|
| 1 | +package errors |
| 2 | + |
| 3 | +import ( |
| 4 | +"context" |
| 5 | +"fmt" |
| 6 | +"net/http" |
| 7 | +"testing" |
| 8 | + |
| 9 | +"github.com/google/go-github/v72/github" |
| 10 | +"github.com/stretchr/testify/assert" |
| 11 | +"github.com/stretchr/testify/require" |
| 12 | +) |
| 13 | + |
| 14 | +funcTestGitHubErrorContext(t*testing.T) { |
| 15 | +t.Run("API errors can be added to context and retrieved",func(t*testing.T) { |
| 16 | +// Given a context with GitHub error tracking enabled |
| 17 | +ctx:=ContextWithGitHubErrors(context.Background()) |
| 18 | + |
| 19 | +// Create a mock GitHub response |
| 20 | +resp:=&github.Response{ |
| 21 | +Response:&http.Response{ |
| 22 | +StatusCode:404, |
| 23 | +Status:"404 Not Found", |
| 24 | +}, |
| 25 | +} |
| 26 | +originalErr:=fmt.Errorf("resource not found") |
| 27 | + |
| 28 | +// When we add an API error to the context |
| 29 | +updatedCtx,err:=NewGitHubAPIErrorToCtx(ctx,"failed to fetch resource",resp,originalErr) |
| 30 | +require.NoError(t,err) |
| 31 | + |
| 32 | +// Then we should be able to retrieve the error from the updated context |
| 33 | +apiErrors,err:=GetGitHubAPIErrors(updatedCtx) |
| 34 | +require.NoError(t,err) |
| 35 | +require.Len(t,apiErrors,1) |
| 36 | + |
| 37 | +apiError:=apiErrors[0] |
| 38 | +assert.Equal(t,"failed to fetch resource",apiError.Message) |
| 39 | +assert.Equal(t,resp,apiError.Response) |
| 40 | +assert.Equal(t,originalErr,apiError.Err) |
| 41 | +assert.Equal(t,"failed to fetch resource: resource not found",apiError.Error()) |
| 42 | +}) |
| 43 | + |
| 44 | +t.Run("GraphQL errors can be added to context and retrieved",func(t*testing.T) { |
| 45 | +// Given a context with GitHub error tracking enabled |
| 46 | +ctx:=ContextWithGitHubErrors(context.Background()) |
| 47 | + |
| 48 | +originalErr:=fmt.Errorf("GraphQL query failed") |
| 49 | + |
| 50 | +// When we add a GraphQL error to the context |
| 51 | +graphQLErr:=newGitHubGraphQLError("failed to execute mutation",originalErr) |
| 52 | +updatedCtx,err:=addGitHubGraphQLErrorToContext(ctx,graphQLErr) |
| 53 | +require.NoError(t,err) |
| 54 | + |
| 55 | +// Then we should be able to retrieve the error from the updated context |
| 56 | +gqlErrors,err:=GetGitHubGraphQLErrors(updatedCtx) |
| 57 | +require.NoError(t,err) |
| 58 | +require.Len(t,gqlErrors,1) |
| 59 | + |
| 60 | +gqlError:=gqlErrors[0] |
| 61 | +assert.Equal(t,"failed to execute mutation",gqlError.Message) |
| 62 | +assert.Equal(t,originalErr,gqlError.Err) |
| 63 | +assert.Equal(t,"failed to execute mutation: GraphQL query failed",gqlError.Error()) |
| 64 | +}) |
| 65 | + |
| 66 | +t.Run("multiple errors can be accumulated in context",func(t*testing.T) { |
| 67 | +// Given a context with GitHub error tracking enabled |
| 68 | +ctx:=ContextWithGitHubErrors(context.Background()) |
| 69 | + |
| 70 | +// When we add multiple API errors |
| 71 | +resp1:=&github.Response{Response:&http.Response{StatusCode:404}} |
| 72 | +resp2:=&github.Response{Response:&http.Response{StatusCode:403}} |
| 73 | + |
| 74 | +ctx,err:=NewGitHubAPIErrorToCtx(ctx,"first error",resp1,fmt.Errorf("not found")) |
| 75 | +require.NoError(t,err) |
| 76 | + |
| 77 | +ctx,err=NewGitHubAPIErrorToCtx(ctx,"second error",resp2,fmt.Errorf("forbidden")) |
| 78 | +require.NoError(t,err) |
| 79 | + |
