diff options
Diffstat (limited to 'vendor/github.com/jmespath/go-jmespath/interpreter.go')
-rw-r--r-- | vendor/github.com/jmespath/go-jmespath/interpreter.go | 418 |
1 files changed, 418 insertions, 0 deletions
diff --git a/vendor/github.com/jmespath/go-jmespath/interpreter.go b/vendor/github.com/jmespath/go-jmespath/interpreter.go new file mode 100644 index 0000000..13c7460 --- /dev/null +++ b/vendor/github.com/jmespath/go-jmespath/interpreter.go | |||
@@ -0,0 +1,418 @@ | |||
1 | package jmespath | ||
2 | |||
3 | import ( | ||
4 | "errors" | ||
5 | "reflect" | ||
6 | "unicode" | ||
7 | "unicode/utf8" | ||
8 | ) | ||
9 | |||
10 | /* This is a tree based interpreter. It walks the AST and directly | ||
11 | interprets the AST to search through a JSON document. | ||
12 | */ | ||
13 | |||
14 | type treeInterpreter struct { | ||
15 | fCall *functionCaller | ||
16 | } | ||
17 | |||
18 | func newInterpreter() *treeInterpreter { | ||
19 | interpreter := treeInterpreter{} | ||
20 | interpreter.fCall = newFunctionCaller() | ||
21 | return &interpreter | ||
22 | } | ||
23 | |||
24 | type expRef struct { | ||
25 | ref ASTNode | ||
26 | } | ||
27 | |||
28 | // Execute takes an ASTNode and input data and interprets the AST directly. | ||
29 | // It will produce the result of applying the JMESPath expression associated | ||
30 | // with the ASTNode to the input data "value". | ||
31 | func (intr *treeInterpreter) Execute(node ASTNode, value interface{}) (interface{}, error) { | ||
32 | switch node.nodeType { | ||
33 | case ASTComparator: | ||
34 | left, err := intr.Execute(node.children[0], value) | ||
35 | if err != nil { | ||
36 | return nil, err | ||
37 | } | ||
38 | right, err := intr.Execute(node.children[1], value) | ||
39 | if err != nil { | ||
40 | return nil, err | ||
41 | } | ||
42 | switch node.value { | ||
43 | case tEQ: | ||
44 | return objsEqual(left, right), nil | ||
45 | case tNE: | ||
46 | return !objsEqual(left, right), nil | ||
47 | } | ||
48 | leftNum, ok := left.(float64) | ||
49 | if !ok { | ||
50 | return nil, nil | ||
51 | } | ||
52 | rightNum, ok := right.(float64) | ||
53 | if !ok { | ||
54 | return nil, nil | ||
55 | } | ||
56 | switch node.value { | ||
57 | case tGT: | ||
58 | return leftNum > rightNum, nil | ||
59 | case tGTE: | ||
60 | return leftNum >= rightNum, nil | ||
61 | case tLT: | ||
62 | return leftNum < rightNum, nil | ||
63 | case tLTE: | ||
64 | return leftNum <= rightNum, nil | ||
65 | } | ||
66 | case ASTExpRef: | ||
67 | return expRef{ref: node.children[0]}, nil | ||
68 | case ASTFunctionExpression: | ||
69 | resolvedArgs := []interface{}{} | ||
70 | for _, arg := range node.children { | ||
71 | current, err := intr.Execute(arg, value) | ||
72 | if err != nil { | ||
73 | return nil, err | ||
74 | } | ||
75 | resolvedArgs = append(resolvedArgs, current) | ||
76 | } | ||
77 | return intr.fCall.CallFunction(node.value.(string), resolvedArgs, intr) | ||
78 | case ASTField: | ||
79 | if m, ok := value.(map[string]interface{}); ok { | ||
80 | key := node.value.(string) | ||
81 | return m[key], nil | ||
82 | } | ||
83 | return intr.fieldFromStruct(node.value.(string), value) | ||
84 | case ASTFilterProjection: | ||
85 | left, err := intr.Execute(node.children[0], value) | ||
86 | if err != nil { | ||
87 | return nil, nil | ||
88 | } | ||
89 | sliceType, ok := left.([]interface{}) | ||
90 | if !ok { | ||
91 | if isSliceType(left) { | ||
92 | return intr.filterProjectionWithReflection(node, left) | ||
93 | } | ||
94 | return nil, nil | ||
95 | } | ||
96 | compareNode := node.children[2] | ||
97 | collected := []interface{}{} | ||
98 | for _, element := range sliceType { | ||
