Merge pull request 'feat: Add semantic search with pgvector (closes #68, #69, #70)' (#119) from feature/semantic-search into develop
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Reviewed-on: #119
This commit was merged in pull request #119.
This commit is contained in:
@@ -88,6 +88,14 @@ JWT_EXPIRATION=24h
|
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OLLAMA_ENDPOINT=http://ollama:11434
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OLLAMA_PORT=11434
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|
||||
# ======================
|
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# OpenAI API (For Semantic Search)
|
||||
# ======================
|
||||
# OPTIONAL: Semantic search requires an OpenAI API key
|
||||
# Get your API key from: https://platform.openai.com/api-keys
|
||||
# If not configured, semantic search endpoints will return an error
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||||
# OPENAI_API_KEY=sk-...
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||||
|
||||
# ======================
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||||
# Application Environment
|
||||
# ======================
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||||
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@@ -48,6 +48,7 @@
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"marked-gfm-heading-id": "^4.1.3",
|
||||
"marked-highlight": "^2.2.3",
|
||||
"ollama": "^0.6.3",
|
||||
"openai": "^6.17.0",
|
||||
"reflect-metadata": "^0.2.2",
|
||||
"rxjs": "^7.8.1",
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||||
"sanitize-html": "^2.17.0",
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@@ -0,0 +1,8 @@
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-- Add HNSW index for fast vector similarity search on knowledge_embeddings table
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-- Using cosine distance operator for semantic similarity
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-- Parameters: m=16 (max connections per layer), ef_construction=64 (build quality)
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CREATE INDEX IF NOT EXISTS knowledge_embeddings_embedding_idx
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ON knowledge_embeddings
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USING hnsw (embedding vector_cosine_ops)
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WITH (m = 16, ef_construction = 64);
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@@ -12,6 +12,7 @@ import {
|
||||
DefaultValuePipe,
|
||||
} from "@nestjs/common";
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||||
import type { AuthUser } from "@mosaic/shared";
|
||||
import { EntryStatus } from "@prisma/client";
|
||||
import { KnowledgeService } from "./knowledge.service";
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||||
import { CreateEntryDto, UpdateEntryDto, EntryQueryDto, RestoreVersionDto } from "./dto";
|
||||
import { AuthGuard } from "../auth/guards/auth.guard";
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||||
@@ -192,6 +193,38 @@ export class KnowledgeController {
|
||||
}
|
||||
}
|
||||
|
||||
/**
|
||||
* Controller for knowledge embeddings endpoints
|
||||
*/
|
||||
@Controller("knowledge/embeddings")
|
||||
@UseGuards(AuthGuard, WorkspaceGuard, PermissionGuard)
|
||||
export class KnowledgeEmbeddingsController {
|
||||
constructor(private readonly knowledgeService: KnowledgeService) {}
|
||||
|
||||
/**
|
||||
* POST /api/knowledge/embeddings/batch
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||||
* Batch generate embeddings for all entries in the workspace
|
||||
* Useful for populating embeddings for existing entries
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||||
* Requires: ADMIN role or higher
|
||||
*/
|
||||
@Post("batch")
|
||||
@RequirePermission(Permission.WORKSPACE_ADMIN)
|
||||
async batchGenerate(
|
||||
@Workspace() workspaceId: string,
|
||||
@Body() body: { status?: string }
|
||||
) {
|
||||
const status = body.status as EntryStatus | undefined;
|
||||
const result = await this.knowledgeService.batchGenerateEmbeddings(
|
||||
workspaceId,
|
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status
|
||||
);
|
||||
return {
|
||||
message: `Generated ${result.success} embeddings out of ${result.total} entries`,
|
||||
...result,
|
||||
};
|
||||
}
|
||||
}
|
||||
|
||||
/**
|
||||
* Controller for knowledge cache endpoints
|
||||
*/
|
||||
|
||||
@@ -2,7 +2,11 @@ import { Module } from "@nestjs/common";
|
||||
import { PrismaModule } from "../prisma/prisma.module";
|
||||
import { AuthModule } from "../auth/auth.module";
|
||||
import { KnowledgeService } from "./knowledge.service";
|
||||
import { KnowledgeController, KnowledgeCacheController } from "./knowledge.controller";
|
||||
import {
|
||||
KnowledgeController,
|
||||
KnowledgeCacheController,
|
||||
KnowledgeEmbeddingsController,
|
||||
} from "./knowledge.controller";
|
||||
import { SearchController } from "./search.controller";
|
||||
import { KnowledgeStatsController } from "./stats.controller";
|
||||
import {
|
||||
@@ -12,6 +16,7 @@ import {
|
||||
GraphService,
|
||||
StatsService,
|
||||
KnowledgeCacheService,
|
||||
EmbeddingService,
|
||||
} from "./services";
|
||||
|
||||
@Module({
|
||||
@@ -19,6 +24,7 @@ import {
|
||||
controllers: [
|
||||
KnowledgeController,
|
||||
KnowledgeCacheController,
|
||||
KnowledgeEmbeddingsController,
|
||||
SearchController,
|
||||
KnowledgeStatsController,
|
||||
],
|
||||
@@ -30,7 +36,8 @@ import {
|
||||
GraphService,
|
||||
StatsService,
|
||||
KnowledgeCacheService,
|
||||
EmbeddingService,
|
||||
],
|
||||
exports: [KnowledgeService, LinkResolutionService, SearchService],
|
||||
exports: [KnowledgeService, LinkResolutionService, SearchService, EmbeddingService],
|
||||
})
|
||||
export class KnowledgeModule {}
|
||||
|
||||
@@ -18,6 +18,7 @@ import type {
|
||||
import { renderMarkdown } from "./utils/markdown";
|
||||
import { LinkSyncService } from "./services/link-sync.service";
|
||||
import { KnowledgeCacheService } from "./services/cache.service";
|
||||
import { EmbeddingService } from "./services/embedding.service";
|
||||
|
||||
/**
|
||||
* Service for managing knowledge entries
|
||||
@@ -27,7 +28,8 @@ export class KnowledgeService {
|
||||
constructor(
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||||
private readonly prisma: PrismaService,
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||||
private readonly linkSync: LinkSyncService,
|
||||
private readonly cache: KnowledgeCacheService
|
||||
private readonly cache: KnowledgeCacheService,
|
||||
private readonly embedding: EmbeddingService
|
||||
) {}
|
||||
|
||||
|
||||
@@ -250,6 +252,13 @@ export class KnowledgeService {
|
||||
// Sync wiki links after entry creation
|
||||
await this.linkSync.syncLinks(workspaceId, result.id, createDto.content);
