planner_graph.go 17 KB

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  1. // Copyright 2022-2023 EMQ Technologies Co., Ltd.
  2. //
  3. // Licensed under the Apache License, Version 2.0 (the "License");
  4. // you may not use this file except in compliance with the License.
  5. // You may obtain a copy of the License at
  6. //
  7. // http://www.apache.org/licenses/LICENSE-2.0
  8. //
  9. // Unless required by applicable law or agreed to in writing, software
  10. // distributed under the License is distributed on an "AS IS" BASIS,
  11. // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  12. // See the License for the specific language governing permissions and
  13. // limitations under the License.
  14. package planner
  15. import (
  16. "errors"
  17. "fmt"
  18. "github.com/lf-edge/ekuiper/internal/binder/function"
  19. "github.com/lf-edge/ekuiper/internal/topo"
  20. "github.com/lf-edge/ekuiper/internal/topo/graph"
  21. "github.com/lf-edge/ekuiper/internal/topo/node"
  22. "github.com/lf-edge/ekuiper/internal/topo/operator"
  23. "github.com/lf-edge/ekuiper/internal/xsql"
  24. "github.com/lf-edge/ekuiper/pkg/api"
  25. "github.com/lf-edge/ekuiper/pkg/ast"
  26. "github.com/lf-edge/ekuiper/pkg/cast"
  27. "github.com/lf-edge/ekuiper/pkg/message"
  28. "strings"
  29. )
  30. type genNodeFunc func(name string, props map[string]interface{}, options *api.RuleOption) (api.TopNode, error)
  31. var extNodes = map[string]genNodeFunc{}
  32. // PlanByGraph returns a topo.Topo object by a graph
  33. func PlanByGraph(rule *api.Rule) (*topo.Topo, error) {
  34. ruleGraph := rule.Graph
  35. if ruleGraph == nil {
  36. return nil, errors.New("no graph")
  37. }
  38. tp, err := topo.NewWithNameAndQos(rule.Id, rule.Options.Qos, rule.Options.CheckpointInterval)
  39. if err != nil {
  40. return nil, err
  41. }
  42. var (
  43. nodeMap = make(map[string]api.TopNode)
  44. sinks = make(map[string]bool)
  45. sources = make(map[string]bool)
  46. )
  47. for nodeName, gn := range ruleGraph.Nodes {
  48. switch gn.Type {
  49. case "source":
  50. if _, ok := ruleGraph.Topo.Edges[nodeName]; !ok {
  51. return nil, fmt.Errorf("no edge defined for source node %s", nodeName)
  52. }
  53. sourceType, ok := gn.Props["source_type"]
  54. if !ok {
  55. sourceType = "stream"
  56. }
  57. st, ok := sourceType.(string)
  58. if !ok {
  59. return nil, fmt.Errorf("source_type %v is not string", sourceType)
  60. }
  61. st = strings.ToLower(st)
  62. sourceOption := &ast.Options{}
  63. err := cast.MapToStruct(gn.Props, sourceOption)
  64. if err != nil {
  65. return nil, err
  66. }
  67. sourceOption.TYPE = gn.NodeType
  68. switch st {
  69. case "stream":
  70. // TODO deal with conf key
  71. pp, err := operator.NewPreprocessor(true, nil, true, nil, rule.Options.IsEventTime, sourceOption.TIMESTAMP, sourceOption.TIMESTAMP_FORMAT, strings.EqualFold(sourceOption.FORMAT, message.FormatBinary), sourceOption.STRICT_VALIDATION)
  72. if err != nil {
  73. return nil, err
  74. }
