import { createReadResourceHandler } from '../read.handler'
import { findProviderByUri } from '../../findProviderByUri'
import type {
ResourceDefinition,
ResourceProvider,
ResourceContent,
ResourceProviderContext,
} from '../../types/resource.types'
import type { ReadResourceRequest } from '../types'
import type { Result } from '../../../errors/types'
import { ErrorCode as McpErrorCode, McpError } from '@modelcontextprotocol/sdk/types.js'
// Mock dependencies
jest.mock('../../findProviderByUri')
jest.mock('../../../utils/logger', () => ({
log: jest.fn(),
}))
describe('createReadResourceHandler', () => {
// Mock Jira config
const mockJiraConfig = {
baseUrl: 'https://jira.example.com',
username: 'test-user',
apiToken: 'test-token',
}
// Mock resource definitions array
const mockResourceDefinitions: ResourceDefinition[] = []
// Mock URI for testing
const testUri = 'test:resource:123'
// Reset mocks before each test
beforeEach(() => {
jest.resetAllMocks()
})
test('successfully returns resource content when provider succeeds', async () => {
// Mock successful provider
const mockSuccessProvider: ResourceProvider = async (
uri: string,
_context: ResourceProviderContext,
): Promise<Result<ResourceContent, Error>> => {
return {
success: true,
data: {
content: `Content for ${uri}`,
mimeType: 'text/plain',
},
}
}
// Mock findProviderByUri to return our success provider
const mockFindProvider = findProviderByUri as jest.MockedFunction<typeof findProviderByUri>
mockFindProvider.mockReturnValue(mockSuccessProvider)
// Create handler
const handler = createReadResourceHandler(mockJiraConfig, mockResourceDefinitions)
// Create test request
const request: ReadResourceRequest = {
method: 'resources/read',
params: {
uri: testUri,
},
}
// Call handler
const result = await handler(request)
// Verify findProviderByUri was called with correct args
expect(findProviderByUri).toHaveBeenCalledWith(testUri, mockResourceDefinitions)
// Verify result structure
expect(result).toEqual({
contents: [
{
text: `Content for ${testUri}`,
mimeType: 'text/plain',
uri: testUri,
},
],
})
})
test('throws MethodNotFound error when no provider is found', async () => {
// Mock findProviderByUri to return undefined (no provider found)
const mockFindProvider = findProviderByUri as jest.MockedFunction<typeof findProviderByUri>
mockFindProvider.mockReturnValue(undefined)
// Create handler
const handler = createReadResourceHandler(mockJiraConfig, mockResourceDefinitions)
// Create test request
const request: ReadResourceRequest = {
method: 'resources/read',
params: {
uri: testUri,
},
}
// Call handler and verify expected error
await expect(handler(request)).rejects.toThrow(
new McpError(McpErrorCode.MethodNotFound, `Resource provider not found for URI: ${testUri}`),
)
// Verify findProviderByUri was called with correct args
expect(findProviderByUri).toHaveBeenCalledWith(testUri, mockResourceDefinitions)
})
test('throws InternalError when provider returns an error', async () => {
// Mock error provider
const mockErrorProvider: ResourceProvider = async (
_uri: string,
_context: ResourceProviderContext,
): Promise<Result<ResourceContent, Error>> => {
return {
success: false,
error: new Error('Provider error'),
}
}
// Mock findProviderByUri to return our error provider
const mockFindProvider = findProviderByUri as jest.MockedFunction<typeof findProviderByUri>
mockFindProvider.mockReturnValue(mockErrorProvider)
// Create handler
const handler = createReadResourceHandler(mockJiraConfig, mockResourceDefinitions)
// Create test request
const request: ReadResourceRequest = {
method: 'resources/read',
params: {
uri: testUri,
},
}
// Call handler and verify expected error
await expect(handler(request)).rejects.toThrow(
new McpError(McpErrorCode.InternalError, `Unexpected error reading resource: ${testUri}`),
)
})
test('passes through McpError when provider returns it', async () => {
// Create an MCP error to be returned by the provider
const mcpError = new McpError(McpErrorCode.InvalidParams, 'Bad input error')
// Mock provider that returns an MCP error
const mockMcpErrorProvider: ResourceProvider = async (
_uri: string,
_context: ResourceProviderContext,
): Promise<Result<ResourceContent, Error>> => {
return {
success: false,
error: mcpError,
}
}
// Mock findProviderByUri to return our MCP error provider
const mockFindProvider = findProviderByUri as jest.MockedFunction<typeof findProviderByUri>
mockFindProvider.mockReturnValue(mockMcpErrorProvider)
// Create handler
const handler = createReadResourceHandler(mockJiraConfig, mockResourceDefinitions)
// Create test request
const request: ReadResourceRequest = {
method: 'resources/read',
params: {
uri: testUri,
},
}
// Call handler and verify that the original MCP error is passed through
await expect(handler(request)).rejects.toThrow(mcpError)
})
test('passes Jira config in the context to the provider', async () => {
// Create a spy provider to check the context
let capturedContext: ResourceProviderContext | undefined
const spyProvider: ResourceProvider = async (
_uri: string,
context: ResourceProviderContext,
): Promise<Result<ResourceContent, Error>> => {
capturedContext = context
return {
success: true,
data: {
content: 'test content',
mimeType: 'text/plain',
},
}
}
// Mock findProviderByUri to return our spy provider
const mockFindProvider = findProviderByUri as jest.MockedFunction<typeof findProviderByUri>
mockFindProvider.mockReturnValue(spyProvider)
// Create handler
const handler = createReadResourceHandler(mockJiraConfig, mockResourceDefinitions)
// Create test request
const request: ReadResourceRequest = {
method: 'resources/read',
params: {
uri: testUri,
},
}
// Call handler
await handler(request)
// Verify the context passed to the provider
expect(capturedContext).toBeDefined()
expect(capturedContext?.jiraConfig).toBe(mockJiraConfig)
})
})