| 80 | +// And add a GraphQL error |
| 81 | +gqlErr:=newGitHubGraphQLError("graphql error",fmt.Errorf("query failed")) |
| 82 | +ctx,err=addGitHubGraphQLErrorToContext(ctx,gqlErr) |
| 83 | +require.NoError(t,err) |
| 84 | + |
| 85 | +// Then we should be able to retrieve all errors |
| 86 | +apiErrors,err:=GetGitHubAPIErrors(ctx) |
| 87 | +require.NoError(t,err) |
| 88 | +assert.Len(t,apiErrors,2) |
| 89 | + |
| 90 | +gqlErrors,err:=GetGitHubGraphQLErrors(ctx) |
| 91 | +require.NoError(t,err) |
| 92 | +assert.Len(t,gqlErrors,1) |
| 93 | + |
| 94 | +// Verify error details |
| 95 | +assert.Equal(t,"first error",apiErrors[0].Message) |
| 96 | +assert.Equal(t,"second error",apiErrors[1].Message) |
| 97 | +assert.Equal(t,"graphql error",gqlErrors[0].Message) |
| 98 | +}) |
| 99 | + |
| 100 | +t.Run("context pointer sharing allows middleware to inspect errors without context propagation",func(t*testing.T) { |
| 101 | +// This test demonstrates the key behavior: even when the context itself |
| 102 | +// isn't propagated through function calls, the pointer to the error slice |
| 103 | +// is shared, allowing middleware to inspect errors that were added later. |
| 104 | + |
| 105 | +// Given a context with GitHub error tracking enabled |
| 106 | +originalCtx:=ContextWithGitHubErrors(context.Background()) |
| 107 | + |
| 108 | +// Simulate a middleware that captures the context early |
| 109 | +varmiddlewareCtx context.Context |
| 110 | + |
| 111 | +// Middleware function that captures the context |
| 112 | +middleware:=func(ctx context.Context) { |
| 113 | +middlewareCtx=ctx// Middleware saves the context reference |
| 114 | +} |
| 115 | + |
| 116 | +// Call middleware with the original context |
| 117 | +middleware(originalCtx) |
| 118 | + |
| 119 | +// Simulate some business logic that adds errors to the context |
| 120 | +// but doesn't propagate the updated context back to middleware |
| 121 | +businessLogic:=func(ctx context.Context) { |
| 122 | +resp:=&github.Response{Response:&http.Response{StatusCode:500}} |
| 123 | + |
| 124 | +// Add an error to the context (this modifies the shared pointer) |
| 125 | +_,err:=NewGitHubAPIErrorToCtx(ctx,"business logic failed",resp,fmt.Errorf("internal error")) |
| 126 | +require.NoError(t,err) |
| 127 | + |
| 128 | +// Add another error |
| 129 | +_,err=NewGitHubAPIErrorToCtx(ctx,"second failure",resp,fmt.Errorf("another error")) |
| 130 | +require.NoError(t,err) |
| 131 | +} |
| 132 | + |
| 133 | +// Execute business logic - note that we don't propagate the returned context |
| 134 | +businessLogic(originalCtx) |
| 135 | + |
| 136 | +// Then the middleware should be able to see the errors that were added |
| 137 | +// even though it only has a reference to the original context |
| 138 | +apiErrors,err:=GetGitHubAPIErrors(middlewareCtx) |
| 139 | +require.NoError(t,err) |
| 140 | +assert.Len(t,apiErrors,2,"Middleware should see errors added after it captured the context") |
| 141 | + |
| 142 | +assert.Equal(t,"business logic failed",apiErrors[0].Message) |
| 143 | +assert.Equal(t,"second failure",apiErrors[1].Message) |
| 144 | +}) |
| 145 | + |
| 146 | +t.Run("context without GitHub errors returns error",func(t*testing.T) { |
| 147 | +// Given a regular context without GitHub error tracking |
| 148 | +ctx:=context.Background() |
