Serge Bazanski | cc25bdf | 2018-10-25 14:02:58 +0200 | [diff] [blame] | 1 | // Package jsonrpc provides a JSON-RPC 2.0 client that sends JSON-RPC requests and receives JSON-RPC responses using HTTP. |
| 2 | package jsonrpc |
| 3 | |
| 4 | import ( |
| 5 | "bytes" |
| 6 | "encoding/json" |
| 7 | "errors" |
| 8 | "fmt" |
| 9 | "net/http" |
| 10 | "reflect" |
| 11 | "strconv" |
| 12 | ) |
| 13 | |
| 14 | const ( |
| 15 | jsonrpcVersion = "2.0" |
| 16 | ) |
| 17 | |
| 18 | // RPCClient sends JSON-RPC requests over HTTP to the provided JSON-RPC backend. |
| 19 | // |
| 20 | // RPCClient is created using the factory function NewClient(). |
| 21 | type RPCClient interface { |
| 22 | // Call is used to send a JSON-RPC request to the server endpoint. |
| 23 | // |
| 24 | // The spec states, that params can only be an array or an object, no primitive values. |
| 25 | // So there are a few simple rules to notice: |
| 26 | // |
| 27 | // 1. no params: params field is omitted. e.g. Call("getinfo") |
| 28 | // |
| 29 | // 2. single params primitive value: value is wrapped in array. e.g. Call("getByID", 1423) |
| 30 | // |
| 31 | // 3. single params value array or object: value is unchanged. e.g. Call("storePerson", &Person{Name: "Alex"}) |
| 32 | // |
| 33 | // 4. multiple params values: always wrapped in array. e.g. Call("setDetails", "Alex, 35, "Germany", true) |
| 34 | // |
| 35 | // Examples: |
| 36 | // Call("getinfo") -> {"method": "getinfo"} |
| 37 | // Call("getPersonId", 123) -> {"method": "getPersonId", "params": [123]} |
| 38 | // Call("setName", "Alex") -> {"method": "setName", "params": ["Alex"]} |
| 39 | // Call("setMale", true) -> {"method": "setMale", "params": [true]} |
| 40 | // Call("setNumbers", []int{1, 2, 3}) -> {"method": "setNumbers", "params": [1, 2, 3]} |
| 41 | // Call("setNumbers", 1, 2, 3) -> {"method": "setNumbers", "params": [1, 2, 3]} |
| 42 | // Call("savePerson", &Person{Name: "Alex", Age: 35}) -> {"method": "savePerson", "params": {"name": "Alex", "age": 35}} |
| 43 | // Call("setPersonDetails", "Alex", 35, "Germany") -> {"method": "setPersonDetails", "params": ["Alex", 35, "Germany"}} |
| 44 | // |
| 45 | // for more information, see the examples or the unit tests |
| 46 | Call(method string, params ...interface{}) (*RPCResponse, error) |
| 47 | |
| 48 | // CallRaw is like Call() but without magic in the requests.Params field. |
| 49 | // The RPCRequest object is sent exactly as you provide it. |
| 50 | // See docs: NewRequest, RPCRequest, Params() |
| 51 | // |
| 52 | // It is recommended to first consider Call() and CallFor() |
| 53 | CallRaw(request *RPCRequest) (*RPCResponse, error) |
| 54 | |
| 55 | // CallFor is a very handy function to send a JSON-RPC request to the server endpoint |
| 56 | // and directly specify an object to store the response. |
| 57 | // |
| 58 | // out: will store the unmarshaled object, if request was successful. |
| 59 | // should always be provided by references. can be nil even on success. |
| 60 | // the behaviour is the same as expected from json.Unmarshal() |
| 61 | // |
| 62 | // method and params: see Call() function |
| 63 | // |
| 64 | // if the request was not successful (network, http error) or the rpc response returns an error, |
| 65 | // an error is returned. if it was an JSON-RPC error it can be casted |
| 66 | // to *RPCError. |
| 67 | // |
| 68 | CallFor(out interface{}, method string, params ...interface{}) error |
| 69 | |
| 70 | // CallBatch invokes a list of RPCRequests in a single batch request. |
| 71 | // |
| 72 | // Most convenient is to use the following form: |
| 73 | // CallBatch(RPCRequests{ |
