API integration for Google Drive
We build your Google Drive connector
We link your business file to the Google Drive API to deposit, export and react to a file, with drive.file plus Picker rather than a restricted scope.
- Senior product team
- Drive connectors in production
- from scoping to monitoring
What does the Google Drive API provide and why integrate it into business software?
Google Drive is the reference file storage system for millions of companies working in the Google Workspace ecosystem. Its API lets your application deposit files into a specific Drive, listen for document additions or changes and process them automatically, and export Sheets or Docs to your software. You integrate it so that quotes, contracts or reports generated by your application are automatically saved in the client's Drive folder, without teams switching between tools.
What our clients build on the Google Drive API
Portal with Picker, not the whole Drive
The user picks the file. drive.file is enough. No six-month security assessment for a document drop.
Deal folder in a shared drive
Folder create, PDFs pushed, reaction to a signed contract dropped by sales. My Drive alone misses the real IS.
Accounting export from Sheets
files.export as CSV or PDF into the ERP. The table stays a Google Doc, the business flow receives a readable file.
"Inbox" folder under files.watch
X-Goog-Changed (content, permissions, parents) steers the re-read. A dropped PDF creates the deal, with no polling.
What this changes in your Workspace files
The engineering serves a measurable result: the document in the file, a signable scope, fewer dead links.
You do not ask for the whole Drive
The user picks the file in the picker. That is often the only path compatible with a production timeline.
Docs and Sheets become usable
Export to PDF or CSV is part of the connector. A download everything without native export misses the core of the Google estate.
Shared drives are the system of record
We target the team drive in scoping. A My Drive demo that fails at the customer is not what we ship.
Quota does not kill the journey
Reads are paced. A naive crawl burns the user quota long before the project limit.
How we deliver your Google Drive connector
Scoping
drive.file or a restricted scope (eligibility, audit), Picker, shared drives, Docs export. We refuse "we sync everything" without a security dossier.
Development
Persisted startPageToken, renewed watch, 5/50/100/200 unit counter, resumable upload beyond 5 MB, export and shortcut branches.
Acceptance
Doc vs PDF, shared drive without supportsAllDrives, expired channel, rejected changes token, 750 GB/day. Replay before cutover.
Monitoring
Alert on 403/429, dead channel, units/minute. Revocation procedure when the client leaves. Refresh tokens encrypted off-repo.
What the Google Drive API allows
- Files, folders, shared drives
- files, drives, permissions, revisions. Shortcuts and folders have no binary. appDataFolder for application state invisible in the UI.
- Three upload modes
- media and multipart up to 5 MB. resumable beyond that, or as soon as a drop is likely. The session URI expires after one week.
- Export of Google files
- files.export to a MIME type. alt=media does not download a Doc as a PDF. This is the branch that separates a Workspace connector from a files tutorial.
- changes journal and push
- getStartPageToken then changes.list. watch on a file or on the journal (pageToken required). Empty body, X-Goog-Changed sometimes present on files.watch.
Google Drive API vocabulary
- drive.file
- Non-sensitive scope: only files the app opened or created. Coupled with Picker, this is the production path. drive and drive.readonly are restricted.
- startPageToken
- Cursor of the changes journal. We persist newStartPageToken. A rejected token forces a full replay, like a Calendar 410.
- X-Goog-Changed
- On files.watch: content, properties, parents, children, permissions. On changes.watch, the state is change: you must re-read the journal. Body always empty.
- files.export
- Only way out of a Doc/Sheet/Slide. alt=media does not apply to Google types. Export MIME scoped per project (PDF, CSV, DOCX).
- Units
- Read 5, edit 50, list 100, download 200. This is no longer "requests per second". 750 GB upload/day/Workspace user, max file 5 TB.
- supportsAllDrives
- Required as soon as a shared drive is in play, with driveId / corpora / includeItemsFromAllDrives. Forgetting it is a My Drive demo.
The real constraints of the Google Drive API
Wide scopes are restricted
drive, drive.readonly, metadata, activity: security assessment if you store or transmit outside Google, and only eligible app categories. Promising "the whole Drive" without that budget stops the project at OAuth consent.
