Importing OpenAPI Specs
Import Methods
Import an OpenAPI or Swagger specification to create a new project. All endpoints, schemas, and security configurations are converted automatically.
From URL
Enter a URL to a hosted spec file
Upload File
Select a local .json, .yaml, or .yml file
Paste Content
Paste YAML or JSON directly
How to Import
Open New Project Dialog
Click "New Project" in the Projects section of the sidebar.
Select "Import OpenAPI" Tab
Switch from "From Scratch" to "Import OpenAPI".
Choose Import Method
Select URL, File, or Paste and provide your spec.
Click "Import & Open"
Tigrister parses the spec, creates the project, and opens the Designer.
Enter a URL to a JSON or YAML OpenAPI spec
What Gets Imported
Everything in your OpenAPI spec is converted to Tigrister's project structure:
API Structure
- Info - Title, description, version, contact
- Tags - Become Modules in Tigrister
- Paths - Become Endpoints with full configuration
- Servers - Base URLs for the API
Components
- Schemas - Data models for request/response
- Security Schemes - API Key, OAuth2, etc.
- Parameters - Query, header, path, cookie params
- Webhooks - OpenAPI 3.1 webhook definitions
Swagger 2.0 Auto-Conversion
AutomaticWhen you import a Swagger 2.0 specification, Tigrister automatically converts it to OpenAPI 3.0.3.
Conversion includes:
- •
host+basePath+schemes→serversarray - •
definitions→components/schemas - •
securityDefinitions→components/securitySchemes - •Body parameters →
requestBody - •
consumes/produces→ Content-Type in operations
Note
After import, a badge shows "Swagger 2.0 → 3.0" in the toolbar. The converted spec can then be exported as OpenAPI 3.0 or 3.1.
Common Import Errors
If import fails, check for these common issues:
Invalid YAML/JSON Syntax
Fix: Check for missing colons, wrong indentation, or unclosed brackets.
Not a Valid OpenAPI Spec
Fix: Ensure file has openapi: "3.x.x" or swagger: "2.0" at root, and includes the info object with title and version.
URL Fetch Failed
Fix: Check the URL is correct and accessible. If the server blocks direct requests, download the file manually and use "Upload File" instead.
Unsupported Security Schemes
If your spec includes security schemes that Tigrister doesn't support yet, a warning dialog appears before import.
Supported
- apiKey
- http (Basic, Bearer, etc.)
- oauth2
- openIdConnect
Not Yet Supported
- mutualTLS
The following security schemes are not yet supported:
• "petAuth" uses Mutual TLS (not yet supported)
These will be set to "No Auth". You can configure authentication manually after import.
Post-Import Checklist
After importing, verify everything looks correct:
Structure
Content
Quick Test
Try sending a request to a simple GET endpoint to verify the base URL and auth work correctly.
Handling Large Specs
Large API specs (1000+ endpoints) may take longer to import. Tips for best results:
Use File Upload for Large Specs
Downloading locally first avoids timeout issues with URL import.
Consider Splitting by Tag
If you only need certain endpoints, extract those paths into a smaller spec.
Be Patient with GitHub/Stripe APIs
These specs have 500+ endpoints and may take 10-20 seconds to fully load.
| Spec Size | Endpoints | Expected Load Time |
|---|---|---|
| Small | < 50 | < 1 second |
| Medium | 50-200 | 1-3 seconds |
| Large | 200+ | 5-20 seconds |
Try It Out
Import a popular public API spec to explore the feature:
Petstore (OpenAPI 3.0)
https://petstore3.swagger.io/api/v3/openapi.json
GitHub API
https://raw.githubusercontent.com/github/rest-api-description/main/descriptions/api.github.com/api.github.com.json
Stripe API
https://raw.githubusercontent.com/stripe/openapi/master/openapi/spec3.json
Twilio API
https://raw.githubusercontent.com/twilio/twilio-oai/main/spec/json/twilio_api_v2010.json
Slack Web API
https://raw.githubusercontent.com/slackapi/slack-api-specs/master/web-api/slack_web_openapi_v2.json