[OTEL Infra Host Mapping ]datadog.host.use_as_metadata causes Panic

[atmask]

Problem When enabling the OTEL Infra Host Mapping functionality the OTEL Collector is thrown into a panic that originates from this module.

Config:

processors:
  transform/datadog:
    metric_statements: &statements
      - context: resource
        statements:
          - set(attributes["datadog.host.use_as_metadata"], true)
          - set(attributes["datadog.host.name"], <name>)
    log_statements: *statements
    trace_statements: *statements

exporters:
  datadog:
    hostname: <also try setting here>
    api: <ommiting>

Full Trace

panic: assignment to entry in nil map

goroutine 181 [running]:
github.com/DataDog/opentelemetry-mapping-go/pkg/inframetadata/internal/hostmap.(*HostMap).Update(0xc002e96e20, {0xc00252c570, 0x24}, {0xc003ff14b8?, 0xc003fa163c?})
	github.com/DataDog/opentelemetry-mapping-go/pkg/[email protected]/internal/hostmap/hostmap.go:243 +0x619
github.com/DataDog/opentelemetry-mapping-go/pkg/inframetadata.(*Reporter).ConsumeResource(0xc002eb5290, {0xc003ff14b8?, 0xc003fa163c?})
	github.com/DataDog/opentelemetry-mapping-go/pkg/[email protected]/reporter.go:137 +0x125
github.com/open-telemetry/opentelemetry-collector-contrib/exporter/datadogexporter.consumeResource(0xc003b1d870?, {0xc003ff14b8, 0xc003fa163c}, 0x407985?)
	github.com/open-telemetry/opentelemetry-collector-contrib/exporter/[email protected]/factory.go:73 +0x37
github.com/open-telemetry/opentelemetry-collector-contrib/exporter/datadogexporter.(*metricsExporter).PushMetricsData(0xc002e8d560, {0x9216420, 0xc0022a32c0}, {0xc003fb3a10?, 0xc003fa163c?})
	github.com/open-telemetry/opentelemetry-collector-contrib/exporter/[email protected]/metrics_exporter.go:203 +0x12d3
github.com/open-telemetry/opentelemetry-collector-contrib/exporter/datadogexporter.(*metricsExporter).PushMetricsDataScrubbed(0xc002e8d560, {0x9216420?, 0xc0022a32c0?}, {0xc003fb3a10?, 0xc003fa163c?})
	github.com/open-telemetry/opentelemetry-collector-contrib/exporter/[email protected]/metrics_exporter.go:185 +0x2c
go.opentelemetry.io/collector/exporter/exporterhelper.(*metricsRequest).Export(0x0?, {0x9216420?, 0xc0022a32c0?})
	go.opentelemetry.io/collector/[email protected]/exporterhelper/metrics.go:59 +0x31
go.opentelemetry.io/collector/exporter/exporterhelper.(*timeoutSender).send(0xc00274ec78?, {0x9216420?, 0xc0022a32c0?}, {0x91cd7f0?, 0xc002e7cca8?})
	go.opentelemetry.io/collector/[email protected]/exporterhelper/timeout_sender.go:43 +0x48
go.opentelemetry.io/collector/exporter/exporterhelper.(*baseRequestSender).send(0xc002e86380?, {0x9216420?, 0xc0022a32c0?}, {0x91cd7f0?, 0xc002e7cca8?})
	go.opentelemetry.io/collector/[email protected]/exporterhelper/common.go:35 +0x30
go.opentelemetry.io/collector/exporter/exporterhelper.(*metricsSenderWithObservability).send(0xc002eb5da0, {0x92168d0?, 0xc001d7df50?}, {0x91cd7f0?, 0xc002e7cca8?})
	go.opentelemetry.io/collector/[email protected]/exporterhelper/metrics.go:155 +0x7e
go.opentelemetry.io/collector/exporter/exporterhelper.newQueueSender.func1({0x92168d0?, 0xc001d7df50?}, {0x91cd7f0?, 0xc002e7cca8?})
	go.opentelemetry.io/collector/[email protected]/exporterhelper/queue_sender.go:95 +0x84
go.opentelemetry.io/collector/exporter/internal/queue.(*boundedMemoryQueue[...]).Consume(0x9221bc0, 0xc002eb5e00)
	go.opentelemetry.io/collector/[email protected]/internal/queue/bounded_memory_queue.go:57 +0xc7
go.opentelemetry.io/collector/exporter/internal/queue.(*Consumers[...]).Start.func1()
	go.opentelemetry.io/collector/[email protected]/internal/queue/consumers.go:43 +0x79
created by go.opentelemetry.io/collector/exporter/internal/queue.(*Consumers[...]).Start in goroutine 1
	go.opentelemetry.io/collector/[email protected]/internal/queue/consumers.go:39 +0x7d
panic: assignment to entry in nil map

