Add ability to parse Schema files according to OTEP 0152

The parser and parsed representation (AST) are placed in a separate
Go module so that they are can be consumed independently without
the need to bring the rest of the SDK.

Ability to use the parsed representation for schema conversions
can be added later.

.github/dependabot.yml

@@ -336,3 +336,14 @@ updates:
     schedule:
       day: sunday
       interval: weekly
+
+  -
+    package-ecosystem: gomod
+    directory: /schema
+    labels:
+      - dependencies
+      - go
+      - "Skip Changelog"
+    schedule:
+      day: sunday
+      interval: weekly

CHANGELOG.md

@@ -20,6 +20,7 @@ This release includes an API and SDK for the tracing signal that will comply wit
 ### Added
 
 - OTLP trace exporter now sets the `SchemaURL` field in the exported telemetry if the Tracer has `WithSchemaURL` option. (#2242)
+- Added a new `schema` module to help parse Schema Files in OTEP 0152 format. (#2267)
 
 ### Fixed
 

bridge/opencensus/go.mod

@@ -73,3 +73,5 @@ replace go.opentelemetry.io/otel/exporters/otlp/otlpmetric/otlpmetrichttp => ../
 replace go.opentelemetry.io/otel/bridge/opencensus/test => ./test
 
 replace go.opentelemetry.io/otel/example/fib => ../../example/fib
+
+replace go.opentelemetry.io/otel/schema => ../../schema

bridge/opencensus/test/go.mod

@@ -69,3 +69,5 @@ replace go.opentelemetry.io/otel/sdk/metric => ../../../sdk/metric
 replace go.opentelemetry.io/otel/trace => ../../../trace
 
 replace go.opentelemetry.io/otel/example/fib => ../../../example/fib
+
+replace go.opentelemetry.io/otel/schema => ../../../schema

bridge/opentracing/go.mod

@@ -69,3 +69,5 @@ replace go.opentelemetry.io/otel/exporters/otlp/otlpmetric/otlpmetrichttp => ../
 replace go.opentelemetry.io/otel/bridge/opencensus/test => ../opencensus/test
 
 replace go.opentelemetry.io/otel/example/fib => ../../example/fib
+
+replace go.opentelemetry.io/otel/schema => ../../schema

example/fib/go.mod

@@ -68,3 +68,5 @@ replace go.opentelemetry.io/otel/sdk/metric => ../../sdk/metric
 replace go.opentelemetry.io/otel/trace => ../../trace
 
 replace go.opentelemetry.io/otel/example/fib => ./
+
+replace go.opentelemetry.io/otel/schema => ../../schema

example/jaeger/go.mod

@@ -69,3 +69,5 @@ replace go.opentelemetry.io/otel/exporters/otlp/otlpmetric/otlpmetrichttp => ../
 replace go.opentelemetry.io/otel/bridge/opencensus/test => ../../bridge/opencensus/test
 
 replace go.opentelemetry.io/otel/example/fib => ../fib
+
+replace go.opentelemetry.io/otel/schema => ../../schema

example/namedtracer/go.mod

@@ -71,3 +71,5 @@ replace go.opentelemetry.io/otel/exporters/otlp/otlpmetric/otlpmetrichttp => ../
 replace go.opentelemetry.io/otel/bridge/opencensus/test => ../../bridge/opencensus/test
 
 replace go.opentelemetry.io/otel/example/fib => ../fib
+
+replace go.opentelemetry.io/otel/schema => ../../schema

example/opencensus/go.mod

@@ -73,3 +73,5 @@ replace go.opentelemetry.io/otel/exporters/otlp/otlpmetric/otlpmetrichttp => ../
 replace go.opentelemetry.io/otel/bridge/opencensus/test => ../../bridge/opencensus/test
 
 replace go.opentelemetry.io/otel/example/fib => ../fib
+
+replace go.opentelemetry.io/otel/schema => ../../schema

example/otel-collector/go.mod

@@ -72,3 +72,5 @@ replace go.opentelemetry.io/otel/exporters/otlp/otlpmetric/otlpmetrichttp => ../
 replace go.opentelemetry.io/otel/bridge/opencensus/test => ../../bridge/opencensus/test
 
 replace go.opentelemetry.io/otel/example/fib => ../fib
+
+replace go.opentelemetry.io/otel/schema => ../../schema

