QL: Add preliminary support for structured logs

ql/ql/src/codeql_ql/StructuredLogs.qll

@@ -0,0 +1,132 @@
+private import ql
+private import codeql_ql.ast.internal.TreeSitter
+
+class Object extends JSON::Object {
+  JSON::Value getValue(string key) {
+    exists(JSON::Pair p |
+      p = this.getChild(_) and p.getKey().(JSON::String).getChild().getValue() = key
+    |
+      result = p.getValue()
+    )
+  }
+
+  string getString(string key) { result = this.getValue(key).(JSON::String).getChild().getValue() }
+
+  int getNumber(string key) { result = this.getValue(key).(JSON::Number).getValue().toInt() }
+
+  Array getArray(string key) { result = this.getValue(key) }
+
+  string getType() { result = this.getString("type") }
+
+  int getEventId() { result = this.getNumber("event_id") }
+
+  string getTime() { result = this.getString("time") }
+}
+
+class Array extends JSON::Array {
+  Object getObject(int i) { result = this.getChild(i) }
+
+  string getString(int i) { result = this.getChild(i).(JSON::String).getChild().getValue() }
+
+  int getNumber(int i) { result = this.getChild(i).(JSON::Number).getValue().toInt() }
+}
+
+abstract class LogEntry extends Object { }
+
+class LogHeader extends LogEntry {
+  LogHeader() { this.getType() = "LOG_HEADER" }
+
+  string getCodeQLVersion() { result = this.getString("codeqlVersion") }
+
+  string getLogVersion() { result = this.getString("logVersion") }
+}
+
+class QueryStarted extends LogEntry {
+  QueryStarted() { this.getType() = "QUERY_STARTED" }
+
+  string getQueryName() { result = this.getString("queryName") }
+
+  int getStage(int i) { result = this.getArray("stage").getNumber(i) }
+}
+
+class PredicateStarted extends LogEntry {
+  PredicateStarted() { this.getType() = "PREDICATE_STARTED" }
+
+  string getPredicateName() { result = this.getString("predicateName") }
+
+  string getPosition() { result = this.getString("position") }
+
+  string getPredicateType() { result = this.getString("predicateType") }
+
+  int getQueryCausingWork() { result = this.getNumber("queryCausingWork") }
+
+  string getRAHash() { result = this.getString("raHash") }
+
+  Object getRA() { result = this.getValue("ra") }
+}
+
+class PipelineStarted extends LogEntry {
+  PipelineStarted() { this.getType() = "PIPELINE_STARTED" }
+
+  int getPredicateStartEvent() { result = this.getNumber("predicateStartEvent") }
+
+  string getRAReference() { result = this.getString("raReference") }
+}
+
+class PipelineCompleted extends LogEntry {
+  PipelineCompleted() { this.getType() = "PIPELINE_COMPLETED" }
+
+  int getStartEvent() { result = this.getNumber("startEvent") }
+
+  string getRAReference() { result = this.getString("raReference") }
+
+  int getCount(int i) { result = this.getArray("counts").getNumber(i) }
+
+  int getDuplicationPercentage(int i) {
+    result = this.getArray("duplicationPercentages").getNumber(i)
+  }
+
+  int getResultSize() { result = this.getNumber("resultSize") }
+}
+
+class PredicateCompleted extends LogEntry {
+  PredicateCompleted() { this.getType() = "PREDICATE_COMPLETED" }
+
+  int getStartEvent() { result = this.getNumber("startEvent") }
+
+  int getResultSize() { result = this.getNumber("resultSize") }
+}
+
+class QueryCompleted extends LogEntry {
+  QueryCompleted() { this.getType() = "QUERY_COMPLETED" }
+
+  int getStartEvent() { result = this.getNumber("startEvent") }
+
+  string getTerminationType() { result = this.getString("terminationType") }
+}
+
+class LogFooter extends LogEntry {
+  LogFooter() { this.getType() = "LOG_FOOTER" }
+}
+
+class CacheLookup extends LogEntry {
+  CacheLookup() { this.getType() = "CACHE_LOOKUP" }
+
+  int getRelationSize() { result = this.getNumber("relationSize") }
+}
+
+class SentinelEmpty extends LogEntry {
+  SentinelEmpty() { this.getType() = "SENTINEL_EMPTY" }
+}
+
+// Stuff to test whether we've covered all event types
+private File logFile() { result = any(LogHeader h).getLocation().getFile() }
+
+private Object missing() {
+  result =
+    any(Object o |
+      o.getLocation().getFile() = logFile() and
+      not o instanceof LogEntry and
+      not exists(o.getParent().getParent()) // don't count nested objects
+    )
+}