99 | result, err := intr.Execute(compareNode, element) | ||
100 | if err != nil { | ||
101 | return nil, err | ||
102 | } | ||
103 | if !isFalse(result) { | ||
104 | current, err := intr.Execute(node.children[1], element) | ||
105 | if err != nil { | ||
106 | return nil, err | ||
107 | } | ||
108 | if current != nil { | ||
109 | collected = append(collected, current) | ||
110 | } | ||
111 | } | ||
112 | } | ||
113 | return collected, nil | ||
114 | case ASTFlatten: | ||
115 | left, err := intr.Execute(node.children[0], value) | ||
116 | if err != nil { | ||
117 | return nil, nil | ||
118 | } | ||
119 | sliceType, ok := left.([]interface{}) | ||
120 | if !ok { | ||
121 | // If we can't type convert to []interface{}, there's | ||
122 | // a chance this could still work via reflection if we're | ||
123 | // dealing with user provided types. | ||
124 | if isSliceType(left) { | ||
125 | return intr.flattenWithReflection(left) | ||
126 | } | ||
127 | return nil, nil | ||
128 | } | ||
129 | flattened := []interface{}{} | ||
130 | for _, element := range sliceType { | ||
131 | if elementSlice, ok := element.([]interface{}); ok { | ||
132 | flattened = append(flattened, elementSlice...) | ||
133 | } else if isSliceType(element) { | ||
134 | reflectFlat := []interface{}{} | ||
135 | v := reflect.ValueOf(element) | ||
136 | for i := 0; i < v.Len(); i++ { | ||
137 | reflectFlat = append(reflectFlat, v.Index(i).Interface()) | ||
138 | } | ||
139 | flattened = append(flattened, reflectFlat...) | ||
140 | } else { | ||
141 | flattened = append(flattened, element) | ||
142 | } | ||
143 | } | ||
144 | return flattened, nil | ||
145 | case ASTIdentity, ASTCurrentNode: | ||
146 | return value, nil | ||
147 | case ASTIndex: | ||
148 | if sliceType, ok := value.([]interface{}); ok { | ||
149 | index := node.value.(int) | ||
150 | if index < 0 { | ||
151 | index += len(sliceType) | ||
152 | } | ||
153 | if index < len(sliceType) && index >= 0 { | ||
154 | return sliceType[index], nil | ||
155 | } | ||
156 | return nil, nil | ||
157 | } | ||
158 | // Otherwise try via reflection. | ||
159 | rv := reflect.ValueOf(value) | ||
160 | if rv.Kind() == reflect.Slice { | ||
161 | index := node.value.(int) | ||
162 | if index < 0 { | ||
163 | index += rv.Len() | ||
164 | } | ||
165 | if index < rv.Len() && index >= 0 { | ||
166 | v := rv.Index(index) | ||
167 | return v.Interface(), nil | ||
168 | } | ||
169 | } | ||
170 | return nil, nil | ||
171 | case ASTKeyValPair: | ||
172 | return intr.Execute(node.children[0], value) | ||
173 | case ASTLiteral: | ||
174 | return node.value, nil | ||
175 | case ASTMultiSelectHash: | ||
176 | if value == nil { | ||
177 | return nil, nil | ||
178 | } | ||
179 | collected := make(map[string]interface{}) | ||
180 | for _, child := range node.children { | ||
181 | current, err := intr.Execute(child, value) | ||
182 | if err != nil { | ||
183 | return nil, err | ||
184 | } | ||
185 | key := child.value.(string) | ||
186 | collected[key] = current | ||
187 | } | ||
188 | return collected, nil | ||
189 | case ASTMultiSelectList: | ||
190 | if value == nil { | ||
191 | return nil, nil | ||
192 | } | ||
193 | collected := []interface{}{} | ||
194 | for _, child := range node.children { | ||
195 | current, err := intr.Execute(child, value) | ||
196 | if err != nil { | ||
197 | return nil, err | ||
198 | } | ||
199 | collected = append(collected, current) | ||
200 | } | ||
201 | return collected, nil | ||
202 | case ASTOrExpression: | ||
203 | matched, err := intr.Execute(node.children[0], value) | ||
204 | if err != nil { | ||
205 | return nil, err | ||