|
||||
|
||||
// Generate and store embedding asynchronously (don't block the response)
|
||||
this.generateEntryEmbedding(result.id, result.title, result.content).catch(
|
||||
(error) => {
|
||||
console.error(`Failed to generate embedding for entry ${result.id}:`, error);
|
||||
}
|
||||
);
|
||||
|
||||
// Invalidate search and graph caches (new entry affects search results)
|
||||
await this.cache.invalidateSearches(workspaceId);
|
||||
await this.cache.invalidateGraphs(workspaceId);
|
||||
@@ -408,6 +417,15 @@ export class KnowledgeService {
|
||||
await this.linkSync.syncLinks(workspaceId, result.id, result.content);
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||||
}
|
||||
|
||||
// Regenerate embedding if content or title changed (async, don't block response)
|
||||
if (updateDto.content !== undefined || updateDto.title !== undefined) {
|
||||
this.generateEntryEmbedding(result.id, result.title, result.content).catch(
|
||||
(error) => {
|
||||
console.error(`Failed to generate embedding for entry ${result.id}:`, error);
|
||||
}
|
||||
);
|
||||
}
|
||||
|
||||
// Invalidate caches
|
||||
// Invalidate old slug cache if slug changed
|
||||
if (newSlug !== slug) {
|
||||
@@ -863,4 +881,64 @@ export class KnowledgeService {
|
||||
)
|
||||
);
|
||||
}
|
||||
|
||||
/**
|
||||
* Generate and store embedding for a knowledge entry
|
||||
* Private helper method called asynchronously after entry create/update
|
||||
*/
|
||||
private async generateEntryEmbedding(
|
||||
entryId: string,
|
||||
title: string,
|
||||
content: string
|
||||
): Promise<void> {
|
||||
const combinedContent = this.embedding.prepareContentForEmbedding(
|
||||
title,
|
||||
content
|
||||
);
|
||||
await this.embedding.generateAndStoreEmbedding(entryId, combinedContent);
|
||||
}
|
||||
|
||||
/**
|
||||
* Batch generate embeddings for all entries in a workspace
|
||||
* Useful for populating embeddings for existing entries
|
||||
*
|
||||
* @param workspaceId - The workspace ID
|
||||
* @param status - Optional status filter (default: not ARCHIVED)
|
||||
* @returns Number of embeddings successfully generated
|
||||
*/
|
||||
async batchGenerateEmbeddings(
|
||||
workspaceId: string,
|
||||
status?: EntryStatus
|
||||
): Promise<{ total: number; success: number }> {
|
||||
const where: Prisma.KnowledgeEntryWhereInput = {
|
||||
workspaceId,
|
||||
status: status || { not: EntryStatus.ARCHIVED },
|
||||
};
|
||||
|
||||
const entries = await this.prisma.knowledgeEntry.findMany({
|
||||
where,
|
||||
select: {
|
||||
id: true,
|
||||
title: true,
|
||||
content: true,
|
||||
},
|
||||
});
|
||||
|
||||
const entriesForEmbedding = entries.map((entry) => ({
|
||||
id: entry.id,
|
||||
content: this.embedding.prepareContentForEmbedding(
|
||||
entry.title,
|
||||
entry.content
|
||||
),
|
||||
}));
|
||||
|
||||
const successCount = await this.embedding.batchGenerateEmbeddings(
|
||||
entriesForEmbedding
|
||||
);
|
||||
|
||||
return {
|
||||
total: entries.length,
|
||||
success: successCount,
|
||||
};
|
||||
}
|
||||
}
|
||||
|
||||
@@ -1,9 +1,10 @@
|
||||
import { Controller, Get, Query, UseGuards } from "@nestjs/common";
|
||||
import { Controller, Get, Post, Body, Query, UseGuards } from "@nestjs/common";
|
||||
import { SearchService, PaginatedSearchResults } from "./services/search.service";
|
||||
import { SearchQueryDto, TagSearchDto, RecentEntriesDto } from "./dto";
|
||||
import { AuthGuard } from "../auth/guards/auth.guard";
|
||||
import { WorkspaceGuard, PermissionGuard } from "../common/guards";
|
||||
import { Workspace, Permission, RequirePermission } from "../common/decorators";
|
||||
import { EntryStatus } from "@prisma/client";
|
||||
import type {
|
||||
PaginatedEntries,
|
||||
KnowledgeEntryWithTags,
|
||||
@@ -97,4 +98,55 @@ export class SearchController {
|
||||
count: entries.length,
|
||||
};
|
||||
}
|
||||
|
||||
/**
|
||||
* POST /api/knowledge/search/semantic
|
||||
* Semantic search using vector similarity
|
||||
* Requires: Any workspace member, OpenAI API key configured
|
||||
*
|
||||
* @body query - The search query string (required)
|
||||
* @body status - Filter by entry status (optional)
|
||||
* @query page - Page number (default: 1)
|
||||
* @query limit - Results per page (default: 20, max: 100)
|
||||
*/
|
||||
@Post("semantic")
|
||||
@RequirePermission(Permission.WORKSPACE_ANY)
|
||||
async semanticSearch(
|
||||
@Workspace() workspaceId: string,
|
||||
@Body() body: { query: string; status?: EntryStatus },
|
||||
@Query("page") page?: number,
|
||||
@Query("limit") limit?: number
|
||||
): Promise<PaginatedSearchResults> {
|
||||
return this.searchService.semanticSearch(body.query, workspaceId, {
|
||||
status: body.status,
|
||||
page,
|
||||
limit,
|
||||
});
|
||||
}
|
||||
|
||||
/**
|
||||
* POST /api/knowledge/search/hybrid
|
||||
* Hybrid search combining vector similarity and full-text search
|
||||
* Uses Reciprocal Rank Fusion to merge results
|
||||
* Requires: Any workspace member
|
||||
*
|
||||
* @body query - The search query string (required)
|
||||
* @body status - Filter by entry status (optional)
|
||||
* @query page - Page number (default: 1)
|
||||
* @query limit - Results per page (default: 20, max: 100)
|
||||
*/
|
||||
@Post("hybrid")
|
||||
@RequirePermission(Permission.WORKSPACE_ANY)
|
||||
async hybridSearch(
|
||||
@Workspace() workspaceId: string,
|
||||
@Body() body: { query: string; status?: EntryStatus },
|
||||
@Query("page") page?: number,
|
||||
@Query("limit") limit?: number
|
||||
): Promise<PaginatedSearchResults> {
|
||||
return this.searchService.hybridSearch(body.query, workspaceId, {
|
||||
status: body.status,
|
||||
page,
|
||||
limit,
|
||||
});
|
||||
}
|
||||
}
|
||||
|
||||
115
apps/api/src/knowledge/services/embedding.service.spec.ts
Normal file
115
apps/api/src/knowledge/services/embedding.service.spec.ts
Normal file
@@ -0,0 +1,115 @@
|
||||
import { describe, it, expect, beforeEach, vi } from "vitest";
|
||||
import { EmbeddingService } from "./embedding.service";
|
||||
import { PrismaService } from "../../prisma/prisma.service";
|
||||
|
||||
describe("EmbeddingService", () => {
|
||||
let service: EmbeddingService;
|
||||
let prismaService: PrismaService;
|
||||
|
||||
beforeEach(() => {
|
||||
prismaService = {
|
||||
$executeRaw: vi.fn(),
|
||||
knowledgeEmbedding: {
|
||||
deleteMany: vi.fn(),
|
||||
},
|
||||
} as unknown as PrismaService;
|
||||
|
||||
service = new EmbeddingService(prismaService);
|
||||
});
|
||||
|
||||
describe("isConfigured", () => {
|
||||
it("should return false when OPENAI_API_KEY is not set", () => {
|
||||
const originalEnv = process.env["OPENAI_API_KEY"];
|
||||
delete process.env["OPENAI_API_KEY"];
|
||||
|
||||
expect(service.isConfigured()).toBe(false);
|
||||
|
||||
if (originalEnv) {
|
||||
process.env["OPENAI_API_KEY"] = originalEnv;
|
||||
}
|
||||
});
|
||||
|
||||