| 74 | // Batch("myMethod1", 1, 2, 3), |
| 75 | // Batch("myMethod2), "Test"), |
| 76 | // }) |
| 77 | // |
| 78 | // You can create the []*RPCRequest array yourself, but it is not recommended and you should notice the following: |
| 79 | // - field Params is sent as provided, so Params: 2 forms an invalid json (correct would be Params: []int{2}) |
| 80 | // - you can use the helper function Params(1, 2, 3) to use the same format as in Call() |
| 81 | // - field JSONRPC is overwritten and set to value: "2.0" |
| 82 | // - field ID is overwritten and set incrementally and maps to the array position (e.g. requests[5].ID == 5) |
| 83 | // |
| 84 | // |
| 85 | // Returns RPCResponses that is of type []*RPCResponse |
| 86 | // - note that a list of RPCResponses can be received unordered so it can happen that: responses[i] != responses[i].ID |
| 87 | // - RPCPersponses is enriched with helper functions e.g.: responses.HasError() returns true if one of the responses holds an RPCError |
| 88 | CallBatch(requests RPCRequests) (RPCResponses, error) |
| 89 | |
| 90 | // CallBatchRaw invokes a list of RPCRequests in a single batch request. |
| 91 | // It sends the RPCRequests parameter is it passed (no magic, no id autoincrement). |
| 92 | // |
| 93 | // Consider to use CallBatch() instead except you have some good reason not to. |
| 94 | // |
| 95 | // CallBatchRaw(RPCRequests{ |
| 96 | // &RPCRequest{ |
| 97 | // ID: 123, // this won't be replaced in CallBatchRaw |
| 98 | // JSONRPC: "wrong", // this won't be replaced in CallBatchRaw |
| 99 | // Method: "myMethod1", |
| 100 | // Params: []int{1}, // there is no magic, be sure to only use array or object |
| 101 | // }, |
| 102 | // &RPCRequest{ |
| 103 | // ID: 612, |
| 104 | // JSONRPC: "2.0", |
| 105 | // Method: "myMethod2", |
| 106 | // Params: Params("Alex", 35, true), // you can use helper function Params() (see doc) |
| 107 | // }, |
| 108 | // }) |
| 109 | // |
| 110 | // Returns RPCResponses that is of type []*RPCResponse |
| 111 | // - note that a list of RPCResponses can be received unordered |
| 112 | // - the id's must be mapped against the id's you provided |
| 113 | // - RPCPersponses is enriched with helper functions e.g.: responses.HasError() returns true if one of the responses holds an RPCError |
| 114 | CallBatchRaw(requests RPCRequests) (RPCResponses, error) |
| 115 | } |
| 116 | |
| 117 | // RPCRequest represents a JSON-RPC request object. |
| 118 | // |
| 119 | // Method: string containing the method to be invoked |
| 120 | // |
| 121 | // Params: can be nil. if not must be an json array or object |
| 122 | // |
| 123 | // ID: may always set to 1 for single requests. Should be unique for every request in one batch request. |
| 124 | // |
| 125 | // JSONRPC: must always be set to "2.0" for JSON-RPC version 2.0 |
| 126 | // |
| 127 | // See: http://www.jsonrpc.org/specification#request_object |
| 128 | // |
| 129 | // Most of the time you shouldn't create the RPCRequest object yourself. |
| 130 | // The following functions do that for you: |
| 131 | // Call(), CallFor(), NewRequest() |
| 132 | // |
| 133 | // If you want to create it yourself (e.g. in batch or CallRaw()), consider using Params(). |
| 134 | // Params() is a helper function that uses the same parameter syntax as Call(). |
| 135 | // |
| 136 | // e.g. to manually create an RPCRequest object: |
| 137 | // request := &RPCRequest{ |
| 138 | // Method: "myMethod", |
| 139 | // Params: Params("Alex", 35, true), |
| 140 | // } |
| 141 | // |
| 142 | // If you know what you are doing you can omit the Params() call to avoid some reflection but potentially create incorrect rpc requests: |