| 149 | + |
| 150 | +// When we try to retrieve errors |
| 151 | +apiErrors,err:=GetGitHubAPIErrors(ctx) |
| 152 | + |
| 153 | +// Then it should return an error |
| 154 | +assert.Error(t,err) |
| 155 | +assert.Contains(t,err.Error(),"context does not contain GitHubCtxErrors") |
| 156 | +assert.Nil(t,apiErrors) |
| 157 | + |
| 158 | +// Same for GraphQL errors |
| 159 | +gqlErrors,err:=GetGitHubGraphQLErrors(ctx) |
| 160 | +assert.Error(t,err) |
| 161 | +assert.Contains(t,err.Error(),"context does not contain GitHubCtxErrors") |
| 162 | +assert.Nil(t,gqlErrors) |
| 163 | +}) |
| 164 | + |
| 165 | +t.Run("ContextWithGitHubErrors resets existing errors",func(t*testing.T) { |
| 166 | +// Given a context with existing errors |
| 167 | +ctx:=ContextWithGitHubErrors(context.Background()) |
| 168 | +resp:=&github.Response{Response:&http.Response{StatusCode:404}} |
| 169 | +ctx,err:=NewGitHubAPIErrorToCtx(ctx,"existing error",resp,fmt.Errorf("error")) |
| 170 | +require.NoError(t,err) |
| 171 | + |
| 172 | +// Verify error exists |
| 173 | +apiErrors,err:=GetGitHubAPIErrors(ctx) |
| 174 | +require.NoError(t,err) |
| 175 | +assert.Len(t,apiErrors,1) |
| 176 | + |
| 177 | +// When we call ContextWithGitHubErrors again |
| 178 | +resetCtx:=ContextWithGitHubErrors(ctx) |
| 179 | + |
| 180 | +// Then the errors should be cleared |
| 181 | +apiErrors,err=GetGitHubAPIErrors(resetCtx) |
| 182 | +require.NoError(t,err) |
| 183 | +assert.Len(t,apiErrors,0,"Errors should be reset") |
| 184 | +}) |
| 185 | + |
| 186 | +t.Run("NewGitHubAPIErrorResponse creates MCP error result and stores context error",func(t*testing.T) { |
| 187 | +// Given a context with GitHub error tracking enabled |
| 188 | +ctx:=ContextWithGitHubErrors(context.Background()) |
| 189 | + |
| 190 | +resp:=&github.Response{Response:&http.Response{StatusCode:422}} |
| 191 | +originalErr:=fmt.Errorf("validation failed") |
| 192 | + |
| 193 | +// When we create an API error response |
| 194 | +result:=NewGitHubAPIErrorResponse(ctx,"API call failed",resp,originalErr) |
| 195 | + |
| 196 | +// Then it should return an MCP error result |
| 197 | +require.NotNil(t,result) |
| 198 | +assert.True(t,result.IsError) |
| 199 | + |
| 200 | +// And the error should be stored in the context |
| 201 | +apiErrors,err:=GetGitHubAPIErrors(ctx) |
| 202 | +require.NoError(t,err) |
| 203 | +require.Len(t,apiErrors,1) |
| 204 | + |
| 205 | +apiError:=apiErrors[0] |
| 206 | +assert.Equal(t,"API call failed",apiError.Message) |
| 207 | +assert.Equal(t,resp,apiError.Response) |
| 208 | +assert.Equal(t,originalErr,apiError.Err) |
| 209 | +}) |
| 210 | + |
| 211 | +t.Run("NewGitHubGraphQLErrorResponse creates MCP error result and stores context error",func(t*testing.T) { |
| 212 | +// Given a context with GitHub error tracking enabled |
| 213 | +ctx:=ContextWithGitHubErrors(context.Background()) |
| 214 | + |
| 215 | +originalErr:=fmt.Errorf("mutation failed") |
| 216 | + |
| 217 | +// When we create a GraphQL error response |
| 218 | +result:=NewGitHubGraphQLErrorResponse(ctx,"GraphQL call failed",originalErr) |
| 219 | + |
| 220 | +// Then it should return an MCP error result |
| 221 | +require.NotNil(t,result) |
| 222 | +assert.True(t,result.IsError) |
| 223 | + |
| 224 | +// And the error should be stored in the context |