  75. srcNode := node.NewSourceNode(nodeName, ast.TypeStream, pp, sourceOption, rule.Options.SendError)
  76. nodeMap[nodeName] = srcNode
  77. tp.AddSrc(srcNode)
  78. case "table":
  79. // TODO add table
  80. return nil, fmt.Errorf("table source is not supported yet")
  81. default:
  82. return nil, fmt.Errorf("unknown source type %s", st)
  83. }
  84. sources[nodeName] = true
  85. case "sink":
  86. if _, ok := ruleGraph.Topo.Edges[nodeName]; ok {
  87. return nil, fmt.Errorf("sink %s has edge", nodeName)
  88. }
  89. nodeMap[nodeName] = node.NewSinkNode(nodeName, gn.NodeType, gn.Props)
  90. sinks[nodeName] = true
  91. case "operator":
  92. if _, ok := ruleGraph.Topo.Edges[nodeName]; !ok {
  93. return nil, fmt.Errorf("no edge defined for operator node %s", nodeName)
  94. }
  95. nt := strings.ToLower(gn.NodeType)
  96. switch nt {
  97. case "function":
  98. fop, err := parseFunc(gn.Props)
  99. if err != nil {
  100. return nil, err
  101. }
  102. op := Transform(fop, nodeName, rule.Options)
  103. nodeMap[nodeName] = op
  104. case "aggfunc":
  105. fop, err := parseFunc(gn.Props)
  106. if err != nil {
  107. return nil, err
  108. }
  109. fop.IsAgg = true
  110. op := Transform(fop, nodeName, rule.Options)
  111. nodeMap[nodeName] = op
  112. case "filter":
  113. fop, err := parseFilter(gn.Props)
  114. if err != nil {
  115. return nil, err
  116. }
  117. op := Transform(fop, nodeName, rule.Options)
  118. nodeMap[nodeName] = op
  119. case "pick":
  120. pop, err := parsePick(gn.Props)
  121. if err != nil {
  122. return nil, err
  123. }
  124. op := Transform(pop, nodeName, rule.Options)
  125. nodeMap[nodeName] = op
  126. case "window":
  127. wconf, err := parseWindow(gn.Props)
  128. if err != nil {
  129. return nil, err
  130. }
  131. op, err := node.NewWindowOp(nodeName, *wconf, ruleGraph.Topo.Sources, rule.Options)
  132. if err != nil {
  133. return nil, err
  134. }
  135. nodeMap[nodeName] = op
  136. case "join":
  137. jop, err := parseJoin(gn.Props)
  138. if err != nil {
  139. return nil, err
  140. }
  141. op := Transform(jop, nodeName, rule.Options)
  142. nodeMap[nodeName] = op
  143. case "groupby":
  144. gop, err := parseGroupBy(gn.Props)
  145. if err != nil {
  146. return nil, err
  147. }
  148. op := Transform(gop, nodeName, rule.Options)
  149. nodeMap[nodeName] = op
  150. case "orderby":
  151. oop, err := parseOrderBy(gn.Props)
  152. if err != nil {
  153. return nil, err
  154. }
  155. op := Transform(oop, nodeName, rule.Options)
  156. nodeMap[nodeName] = op
  157. case "switch":
  158. sconf, err := parseSwitch(gn.Props)
  159. if err != nil {
  160. return nil, fmt.Errorf("parse switch %s error: %v", nodeName, err)
  161. }
  162. op, err := node.NewSwitchNode(nodeName, sconf, rule.Options)
  163. if err != nil {
  164. return nil, fmt.Errorf("create switch %s error: %v", nodeName, err)
  165. }
  166. nodeMap[nodeName] = op
  167. default:
  168. gnf, ok := extNodes[nt]
  169. if !ok {
  170. return nil, fmt.Errorf("unknown operator type %s", gn.NodeType)
