode, "Name").forEach((t) => {
parsedQuery.select!.push(t.children![0].text!);
});
// let nameNode = findNodeOfType(selectNode, "Number");
// parsedQuery.limit = +nameNode!.children![0].text!;
}
let renderNode = findNodeOfType(queryNode, "RenderClause");
if (renderNode) {
let renderNameNode = findNodeOfType(renderNode, "PageRef");
if (!renderNameNode) {
renderNameNode = findNodeOfType(renderNode, "String");
}
parsedQuery.render = valueNodeToVal(renderNameNode!);
}
// console.log(JSON.stringify(queryNode, null, 2));
return parsedQuery;
}