[connector/routing] Fix config validation with context other than resource (open-telemetry#37411)

<!--Ex. Fixing a bug - Describe the bug and how this fixes the issue.
Ex. Adding a feature - Explain what this achieves.-->
#### Description
Remove a residual fallthrough keyword which induce a configuration error

<!-- Issue number (e.g. open-telemetry#1234) or full URL to issue, if applicable. -->
#### Link to tracking issue
Fixes open-telemetry#37410

---------

Co-authored-by: Andrzej Stencel <[email protected]>

Author: 2 people

.chloggen/fix-routing-connector-context-regression.yaml

@@ -0,0 +1,27 @@
+# Use this changelog template to create an entry for release notes.
+
+# One of 'breaking', 'deprecation', 'new_component', 'enhancement', 'bug_fix'
+change_type: bug_fix
+
+# The name of the component, or a single word describing the area of concern, (e.g. filelogreceiver)
+component: connector/routing
+
+# A brief description of the change.  Surround your text with quotes ("") if it needs to start with a backtick (`).
+note: Fix config validation with context other than `resource`
+
+# Mandatory: One or more tracking issues related to the change. You can use the PR number here if no issue exists.
+issues: [37410]
+
+# (Optional) One or more lines of additional information to render under the primary note.
+# These lines will be padded with 2 spaces and then inserted directly into the document.
+# Use pipe (|) for multiline entries.
+subtext:
+
+# If your change doesn't affect end users or the exported elements of any package,
+# you should instead start your pull request title with [chore] or use the "Skip Changelog" label.
+# Optional: The change log or logs in which this entry should be included.
+# e.g. '[user]' or '[user, api]'
+# Include 'user' if the change is relevant to end users.
+# Include 'api' if there is a change to a library API.
+# Default: '[user]'
+change_logs: []

connector/routingconnector/config.go

@@ -65,15 +65,14 @@ func (c *Config) Validate() error {
 		}
 
 		switch item.Context {
-		case "", "resource": // ok
+		case "", "resource", "span", "metric", "datapoint", "log": // ok
 		case "request":
 			if item.Statement != "" || item.Condition == "" {
 				return fmt.Errorf("%q context requires a 'condition'", item.Context)
 			}
 			if _, err := parseRequestCondition(item.Condition); err != nil {
 				return err
 			}
-			fallthrough
 		default:
 			return errors.New("invalid context: " + item.Context)
 		}

connector/routingconnector/config_test.go

@@ -233,6 +233,20 @@ func TestValidateConfig(t *testing.T) {
 			},
 			error: `"request" context requires a 'condition'`,
 		},
+		{
+			name: "request context with condition",
+			config: &Config{
+				Table: []RoutingTableItem{
+					{
+						Context:   "request",
+						Condition: `request["attr"] == "acme"`,
+						Pipelines: []pipeline.ID{
+							pipeline.NewIDWithName(pipeline.SignalTraces, "otlp"),
+						},
+					},
+				},
+			},
+		},
 		{
 			name: "request context with invalid condition",
 			config: &Config{
@@ -248,6 +262,118 @@ func TestValidateConfig(t *testing.T) {
 			},
 			error: `condition must have format 'request["<name>"] <comparator> <value>'`,
 		},
+		{
+			name: "span context with statement",
+			config: &Config{
+				Table: []RoutingTableItem{
+					{
+						Context:   "span",
+						Statement: `route() where attributes["attr"] == "acme"`,
+						Pipelines: []pipeline.ID{
+							pipeline.NewIDWithName(pipeline.SignalTraces, "otlp"),
+						},
+					},
+				},
+			},
+		},
+		{
+			name: "span context with condition",
+			config: &Config{
+				Table: []RoutingTableItem{
+					{
+						Context:   "span",
+						Condition: `attributes["attr"] == "acme"`,
+						Pipelines: []pipeline.ID{
+							pipeline.NewIDWithName(pipeline.SignalTraces, "otlp"),
+						},
+					},
+				},
+			},
+		},
+		{
+			name: "metric context with statement",
+			config: &Config{
+				Table: []RoutingTableItem{
+					{
+						Context:   "metric",
+						Statement: `route() where instrumentation_scope.attributes["attr"] == "acme"`,
+						Pipelines: []pipeline.ID{
+							pipeline.NewIDWithName(pipeline.SignalTraces, "otlp"),
+						},
+					},
+				},
+			},
+		},
+		{
+			name: "metric context with condition",
+			config: &Config{
+				Table: []RoutingTableItem{
+					{
+						Context:   "metric",
+						Condition: `instrumentation_scope.attributes["attr"] == "acme"`,
+						Pipelines: []pipeline.ID{
+							pipeline.NewIDWithName(pipeline.SignalTraces, "otlp"),
+						},
+					},
+				},
+			},
+		},
+		{
+			name: "datapoint context with statement",
+			config: &Config{
+				Table: []RoutingTableItem{
+					{
+						Context:   "datapoint",
+						Statement: `route() where attributes["attr"] == "acme"`,
+						Pipelines: []pipeline.ID{
+							pipeline.NewIDWithName(pipeline.SignalTraces, "otlp"),
+						},
+					},
+				},
+			},
+		},
+		{
+			name: "datapoint context with condition",
+			config: &Config{
+				Table: []RoutingTableItem{
+					{
+						Context:   "datapoint",
+						Condition: `attributes["attr"] == "acme"`,
+						Pipelines: []pipeline.ID{
+							pipeline.NewIDWithName(pipeline.SignalTraces, "otlp"),
+						},
+					},
+				},
+			},
+		},
+		{
+			name: "log context with statement",
+			config: &Config{
+				Table: []RoutingTableItem{
+					{
+						Context:   "log",
+						Statement: `route() where attributes["attr"] == "acme"`,
+						Pipelines: []pipeline.ID{
+							pipeline.NewIDWithName(pipeline.SignalTraces, "otlp"),
+						},
+					},
+				},
+			},
+		},
+		{
+			name: "log context with condition",
+			config: &Config{
+				Table: []RoutingTableItem{
+					{
+						Context:   "log",
+						Condition: `attributes["attr"] == "acme"`,
+						Pipelines: []pipeline.ID{
+							pipeline.NewIDWithName(pipeline.SignalTraces, "otlp"),
+						},
+					},
+				},
+			},
+		},
 	}
 
 	for _, tt := range tests {