206 | } | ||
207 | if isFalse(matched) { | ||
208 | matched, err = intr.Execute(node.children[1], value) | ||
209 | if err != nil { | ||
210 | return nil, err | ||
211 | } | ||
212 | } | ||
213 | return matched, nil | ||
214 | case ASTAndExpression: | ||
215 | matched, err := intr.Execute(node.children[0], value) | ||
216 | if err != nil { | ||
217 | return nil, err | ||
218 | } | ||
219 | if isFalse(matched) { | ||
220 | return matched, nil | ||
221 | } | ||
222 | return intr.Execute(node.children[1], value) | ||
223 | case ASTNotExpression: | ||
224 | matched, err := intr.Execute(node.children[0], value) | ||
225 | if err != nil { | ||
226 | return nil, err | ||
227 | } | ||
228 | if isFalse(matched) { | ||
229 | return true, nil | ||
230 | } | ||
231 | return false, nil | ||
232 | case ASTPipe: | ||
233 | result := value | ||
234 | var err error | ||
235 | for _, child := range node.children { | ||
236 | result, err = intr.Execute(child, result) | ||
237 | if err != nil { | ||
238 | return nil, err | ||
239 | } | ||
240 | } | ||
241 | return result, nil | ||
242 | case ASTProjection: | ||
243 | left, err := intr.Execute(node.children[0], value) | ||
244 | if err != nil { | ||
245 | return nil, err | ||
246 | } | ||
247 | sliceType, ok := left.([]interface{}) | ||
248 | if !ok { | ||
249 | if isSliceType(left) { | ||
250 | return intr.projectWithReflection(node, left) | ||
251 | } | ||
252 | return nil, nil | ||
253 | } | ||
254 | collected := []interface{}{} | ||
255 | var current interface{} | ||
256 | for _, element := range sliceType { | ||
257 | current, err = intr.Execute(node.children[1], element) | ||
258 | if err != nil { | ||
259 | return nil, err | ||
260 | } | ||
261 | if current != nil { | ||
262 | collected = append(collected, current) | ||
263 | } | ||
264 | } | ||
265 | return collected, nil | ||
266 | case ASTSubexpression, ASTIndexExpression: | ||
267 | left, err := intr.Execute(node.children[0], value) | ||
268 | if err != nil { | ||
269 | return nil, err | ||
270 | } | ||
271 | return intr.Execute(node.children[1], left) | ||
272 | case ASTSlice: | ||
273 | sliceType, ok := value.([]interface{}) | ||
274 | if !ok { | ||
275 | if isSliceType(value) { | ||
276 | return intr.sliceWithReflection(node, value) | ||
277 | } | ||
278 | return nil, nil | ||
279 | } | ||
280 | parts := node.value.([]*int) | ||
281 | sliceParams := make([]sliceParam, 3) | ||
282 | for i, part := range parts { | ||
283 | if part != nil { | ||
284 | sliceParams[i].Specified = true | ||
285 | sliceParams[i].N = *part | ||
286 | } | ||
287 | } | ||
288 | return slice(sliceType, sliceParams) | ||
289 | case ASTValueProjection: | ||
290 | left, err := intr.Execute(node.children[0], value) | ||
291 | if err != nil { | ||
292 | return nil, nil | ||
293 | } | ||
294 | mapType, ok := left.(map[string]interface{}) | ||
295 | if !ok { | ||
296 | return nil, nil | ||
297 | } | ||
298 | values := make([]interface{}, len(mapType)) | ||
299 | for _, value := range mapType { | ||
300 | values = append(values, value) | ||
301 | } | ||
302 | collected := []interface{}{} | ||
303 | for _, element := range values { | ||
304 | current, err := intr.Execute(node.children[1], element) | ||
305 | if err != nil { | ||
306 | return nil, err | ||
307 | } | ||
308 | if current != nil { | ||
309 | collected = append(collected, current) | ||
310 | } | ||
311 | } | ||
312 | return collected, nil | ||
313 | } | ||
314 | return nil, errors.New("Unknown AST node: " + node.nodeType.String()) | ||
315 | } | ||
316 | |||
317 | func (intr *treeInterpreter) fieldFromStruct(key string, value interface{}) (interface{}, error) { | ||
