Revert "Permission phase 2"

backend/src/lib/casl/knex.ts

@@ -0,0 +1,111 @@
+import { AnyAbility, ExtractSubjectType } from "@casl/ability";
+import { AbilityQuery, rulesToQuery } from "@casl/ability/extra";
+import { Tables } from "knex/types/tables";
+
+import { BadRequestError, UnauthorizedError } from "../errors";
+import { TKnexDynamicOperator } from "../knex/dynamic";
+
+type TBuildKnexQueryFromCaslDTO<K extends AnyAbility> = {
+  ability: K;
+  subject: ExtractSubjectType<Parameters<K["rulesFor"]>[1]>;
+  action: Parameters<K["rulesFor"]>[0];
+};
+
+export const buildKnexQueryFromCaslOperators = <K extends AnyAbility>({
+  ability,
+  subject,
+  action
+}: TBuildKnexQueryFromCaslDTO<K>) => {
+  const query = rulesToQuery(ability, action, subject, (rule) => {
+    if (!rule.ast) throw new Error("Ast not defined");
+    return rule.ast;
+  });
+
+  if (query === null) throw new UnauthorizedError({ message: `You don't have permission to do ${action} ${subject}` });
+  return query;
+};
+
+type TFieldMapper<T extends keyof Tables> = {
+  [K in T]: `${K}.${Exclude<keyof Tables[K]["base"], symbol>}`;
+}[T];
+
+type TFormatCaslFieldsWithTableNames<T extends keyof Tables> = {
+  // handle if any missing operator else throw error let the app break because this is executing again the db
+  missingOperatorCallback?: (operator: string) => void;
+  fieldMapping: (arg: string) => TFieldMapper<T> | null;
+  dynamicQuery: TKnexDynamicOperator;
+};
+
+export const formatCaslOperatorFieldsWithTableNames = <T extends keyof Tables>({
+  missingOperatorCallback = (arg) => {
+    throw new BadRequestError({ message: `Unknown permission operator: ${arg}` });
+  },
+  dynamicQuery: dynamicQueryAst,
+  fieldMapping
+}: TFormatCaslFieldsWithTableNames<T>) => {
+  const stack: [TKnexDynamicOperator, TKnexDynamicOperator | null][] = [[dynamicQueryAst, null]];
+
+  while (stack.length) {
+    const [filterAst, parentAst] = stack.pop()!;
+
+    if (filterAst.operator === "and" || filterAst.operator === "or" || filterAst.operator === "not") {
+      filterAst.value.forEach((el) => {
+        stack.push([el, filterAst]);
+      });
+
+      // eslint-disable-next-line no-continue
+      continue;
+    }
+
+    if (
+      filterAst.operator === "eq" ||
+      filterAst.operator === "ne" ||
+      filterAst.operator === "in" ||
+      filterAst.operator === "endsWith" ||
+      filterAst.operator === "startsWith"
+    ) {
+      const attrPath = fieldMapping(filterAst.field);
+      if (attrPath) {
+        filterAst.field = attrPath;
+      } else if (parentAst && Array.isArray(parentAst.value)) {
+        parentAst.value = parentAst.value.filter((childAst) => childAst !== filterAst) as string[];
+      } else throw new Error("Unknown casl field");
+      // eslint-disable-next-line no-continue
+      continue;
+    }
+
+    if (parentAst && Array.isArray(parentAst.value)) {
+      parentAst.value = parentAst.value.filter((childAst) => childAst !== filterAst) as string[];
+    } else {
+      missingOperatorCallback?.(filterAst.operator);
+    }
+  }
+  return dynamicQueryAst;
+};
+
+export const convertCaslOperatorToKnexOperator = <T extends keyof Tables>(
+  caslKnexOperators: AbilityQuery,
+  fieldMapping: (arg: string) => TFieldMapper<T> | null
+) => {
+  const value = [];
+  if (caslKnexOperators.$and) {
+    value.push({
+      operator: "not" as const,
+      value: caslKnexOperators.$and as TKnexDynamicOperator[]
+    });
+  }
+  if (caslKnexOperators.$or) {
+    value.push({
+      operator: "or" as const,
+      value: caslKnexOperators.$or as TKnexDynamicOperator[]
+    });
+  }
+
+  return formatCaslOperatorFieldsWithTableNames({
+    dynamicQuery: {
+      operator: "and",
+      value
+    },
+    fieldMapping
+  });
+};