it("should return true when OPENAI_API_KEY is set", () => {
|
||||
const originalEnv = process.env["OPENAI_API_KEY"];
|
||||
process.env["OPENAI_API_KEY"] = "test-key";
|
||||
|
||||
expect(service.isConfigured()).toBe(true);
|
||||
|
||||
if (originalEnv) {
|
||||
process.env["OPENAI_API_KEY"] = originalEnv;
|
||||
} else {
|
||||
delete process.env["OPENAI_API_KEY"];
|
||||
}
|
||||
});
|
||||
});
|
||||
|
||||
describe("prepareContentForEmbedding", () => {
|
||||
it("should combine title and content with title weighting", () => {
|
||||
const title = "Test Title";
|
||||
const content = "Test content goes here";
|
||||
|
||||
const result = service.prepareContentForEmbedding(title, content);
|
||||
|
||||
expect(result).toContain(title);
|
||||
expect(result).toContain(content);
|
||||
// Title should appear twice for weighting
|
||||
expect(result.split(title).length - 1).toBe(2);
|
||||
});
|
||||
|
||||
it("should handle empty content", () => {
|
||||
const title = "Test Title";
|
||||
const content = "";
|
||||
|
||||
const result = service.prepareContentForEmbedding(title, content);
|
||||
|
||||
expect(result).toBe(`${title}\n\n${title}`);
|
||||
});
|
||||
});
|
||||
|
||||
describe("generateAndStoreEmbedding", () => {
|
||||
it("should skip generation when not configured", async () => {
|
||||
const originalEnv = process.env["OPENAI_API_KEY"];
|
||||
delete process.env["OPENAI_API_KEY"];
|
||||
|
||||
await service.generateAndStoreEmbedding("test-id", "test content");
|
||||
|
||||
expect(prismaService.$executeRaw).not.toHaveBeenCalled();
|
||||
|
||||
if (originalEnv) {
|
||||
process.env["OPENAI_API_KEY"] = originalEnv;
|
||||
}
|
||||
});
|
||||
});
|
||||
|
||||
describe("deleteEmbedding", () => {
|
||||
it("should delete embedding for entry", async () => {
|
||||
const entryId = "test-entry-id";
|
||||
|
||||
await service.deleteEmbedding(entryId);
|
||||
|
||||
expect(prismaService.knowledgeEmbedding.deleteMany).toHaveBeenCalledWith({
|
||||
where: { entryId },
|
||||
});
|
||||
});
|
||||
});
|
||||
|
||||
describe("batchGenerateEmbeddings", () => {
|
||||
it("should return 0 when not configured", async () => {
|
||||
const originalEnv = process.env["OPENAI_API_KEY"];
|
||||
delete process.env["OPENAI_API_KEY"];
|
||||
|
||||
const entries = [
|
||||
{ id: "1", content: "content 1" },
|
||||
{ id: "2", content: "content 2" },
|
||||
];
|
||||
|
||||
const result = await service.batchGenerateEmbeddings(entries);
|
||||
|
||||
expect(result).toBe(0);
|
||||
|
||||
if (originalEnv) {
|
||||
process.env["OPENAI_API_KEY"] = originalEnv;
|
||||
}
|
||||
});
|
||||
});
|
||||
});
|
||||
190
apps/api/src/knowledge/services/embedding.service.ts
Normal file
190
apps/api/src/knowledge/services/embedding.service.ts
Normal file
@@ -0,0 +1,190 @@
|
||||
import { Injectable, Logger } from "@nestjs/common";
|
||||
import OpenAI from "openai";
|
||||
import { PrismaService } from "../../prisma/prisma.service";
|
||||
import { EMBEDDING_DIMENSION } from "@mosaic/shared";
|
||||
|
||||
/**
|
||||
* Options for generating embeddings
|
||||
*/
|
||||
export interface EmbeddingOptions {
|
||||
/**
|
||||
* Model to use for embedding generation
|
||||
* @default "text-embedding-3-small"
|
||||
*/
|
||||
model?: string;
|
||||
}
|
||||
|
||||
/**
|
||||
* Service for generating and managing embeddings using OpenAI API
|
||||
*/
|
||||
@Injectable()
|
||||
export class EmbeddingService {
|
||||
private readonly logger = new Logger(EmbeddingService.name);
|
||||
private readonly openai: OpenAI;
|
||||
private readonly defaultModel = "text-embedding-3-small";
|
||||
|
||||
constructor(private readonly prisma: PrismaService) {
|
||||
const apiKey = process.env["OPENAI_API_KEY"];
|
||||
|
||||
if (!apiKey) {
|
||||
this.logger.warn("OPENAI_API_KEY not configured - embedding generation will be disabled");
|
||||
}
|
||||
|
||||
this.openai = new OpenAI({
|
||||
apiKey: apiKey || "dummy-key", // Provide dummy key to allow instantiation
|
||||
});
|
||||
}
|
||||
|
||||
/**
|
||||
* Check if the service is properly configured
|
||||
*/
|
||||
isConfigured(): boolean {
|
||||
return !!process.env["OPENAI_API_KEY"];
|
||||
}
|
||||
|
||||
/**
|
||||
* Generate an embedding vector for the given text
|
||||
*
|
||||
* @param text - Text to embed
|
||||
* @param options - Embedding generation options
|
||||
* @returns Embedding vector (array of numbers)
|
||||
* @throws Error if OpenAI API key is not configured
|
||||
*/
|
||||
async generateEmbedding(
|
||||
text: string,
|
||||
options: EmbeddingOptions = {}
|
||||
): Promise<number[]> {
|
||||
if (!this.isConfigured()) {
|
||||
throw new Error("OPENAI_API_KEY not configured");
|
||||
}
|
||||
|
||||
const model = options.model || this.defaultModel;
|
||||
|
||||
try {
|
||||
const response = await this.openai.embeddings.create({
|
||||
model,
|
||||
input: text,
|
||||
dimensions: EMBEDDING_DIMENSION,
|
||||
});
|
||||
|
||||
const embedding = response.data[0]?.embedding;
|
||||
|
||||
if (!embedding) {
|
||||
throw new Error("No embedding returned from OpenAI");
|
||||
}
|
||||
|
||||
if (embedding.length !== EMBEDDING_DIMENSION) {
|
||||
throw new Error(
|
||||
`Unexpected embedding dimension: ${embedding.length} (expected ${EMBEDDING_DIMENSION})`
|
||||
);
|
||||
}
|
||||
|
||||
return embedding;
|
||||
} catch (error) {
|
||||
this.logger.error("Failed to generate embedding", error);
|
||||
throw error;
|
||||
}
|
||||
}
|
||||
|
||||
/**
|
||||
* Generate and store embedding for a knowledge entry
|
||||
*
|
||||
* @param entryId - ID of the knowledge entry
|
||||
* @param content - Content to embed (typically title + content)
|
||||
* @param options - Embedding generation options
|
||||
* @returns Created/updated embedding record
|
||||
*/
|
||||
async generateAndStoreEmbedding(
|
||||
entryId: string,
|
||||
content: string,
|
||||
options: EmbeddingOptions = {}
|
||||
): Promise<void> {
|
||||
if (!this.isConfigured()) {
|
||||
this.logger.warn(`Skipping embedding generation for entry ${entryId} - OpenAI not configured`);
|
||||
return;
|
||||
}
|
||||
|
||||
const model = options.model || this.defaultModel;
|
||||
const embedding = await this.generateEmbedding(content, { model });
|
||||
|
||||
// Convert to Prisma-compatible format
|
||||
const embeddingString = `[${embedding.join(",")}]`;
|
||||
|
||||
// Upsert the embedding
|
||||
await this.prisma.$executeRaw`
|
||||
INSERT INTO knowledge_embeddings (id, entry_id, embedding, model, created_at, updated_at)
|
||||
VALUES (
|
||||
gen_random_uuid(),
|
||||
${entryId}::uuid,
|
||||
${embeddingString}::vector(${EMBEDDING_DIMENSION}),
|
||||
${model},
|
||||
NOW(),
|
||||
NOW()
|
||||
)
|
||||
ON CONFLICT (entry_id) DO UPDATE SET
|
||||
embedding = ${embeddingString}::vector(${EMBEDDING_DIMENSION}),
|
||||
model = ${model},
|
||||
updated_at = NOW()
|
||||
`;
|
||||
|
||||
this.logger.log(`Generated and stored embedding for entry ${entryId}`);