  171. }
  172. op, err := gnf(nodeName, gn.Props, rule.Options)
  173. if err != nil {
  174. return nil, err
  175. }
  176. nodeMap[nodeName] = op
  177. }
  178. default:
  179. return nil, fmt.Errorf("unknown node type %s", gn.Type)
  180. }
  181. }
  182. // validate source node
  183. for _, nodeName := range ruleGraph.Topo.Sources {
  184. if _, ok := sources[nodeName]; !ok {
  185. return nil, fmt.Errorf("source %s is not a source type node", nodeName)
  186. }
  187. }
  188. // reverse edges, value is a 2-dim array. Only switch node will have the second dim
  189. reversedEdges := make(map[string][][]string)
  190. rclone := make(map[string][]string)
  191. for fromNode, toNodes := range ruleGraph.Topo.Edges {
  192. if _, ok := ruleGraph.Nodes[fromNode]; !ok {
  193. return nil, fmt.Errorf("node %s is not defined", fromNode)
  194. }
  195. for i, toNode := range toNodes {
  196. switch tn := toNode.(type) {
  197. case string:
  198. if _, ok := ruleGraph.Nodes[tn]; !ok {
  199. return nil, fmt.Errorf("node %s is not defined", tn)
  200. }
  201. if _, ok := reversedEdges[tn]; !ok {
  202. reversedEdges[tn] = make([][]string, 1)
  203. }
  204. reversedEdges[tn][0] = append(reversedEdges[tn][0], fromNode)
  205. rclone[tn] = append(rclone[tn], fromNode)
  206. case []interface{}:
  207. for _, tni := range tn {
  208. tnn, ok := tni.(string)
  209. if !ok { // never happen
  210. return nil, fmt.Errorf("invalid edge toNode %v", toNode)
  211. }
  212. if _, ok := ruleGraph.Nodes[tnn]; !ok {
  213. return nil, fmt.Errorf("node %s is not defined", tnn)
  214. }
  215. for len(reversedEdges[tnn]) <= i {
  216. reversedEdges[tnn] = append(reversedEdges[tnn], []string{})
  217. }
  218. reversedEdges[tnn][i] = append(reversedEdges[tnn][i], fromNode)
  219. rclone[tnn] = append(rclone[tnn], fromNode)
  220. }
  221. }
  222. }
  223. }
  224. // sort the nodes by topological order
  225. nodesInOrder := make([]string, len(ruleGraph.Nodes))
  226. i := 0
  227. genNodesInOrder(ruleGraph.Topo.Sources, ruleGraph.Topo.Edges, rclone, nodesInOrder, i)
  228. // validate the typo
  229. // the map is to record the output for each node
  230. dataFlow := make(map[string]*graph.IOType)
  231. for _, n := range nodesInOrder {
  232. gn := ruleGraph.Nodes[n]
  233. if gn == nil {
  234. return nil, fmt.Errorf("can't find node %s", n)
  235. }
  236. if gn.Type == "source" {
  237. dataFlow[n] = &graph.IOType{
  238. Type: graph.IOINPUT_TYPE_ROW,
  239. RowType: graph.IOROW_TYPE_SINGLE,
  240. CollectionType: graph.IOCOLLECTION_TYPE_ANY,
  241. AllowMulti: false,
  242. }
  243. } else if gn.Type == "sink" {
  244. continue
  245. } else {
  246. nodeIO, ok := graph.OpIO[strings.ToLower(gn.NodeType)]
  247. if !ok {
  248. return nil, fmt.Errorf("can't find the io definiton for node type %s", gn.NodeType)
  249. }
  250. dataInCondition := nodeIO[0]
  251. indim := reversedEdges[n]
  252. var innodes []string
  253. for _, in := range indim {
  254. innodes = append(innodes, in...)