| 143 | //request := &RPCRequest{ |
| 144 | // Method: "myMethod", |
| 145 | // Params: 2, <-- invalid since a single primitive value must be wrapped in an array --> no magic without Params() |
| 146 | // } |
| 147 | // |
| 148 | // correct: |
| 149 | // request := &RPCRequest{ |
| 150 | // Method: "myMethod", |
| 151 | // Params: []int{2}, <-- invalid since a single primitive value must be wrapped in an array |
| 152 | // } |
| 153 | type RPCRequest struct { |
| 154 | Method string `json:"method"` |
| 155 | Params interface{} `json:"params,omitempty"` |
| 156 | ID int `json:"id"` |
| 157 | JSONRPC string `json:"jsonrpc"` |
| 158 | } |
| 159 | |
| 160 | // NewRequest returns a new RPCRequest that can be created using the same convenient parameter syntax as Call() |
| 161 | // |
| 162 | // e.g. NewRequest("myMethod", "Alex", 35, true) |
| 163 | func NewRequest(method string, params ...interface{}) *RPCRequest { |
| 164 | request := &RPCRequest{ |
| 165 | Method: method, |
| 166 | Params: Params(params...), |
| 167 | JSONRPC: jsonrpcVersion, |
| 168 | } |
| 169 | |
| 170 | return request |
| 171 | } |
| 172 | |
| 173 | // RPCResponse represents a JSON-RPC response object. |
| 174 | // |
| 175 | // Result: holds the result of the rpc call if no error occurred, nil otherwise. can be nil even on success. |
| 176 | // |
| 177 | // Error: holds an RPCError object if an error occurred. must be nil on success. |
| 178 | // |
| 179 | // ID: may always be 0 for single requests. is unique for each request in a batch call (see CallBatch()) |
| 180 | // |
| 181 | // JSONRPC: must always be set to "2.0" for JSON-RPC version 2.0 |
| 182 | // |
| 183 | // See: http://www.jsonrpc.org/specification#response_object |
| 184 | type RPCResponse struct { |
| 185 | JSONRPC string `json:"jsonrpc"` |
| 186 | Result interface{} `json:"result,omitempty"` |
| 187 | Error *RPCError `json:"error,omitempty"` |
| 188 | ID int `json:"id"` |
| 189 | } |
| 190 | |
| 191 | // RPCError represents a JSON-RPC error object if an RPC error occurred. |
| 192 | // |
| 193 | // Code: holds the error code |
| 194 | // |
| 195 | // Message: holds a short error message |
| 196 | // |
| 197 | // Data: holds additional error data, may be nil |
| 198 | // |
| 199 | // See: http://www.jsonrpc.org/specification#error_object |
| 200 | type RPCError struct { |
| 201 | Code int `json:"code"` |
| 202 | Message string `json:"message"` |
| 203 | Data interface{} `json:"data,omitempty"` |
| 204 | } |
| 205 | |
| 206 | // Error function is provided to be used as error object. |
| 207 | func (e *RPCError) Error() string { |
| 208 | return strconv.Itoa(e.Code) + ":" + e.Message |
| 209 | } |
| 210 | |
| 211 | // HTTPError represents a error that occurred on HTTP level. |
| 212 | // |
| 213 | // An error of type HTTPError is returned when a HTTP error occurred (status code) |
| 214 | // and the body could not be parsed to a valid RPCResponse object that holds a RPCError. |
| 215 | // |
| 216 | // Otherwise a RPCResponse object is returned with a RPCError field that is not nil. |
| 217 | type HTTPError struct { |
| 218 | Code int |
| 219 | err error |
| 220 | } |
| 221 | |
| 222 | // Error function is provided to be used as error object. |
| 223 | func (e *HTTPError) Error() string { |
| 224 | return e.err.Error() |
| 225 | } |
| 226 | |
| 227 | type rpcClient struct { |
| 228 | endpoint string |
| 229 | httpClient *http.Client |
| 230 | customHeaders map[string]string |
| 231 | } |
| 232 | |
| 233 | // RPCClientOpts can be provided to NewClientWithOpts() to change configuration of RPCClient. |
| 234 | // |