|
||||
}
|
||||
|
||||
/**
|
||||
* Batch process embeddings for multiple entries
|
||||
*
|
||||
* @param entries - Array of {id, content} objects
|
||||
* @param options - Embedding generation options
|
||||
* @returns Number of embeddings successfully generated
|
||||
*/
|
||||
async batchGenerateEmbeddings(
|
||||
entries: Array<{ id: string; content: string }>,
|
||||
options: EmbeddingOptions = {}
|
||||
): Promise<number> {
|
||||
if (!this.isConfigured()) {
|
||||
this.logger.warn("Skipping batch embedding generation - OpenAI not configured");
|
||||
return 0;
|
||||
}
|
||||
|
||||
let successCount = 0;
|
||||
|
||||
for (const entry of entries) {
|
||||
try {
|
||||
await this.generateAndStoreEmbedding(entry.id, entry.content, options);
|
||||
successCount++;
|
||||
} catch (error) {
|
||||
this.logger.error(`Failed to generate embedding for entry ${entry.id}`, error);
|
||||
}
|
||||
}
|
||||
|
||||
this.logger.log(`Batch generated ${successCount}/${entries.length} embeddings`);
|
||||
return successCount;
|
||||
}
|
||||
|
||||
/**
|
||||
* Delete embedding for a knowledge entry
|
||||
*
|
||||
* @param entryId - ID of the knowledge entry
|
||||
*/
|
||||
async deleteEmbedding(entryId: string): Promise<void> {
|
||||
await this.prisma.knowledgeEmbedding.deleteMany({
|
||||
where: { entryId },
|
||||
});
|
||||
|
||||
this.logger.log(`Deleted embedding for entry ${entryId}`);
|
||||
}
|
||||
|
||||
/**
|
||||
* Prepare content for embedding
|
||||
* Combines title and content with appropriate weighting
|
||||
*
|
||||
* @param title - Entry title
|
||||
* @param content - Entry content (markdown)
|
||||
* @returns Combined text for embedding
|
||||
*/
|
||||
prepareContentForEmbedding(title: string, content: string): string {
|
||||
// Weight title more heavily by repeating it
|
||||
// This helps with semantic search matching on titles
|
||||
return `${title}\n\n${title}\n\n${content}`.trim();
|
||||
}
|
||||
}
|
||||
@@ -10,3 +10,5 @@ export { GraphService } from "./graph.service";
|
||||
export { StatsService } from "./stats.service";
|
||||
export { KnowledgeCacheService } from "./cache.service";
|
||||
export type { CacheStats, CacheOptions } from "./cache.service";
|
||||
export { EmbeddingService } from "./embedding.service";
|
||||
export type { EmbeddingOptions } from "./embedding.service";
|
||||
|
||||
@@ -6,6 +6,7 @@ import type {
|
||||
PaginatedEntries,
|
||||
} from "../entities/knowledge-entry.entity";
|
||||
import { KnowledgeCacheService } from "./cache.service";
|
||||
import { EmbeddingService } from "./embedding.service";
|
||||
|
||||
/**
|
||||
* Search options for full-text search
|
||||
@@ -66,7 +67,8 @@ interface RawSearchResult {
|
||||
export class SearchService {
|
||||
constructor(
|
||||
private readonly prisma: PrismaService,
|
||||
private readonly cache: KnowledgeCacheService
|
||||
private readonly cache: KnowledgeCacheService,
|
||||
private readonly embedding: EmbeddingService
|
||||
) {}
|
||||
|
||||
/**
|
||||
@@ -428,4 +430,288 @@ export class SearchService {
|
||||
|
||||
return tagsMap;
|
||||
}
|
||||
|
||||
/**
|
||||
* Semantic search using vector similarity
|
||||
*
|
||||
* @param query - The search query string
|
||||
* @param workspaceId - The workspace to search within
|
||||
* @param options - Search options (status filter, pagination)
|
||||
* @returns Paginated search results ranked by semantic similarity
|
||||
*/
|
||||
async semanticSearch(
|
||||
query: string,
|
||||
workspaceId: string,
|
||||
options: SearchOptions = {}
|
||||
): Promise<PaginatedSearchResults> {
|
||||
if (!this.embedding.isConfigured()) {
|
||||
throw new Error("Semantic search requires OPENAI_API_KEY to be configured");
|
||||
}
|
||||
|
||||
const page = options.page || 1;
|
||||
const limit = options.limit || 20;
|
||||
const offset = (page - 1) * limit;
|
||||
|
||||
// Generate embedding for the query
|
||||
const queryEmbedding = await this.embedding.generateEmbedding(query);
|
||||
const embeddingString = `[${queryEmbedding.join(",")}]`;
|
||||
|
||||
// Build status filter
|
||||
const statusFilter = options.status
|
||||
? Prisma.sql`AND e.status = ${options.status}::text::"EntryStatus"`
|
||||
: Prisma.sql`AND e.status != 'ARCHIVED'`;
|
||||
|
||||
// Vector similarity search using cosine distance
|
||||
const searchResults = await this.prisma.$queryRaw<RawSearchResult[]>`
|
||||
SELECT
|
||||
e.id,
|
||||
e.workspace_id,
|
||||
e.slug,
|
||||
e.title,
|
||||
e.content,
|
||||
e.content_html,
|
||||
e.summary,
|
||||
e.status,
|
||||
e.visibility,
|
||||
e.created_at,
|
||||
e.updated_at,
|
||||
e.created_by,
|
||||
e.updated_by,
|
||||
(1 - (emb.embedding <=> ${embeddingString}::vector)) AS rank,
|
||||
NULL AS headline
|
||||
FROM knowledge_entries e
|
||||
INNER JOIN knowledge_embeddings emb ON e.id = emb.entry_id
|
||||
WHERE e.workspace_id = ${workspaceId}::uuid
|
||||
${statusFilter}
|
||||
ORDER BY emb.embedding <=> ${embeddingString}::vector
|
||||
LIMIT ${limit}
|
||||
OFFSET ${offset}
|
||||
`;
|
||||
|
||||
// Get total count for pagination
|
||||
const countResult = await this.prisma.$queryRaw<[{ count: bigint }]>`
|
||||
SELECT COUNT(*) as count
|
||||
FROM knowledge_entries e
|
||||
INNER JOIN knowledge_embeddings emb ON e.id = emb.entry_id
|
||||
WHERE e.workspace_id = ${workspaceId}::uuid
|
||||
${statusFilter}
|
||||
`;
|
||||
|
||||
const total = Number(countResult[0].count);
|
||||
|
||||
// Fetch tags for the results
|
||||
const entryIds = searchResults.map((r) => r.id);
|
||||
const tagsMap = await this.fetchTagsForEntries(entryIds);
|
||||
|
||||
// Transform results to the expected format
|
||||
const data: SearchResult[] = searchResults.map((row) => ({
|
||||
id: row.id,
|
||||
workspaceId: row.workspace_id,
|
||||
slug: row.slug,
|
||||
title: row.title,
|
||||
content: row.content,
|
||||
contentHtml: row.content_html,
|
||||
summary: row.summary,
|
||||
status: row.status,
|
||||
visibility: row.visibility as "PRIVATE" | "WORKSPACE" | "PUBLIC",
|
||||
createdAt: row.created_at,
|
||||
updatedAt: row.updated_at,
|
||||
createdBy: row.created_by,
|
||||
updatedBy: row.updated_by,
|
||||
rank: row.rank,
|
||||
headline: row.headline ?? undefined,
|
||||
tags: tagsMap.get(row.id) || [],
|
||||
}));
|
||||
|
||||
return {
|
||||
data,
|
||||
pagination: {
|
||||
page,
|
||||
limit,
|
||||
total,
|
||||
totalPages: Math.ceil(total / limit),
|
||||
},
|
||||
query,
|
||||
};
|
||||
}
|
||||
|
||||
/**
|
||||
* Hybrid search combining vector similarity and full-text search
|
||||
* Uses Reciprocal Rank Fusion (RRF) to combine rankings
|
||||
*
|
||||
* @param query - The search query string
|
||||
* @param workspaceId - The workspace to search within
|
||||
* @param options - Search options (status filter, pagination)
|
||||
* @returns Paginated search results ranked by combined relevance
|
||||
*/
|
||||