| 225 | +gqlErrors,err:=GetGitHubGraphQLErrors(ctx) |
| 226 | +require.NoError(t,err) |
| 227 | +require.Len(t,gqlErrors,1) |
| 228 | + |
| 229 | +gqlError:=gqlErrors[0] |
| 230 | +assert.Equal(t,"GraphQL call failed",gqlError.Message) |
| 231 | +assert.Equal(t,originalErr,gqlError.Err) |
| 232 | +}) |
| 233 | + |
| 234 | +t.Run("NewGitHubAPIErrorToCtx with uninitialized context does not error",func(t*testing.T) { |
| 235 | +// Given a regular context without GitHub error tracking initialized |
| 236 | +ctx:=context.Background() |
| 237 | + |
| 238 | +// Create a mock GitHub response |
| 239 | +resp:=&github.Response{ |
| 240 | +Response:&http.Response{ |
| 241 | +StatusCode:500, |
| 242 | +Status:"500 Internal Server Error", |
| 243 | +}, |
| 244 | +} |
| 245 | +originalErr:=fmt.Errorf("internal server error") |
| 246 | + |
| 247 | +// When we try to add an API error to an uninitialized context |
| 248 | +updatedCtx,err:=NewGitHubAPIErrorToCtx(ctx,"failed operation",resp,originalErr) |
| 249 | + |
| 250 | +// Then it should not return an error (graceful handling) |
| 251 | +assert.NoError(t,err,"NewGitHubAPIErrorToCtx should handle uninitialized context gracefully") |
| 252 | +assert.Equal(t,ctx,updatedCtx,"Context should be returned unchanged when not initialized") |
| 253 | + |
| 254 | +// And attempting to retrieve errors should still return an error since context wasn't initialized |
| 255 | +apiErrors,err:=GetGitHubAPIErrors(updatedCtx) |
| 256 | +assert.Error(t,err) |
| 257 | +assert.Contains(t,err.Error(),"context does not contain GitHubCtxErrors") |
| 258 | +assert.Nil(t,apiErrors) |
| 259 | +}) |
| 260 | + |
| 261 | +t.Run("NewGitHubAPIErrorToCtx with nil context does not error",func(t*testing.T) { |
| 262 | +// Given a nil context |
| 263 | +varctx context.Context=nil |
| 264 | + |
| 265 | +// Create a mock GitHub response |
| 266 | +resp:=&github.Response{ |
| 267 | +Response:&http.Response{ |
| 268 | +StatusCode:400, |
| 269 | +Status:"400 Bad Request", |
| 270 | +}, |
| 271 | +} |
| 272 | +originalErr:=fmt.Errorf("bad request") |
| 273 | + |
| 274 | +// When we try to add an API error to a nil context |
| 275 | +updatedCtx,err:=NewGitHubAPIErrorToCtx(ctx,"failed with nil context",resp,originalErr) |
| 276 | + |
| 277 | +// Then it should not return an error (graceful handling) |
| 278 | +assert.NoError(t,err,"NewGitHubAPIErrorToCtx should handle nil context gracefully") |
| 279 | +assert.Nil(t,updatedCtx,"Context should remain nil when passed as nil") |
| 280 | +}) |
| 281 | +} |
| 282 | + |
| 283 | +funcTestGitHubErrorTypes(t*testing.T) { |
| 284 | +t.Run("GitHubAPIError implements error interface",func(t*testing.T) { |
| 285 | +resp:=&github.Response{Response:&http.Response{StatusCode:404}} |
| 286 | +originalErr:=fmt.Errorf("not found") |
| 287 | + |
| 288 | +apiErr:=newGitHubAPIError("test message",resp,originalErr) |
| 289 | + |
| 290 | +// Should implement error interface |
| 291 | +varerrerror=apiErr |
| 292 | +assert.Equal(t,"test message: not found",err.Error()) |
| 293 | +}) |
| 294 | + |
| 295 | +t.Run("GitHubGraphQLError implements error interface",func(t*testing.T) { |
| 296 | +originalErr:=fmt.Errorf("query failed") |
| 297 | + |
| 298 | +gqlErr:=newGitHubGraphQLError("test message",originalErr) |
| 299 | + |
| 300 | +// Should implement error interface |