  255. }
  256. if len(innodes) > 1 {
  257. if dataInCondition.AllowMulti {
  258. for _, innode := range innodes {
  259. _, err = graph.Fit(dataFlow[innode], dataInCondition)
  260. if err != nil {
  261. return nil, fmt.Errorf("node %s output does not match node %s input: %v", innode, n, err)
  262. }
  263. }
  264. } else {
  265. return nil, fmt.Errorf("operator %s of type %s does not allow multiple inputs", n, gn.NodeType)
  266. }
  267. } else if len(innodes) == 1 {
  268. _, err := graph.Fit(dataFlow[innodes[0]], dataInCondition)
  269. if err != nil {
  270. return nil, fmt.Errorf("node %s output does not match node %s input: %v", innodes[0], n, err)
  271. }
  272. } else {
  273. return nil, fmt.Errorf("operator %s of type %s has no input", n, gn.NodeType)
  274. }
  275. out := nodeIO[1]
  276. in := dataFlow[innodes[0]]
  277. dataFlow[n] = graph.MapOut(in, out)
  278. // convert filter to having if the input is aggregated
  279. if gn.NodeType == "filter" && in.Type == graph.IOINPUT_TYPE_COLLECTION && in.CollectionType == graph.IOCOLLECTION_TYPE_GROUPED {
  280. fop, err := parseHaving(gn.Props)
  281. if err != nil {
  282. return nil, err
  283. }
  284. op := Transform(fop, n, rule.Options)
  285. nodeMap[n] = op
  286. }
  287. }
  288. }
  289. // add the linkages
  290. for nodeName, fromNodes := range reversedEdges {
  291. totalLen := 0
  292. for _, fromNode := range fromNodes {
  293. totalLen += len(fromNode)
  294. }
  295. inputs := make([]api.Emitter, 0, totalLen)
  296. for i, fromNode := range fromNodes {
  297. for _, from := range fromNode {
  298. if i == 0 {
  299. inputs = append(inputs, nodeMap[from].(api.Emitter))
  300. } else {
  301. switch sn := nodeMap[from].(type) {
  302. case *node.SwitchNode:
  303. inputs = append(inputs, sn.GetEmitter(i))
  304. default:
  305. return nil, fmt.Errorf("node %s is not a switch node but have multiple output", from)
  306. }
  307. }
  308. }
  309. }
  310. n := nodeMap[nodeName]
  311. if n == nil {
  312. return nil, fmt.Errorf("node %s is not defined", nodeName)
  313. }
  314. if _, ok := sinks[nodeName]; ok {
  315. tp.AddSink(inputs, n.(*node.SinkNode))
  316. } else {
  317. tp.AddOperator(inputs, n.(node.OperatorNode))
  318. }
  319. }
  320. return tp, nil
  321. }
  322. func genNodesInOrder(toNodes []string, edges map[string][]interface{}, flatReversedEdges map[string][]string, nodesInOrder []string, i int) int {
  323. for _, src := range toNodes {
  324. if len(flatReversedEdges[src]) > 1 {
  325. flatReversedEdges[src] = flatReversedEdges[src][1:]
  326. continue
  327. }
  328. nodesInOrder[i] = src
  329. i++
  330. tns := make([]string, 0, len(edges[src]))
  331. for _, toNode := range edges[src] {
  332. switch toNode.(type) {
  333. case string:
  334. tns = append(tns, toNode.(string))
  335. case []interface{}:
  336. for _, tni := range toNode.([]interface{}) {
  337. tns = append(tns, tni.(string))
  338. }
  339. }
  340. }
  341. i = genNodesInOrder(tns, edges, flatReversedEdges, nodesInOrder, i)
  342. }
  343. return i
  344. }
  345. func parseOrderBy(props map[string]interface{}) (*operator.OrderOp, error) {
  346. n := &graph.Orderby{}
  347. err := cast.MapToStruct(props, n)
  348. if err != nil {
  349. return nil, err
  350. }
  351. stmt := "SELECT * FROM unknown ORDER BY"
  352. for _, s := range n.Sorts {
  353. stmt += " " + s.Field + " "
  354. if s.Desc {
  355. stmt += "DESC"
  356. }
  357. }
  358. p, err := xsql.NewParser(strings.NewReader(stmt)).Parse()
  359. if err != nil {
  360. return nil, fmt.Errorf("invalid order by statement error: %v", err)
  361. }
  362. if len(p.SortFields) == 0 {
  363. return nil, fmt.Errorf("order by statement is empty")