async hybridSearch(
|
||||
query: string,
|
||||
workspaceId: string,
|
||||
options: SearchOptions = {}
|
||||
): Promise<PaginatedSearchResults> {
|
||||
if (!this.embedding.isConfigured()) {
|
||||
// Fall back to keyword search if embeddings not configured
|
||||
return this.search(query, workspaceId, options);
|
||||
}
|
||||
|
||||
const page = options.page || 1;
|
||||
const limit = options.limit || 20;
|
||||
const offset = (page - 1) * limit;
|
||||
|
||||
// Sanitize query for keyword search
|
||||
const sanitizedQuery = this.sanitizeSearchQuery(query);
|
||||
|
||||
if (!sanitizedQuery) {
|
||||
return {
|
||||
data: [],
|
||||
pagination: {
|
||||
page,
|
||||
limit,
|
||||
total: 0,
|
||||
totalPages: 0,
|
||||
},
|
||||
query,
|
||||
};
|
||||
}
|
||||
|
||||
// Generate embedding for vector search
|
||||
const queryEmbedding = await this.embedding.generateEmbedding(query);
|
||||
const embeddingString = `[${queryEmbedding.join(",")}]`;
|
||||
|
||||
// Build status filter
|
||||
const statusFilter = options.status
|
||||
? Prisma.sql`AND e.status = ${options.status}::text::"EntryStatus"`
|
||||
: Prisma.sql`AND e.status != 'ARCHIVED'`;
|
||||
|
||||
// Hybrid search using Reciprocal Rank Fusion (RRF)
|
||||
// Combines vector similarity and full-text search rankings
|
||||
const searchResults = await this.prisma.$queryRaw<RawSearchResult[]>`
|
||||
WITH vector_search AS (
|
||||
SELECT
|
||||
e.id,
|
||||
ROW_NUMBER() OVER (ORDER BY emb.embedding <=> ${embeddingString}::vector) AS rank
|
||||
FROM knowledge_entries e
|
||||
INNER JOIN knowledge_embeddings emb ON e.id = emb.entry_id
|
||||
WHERE e.workspace_id = ${workspaceId}::uuid
|
||||
${statusFilter}
|
||||
),
|
||||
keyword_search AS (
|
||||
SELECT
|
||||
e.id,
|
||||
ROW_NUMBER() OVER (
|
||||
ORDER BY ts_rank(
|
||||
setweight(to_tsvector('english', e.title), 'A') ||
|
||||
setweight(to_tsvector('english', e.content), 'B'),
|
||||
plainto_tsquery('english', ${sanitizedQuery})
|
||||
) DESC
|
||||
) AS rank
|
||||
FROM knowledge_entries e
|
||||
WHERE e.workspace_id = ${workspaceId}::uuid
|
||||
${statusFilter}
|
||||
AND (
|
||||
to_tsvector('english', e.title) @@ plainto_tsquery('english', ${sanitizedQuery})
|
||||
OR to_tsvector('english', e.content) @@ plainto_tsquery('english', ${sanitizedQuery})
|
||||
)
|
||||
),
|
||||
combined AS (
|
||||
SELECT
|
||||
COALESCE(v.id, k.id) AS id,
|
||||
-- Reciprocal Rank Fusion: RRF(d) = sum(1 / (k + rank_i))
|
||||
-- k=60 is a common constant that prevents high rankings from dominating
|
||||
(COALESCE(1.0 / (60 + v.rank), 0) + COALESCE(1.0 / (60 + k.rank), 0)) AS rrf_score
|
||||
FROM vector_search v
|
||||
FULL OUTER JOIN keyword_search k ON v.id = k.id
|
||||
)
|
||||
SELECT
|
||||
e.id,
|
||||
e.workspace_id,
|
||||
e.slug,
|
||||
e.title,
|
||||
e.content,
|
||||
e.content_html,
|
||||
e.summary,
|
||||
e.status,
|
||||
e.visibility,
|
||||
e.created_at,
|
||||
e.updated_at,
|
||||
e.created_by,
|
||||
e.updated_by,
|
||||
c.rrf_score AS rank,
|
||||
ts_headline(
|
||||
'english',
|
||||
e.content,
|
||||
plainto_tsquery('english', ${sanitizedQuery}),
|
||||
'MaxWords=50, MinWords=25, StartSel=<mark>, StopSel=</mark>'
|
||||
) AS headline
|
||||
FROM combined c
|
||||
INNER JOIN knowledge_entries e ON c.id = e.id
|
||||
ORDER BY c.rrf_score DESC, e.updated_at DESC
|
||||
LIMIT ${limit}
|
||||
OFFSET ${offset}
|
||||
`;
|
||||
|
||||
// Get total count
|
||||
const countResult = await this.prisma.$queryRaw<[{ count: bigint }]>`
|
||||
WITH vector_search AS (
|
||||
SELECT e.id
|
||||
FROM knowledge_entries e
|
||||
INNER JOIN knowledge_embeddings emb ON e.id = emb.entry_id
|
||||
WHERE e.workspace_id = ${workspaceId}::uuid
|
||||
${statusFilter}
|
||||
),
|
||||
keyword_search AS (
|
||||
SELECT e.id
|
||||
FROM knowledge_entries e
|
||||
WHERE e.workspace_id = ${workspaceId}::uuid
|
||||
${statusFilter}
|
||||
AND (
|
||||
to_tsvector('english', e.title) @@ plainto_tsquery('english', ${sanitizedQuery})
|
||||
OR to_tsvector('english', e.content) @@ plainto_tsquery('english', ${sanitizedQuery})
|
||||
)
|
||||
)
|
||||
SELECT COUNT(DISTINCT id) as count
|
||||
FROM (
|
||||
SELECT id FROM vector_search
|
||||
UNION
|
||||
SELECT id FROM keyword_search
|
||||
) AS combined
|
||||
`;
|
||||
|
||||
const total = Number(countResult[0].count);
|
||||
|
||||
// Fetch tags for the results
|
||||
const entryIds = searchResults.map((r) => r.id);
|
||||
const tagsMap = await this.fetchTagsForEntries(entryIds);
|
||||
|
||||
// Transform results to the expected format
|
||||
const data: SearchResult[] = searchResults.map((row) => ({
|
||||
id: row.id,
|
||||
workspaceId: row.workspace_id,
|
||||
slug: row.slug,
|
||||
title: row.title,
|
||||
content: row.content,
|
||||
contentHtml: row.content_html,
|
||||
summary: row.summary,
|
||||
status: row.status,
|
||||
visibility: row.visibility as "PRIVATE" | "WORKSPACE" | "PUBLIC",
|
||||
createdAt: row.created_at,
|
||||
updatedAt: row.updated_at,
|
||||
createdBy: row.created_by,
|
||||
updatedBy: row.updated_by,
|
||||
rank: row.rank,
|
||||
headline: row.headline ?? undefined,
|
||||
tags: tagsMap.get(row.id) || [],
|
||||
}));
|
||||
|
||||
return {
|
||||
data,
|
||||
pagination: {
|
||||
page,
|
||||
limit,
|
||||
total,
|
||||
totalPages: Math.ceil(total / limit),
|
||||
},
|
||||
query,
|
||||
};
|
||||
}
|
||||
}
|
||||
|
||||
@@ -0,0 +1,257 @@
|
||||
import { describe, it, expect, beforeAll, afterAll } from "vitest";
|
||||
import { PrismaClient, EntryStatus } from "@prisma/client";
|
||||
import { SearchService } from "./search.service";
|
||||
import { EmbeddingService } from "./embedding.service";
|
||||
import { KnowledgeCacheService } from "./cache.service";
|
||||
import { PrismaService } from "../../prisma/prisma.service";
|
||||
|
||||
/**
|
||||
* Integration tests for semantic search functionality
|
||||
*
|
||||
* These tests require:
|
||||
* - A running PostgreSQL database with pgvector extension
|
||||
* - OPENAI_API_KEY environment variable set
|
||||
*
|
||||
* Run with: pnpm test semantic-search.integration.spec.ts
|
||||
*/
|
||||
describe("Semantic Search Integration", () => {
|
||||
let prisma: PrismaClient;
|
||||
let searchService: SearchService;
|
||||
let embeddingService: EmbeddingService;
|
||||
let cacheService: KnowledgeCacheService;
|
||||
let testWorkspaceId: string;
|
||||
let testUserId: string;
|
||||
|
||||
beforeAll(async () => {
|
||||
// Initialize services
|
||||
prisma = new PrismaClient();
|
||||
const prismaService = prisma as unknown as PrismaService;
|
||||
|
||||
// Mock cache service for testing
|
||||
cacheService = {
|
||||
getSearch: async () => null,
|
||||
setSearch: async () => {},
|
||||
isEnabled: () => false,
|
||||
getStats: () => ({ hits: 0, misses: 0, hitRate: 0 }),
|
||||
resetStats: () => {},
|
||||
} as unknown as KnowledgeCacheService;
|
||||
|
||||
