@memberjunction/record-graph

Generalized record dependency graph traversal, relationship collection resolution, topological sorting, link value encoding, and graph models for MemberJunction.

Shared across:

• Version History: Snapshot creation, dependency tracking, rollback / restore topological ordering.
• Record Cloning: Deep copying of record graphs, subtype rows, child collections, and soft-link rewriting.
• Metadata Sync: Deterministic 4-tier collection resolution and schema composition.

Installation

npm install @memberjunction/record-graph
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Key Components

1. DependencyGraphWalker

Walks an entity record's relationships to discover all dependent and referenced records.

import { CompositeKey } from '@memberjunction/core';
import { DependencyGraphWalker } from '@memberjunction/record-graph';

const walker = new DependencyGraphWalker(provider); // provider is optional; defaults to Metadata.Provider
const userKey = CompositeKey.FromID(userId);
const rootNode = await walker.WalkDependents(
  'MJ: Users',
  userKey,
  {
    MaxDepth: 3,
    RequireTrackRecordChanges: false, // Set false for cloning, true for Version History
    IncludeSubtypes: true,            // Include IS-A subtype rows
    FollowHierarchies: true,          // Recurse self-referencing hierarchy fields
    EdgePolicy: (candidate) => {
      if (candidate.TargetEntityName === 'MJ: Audit Logs') return 'Skip';
      if (candidate.Kind === 'ForwardFK') return 'Reference';
      return 'Deep';
    },
  },
  contextUser
);

const flatNodes = walker.FlattenTopological(rootNode);
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Traversal Rules & Discovery Modes

• Reverse Walk (Owned Children): Curated One-To-Many relationships (EntityRelationshipInfo) are walked with full discovery (both reverse and forward), discovering all dependent child records.
• Forward Walk (Referenced Records): Foreign key fields are walked in forward-only mode so referenced entities (e.g., shared lookup tables) do not traverse their own children, preventing graph explosion.
• Subtypes (IncludeSubtypes): Discovers IS-A subtype rows via FindISAChildEntities.
• Hierarchies (FollowHierarchies): Allows controlled recursion on fields whose Configuration.Hierarchy.IsHierarchy is true.
• Soft Links (IncludeSoftLinks): Traverses polymorphic EntityID/RecordID pairs via EntityIDFieldName.
• Non-Curated Inbound FKs (ListNonCuratedInbound): Discovers database foreign keys pointing to the record that lack a curated EntityRelationship.
• Edge Policy (EdgePolicy): Pre-traversal callback returning 'Deep', 'Reference', or 'Skip'.
• Cycle Prevention: Global visited set and entity-type ancestorStack to prevent infinite loops and backtracking.

2. Topological Sorting (sort.ts)

• SortByEntityDependencyOrder<T>(items, getEntityID, provider?): Computes DAG levels from foreign keys and sorts parent entities before child entities. Handles cycles safely.
• SortEntitiesByDependency: Backward-compatible alias for SortByEntityDependencyOrder.
• SortNodesTopologically(root: DependencyNode): Breadth-first traversal flattening a dependency tree into an execution-safe array where parents precede children.

3. Link Value Encoding (links.ts)

• ResolveLinkValue(kindOrIsSoft, targetKey): Resolves the value to write into a pointer or foreign key column:
  • Hard link ('hard' or false): bare primary key value (targetKey.GetValueByIndex(0)).
  • Soft link ('soft' or true): canonical prefixed polymorphic encoding (targetKey.ToRecordID()).

4. Collection Resolver (collection-resolver.ts)

• ResolveCollectionRelationship(entityInfo, colName) (resolveCollectionRelationship is a deprecated alias): Resolves a collection name to its matching relationship on the entity using strict 4-tier rule strength:
  1. Explicit collection name in RelatedRecordCollection JSON ("Name": "...")
  2. Relationship DisplayName
  3. RelatedEntity full name
  4. Stripped RelatedEntity name (with singular/plural tolerance)

5. SQL & Key Utilities (sql.ts, keys.ts)

• SqlEquals, SqlContains, SqlIn, SqlNotIn: Safe SQL filter builders (they escape with EscapeSQLString from @memberjunction/global).
• BuildCompositeKeyFromRecord, BuildPrimaryKeyForLoad, BuildIdKey: CompositeKey construction utilities.
• The camelCase names (sqlEquals, buildIdKey, …) and escapeSqlString are deprecated aliases. Use EscapeSQLString from @memberjunction/global directly.