| 235 | // HTTPClient: provide a custom http.Client (e.g. to set a proxy, or tls options) |
| 236 | // |
| 237 | // CustomHeaders: provide custom headers, e.g. to set BasicAuth |
| 238 | type RPCClientOpts struct { |
| 239 | HTTPClient *http.Client |
| 240 | CustomHeaders map[string]string |
| 241 | } |
| 242 | |
| 243 | // RPCResponses is of type []*RPCResponse. |
| 244 | // This type is used to provide helper functions on the result list |
| 245 | type RPCResponses []*RPCResponse |
| 246 | |
| 247 | // AsMap returns the responses as map with response id as key. |
| 248 | func (res RPCResponses) AsMap() map[int]*RPCResponse { |
| 249 | resMap := make(map[int]*RPCResponse, 0) |
| 250 | for _, r := range res { |
| 251 | resMap[r.ID] = r |
| 252 | } |
| 253 | |
| 254 | return resMap |
| 255 | } |
| 256 | |
| 257 | // GetByID returns the response object of the given id, nil if it does not exist. |
| 258 | func (res RPCResponses) GetByID(id int) *RPCResponse { |
| 259 | for _, r := range res { |
| 260 | if r.ID == id { |
| 261 | return r |
| 262 | } |
| 263 | } |
| 264 | |
| 265 | return nil |
| 266 | } |
| 267 | |
| 268 | // HasError returns true if one of the response objects has Error field != nil |
| 269 | func (res RPCResponses) HasError() bool { |
| 270 | for _, res := range res { |
| 271 | if res.Error != nil { |
| 272 | return true |
| 273 | } |
| 274 | } |
| 275 | return false |
| 276 | } |
| 277 | |
| 278 | // RPCRequests is of type []*RPCRequest. |
| 279 | // This type is used to provide helper functions on the request list |
| 280 | type RPCRequests []*RPCRequest |
| 281 | |
| 282 | // NewClient returns a new RPCClient instance with default configuration. |
| 283 | // |
| 284 | // endpoint: JSON-RPC service URL to which JSON-RPC requests are sent. |
| 285 | func NewClient(endpoint string) RPCClient { |
| 286 | return NewClientWithOpts(endpoint, nil) |
| 287 | } |
| 288 | |
| 289 | // NewClientWithOpts returns a new RPCClient instance with custom configuration. |
| 290 | // |
| 291 | // endpoint: JSON-RPC service URL to which JSON-RPC requests are sent. |
| 292 | // |
| 293 | // opts: RPCClientOpts provide custom configuration |
| 294 | func NewClientWithOpts(endpoint string, opts *RPCClientOpts) RPCClient { |
| 295 | rpcClient := &rpcClient{ |
| 296 | endpoint: endpoint, |
| 297 | httpClient: &http.Client{}, |
| 298 | customHeaders: make(map[string]string), |
| 299 | } |
| 300 | |
| 301 | if opts == nil { |
| 302 | return rpcClient |
| 303 | } |
| 304 | |
| 305 | if opts.HTTPClient != nil { |
| 306 | rpcClient.httpClient = opts.HTTPClient |
| 307 | } |
| 308 | |
| 309 | if opts.CustomHeaders != nil { |
| 310 | for k, v := range opts.CustomHeaders { |
| 311 | rpcClient.customHeaders[k] = v |
| 312 | } |
| 313 | } |
| 314 | |
| 315 | return rpcClient |
| 316 | } |
| 317 | |
| 318 | func (client *rpcClient) Call(method string, params ...interface{}) (*RPCResponse, error) { |
| 319 | |
| 320 | request := &RPCRequest{ |
| 321 | Method: method, |
| 322 | Params: Params(params...), |
| 323 | JSONRPC: jsonrpcVersion, |
| 324 | } |
| 325 | |
| 326 | return client.doCall(request) |
| 327 | } |
| 328 | |
| 329 | func (client *rpcClient) CallRaw(request *RPCRequest) (*RPCResponse, error) { |
| 330 | |
| 331 | return client.doCall(request) |
| 332 | } |
| 333 | |
| 334 | func (client *rpcClient) CallFor(out interface{}, method string, params ...interface{}) error { |
| 335 | rpcResponse, err := client.Call(method, params...) |
| 336 | if err != nil { |
| 337 | return err |
| 338 | } |
| 339 | |
| 340 | if rpcResponse.Error != nil { |
| 341 | return rpcResponse.Error |
| 342 | } |
| 343 | |