embeddingService = new EmbeddingService(prismaService);
|
||||
searchService = new SearchService(
|
||||
prismaService,
|
||||
cacheService,
|
||||
embeddingService
|
||||
);
|
||||
|
||||
// Create test workspace and user
|
||||
const workspace = await prisma.workspace.create({
|
||||
data: {
|
||||
name: "Test Workspace for Semantic Search",
|
||||
owner: {
|
||||
create: {
|
||||
email: "semantic-test@example.com",
|
||||
name: "Test User",
|
||||
},
|
||||
},
|
||||
},
|
||||
});
|
||||
|
||||
testWorkspaceId = workspace.id;
|
||||
testUserId = workspace.ownerId;
|
||||
});
|
||||
|
||||
afterAll(async () => {
|
||||
// Cleanup test data
|
||||
if (testWorkspaceId) {
|
||||
await prisma.knowledgeEntry.deleteMany({
|
||||
where: { workspaceId: testWorkspaceId },
|
||||
});
|
||||
await prisma.workspace.delete({
|
||||
where: { id: testWorkspaceId },
|
||||
});
|
||||
}
|
||||
await prisma.$disconnect();
|
||||
});
|
||||
|
||||
describe("EmbeddingService", () => {
|
||||
it("should check if OpenAI is configured", () => {
|
||||
const isConfigured = embeddingService.isConfigured();
|
||||
// This test will pass if OPENAI_API_KEY is set
|
||||
expect(typeof isConfigured).toBe("boolean");
|
||||
});
|
||||
|
||||
it("should prepare content for embedding correctly", () => {
|
||||
const title = "Introduction to PostgreSQL";
|
||||
const content = "PostgreSQL is a powerful open-source database.";
|
||||
|
||||
const prepared = embeddingService.prepareContentForEmbedding(
|
||||
title,
|
||||
content
|
||||
);
|
||||
|
||||
// Title should appear twice for weighting
|
||||
expect(prepared).toContain(title);
|
||||
expect(prepared).toContain(content);
|
||||
const titleCount = (prepared.match(new RegExp(title, "g")) || []).length;
|
||||
expect(titleCount).toBe(2);
|
||||
});
|
||||
});
|
||||
|
||||
describe("Semantic Search", () => {
|
||||
const testEntries = [
|
||||
{
|
||||
slug: "postgresql-intro",
|
||||
title: "Introduction to PostgreSQL",
|
||||
content:
|
||||
"PostgreSQL is a powerful, open-source relational database system. It supports advanced data types and performance optimization features.",
|
||||
},
|
||||
{
|
||||
slug: "mongodb-basics",
|
||||
title: "MongoDB Basics",
|
||||
content:
|
||||
"MongoDB is a NoSQL document database. It stores data in flexible, JSON-like documents instead of tables and rows.",
|
||||
},
|
||||
{
|
||||
slug: "database-indexing",
|
||||
title: "Database Indexing Strategies",
|
||||
content:
|
||||
"Indexing is crucial for database performance. Both B-tree and hash indexes have their use cases depending on query patterns.",
|
||||
},
|
||||
];
|
||||
|
||||
it("should skip semantic search if OpenAI not configured", async () => {
|
||||
if (!embeddingService.isConfigured()) {
|
||||
await expect(
|
||||
searchService.semanticSearch(
|
||||
"database performance",
|
||||
testWorkspaceId
|
||||
)
|
||||
).rejects.toThrow();
|
||||
} else {
|
||||
// If configured, this is expected to work (tested below)
|
||||
expect(true).toBe(true);
|
||||
}
|
||||
});
|
||||
|
||||
it.skipIf(!process.env["OPENAI_API_KEY"])(
|
||||
"should generate embeddings and perform semantic search",
|
||||
async () => {
|
||||
// Create test entries
|
||||
for (const entry of testEntries) {
|
||||
const created = await prisma.knowledgeEntry.create({
|
||||
data: {
|
||||
workspaceId: testWorkspaceId,
|
||||
slug: entry.slug,
|
||||
title: entry.title,
|
||||
content: entry.content,
|
||||
status: EntryStatus.PUBLISHED,
|
||||
visibility: "WORKSPACE",
|
||||
createdBy: testUserId,
|
||||
updatedBy: testUserId,
|
||||
},
|
||||
});
|
||||
|
||||
// Generate embedding
|
||||
const preparedContent = embeddingService.prepareContentForEmbedding(
|
||||
entry.title,
|
||||
entry.content
|
||||
);
|
||||
await embeddingService.generateAndStoreEmbedding(
|
||||
created.id,
|
||||
preparedContent
|
||||
);
|
||||
}
|
||||
|
||||
// Wait a bit for embeddings to be stored
|
||||
await new Promise((resolve) => setTimeout(resolve, 1000));
|
||||
|
||||
// Perform semantic search
|
||||
const results = await searchService.semanticSearch(
|
||||
"relational database systems",
|
||||
testWorkspaceId
|
||||
);
|
||||
|
||||
// Should return results
|
||||
expect(results.data.length).toBeGreaterThan(0);
|
||||
|
||||
// PostgreSQL entry should rank high for "relational database"
|
||||
const postgresEntry = results.data.find(
|
||||
(r) => r.slug === "postgresql-intro"
|
||||
);
|
||||
expect(postgresEntry).toBeDefined();
|
||||
expect(postgresEntry!.rank).toBeGreaterThan(0);
|
||||
},
|
||||
30000 // 30 second timeout for API calls
|
||||
);
|
||||
|
||||
it.skipIf(!process.env["OPENAI_API_KEY"])(
|
||||
"should perform hybrid search combining vector and keyword",
|
||||
async () => {
|
||||
const results = await searchService.hybridSearch(
|
||||
"indexing",
|
||||
testWorkspaceId
|
||||
);
|
||||
|
||||
// Should return results
|
||||
expect(results.data.length).toBeGreaterThan(0);
|
||||
|
||||
// Should find the indexing entry
|
||||
const indexingEntry = results.data.find(
|
||||
(r) => r.slug === "database-indexing"
|
||||
);
|
||||
expect(indexingEntry).toBeDefined();
|
||||
},
|
||||
30000
|
||||
);
|
||||
});
|
||||
|
||||
describe("Batch Embedding Generation", () => {
|
||||
it.skipIf(!process.env["OPENAI_API_KEY"])(
|
||||
"should batch generate embeddings",
|
||||
async () => {
|
||||
// Create entries without embeddings
|
||||
const entries = await Promise.all(
|
||||
Array.from({ length: 3 }, (_, i) =>
|
||||
prisma.knowledgeEntry.create({
|
||||
data: {
|
||||
workspaceId: testWorkspaceId,
|
||||
slug: `batch-test-${i}`,
|
||||
title: `Batch Test Entry ${i}`,
|
||||
content: `This is test content for batch entry ${i}`,
|
||||
status: EntryStatus.PUBLISHED,
|
||||
visibility: "WORKSPACE",
|
||||
createdBy: testUserId,
|
||||
updatedBy: testUserId,
|
||||
},
|
||||
})
|
||||
)
|
||||
);
|
||||
|
||||
// Batch generate embeddings
|
||||
const entriesForEmbedding = entries.map((e) => ({
|
||||
id: e.id,
|
||||
content: embeddingService.prepareContentForEmbedding(
|
||||
e.title,
|
||||
e.content
|
||||
),
|
||||
}));
|
||||
|
||||
const successCount = await embeddingService.batchGenerateEmbeddings(
|
||||
entriesForEmbedding
|
||||
);
|
||||
|
||||
expect(successCount).toBe(3);
|
||||
|
||||
// Verify embeddings were created
|
||||
const embeddings = await prisma.knowledgeEmbedding.findMany({
|
||||
where: {
|
||||
entryId: { in: entries.map((e) => e.id) },
|
||||
},
|
||||
});
|
||||
|
||||
expect(embeddings.length).toBe(3);
|
||||
},
|
||||
60000 // 60 second timeout for batch operations
|
||||
);
|
||||
});
|
||||
});
|
||||
346
docs/SEMANTIC_SEARCH.md
Normal file
346
docs/SEMANTIC_SEARCH.md
Normal file
@@ -0,0 +1,346 @@
|
||||
# Semantic Search Implementation
|
||||
|
||||
This document describes the semantic search implementation for the Mosaic Stack Knowledge Module using OpenAI embeddings and PostgreSQL pgvector.