  364. }
  365. return &operator.OrderOp{
  366. SortFields: p.SortFields,
  367. }, nil
  368. }
  369. func parseGroupBy(props map[string]interface{}) (*operator.AggregateOp, error) {
  370. n := &graph.Groupby{}
  371. err := cast.MapToStruct(props, n)
  372. if err != nil {
  373. return nil, err
  374. }
  375. if len(n.Dimensions) == 0 {
  376. return nil, fmt.Errorf("groupby must have at least one dimension")
  377. }
  378. stmt := "SELECT * FROM unknown Group By " + strings.Join(n.Dimensions, ",")
  379. p, err := xsql.NewParser(strings.NewReader(stmt)).Parse()
  380. if err != nil {
  381. return nil, fmt.Errorf("invalid join statement error: %v", err)
  382. }
  383. return &operator.AggregateOp{Dimensions: p.Dimensions}, nil
  384. }
  385. func parseJoin(props map[string]interface{}) (*operator.JoinOp, error) {
  386. n := &graph.Join{}
  387. err := cast.MapToStruct(props, n)
  388. if err != nil {
  389. return nil, err
  390. }
  391. stmt := "SELECT * FROM " + n.From
  392. for _, join := range n.Joins {
  393. stmt += " " + join.Type + " JOIN ON " + join.On
  394. }
  395. p, err := xsql.NewParser(strings.NewReader(stmt)).Parse()
  396. if err != nil {
  397. return nil, fmt.Errorf("invalid join statement error: %v", err)
  398. }
  399. return &operator.JoinOp{Joins: p.Joins, From: p.Sources[0].(*ast.Table)}, nil
  400. }
  401. func parseWindow(props map[string]interface{}) (*node.WindowConfig, error) {
  402. n := &graph.Window{}
  403. err := cast.MapToStruct(props, n)
  404. if err != nil {
  405. return nil, err
  406. }
  407. if n.Size <= 0 {
  408. return nil, fmt.Errorf("window size %d is invalid", n.Size)
  409. }
  410. var (
  411. wt ast.WindowType
  412. length int
  413. interval int
  414. )
  415. switch strings.ToLower(n.Type) {
  416. case "tumblingwindow":
  417. wt = ast.TUMBLING_WINDOW
  418. if n.Interval != 0 && n.Interval != n.Size {
  419. return nil, fmt.Errorf("tumbling window interval must equal to size")
  420. }
  421. case "hoppingwindow":
  422. wt = ast.HOPPING_WINDOW
  423. if n.Interval <= 0 {
  424. return nil, fmt.Errorf("hopping window interval must be greater than 0")
  425. }
  426. if n.Interval > n.Size {
  427. return nil, fmt.Errorf("hopping window interval must be less than size")
  428. }
  429. case "sessionwindow":
  430. wt = ast.SESSION_WINDOW
  431. if n.Interval <= 0 {
  432. return nil, fmt.Errorf("hopping window interval must be greater than 0")
  433. }
  434. case "slidingwindow":
  435. wt = ast.SLIDING_WINDOW
  436. if n.Interval != 0 && n.Interval != n.Size {
  437. return nil, fmt.Errorf("tumbling window interval must equal to size")
  438. }
  439. case "countwindow":
  440. wt = ast.COUNT_WINDOW
  441. if n.Interval < 0 {
  442. return nil, fmt.Errorf("count window interval must be greater or equal to 0")
  443. }
  444. if n.Interval > n.Size {
  445. return nil, fmt.Errorf("count window interval must be less than size")
  446. }
  447. if n.Interval == 0 {
  448. n.Interval = n.Size
  449. }
  450. default:
  451. return nil, fmt.Errorf("unknown window type %s", n.Type)
  452. }
  453. if wt == ast.COUNT_WINDOW {
  454. length = n.Size
  455. interval = n.Interval
  456. } else {
  457. var unit = 1
  458. switch strings.ToLower(n.Unit) {
  459. case "dd":
  460. unit = 24 * 3600 * 1000
  461. case "hh":
  462. unit = 3600 * 1000
  463. case "mi":
  464. unit = 60 * 1000
  465. case "ss":
  466. unit = 1000
  467. case "ms":
  468. unit = 1
  469. default:
  470. return nil, fmt.Errorf("Invalid unit %s", n.Unit)
  471. }
  472. length = n.Size * unit
  473. interval = n.Interval * unit
  474. }
  475. return &node.WindowConfig{
  476. Type: wt,
  477. Length: length,
  478. Interval: interval,
