> ## Documentation Index > Fetch the complete documentation index at: https://docs.insforge.dev/llms.txt > Use this file to discover all available pages before exploring further. # Get Upload Strategy (Direct or Presigned URL) > Returns the upload strategy for the requested object. Local storage always returns direct upload endpoints. S3 storage may return either `presigned` or `direct` strategies depending on the `S3_USE_PRESIGNED_URLS` configuration. Clients must determine the upload flow from the returned response, using the method field, rather than assuming behavior based on the configured storage backend. The filename is used verbatim as the object key. Uploading to an existing key replaces the current object in place. To upload with a server-generated unique key instead, use `POST /api/storage/buckets/{bucketName}/objects`. End-user creates and replacements are gated by the `storage.objects` row-level-security policies. ## OpenAPI ````yaml https://raw.githubusercontent.com/InsForge/InsForge/main/openapi/storage.yaml post /api/storage/buckets/{bucketName}/upload-strategy openapi: 3.0.3 info: title: Insforge Storage API version: 2.0.0 description: Bucket-based storage system similar to S3 servers: [] security: [] paths: /api/storage/buckets/{bucketName}/upload-strategy: post: tags: - Client summary: Get Upload Strategy (Direct or Presigned URL) description: > Returns the upload strategy for the requested object. Local storage always returns direct upload endpoints. S3 storage may return either `presigned` or `direct` strategies depending on the `S3_USE_PRESIGNED_URLS` configuration. Clients must determine the upload flow from the returned response, using the method field, rather than assuming behavior based on the configured storage backend. The filename is used verbatim as the object key. Uploading to an existing key replaces the current object in place. To upload with a server-generated unique key instead, use `POST /api/storage/buckets/{bucketName}/objects`. End-user creates and replacements are gated by the `storage.objects` row-level-security policies. parameters: - name: bucketName in: path required: true schema: type: string pattern: ^[a-zA-Z0-9_-]+$ example: avatars requestBody: required: true content: application/json: schema: type: object required: - filename properties: filename: type: string description: Object key to upload to (used verbatim) example: profile-photo.jpg contentType: type: string example: image/jpeg description: MIME type of the file size: type: integer description: File size in bytes example: 102400 responses: '200': description: Upload strategy details content: application/json: schema: $ref: '#/components/schemas/UploadStrategy' examples: s3: summary: S3 Backend Response value: method: presigned uploadUrl: https://s3-bucket.amazonaws.com/ fields: bucket: my-s3-bucket key: app-key/avatars/profile-photo.jpg X-Amz-Algorithm: AWS4-HMAC-SHA256 X-Amz-Credential: AKIA.../20250905/us-east-2/s3/aws4_request X-Amz-Date: 20250905T000000Z Policy: eyJ... X-Amz-Signature: abc123... key: profile-photo.jpg confirmRequired: true confirmUrl: >- /api/storage/buckets/avatars/objects/profile-photo.jpg/confirm-upload expiresAt: '2025-09-05T01:00:00Z' s3Proxy: summary: S3 Backend (Proxy Mode) value: method: direct uploadUrl: /api/storage/buckets/avatars/objects/profile-photo.jpg key: profile-photo.jpg confirmRequired: false local: summary: Local Storage Response value: method: direct uploadUrl: /api/storage/buckets/avatars/objects/profile-photo.jpg key: profile-photo.jpg confirmRequired: false '403': description: The caller is not permitted to create or replace this object content: application/json: schema: $ref: '#/components/schemas/ErrorResponse' example: error: STORAGE_PERMISSION_DENIED message: >- You do not have permission to replace "profile-photo.jpg" in bucket "avatars" statusCode: 403 '404': description: Bucket not found content: application/json: schema: $ref: '#/components/schemas/ErrorResponse' security: - apiKey: [] components: schemas: UploadStrategy: type: object required: - method - uploadUrl - key - confirmRequired properties: method: type: string enum: - presigned - direct description: >- Upload method. `presigned` is returned when S3 presigned URLs are enabled; `direct` is returned for local storage and S3 proxy mode. example: presigned uploadUrl: type: string description: URL to upload the file to example: https://s3-bucket.amazonaws.com/ fields: type: object description: Form fields for presigned POST (S3 only) additionalProperties: true example: bucket: my-s3-bucket key: app-key/avatars/profile.jpg X-Amz-Algorithm: AWS4-HMAC-SHA256 key: type: string description: Final logical object key (the filename, used verbatim). example: profile-photo.jpg confirmRequired: type: boolean description: >- Whether the upload must be confirmed after completion. When `false`, clients must not call the confirm upload endpoint. example: true confirmUrl: type: string description: >- Upload confirmation endpoint. Present only when `confirmRequired` is `true`. example: /api/storage/buckets/avatars/objects/profile.jpg/confirm-upload expiresAt: type: string format: date-time description: Expiration time for presigned URL (S3 only) example: '2025-09-05T01:00:00Z' ErrorResponse: type: object required: - error - message - statusCode properties: error: type: string description: Error code for programmatic handling example: VALIDATION_ERROR message: type: string description: Human-readable error message example: Invalid request statusCode: type: integer description: HTTP status code example: 400 nextActions: type: string description: Suggested action to resolve the error example: Check your request parameters securitySchemes: apiKey: type: apiKey in: header name: x-api-key ````