|
||||
|
||||
## Overview
|
||||
|
||||
The semantic search feature enables AI-powered similarity search across knowledge entries using vector embeddings. It complements the existing full-text search with semantic understanding, allowing users to find relevant content even when exact keywords don't match.
|
||||
|
||||
## Architecture
|
||||
|
||||
### Components
|
||||
|
||||
1. **EmbeddingService** - Generates and manages OpenAI embeddings
|
||||
2. **SearchService** - Enhanced with semantic and hybrid search methods
|
||||
3. **KnowledgeService** - Automatically generates embeddings on entry create/update
|
||||
4. **pgvector** - PostgreSQL extension for vector similarity search
|
||||
|
||||
### Database Schema
|
||||
|
||||
#### Knowledge Embeddings Table
|
||||
|
||||
```prisma
|
||||
model KnowledgeEmbedding {
|
||||
id String @id @default(uuid()) @db.Uuid
|
||||
entryId String @unique @map("entry_id") @db.Uuid
|
||||
entry KnowledgeEntry @relation(fields: [entryId], references: [id], onDelete: Cascade)
|
||||
|
||||
embedding Unsupported("vector(1536)")
|
||||
model String
|
||||
|
||||
createdAt DateTime @default(now()) @map("created_at") @db.Timestamptz
|
||||
updatedAt DateTime @updatedAt @map("updated_at") @db.Timestamptz
|
||||
|
||||
@@index([entryId])
|
||||
@@map("knowledge_embeddings")
|
||||
}
|
||||
```
|
||||
|
||||
#### Vector Index
|
||||
|
||||
An HNSW (Hierarchical Navigable Small World) index is created for fast similarity search:
|
||||
|
||||
```sql
|
||||
CREATE INDEX knowledge_embeddings_embedding_idx
|
||||
ON knowledge_embeddings
|
||||
USING hnsw (embedding vector_cosine_ops)
|
||||
WITH (m = 16, ef_construction = 64);
|
||||
```
|
||||
|
||||
## Configuration
|
||||
|
||||
### Environment Variables
|
||||
|
||||
Add to your `.env` file:
|
||||
|
||||
```env
|
||||
# Optional: Required for semantic search
|
||||
OPENAI_API_KEY=sk-...
|
||||
```
|
||||
|
||||
Get your API key from: https://platform.openai.com/api-keys
|
||||
|
||||
### OpenAI Model
|
||||
|
||||
The default embedding model is `text-embedding-3-small` (1536 dimensions). This provides:
|
||||
- High quality embeddings
|
||||
- Cost-effective pricing
|
||||
- Fast generation speed
|
||||
|
||||
## API Endpoints
|
||||
|
||||
### 1. Semantic Search
|
||||
|
||||
**POST** `/api/knowledge/search/semantic`
|
||||
|
||||
Search using vector similarity only.
|
||||
|
||||
**Request:**
|
||||
```json
|
||||
{
|
||||
"query": "database performance optimization",
|
||||
"status": "PUBLISHED"
|
||||
}
|
||||
```
|
||||
|
||||
**Query Parameters:**
|
||||
- `page` (optional): Page number (default: 1)
|
||||
- `limit` (optional): Results per page (default: 20)
|
||||
|
||||
**Response:**
|
||||
```json
|
||||
{
|
||||
"data": [
|
||||
{
|
||||
"id": "uuid",
|
||||
"slug": "postgres-indexing",
|
||||
"title": "PostgreSQL Indexing Strategies",
|
||||
"content": "...",
|
||||
"rank": 0.87,
|
||||
"tags": [...],
|
||||
...
|
||||
}
|
||||
],
|
||||
"pagination": {
|
||||
"page": 1,
|
||||
"limit": 20,
|
||||
"total": 15,
|
||||
"totalPages": 1
|
||||
},
|
||||
"query": "database performance optimization"
|
||||
}
|
||||
```
|
||||
|
||||
### 2. Hybrid Search (Recommended)
|
||||
|
||||
**POST** `/api/knowledge/search/hybrid`
|
||||
|
||||
Combines vector similarity and full-text search using Reciprocal Rank Fusion (RRF).
|
||||
|
||||
**Request:**
|
||||
```json
|
||||
{
|
||||
"query": "indexing strategies",
|
||||
"status": "PUBLISHED"
|
||||
}
|
||||
```
|
||||
|
||||
**Benefits of Hybrid Search:**
|
||||
- Best of both worlds: semantic understanding + keyword matching
|
||||
- Better ranking for exact matches
|
||||
- Improved recall and precision
|
||||
- Resilient to edge cases
|
||||
|
||||
### 3. Batch Embedding Generation
|
||||
|
||||
**POST** `/api/knowledge/embeddings/batch`
|
||||
|
||||
Generate embeddings for all existing entries. Useful for:
|
||||
- Initial setup after enabling semantic search
|
||||
- Regenerating embeddings after model updates
|
||||
|
||||
**Request:**
|
||||
```json
|
||||
{
|
||||
"status": "PUBLISHED"
|
||||
}
|
||||
```
|
||||
|
||||
**Response:**
|
||||
```json
|
||||
{
|
||||
"message": "Generated 42 embeddings out of 45 entries",
|
||||
"total": 45,
|
||||
"success": 42
|
||||
}
|
||||
```
|
||||
|
||||
**Permissions:** Requires ADMIN role
|
||||
|
||||
## Automatic Embedding Generation
|
||||
|
||||
Embeddings are automatically generated when:
|
||||
|
||||
1. **Creating an entry** - Embedding generated asynchronously after creation
|
||||
2. **Updating an entry** - Embedding regenerated if title or content changes
|
||||
|
||||
The generation happens asynchronously to avoid blocking API responses.
|
||||
|
||||
### Content Preparation
|
||||
|
||||
Before generating embeddings, content is prepared by:
|
||||
1. Combining title and content
|
||||
2. Weighting title more heavily (appears twice)
|
||||
3. This improves semantic matching on titles
|
||||
|
||||
```typescript
|
||||
prepareContentForEmbedding(title, content) {
|
||||
return `${title}\n\n${title}\n\n${content}`.trim();
|
||||
}
|
||||
```
|
||||
|
||||
## Search Algorithms
|
||||
|
||||
### Vector Similarity Search
|
||||
|
||||
Uses cosine distance to find semantically similar entries:
|
||||
|
||||
```sql
|
||||
SELECT *
|
||||
FROM knowledge_entries e
|
||||
INNER JOIN knowledge_embeddings emb ON e.id = emb.entry_id
|
||||
ORDER BY emb.embedding <=> query_embedding
|
||||
LIMIT 20
|
||||
```
|
||||
|
||||
- `<=>` operator: cosine distance
|
||||
- Lower distance = higher similarity
|
||||
- Efficient with HNSW index
|
||||
|
||||
### Hybrid Search (RRF Algorithm)
|
||||
|
||||
Reciprocal Rank Fusion combines rankings from multiple sources:
|
||||
|
||||
```
|
||||
RRF(d) = sum(1 / (k + rank_i))
|
||||
```
|
||||
|
||||
Where:
|
||||
- `d` = document
|
||||
- `k` = constant (60 is standard)
|
||||
- `rank_i` = rank from source i
|
||||
|
||||
**Example:**
|
||||
|
||||
Document ranks in two searches:
|
||||
- Vector search: rank 3
|
||||
- Keyword search: rank 1
|
||||
|
||||
RRF score = 1/(60+3) + 1/(60+1) = 0.0159 + 0.0164 = 0.0323
|
||||
|
||||
Higher RRF score = better combined ranking.