goroutine 124 [running]:
github.com/DataDog/opentelemetry-mapping-go/pkg/inframetadata/internal/hostmap.(*HostMap).Update(0xc002e96e20, {0xc00252c570, 0x24}, {0xc003fb59f8?, 0xc002253790?})
	github.com/DataDog/opentelemetry-mapping-go/pkg/[email protected]/internal/hostmap/hostmap.go:243 +0x619
github.com/DataDog/opentelemetry-mapping-go/pkg/inframetadata.(*Reporter).ConsumeResource(0xc002eb5290, {0xc003fb59f8?, 0xc002253790?})
	github.com/DataDog/opentelemetry-mapping-go/pkg/[email protected]/reporter.go:137 +0x125
github.com/open-telemetry/opentelemetry-collector-contrib/exporter/datadogexporter.consumeResource(0xc0034677f8?, {0xc003fb59f8, 0xc002253790}, 0xc0034679b8?)
	github.com/open-telemetry/opentelemetry-collector-contrib/exporter/[email protected]/factory.go:73 +0x37
github.com/open-telemetry/opentelemetry-collector-contrib/exporter/datadogexporter.(*metricsExporter).PushMetricsData(0xc002e8d560, {0x9216420, 0xc002cf2f60}, {0xc002e7cb70?, 0xc002253790?})
	github.com/open-telemetry/opentelemetry-collector-contrib/exporter/[email protected]/metrics_exporter.go:203 +0x12d3
github.com/open-telemetry/opentelemetry-collector-contrib/exporter/datadogexporter.(*metricsExporter).PushMetricsDataScrubbed(0xc002e8d560, {0x9216420?, 0xc002cf2f60?}, {0xc002e7cb70?, 0xc002253790?})
	github.com/open-telemetry/opentelemetry-collector-contrib/exporter/[email protected]/metrics_exporter.go:185 +0x2c
go.opentelemetry.io/collector/exporter/exporterhelper.(*metricsRequest).Export(0x0?, {0x9216420?, 0xc002cf2f60?})
	go.opentelemetry.io/collector/[email protected]/exporterhelper/metrics.go:59 +0x31
go.opentelemetry.io/collector/exporter/exporterhelper.(*timeoutSender).send(0xc002a76390?, {0x9216420?, 0xc002cf2f60?}, {0x91cd7f0?, 0xc002e7cc00?})
	go.opentelemetry.io/collector/[email protected]/exporterhelper/timeout_sender.go:43 +0x48
go.opentelemetry.io/collector/exporter/exporterhelper.(*baseRequestSender).send(0xc002e86380?, {0x9216420?, 0xc002cf2f60?}, {0x91cd7f0?, 0xc002e7cc00?})
	go.opentelemetry.io/collector/[email protected]/exporterhelper/common.go:35 +0x30
go.opentelemetry.io/collector/exporter/exporterhelper.(*metricsSenderWithObservability).send(0xc002eb5da0, {0x92168d0?, 0xc001d7dd00?}, {0x91cd7f0?, 0xc002e7cc00?})
	go.opentelemetry.io/collector/[email protected]/exporterhelper/metrics.go:155 +0x7e
go.opentelemetry.io/collector/exporter/exporterhelper.newQueueSender.func1({0x92168d0?, 0xc001d7dd00?}, {0x91cd7f0?, 0xc002e7cc00?})
	go.opentelemetry.io/collector/[email protected]/exporterhelper/queue_sender.go:95 +0x84
go.opentelemetry.io/collector/exporter/internal/queue.(*boundedMemoryQueue[...]).Consume(0x9221bc0, 0xc002eb5e00)
	go.opentelemetry.io/collector/[email protected]/internal/queue/bounded_memory_queue.go:57 +0xc7
go.opentelemetry.io/collector/exporter/internal/queue.(*Consumers[...]).Start.func1()
	go.opentelemetry.io/collector/[email protected]/internal/queue/consumers.go:43 +0x79
created by go.opentelemetry.io/collector/exporter/internal/queue.(*Consumers[...]).Start in goroutine 1
	go.opentelemetry.io/collector/[email protected]/internal/queue/consumers.go:39 +0x7d

Investigation: It looks like this is originating from the ConsumeResource call on the Reporter struct. This struct appear to have an uninitialized hostmap

[mx-psi]

@atmask Apologies for the delay in replying here, we don't monitor the issues on this repository very frequently. Would you mind filing a support ticket with Datadog (see https://www.datadoghq.com/support/)? You can mention this issue and ping me directly