Glean Upgrade & Migration

Overview

Glean is an enterprise search platform that indexes documents across SaaS tools via connectors and exposes Search and Indexing APIs. Migrations involve connector schema changes, search API response format updates, and document permission model upgrades. Tracking API versions is critical because Glean's Indexing API enforces document schema validation — adding required fields or changing permission structures in a new version will cause bulk indexing failures and stale search results if connectors are not updated in lockstep.

Version Detection

const GLEAN_BASE = "https://your-domain-be.glean.com/api";

async function detectGleanApiVersion(apiToken: string): Promise<void> {
  // Check indexing API health and version
  const indexRes = await fetch(`${GLEAN_BASE}/index/v1/status`, {
    headers: { Authorization: `Bearer ${apiToken}`, "Content-Type": "application/json" },
  });
  const indexStatus = await indexRes.json();
  console.log(`Indexing API version: ${indexRes.headers.get("x-glean-api-version") ?? "v1"}`);
  console.log(`Connector status: ${JSON.stringify(indexStatus.connectors)}`);

  // Check search API for deprecated query parameters
  const searchRes = await fetch(`${GLEAN_BASE}/client/v1/search`, {
    method: "POST",
    headers: { Authorization: `Bearer ${apiToken}`, "Content-Type": "application/json" },
    body: JSON.stringify({ query: "test", pageSize: 1 }),
  });
  const deprecationHeader = searchRes.headers.get("x-glean-deprecated-params");
  if (deprecationHeader) console.warn(`Deprecated parameters: ${deprecationHeader}`);
}

Migration Checklist

Review Glean developer changelog for Indexing API schema changes
Audit custom connectors for deprecated document fields
Verify
```
objectType
```
definitions match current Glean schema requirements
Check if new required fields were added to document permission model
Test search API response parsing —
```
results[].snippets
```
format may change
Update datasource configuration if connector authentication method changed
Validate bulk indexing with a small document batch before full re-index
Check
```
people
```
API for identity resolution field changes
Update search query syntax if faceted search operators were modified
Monitor indexing error dashboard for 48 hours post-migration

Schema Migration

// Glean document schema evolved: flat permissions → structured ACL model
interface OldGleanDocument {
  id: string;
  datasource: string;
  title: string;
  body: { mimeType: string; textContent: string };
  permissions: { allowedUsers: string[] };
  updatedAt: string;
}

interface NewGleanDocument {
  id: string;
  datasource: string;
  title: string;
  body: { mimeType: string; textContent: string };
  permissions: {
    allowedUsers: Array<{ email: string; datasourceUserId?: string }>;
    allowedGroups: Array<{ name: string; datasourceGroupId?: string }>;
    allowAnonymousAccess: boolean;
  };
  viewURL: string;
  updatedAt: string;
}

function migrateDocument(old: OldGleanDocument): NewGleanDocument {
  return {
    ...old,
    permissions: {
      allowedUsers: old.permissions.allowedUsers.map((email) => ({ email })),
      allowedGroups: [],
      allowAnonymousAccess: false,
    },
    viewURL: `https://app.example.com/doc/${old.id}`,
  };
}

Rollback Strategy

class GleanIndexClient {
  constructor(
    private token: string,
    private baseUrl: string,
    private apiVersion: "v1" | "v2" = "v2"
  ) {}

  async indexDocuments(docs: any[]): Promise<any> {
    try {
      const res = await fetch(`${this.baseUrl}/index/${this.apiVersion}/indexdocuments`, {
        method: "POST",
        headers: { Authorization: `Bearer ${this.token}`, "Content-Type": "application/json" },
        body: JSON.stringify({ documents: docs }),
      });
      if (!res.ok) throw new Error(`Glean indexing ${res.status}: ${await res.text()}`);
      return await res.json();
    } catch (err) {
      if (this.apiVersion === "v2") {
        console.warn("Falling back to Glean Indexing API v1");
        this.apiVersion = "v1";
        return this.indexDocuments(docs);
      }
      throw err;
    }
  }
}

Error Handling

Migration Issue	Symptom	Fix
Document schema validation failure	`400` with `missing required field: viewURL`	Add `viewURL` to all documents before re-indexing
Permission model mismatch	Documents indexed but not searchable by expected users	Migrate flat `allowedUsers` strings to structured user objects
Connector auth expired	`401 Unauthorized` on bulk index	Rotate API token in Glean admin and update connector config
Search response format changed	Client crashes parsing `snippets` as string instead of array	Handle both `string` and `Snippet[]` return types
Datasource quota exceeded	`429` during bulk re-index	Implement rate limiting with exponential backoff per Glean docs

Resources

Next Steps

For CI pipeline integration, see

glean-ci-integration

Claude-code-plugins-plus-skills glean-upgrade-migration