| 301 | +varerrerror=gqlErr |
| 302 | +assert.Equal(t,"test message: query failed",err.Error()) |
| 303 | +}) |
| 304 | +} |
| 305 | + |
| 306 | +// TestMiddlewareScenario demonstrates a realistic middleware scenario |
| 307 | +funcTestMiddlewareScenario(t*testing.T) { |
| 308 | +t.Run("realistic middleware error collection scenario",func(t*testing.T) { |
| 309 | +// Simulate a realistic HTTP middleware scenario |
| 310 | + |
| 311 | +// 1. Request comes in, middleware sets up error tracking |
| 312 | +ctx:=ContextWithGitHubErrors(context.Background()) |
| 313 | + |
| 314 | +// 2. Middleware stores reference to context for later inspection |
| 315 | +varmiddlewareCtx context.Context |
| 316 | +setupMiddleware:=func(ctx context.Context) context.Context { |
| 317 | +middlewareCtx=ctx |
| 318 | +returnctx |
| 319 | +} |
| 320 | + |
| 321 | +// 3. Setup middleware |
| 322 | +ctx=setupMiddleware(ctx) |
| 323 | + |
| 324 | +// 4. Simulate multiple service calls that add errors |
| 325 | +simulateServiceCall1:=func(ctx context.Context) { |
| 326 | +resp:=&github.Response{Response:&http.Response{StatusCode:403}} |
| 327 | +_,err:=NewGitHubAPIErrorToCtx(ctx,"insufficient permissions",resp,fmt.Errorf("forbidden")) |
| 328 | +require.NoError(t,err) |
| 329 | +} |
| 330 | + |
| 331 | +simulateServiceCall2:=func(ctx context.Context) { |
| 332 | +resp:=&github.Response{Response:&http.Response{StatusCode:404}} |
| 333 | +_,err:=NewGitHubAPIErrorToCtx(ctx,"resource not found",resp,fmt.Errorf("not found")) |
| 334 | +require.NoError(t,err) |
| 335 | +} |
| 336 | + |
| 337 | +simulateGraphQLCall:=func(ctx context.Context) { |
| 338 | +gqlErr:=newGitHubGraphQLError("mutation failed",fmt.Errorf("invalid input")) |
| 339 | +_,err:=addGitHubGraphQLErrorToContext(ctx,gqlErr) |
| 340 | +require.NoError(t,err) |
| 341 | +} |
| 342 | + |
| 343 | +// 5. Execute service calls (without context propagation) |
| 344 | +simulateServiceCall1(ctx) |
| 345 | +simulateServiceCall2(ctx) |
| 346 | +simulateGraphQLCall(ctx) |
| 347 | + |
| 348 | +// 6. Middleware inspects errors at the end of request processing |
| 349 | +finalizeMiddleware:=func(ctx context.Context) ([]string, []string) { |
| 350 | +varapiErrorMessages []string |
| 351 | +vargqlErrorMessages []string |
| 352 | + |
| 353 | +ifapiErrors,err:=GetGitHubAPIErrors(ctx);err==nil { |
| 354 | +for_,apiErr:=rangeapiErrors { |
| 355 | +apiErrorMessages=append(apiErrorMessages,apiErr.Message) |
| 356 | +} |
| 357 | +} |
| 358 | + |
| 359 | +ifgqlErrors,err:=GetGitHubGraphQLErrors(ctx);err==nil { |
| 360 | +for_,gqlErr:=rangegqlErrors { |
| 361 | +gqlErrorMessages=append(gqlErrorMessages,gqlErr.Message) |
| 362 | +} |
| 363 | +} |
| 364 | + |
| 365 | +returnapiErrorMessages,gqlErrorMessages |
| 366 | +} |
| 367 | + |
| 368 | +// 7. Middleware can see all errors that were added during request processing |
| 369 | +apiMessages,gqlMessages:=finalizeMiddleware(middlewareCtx) |
| 370 | + |
| 371 | +// Verify all errors were captured |
| 372 | +assert.Len(t,apiMessages,2) |
| 373 | +assert.Contains(t,apiMessages,"insufficient permissions") |
| 374 | +assert.Contains(t,apiMessages,"resource not found") |
| 375 | + |
| 376 | +assert.Len(t,gqlMessages,1) |
| 377 | +assert.Contains(t,gqlMessages,"mutation failed") |
| 378 | +}) |
| 379 | +} |