| 344 | return rpcResponse.GetObject(out) |
| 345 | } |
| 346 | |
| 347 | func (client *rpcClient) CallBatch(requests RPCRequests) (RPCResponses, error) { |
| 348 | if len(requests) == 0 { |
| 349 | return nil, errors.New("empty request list") |
| 350 | } |
| 351 | |
| 352 | for i, req := range requests { |
| 353 | req.ID = i |
| 354 | req.JSONRPC = jsonrpcVersion |
| 355 | } |
| 356 | |
| 357 | return client.doBatchCall(requests) |
| 358 | } |
| 359 | |
| 360 | func (client *rpcClient) CallBatchRaw(requests RPCRequests) (RPCResponses, error) { |
| 361 | if len(requests) == 0 { |
| 362 | return nil, errors.New("empty request list") |
| 363 | } |
| 364 | |
| 365 | return client.doBatchCall(requests) |
| 366 | } |
| 367 | |
| 368 | func (client *rpcClient) newRequest(req interface{}) (*http.Request, error) { |
| 369 | |
| 370 | body, err := json.Marshal(req) |
| 371 | if err != nil { |
| 372 | return nil, err |
| 373 | } |
| 374 | |
| 375 | request, err := http.NewRequest("POST", client.endpoint, bytes.NewReader(body)) |
| 376 | if err != nil { |
| 377 | return nil, err |
| 378 | } |
| 379 | |
| 380 | request.Header.Set("Content-Type", "application/json") |
| 381 | request.Header.Set("Accept", "application/json") |
| 382 | |
| 383 | // set default headers first, so that even content type and accept can be overwritten |
| 384 | for k, v := range client.customHeaders { |
| 385 | request.Header.Set(k, v) |
| 386 | } |
| 387 | |
| 388 | return request, nil |
| 389 | } |
| 390 | |
| 391 | func (client *rpcClient) doCall(RPCRequest *RPCRequest) (*RPCResponse, error) { |
| 392 | |
| 393 | httpRequest, err := client.newRequest(RPCRequest) |
| 394 | if err != nil { |
| 395 | return nil, fmt.Errorf("rpc call %v() on %v: %v", RPCRequest.Method, httpRequest.URL.String(), err.Error()) |
| 396 | } |
| 397 | httpResponse, err := client.httpClient.Do(httpRequest) |
| 398 | if err != nil { |
| 399 | return nil, fmt.Errorf("rpc call %v() on %v: %v", RPCRequest.Method, httpRequest.URL.String(), err.Error()) |
| 400 | } |
| 401 | defer httpResponse.Body.Close() |
| 402 | |
| 403 | var rpcResponse *RPCResponse |
| 404 | decoder := json.NewDecoder(httpResponse.Body) |
| 405 | decoder.DisallowUnknownFields() |
| 406 | decoder.UseNumber() |
| 407 | err = decoder.Decode(&rpcResponse) |
| 408 | |
| 409 | // parsing error |
| 410 | if err != nil { |
| 411 | // if we have some http error, return it |
| 412 | if httpResponse.StatusCode >= 400 { |
| 413 | return nil, &HTTPError{ |
| 414 | Code: httpResponse.StatusCode, |
| 415 | err: fmt.Errorf("rpc call %v() on %v status code: %v. could not decode body to rpc response: %v", RPCRequest.Method, httpRequest.URL.String(), httpResponse.StatusCode, err.Error()), |
| 416 | } |
| 417 | } |
| 418 | return nil, fmt.Errorf("rpc call %v() on %v status code: %v. could not decode body to rpc response: %v", RPCRequest.Method, httpRequest.URL.String(), httpResponse.StatusCode, err.Error()) |
| 419 | } |
| 420 | |
| 421 | // response body empty |
| 422 | if rpcResponse == nil { |
| 423 | // if we have some http error, return it |
| 424 | if httpResponse.StatusCode >= 400 { |
| 425 | return nil, &HTTPError{ |
| 426 | Code: httpResponse.StatusCode, |
| 427 | err: fmt.Errorf("rpc call %v() on %v status code: %v. rpc response missing", RPCRequest.Method, httpRequest.URL.String(), httpResponse.StatusCode), |
| 428 | } |
| 429 | } |
| 430 | return nil, fmt.Errorf("rpc call %v() on %v status code: %v. rpc response missing", RPCRequest.Method, httpRequest.URL.String(), httpResponse.StatusCode) |
| 431 | } |
| 432 | |
| 433 | return rpcResponse, nil |
| 434 | } |
| 435 | |