318 | rv := reflect.ValueOf(value) | ||
319 | first, n := utf8.DecodeRuneInString(key) | ||
320 | fieldName := string(unicode.ToUpper(first)) + key[n:] | ||
321 | if rv.Kind() == reflect.Struct { | ||
322 | v := rv.FieldByName(fieldName) | ||
323 | if !v.IsValid() { | ||
324 | return nil, nil | ||
325 | } | ||
326 | return v.Interface(), nil | ||
327 | } else if rv.Kind() == reflect.Ptr { | ||
328 | // Handle multiple levels of indirection? | ||
329 | if rv.IsNil() { | ||
330 | return nil, nil | ||
331 | } | ||
332 | rv = rv.Elem() | ||
333 | v := rv.FieldByName(fieldName) | ||
334 | if !v.IsValid() { | ||
335 | return nil, nil | ||
336 | } | ||
337 | return v.Interface(), nil | ||
338 | } | ||
339 | return nil, nil | ||
340 | } | ||
341 | |||
342 | func (intr *treeInterpreter) flattenWithReflection(value interface{}) (interface{}, error) { | ||
343 | v := reflect.ValueOf(value) | ||
344 | flattened := []interface{}{} | ||
345 | for i := 0; i < v.Len(); i++ { | ||
346 | element := v.Index(i).Interface() | ||
347 | if reflect.TypeOf(element).Kind() == reflect.Slice { | ||
348 | // Then insert the contents of the element | ||
349 | // slice into the flattened slice, | ||
350 | // i.e flattened = append(flattened, mySlice...) | ||
351 | elementV := reflect.ValueOf(element) | ||
352 | for j := 0; j < elementV.Len(); j++ { | ||
353 | flattened = append( | ||
354 | flattened, elementV.Index(j).Interface()) | ||
355 | } | ||
356 | } else { | ||
357 | flattened = append(flattened, element) | ||
358 | } | ||
359 | } | ||
360 | return flattened, nil | ||
361 | } | ||
362 | |||
363 | func (intr *treeInterpreter) sliceWithReflection(node ASTNode, value interface{}) (interface{}, error) { | ||
364 | v := reflect.ValueOf(value) | ||
365 | parts := node.value.([]*int) | ||
366 | sliceParams := make([]sliceParam, 3) | ||
367 | for i, part := range parts { | ||
368 | if part != nil { | ||
369 | sliceParams[i].Specified = true | ||
370 | sliceParams[i].N = *part | ||
371 | } | ||
372 | } | ||
373 | final := []interface{}{} | ||
374 | for i := 0; i < v.Len(); i++ { | ||
375 | element := v.Index(i).Interface() | ||
376 | final = append(final, element) | ||
377 | } | ||
378 | return slice(final, sliceParams) | ||
379 | } | ||
380 | |||
381 | func (intr *treeInterpreter) filterProjectionWithReflection(node ASTNode, value interface{}) (interface{}, error) { | ||
382 | compareNode := node.children[2] | ||
383 | collected := []interface{}{} | ||
384 | v := reflect.ValueOf(value) | ||
385 | for i := 0; i < v.Len(); i++ { | ||
386 | element := v.Index(i).Interface() | ||
387 | result, err := intr.Execute(compareNode, element) | ||
388 | if err != nil { | ||
389 | return nil, err | ||
390 | } | ||
391 | if !isFalse(result) { | ||
392 | current, err := intr.Execute(node.children[1], element) | ||
393 | if err != nil { | ||
394 | return nil, err | ||
395 | } | ||
396 | if current != nil { | ||
397 | collected = append(collected, current) | ||
398 | } | ||
399 | } | ||
400 | } | ||
401 | return collected, nil | ||
402 | } | ||
403 | |||
404 | func (intr *treeInterpreter) projectWithReflection(node ASTNode, value interface{}) (interface{}, error) { | ||
405 | collected := []interface{}{} | ||
406 | v := reflect.ValueOf(value) | ||
407 | for i := 0; i < v.Len(); i++ { | ||
408 | element := v.Index(i).Interface() | ||
409 | result, err := intr.Execute(node.children[1], element) | ||
410 | if err != nil { | ||
411 | return nil, err | ||
412 | } | ||
413 | if result != nil { | ||
414 | collected = append(collected, result) | ||
415 | } | ||
416 | } | ||
417 | return collected, nil | ||
418 | } | ||