|
||||
|
||||
## Performance Considerations
|
||||
|
||||
### Index Parameters
|
||||
|
||||
The HNSW index uses:
|
||||
- `m = 16`: Max connections per layer (balances accuracy/memory)
|
||||
- `ef_construction = 64`: Build quality (higher = more accurate, slower build)
|
||||
|
||||
### Query Performance
|
||||
|
||||
- **Typical query time:** 10-50ms (with index)
|
||||
- **Without index:** 1000ms+ (not recommended)
|
||||
- **Embedding generation:** 100-300ms per entry
|
||||
|
||||
### Cost (OpenAI API)
|
||||
|
||||
Using `text-embedding-3-small`:
|
||||
- ~$0.00002 per 1000 tokens
|
||||
- Average entry (~500 tokens): $0.00001
|
||||
- 10,000 entries: ~$0.10
|
||||
|
||||
Very cost-effective for most use cases.
|
||||
|
||||
## Migration Guide
|
||||
|
||||
### 1. Run Migrations
|
||||
|
||||
```bash
|
||||
cd apps/api
|
||||
pnpm prisma migrate deploy
|
||||
```
|
||||
|
||||
This creates:
|
||||
- `knowledge_embeddings` table
|
||||
- Vector index on embeddings
|
||||
|
||||
### 2. Configure OpenAI API Key
|
||||
|
||||
```bash
|
||||
# Add to .env
|
||||
OPENAI_API_KEY=sk-...
|
||||
```
|
||||
|
||||
### 3. Generate Embeddings for Existing Entries
|
||||
|
||||
```bash
|
||||
curl -X POST http://localhost:3001/api/knowledge/embeddings/batch \
|
||||
-H "Authorization: Bearer YOUR_TOKEN" \
|
||||
-H "Content-Type: application/json" \
|
||||
-d '{"status": "PUBLISHED"}'
|
||||
```
|
||||
|
||||
Or use the web UI (Admin dashboard → Knowledge → Generate Embeddings).
|
||||
|
||||
### 4. Test Semantic Search
|
||||
|
||||
```bash
|
||||
curl -X POST http://localhost:3001/api/knowledge/search/hybrid \
|
||||
-H "Authorization: Bearer YOUR_TOKEN" \
|
||||
-H "Content-Type: application/json" \
|
||||
-d '{"query": "your search query"}'
|
||||
```
|
||||
|
||||
## Troubleshooting
|
||||
|
||||
### "OpenAI API key not configured"
|
||||
|
||||
**Cause:** `OPENAI_API_KEY` environment variable not set
|
||||
|
||||
**Solution:** Add the API key to your `.env` file and restart the API server
|
||||
|
||||
### Semantic search returns no results
|
||||
|
||||
**Possible causes:**
|
||||
|
||||
1. **No embeddings generated**
|
||||
- Run batch generation endpoint
|
||||
- Check `knowledge_embeddings` table
|
||||
|
||||
2. **Query too specific**
|
||||
- Try broader terms
|
||||
- Use hybrid search for better recall
|
||||
|
||||
3. **Index not created**
|
||||
- Check migration status
|
||||
- Verify index exists: `\di knowledge_embeddings_embedding_idx` in psql
|
||||
|
||||
### Slow query performance
|
||||
|
||||
**Solutions:**
|
||||
|
||||
1. Verify index exists and is being used:
|
||||
```sql
|
||||
EXPLAIN ANALYZE
|
||||
SELECT * FROM knowledge_embeddings
|
||||
ORDER BY embedding <=> '[...]'::vector
|
||||
LIMIT 20;
|
||||
```
|
||||
|
||||
2. Adjust index parameters (requires recreation):
|
||||
```sql
|
||||
DROP INDEX knowledge_embeddings_embedding_idx;
|
||||
CREATE INDEX knowledge_embeddings_embedding_idx
|
||||
ON knowledge_embeddings
|
||||
USING hnsw (embedding vector_cosine_ops)
|
||||
WITH (m = 32, ef_construction = 128); -- Higher values
|
||||
```
|
||||
|
||||
## Future Enhancements
|
||||
|
||||
Potential improvements:
|
||||
|
||||
1. **Custom embeddings**: Support for local embedding models (Ollama, etc.)
|
||||
2. **Chunking**: Split large entries into chunks for better granularity
|
||||
3. **Reranking**: Add cross-encoder reranking for top results
|
||||
4. **Caching**: Cache query embeddings for repeated searches
|
||||
5. **Multi-modal**: Support image/file embeddings
|
||||
|
||||
## References
|
||||
|
||||
- [OpenAI Embeddings Guide](https://platform.openai.com/docs/guides/embeddings)
|
||||
- [pgvector Documentation](https://github.com/pgvector/pgvector)
|
||||
- [HNSW Algorithm Paper](https://arxiv.org/abs/1603.09320)
|
||||
- [Reciprocal Rank Fusion](https://plg.uwaterloo.ca/~gvcormac/cormacksigir09-rrf.pdf)
|
||||
20
pnpm-lock.yaml
generated
20
pnpm-lock.yaml
generated
@@ -113,6 +113,9 @@ importers:
|
||||
ollama:
|
||||
specifier: ^0.6.3
|
||||
version: 0.6.3
|
||||
openai:
|
||||
specifier: ^6.17.0
|
||||
version: 6.17.0(ws@8.19.0)(zod@4.3.6)
|
||||
reflect-metadata:
|
||||
specifier: ^0.2.2
|
||||
version: 0.2.2
|
||||
@@ -4076,6 +4079,18 @@ packages:
|
||||
resolution: {integrity: sha512-YgBpdJHPyQ2UE5x+hlSXcnejzAvD0b22U2OuAP+8OnlJT+PjWPxtgmGqKKc+RgTM63U9gN0YzrYc71R2WT/hTA==}
|
||||
engines: {node: '>=18'}
|
||||
|
||||
openai@6.17.0:
|
||||
resolution: {integrity: sha512-NHRpPEUPzAvFOAFs9+9pC6+HCw/iWsYsKCMPXH5Kw7BpMxqd8g/A07/1o7Gx2TWtCnzevVRyKMRFqyiHyAlqcA==}
|
||||
hasBin: true
|
||||
peerDependencies:
|
||||
ws: ^8.18.0
|
||||
zod: ^3.25 || ^4.0
|
||||
peerDependenciesMeta:
|
||||
ws:
|
||||
optional: true
|
||||
zod:
|
||||
optional: true
|
||||
|
||||
optionator@0.9.4:
|
||||
resolution: {integrity: sha512-6IpQ7mKUxRcZNLIObR0hz7lxsapSSIYNZJwXPGeF0mTVqGKFIXj1DQcMoT22S3ROcLyY/rz0PWaWZ9ayWmad9g==}
|
||||
engines: {node: '>= 0.8.0'}
|
||||
@@ -9134,6 +9149,11 @@ snapshots:
|
||||
is-inside-container: 1.0.0
|
||||
wsl-utils: 0.1.0
|
||||
|
||||
openai@6.17.0(ws@8.19.0)(zod@4.3.6):
|
||||
optionalDependencies:
|
||||
ws: 8.19.0
|
||||
zod: 4.3.6
|
||||
|
||||
optionator@0.9.4:
|
||||
dependencies:
|
||||
deep-is: 0.1.4
|
||||
|
||||
Reference in New Issue
Block a user