| 436 | func (client *rpcClient) doBatchCall(rpcRequest []*RPCRequest) ([]*RPCResponse, error) { |
| 437 | httpRequest, err := client.newRequest(rpcRequest) |
| 438 | if err != nil { |
| 439 | return nil, fmt.Errorf("rpc batch call on %v: %v", httpRequest.URL.String(), err.Error()) |
| 440 | } |
| 441 | httpResponse, err := client.httpClient.Do(httpRequest) |
| 442 | if err != nil { |
| 443 | return nil, fmt.Errorf("rpc batch call on %v: %v", httpRequest.URL.String(), err.Error()) |
| 444 | } |
| 445 | defer httpResponse.Body.Close() |
| 446 | |
| 447 | var rpcResponse RPCResponses |
| 448 | decoder := json.NewDecoder(httpResponse.Body) |
| 449 | decoder.DisallowUnknownFields() |
| 450 | decoder.UseNumber() |
| 451 | err = decoder.Decode(&rpcResponse) |
| 452 | |
| 453 | // parsing error |
| 454 | if err != nil { |
| 455 | // if we have some http error, return it |
| 456 | if httpResponse.StatusCode >= 400 { |
| 457 | return nil, &HTTPError{ |
| 458 | Code: httpResponse.StatusCode, |
| 459 | err: fmt.Errorf("rpc batch call on %v status code: %v. could not decode body to rpc response: %v", httpRequest.URL.String(), httpResponse.StatusCode, err.Error()), |
| 460 | } |
| 461 | } |
| 462 | return nil, fmt.Errorf("rpc batch call on %v status code: %v. could not decode body to rpc response: %v", httpRequest.URL.String(), httpResponse.StatusCode, err.Error()) |
| 463 | } |
| 464 | |
| 465 | // response body empty |
| 466 | if rpcResponse == nil || len(rpcResponse) == 0 { |
| 467 | // if we have some http error, return it |
| 468 | if httpResponse.StatusCode >= 400 { |
| 469 | return nil, &HTTPError{ |
| 470 | Code: httpResponse.StatusCode, |
| 471 | err: fmt.Errorf("rpc batch call on %v status code: %v. rpc response missing", httpRequest.URL.String(), httpResponse.StatusCode), |
| 472 | } |
| 473 | } |
| 474 | return nil, fmt.Errorf("rpc batch call on %v status code: %v. rpc response missing", httpRequest.URL.String(), httpResponse.StatusCode) |
| 475 | } |
| 476 | |
| 477 | return rpcResponse, nil |
| 478 | } |
| 479 | |
| 480 | // Params is a helper function that uses the same parameter syntax as Call(). |
| 481 | // But you should consider to always use NewRequest() instead. |
| 482 | // |
| 483 | // e.g. to manually create an RPCRequest object: |
| 484 | // request := &RPCRequest{ |
| 485 | // Method: "myMethod", |
| 486 | // Params: Params("Alex", 35, true), |
| 487 | // } |
| 488 | // |
| 489 | // same with new request: |
| 490 | // request := NewRequest("myMethod", "Alex", 35, true) |
| 491 | // |
| 492 | // If you know what you are doing you can omit the Params() call but potentially create incorrect rpc requests: |
| 493 | //request := &RPCRequest{ |
| 494 | // Method: "myMethod", |
| 495 | // Params: 2, <-- invalid since a single primitive value must be wrapped in an array --> no magic without Params() |
| 496 | // } |
| 497 | // |
| 498 | // correct: |
| 499 | // request := &RPCRequest{ |
| 500 | // Method: "myMethod", |
| 501 | // Params: []int{2}, <-- invalid since a single primitive value must be wrapped in an array |
| 502 | // } |
| 503 | func Params(params ...interface{}) interface{} { |
| 504 | var finalParams interface{} |
| 505 | |
| 506 | // if params was nil skip this and p stays nil |
| 507 | if params != nil { |
| 508 | switch len(params) { |
| 509 | case 0: // no parameters were provided, do nothing so finalParam is nil and will be omitted |
| 510 | case 1: // one param was provided, use it directly as is, or wrap primitive types in array |
| 511 | if params[0] != nil { |
| 512 | var typeOf reflect.Type |
| 513 | |
| 514 | // traverse until nil or not a pointer type |