  479. }, nil
  480. }
  481. func parsePick(props map[string]interface{}) (*operator.ProjectOp, error) {
  482. n := &graph.Select{}
  483. err := cast.MapToStruct(props, n)
  484. if err != nil {
  485. return nil, err
  486. }
  487. stmt, err := xsql.NewParser(strings.NewReader("select " + strings.Join(n.Fields, ",") + " from nonexist")).Parse()
  488. if err != nil {
  489. return nil, err
  490. }
  491. t := ProjectPlan{
  492. fields: stmt.Fields,
  493. isAggregate: xsql.IsAggStatement(stmt),
  494. }.Init()
  495. return &operator.ProjectOp{ColNames: t.colNames, AliasNames: t.aliasNames, AliasFields: t.aliasFields, ExprFields: t.exprFields, IsAggregate: t.isAggregate, AllWildcard: t.allWildcard, WildcardEmitters: t.wildcardEmitters, ExprNames: t.exprNames, SendMeta: t.sendMeta}, nil
  496. }
  497. func parseFunc(props map[string]interface{}) (*operator.FuncOp, error) {
  498. m, ok := props["expr"]
  499. if !ok {
  500. return nil, errors.New("no expr")
  501. }
  502. funcExpr, ok := m.(string)
  503. if !ok {
  504. return nil, fmt.Errorf("expr %v is not string", m)
  505. }
  506. stmt, err := xsql.NewParser(strings.NewReader("select " + funcExpr + " from nonexist")).Parse()
  507. if err != nil {
  508. return nil, err
  509. }
  510. f := stmt.Fields[0]
  511. c, ok := f.Expr.(*ast.Call)
  512. if !ok {
  513. // never happen
  514. return nil, fmt.Errorf("expr %s is not ast.Call", funcExpr)
  515. }
  516. var name string
  517. if f.AName != "" {
  518. name = f.AName
  519. } else {
  520. name = f.Name
  521. }
  522. return &operator.FuncOp{CallExpr: c, Name: name, IsAgg: function.IsAggFunc(name)}, nil
  523. }
  524. func parseFilter(props map[string]interface{}) (*operator.FilterOp, error) {
  525. m, ok := props["expr"]
  526. if !ok {
  527. return nil, errors.New("no expr")
  528. }
  529. conditionExpr, ok := m.(string)
  530. if !ok {
  531. return nil, fmt.Errorf("expr %v is not string", m)
  532. }
  533. p := xsql.NewParser(strings.NewReader("where " + conditionExpr))
  534. if exp, err := p.ParseCondition(); err != nil {
  535. return nil, err
  536. } else {
  537. if exp != nil {
  538. return &operator.FilterOp{Condition: exp}, nil
  539. }
  540. }
  541. return nil, fmt.Errorf("expr %v is not a condition", m)
  542. }
  543. func parseHaving(props map[string]interface{}) (*operator.HavingOp, error) {
  544. m, ok := props["expr"]
  545. if !ok {
  546. return nil, errors.New("no expr")
  547. }
  548. conditionExpr, ok := m.(string)
  549. if !ok {
  550. return nil, fmt.Errorf("expr %v is not string", m)
  551. }
  552. p := xsql.NewParser(strings.NewReader("where " + conditionExpr))
  553. if exp, err := p.ParseCondition(); err != nil {
  554. return nil, err
  555. } else {
  556. if exp != nil {
  557. return &operator.HavingOp{Condition: exp}, nil
  558. }
  559. }
  560. return nil, fmt.Errorf("expr %v is not a condition", m)
  561. }
  562. func parseSwitch(props map[string]interface{}) (*node.SwitchConfig, error) {
  563. n := &graph.Switch{}
  564. err := cast.MapToStruct(props, n)
  565. if err != nil {
  566. return nil, err
  567. }
  568. if len(n.Cases) == 0 {
  569. return nil, fmt.Errorf("switch node must have at least one case")
  570. }
  571. caseExprs := make([]ast.Expr, len(n.Cases))
  572. for i, c := range n.Cases {
  573. p := xsql.NewParser(strings.NewReader("where " + c))
  574. if exp, err := p.ParseCondition(); err != nil {
  575. return nil, fmt.Errorf("parse case %d error: %v", i, err)
  576. } else {
  577. if exp != nil {
  578. caseExprs[i] = exp
  579. }
  580. }
  581. }
  582. return &node.SwitchConfig{
  583. Cases: caseExprs,
  584. StopAtFirstMatch: n.StopAtFirstMatch,
  585. }, nil
  586. }