The notification is empty
Same family as Calendar. No HMAC. Handler: validate the token, enqueue, 2xx. Re-read via changes.list. No automatic channel renewal.
Listing is expensive
files.list = 20 × files.get. A recursive crawl burns 325,000 units/min/user. fields=* in production is an anti-pattern. Truncated backoff per the Google limits guide.
quotaUser does not save authenticated Drive
For Drive with a token, quota follows the token, not quotaUser (reserved to anonymous on public files). A delegated service account remains one user. 2026 billing to price into the TCO.
Google Drive API or SharePoint API?
Two corporate disks. The right one follows Workspace or the Microsoft tenant already there.
| Criterion | Google DriveThis page | Microsoft 365Graph files |
|---|---|---|
| Typical estate | Workspace, shared drives | SharePoint / OneDrive on the tenant |
| Fine perimeter | drive.file + Picker | Sites.Selected + POST /permissions |
| Office files | MIME export required (Docs/Sheets) | binaries and Office in the drive |
| Increment | changes.list + startPageToken | delta query + deltaLink |
| Push signature | No HMAC, channel token | Graph subscription, 202 first |
| Resumable upload | from 5 MB, URI 7 days | from ~10 MiB, multiples of 320 KiB |
| The right case | The company is already on Workspace | The company is already on Microsoft 365 |
Box and Dropbox come up if the DMS is neither Drive nor SharePoint. Sheets is a deliverable only if the table really is the document.
What we measure on a Google Drive integration
The other file APIs
If the estate is not Workspace, these options belong in the scoping conversation.
Google DriveWe build your Google Drive connectorThis page
Microsoft 365SharePoint and OneDrive via Graph, Sites.Selected.
BoxEnterprise DMS, HMAC webhooks, App Users.
DropboxFile sharing, list_folder cursor, App Folder.We combine Google Drive with
The stack around Drive on our projects.
Google Drive integration: your questions
OAuth with the narrowest possible scope (drive.file plus Picker by default), a client that sends fields, an export branch for Google types, resumable upload beyond 5 MB, changes journal plus watch for near real time. supportsAllDrives as soon as a shared drive exists. A unit counter on the client. The hard part is not files.create, it is the restricted scope we did not promise, and a push channel with no HMAC.
The healthy default is drive.file, non-sensitive, limited to the app's files, glued to Picker. drive.appdata is for application state. drive and drive.readonly are restricted: security assessment, eligible app categories (backup, productivity, reporting). Promising a full sync without that dossier is a project stopped at consent. Google also pushes migration toward drive.file. This is a scoping call, written down before the first request, not an acceptance surprise.
A first useful flow, typically a Picker drop attached to the business file, ships in two to three weeks. A DMS connector (changes, watch, export, shared drives, unit counter) is closer to six to eight weeks. A restricted scope adds Google's audit calendar, often longer than the code. We say so at scoping. This is a scoping call, written down before the first request, not an acceptance surprise. A restricted scope adds Google's security assessment calendar, often longer than the code itself.
Follow the tenant. Workspace: Drive v3. Microsoft 365: Graph files (Microsoft 365 page). Both have an increment and a push that needs a re-read. Drive requires files.export for Docs/Sheets; SharePoint speaks units and Sites.Selected. Box and Dropbox if the DMS is already elsewhere. This is a scoping call, written down before the first request, not an acceptance surprise. Box and Dropbox come up if the DMS already lives somewhere else.
Not with files.get alt=media. A Doc, Sheet or Slide comes out through files.export to a MIME type (PDF, DOCX, CSV, and so on). Shortcuts are followed via shortcutDetails.targetId. Folders have no binary content. A connector that "downloads everything" without this branch is wrong on the Workspace estate, even if the demo passes on a PDF. This is a scoping call, written down before the first request, not an acceptance surprise.
A Google Drive integration project?
Let's talk. 30 minutes to scope Picker, scopes, shared drives, and tell you plainly if a restricted scope is tenable.
Discuss my Drive project