| 515 | for typeOf = reflect.TypeOf(params[0]); typeOf != nil && typeOf.Kind() == reflect.Ptr; typeOf = typeOf.Elem() { |
| 516 | } |
| 517 | |
| 518 | if typeOf != nil { |
| 519 | // now check if we can directly marshal the type or if it must be wrapped in an array |
| 520 | switch typeOf.Kind() { |
| 521 | // for these types we just do nothing, since value of p is already unwrapped from the array params |
| 522 | case reflect.Struct: |
| 523 | finalParams = params[0] |
| 524 | case reflect.Array: |
| 525 | finalParams = params[0] |
| 526 | case reflect.Slice: |
| 527 | finalParams = params[0] |
| 528 | case reflect.Interface: |
| 529 | finalParams = params[0] |
| 530 | case reflect.Map: |
| 531 | finalParams = params[0] |
| 532 | default: // everything else must stay in an array (int, string, etc) |
| 533 | finalParams = params |
| 534 | } |
| 535 | } |
| 536 | } else { |
| 537 | finalParams = params |
| 538 | } |
| 539 | default: // if more than one parameter was provided it should be treated as an array |
| 540 | finalParams = params |
| 541 | } |
| 542 | } |
| 543 | |
| 544 | return finalParams |
| 545 | } |
| 546 | |
| 547 | // GetInt converts the rpc response to an int64 and returns it. |
| 548 | // |
| 549 | // If result was not an integer an error is returned. |
| 550 | func (RPCResponse *RPCResponse) GetInt() (int64, error) { |
| 551 | val, ok := RPCResponse.Result.(json.Number) |
| 552 | if !ok { |
| 553 | return 0, fmt.Errorf("could not parse int64 from %s", RPCResponse.Result) |
| 554 | } |
| 555 | |
| 556 | i, err := val.Int64() |
| 557 | if err != nil { |
| 558 | return 0, err |
| 559 | } |
| 560 | |
| 561 | return i, nil |
| 562 | } |
| 563 | |
| 564 | // GetFloat converts the rpc response to float64 and returns it. |
| 565 | // |
| 566 | // If result was not an float64 an error is returned. |
| 567 | func (RPCResponse *RPCResponse) GetFloat() (float64, error) { |
| 568 | val, ok := RPCResponse.Result.(json.Number) |
| 569 | if !ok { |
| 570 | return 0, fmt.Errorf("could not parse float64 from %s", RPCResponse.Result) |
| 571 | } |
| 572 | |
| 573 | f, err := val.Float64() |
| 574 | if err != nil { |
| 575 | return 0, err |
| 576 | } |
| 577 | |
| 578 | return f, nil |
| 579 | } |
| 580 | |
| 581 | // GetBool converts the rpc response to a bool and returns it. |
| 582 | // |
| 583 | // If result was not a bool an error is returned. |
| 584 | func (RPCResponse *RPCResponse) GetBool() (bool, error) { |
| 585 | val, ok := RPCResponse.Result.(bool) |
| 586 | if !ok { |
| 587 | return false, fmt.Errorf("could not parse bool from %s", RPCResponse.Result) |
| 588 | } |
| 589 | |
| 590 | return val, nil |
| 591 | } |
| 592 | |
| 593 | // GetString converts the rpc response to a string and returns it. |
| 594 | // |
| 595 | // If result was not a string an error is returned. |
| 596 | func (RPCResponse *RPCResponse) GetString() (string, error) { |
| 597 | val, ok := RPCResponse.Result.(string) |
| 598 | if !ok { |
| 599 | return "", fmt.Errorf("could not parse string from %s", RPCResponse.Result) |
| 600 | } |
| 601 | |
| 602 | return val, nil |
| 603 | } |
| 604 | |
| 605 | // GetObject converts the rpc response to an arbitrary type. |
| 606 | // |
| 607 | // The function works as you would expect it from json.Unmarshal() |
| 608 | func (RPCResponse *RPCResponse) GetObject(toType interface{}) error { |
| 609 | js, err := json.Marshal(RPCResponse.Result) |
| 610 | if err != nil { |
| 611 | return err |
| 612 | } |
| 613 | |
| 614 | err = json.Unmarshal(js, toType) |
| 615 | if err != nil { |
| 616 | return err |
| 617 | } |
| 618 | |
| 619 | return nil |
| 620 | } |