typeorm
Version:
Data-Mapper ORM for TypeScript and ES2021+. Supports MySQL/MariaDB, PostgreSQL, MS SQL Server, Oracle, SAP HANA, SQLite, MongoDB databases.
175 lines (173 loc) • 7.62 kB
JavaScript
;
Object.defineProperty(exports, "__esModule", { value: true });
exports.SubjectTopologicalSorter = void 0;
const error_1 = require("../error");
/**
* Orders insert or remove subjects in proper order (using topological sorting)
* to make sure insert or remove operations are executed in a proper order.
*/
class SubjectTopologicalSorter {
// -------------------------------------------------------------------------
// Constructor
// -------------------------------------------------------------------------
constructor(subjects) {
this.subjects = [...subjects]; // copy subjects to prevent changing of sent array
this.metadatas = this.getUniqueMetadatas(this.subjects);
}
// -------------------------------------------------------------------------
// Public Methods
// -------------------------------------------------------------------------
/**
* Sorts (orders) subjects in their topological order.
*/
sort(direction) {
// if there are no metadatas it probably mean there is no subjects... we don't have to do anything here
if (!this.metadatas.length)
return this.subjects;
const sortedSubjects = [];
// first if we sort for deletion all junction subjects
// junction subjects are subjects without entity and database entity set
if (direction === "delete") {
const junctionSubjects = this.subjects.filter((subject) => !subject.entity && !subject.databaseEntity);
sortedSubjects.push(...junctionSubjects);
this.removeAlreadySorted(junctionSubjects);
}
// next we always insert entities with non-nullable relations, sort them first
const nonNullableDependencies = this.getNonNullableDependencies();
let sortedNonNullableEntityTargets = this.toposort(nonNullableDependencies);
if (direction === "insert")
sortedNonNullableEntityTargets =
sortedNonNullableEntityTargets.reverse();
// so we have a sorted entity targets
// go thought each of them and find all subjects with sorted entity target
// add those sorted targets and remove them from original array of targets
sortedNonNullableEntityTargets.forEach((sortedEntityTarget) => {
const entityTargetSubjects = this.subjects.filter((subject) => subject.metadata.targetName === sortedEntityTarget ||
subject.metadata.inheritanceTree.some((s) => s.name === sortedEntityTarget));
sortedSubjects.push(...entityTargetSubjects);
this.removeAlreadySorted(entityTargetSubjects);
});
// next sort all other entities
// same process as in above but with other entities
const otherDependencies = this.getDependencies();
let sortedOtherEntityTargets = this.toposort(otherDependencies);
if (direction === "insert")
sortedOtherEntityTargets = sortedOtherEntityTargets.reverse();
sortedOtherEntityTargets.forEach((sortedEntityTarget) => {
const entityTargetSubjects = this.subjects.filter((subject) => subject.metadata.targetName === sortedEntityTarget);
sortedSubjects.push(...entityTargetSubjects);
this.removeAlreadySorted(entityTargetSubjects);
});
// if we have something left in the subjects add them as well
sortedSubjects.push(...this.subjects);
return sortedSubjects;
}
// -------------------------------------------------------------------------
// Protected Methods
// -------------------------------------------------------------------------
/**
* Removes already sorted subjects from this.subjects list of subjects.
*/
removeAlreadySorted(subjects) {
subjects.forEach((subject) => {
this.subjects.splice(this.subjects.indexOf(subject), 1);
});
}
/**
* Extracts all unique metadatas from the given subjects.
*/
getUniqueMetadatas(subjects) {
const metadatas = [];
subjects.forEach((subject) => {
if (metadatas.indexOf(subject.metadata) === -1)
metadatas.push(subject.metadata);
});
return metadatas;
}
/**
* Gets dependency tree for all entity metadatas with non-nullable relations.
* We need to execute insertions first for entities which non-nullable relations.
*/
getNonNullableDependencies() {
return this.metadatas.reduce((dependencies, metadata) => {
metadata.relationsWithJoinColumns.forEach((relation) => {
if (relation.isNullable)
return;
dependencies.push([
metadata.targetName,
relation.inverseEntityMetadata.targetName,
]);
});
return dependencies;
}, []);
}
/**
* Gets dependency tree for all entity metadatas with non-nullable relations.
* We need to execute insertions first for entities which non-nullable relations.
*/
getDependencies() {
return this.metadatas.reduce((dependencies, metadata) => {
metadata.relationsWithJoinColumns.forEach((relation) => {
// if relation is self-referenced we skip it
if (relation.inverseEntityMetadata === metadata)
return;
dependencies.push([
metadata.targetName,
relation.inverseEntityMetadata.targetName,
]);
});
return dependencies;
}, []);
}
/**
* Sorts given graph using topological sorting algorithm.
*
* Algorithm is kindly taken from https://github.com/marcelklehr/toposort repository.
*/
toposort(edges) {
function uniqueNodes(arr) {
const res = [];
for (let i = 0, len = arr.length; i < len; i++) {
const edge = arr[i];
if (res.indexOf(edge[0]) < 0)
res.push(edge[0]);
if (res.indexOf(edge[1]) < 0)
res.push(edge[1]);
}
return res;
}
const nodes = uniqueNodes(edges);
let cursor = nodes.length, sorted = new Array(cursor), visited = {}, i = cursor;
while (i--) {
if (!visited[i])
visit(nodes[i], i, []);
}
function visit(node, i, predecessors) {
if (predecessors.indexOf(node) >= 0) {
throw new error_1.TypeORMError("Cyclic dependency: " + JSON.stringify(node)); // todo: better error
}
if (!~nodes.indexOf(node)) {
throw new error_1.TypeORMError("Found unknown node. Make sure to provided all involved nodes. Unknown node: " +
JSON.stringify(node));
}
if (visited[i])
return;
visited[i] = true;
// outgoing edges
const outgoing = edges.filter(function (edge) {
return edge[0] === node;
});
if ((i = outgoing.length)) {
const preds = predecessors.concat(node);
do {
const child = outgoing[--i][1];
visit(child, nodes.indexOf(child), preds);
} while (i);
}
sorted[--cursor] = node;
}
return sorted;
}
}
exports.SubjectTopologicalSorter = SubjectTopologicalSorter;
//# sourceMappingURL=SubjectTopologicalSorter.js.map