example/passthrough/go.mod

@@ -72,3 +72,5 @@ replace go.opentelemetry.io/otel/exporters/otlp/otlpmetric/otlpmetrichttp => ../
 replace go.opentelemetry.io/otel/bridge/opencensus/test => ../../bridge/opencensus/test
 
 replace go.opentelemetry.io/otel/example/fib => ../fib
+
+replace go.opentelemetry.io/otel/schema => ../../schema

example/prometheus/go.mod

@@ -71,3 +71,5 @@ replace go.opentelemetry.io/otel/exporters/otlp/otlpmetric/otlpmetrichttp => ../
 replace go.opentelemetry.io/otel/bridge/opencensus/test => ../../bridge/opencensus/test
 
 replace go.opentelemetry.io/otel/example/fib => ../fib
+
+replace go.opentelemetry.io/otel/schema => ../../schema

example/zipkin/go.mod

@@ -70,3 +70,5 @@ replace go.opentelemetry.io/otel/exporters/otlp/otlpmetric/otlpmetrichttp => ../
 replace go.opentelemetry.io/otel/bridge/opencensus/test => ../../bridge/opencensus/test
 
 replace go.opentelemetry.io/otel/example/fib => ../fib
+
+replace go.opentelemetry.io/otel/schema => ../../schema

exporters/jaeger/go.mod

@@ -73,3 +73,5 @@ replace go.opentelemetry.io/otel/exporters/otlp/otlpmetric/otlpmetrichttp => ../
 replace go.opentelemetry.io/otel/bridge/opencensus/test => ../../bridge/opencensus/test
 
 replace go.opentelemetry.io/otel/example/fib => ../../example/fib
+
+replace go.opentelemetry.io/otel/schema => ../../schema

exporters/otlp/otlpmetric/go.mod

@@ -80,3 +80,5 @@ replace go.opentelemetry.io/otel/exporters/otlp/otlpmetric/otlpmetrichttp => ./o
 replace go.opentelemetry.io/otel/bridge/opencensus/test => ../../../bridge/opencensus/test
 
 replace go.opentelemetry.io/otel/example/fib => ../../../example/fib
+
+replace go.opentelemetry.io/otel/schema => ../../../schema

exporters/otlp/otlpmetric/otlpmetricgrpc/go.mod

@@ -78,3 +78,5 @@ replace go.opentelemetry.io/otel/exporters/otlp/otlpmetric/otlpmetrichttp => ../
 replace go.opentelemetry.io/otel/bridge/opencensus/test => ../../../../bridge/opencensus/test
 
 replace go.opentelemetry.io/otel/example/fib => ../../../../example/fib
+
+replace go.opentelemetry.io/otel/schema => ../../../../schema

exporters/otlp/otlpmetric/otlpmetrichttp/go.mod

@@ -80,3 +80,5 @@ replace go.opentelemetry.io/otel/exporters/otlp/otlpmetric/otlpmetricgrpc => ../
 replace go.opentelemetry.io/otel/bridge/opencensus/test => ../../../../bridge/opencensus/test
 
 replace go.opentelemetry.io/otel/example/fib => ../../../../example/fib
+
+replace go.opentelemetry.io/otel/schema => ../../../../schema

exporters/otlp/otlptrace/go.mod

@@ -76,3 +76,5 @@ replace go.opentelemetry.io/otel/exporters/otlp/otlpmetric/otlpmetrichttp => ../
 replace go.opentelemetry.io/otel/bridge/opencensus/test => ../../../bridge/opencensus/test
 
 replace go.opentelemetry.io/otel/example/fib => ../../../example/fib
+
+replace go.opentelemetry.io/otel/schema => ../../../schema

exporters/otlp/otlptrace/otlptracegrpc/go.mod

@@ -72,3 +72,5 @@ replace go.opentelemetry.io/otel/exporters/otlp/otlpmetric/otlpmetrichttp => ../
 replace go.opentelemetry.io/otel/bridge/opencensus/test => ../../../../bridge/opencensus/test
 
 replace go.opentelemetry.io/otel/example/fib => ../../../../example/fib
+
+replace go.opentelemetry.io/otel/schema => ../../../../schema

exporters/otlp/otlptrace/otlptracehttp/go.mod

@@ -73,3 +73,5 @@ replace go.opentelemetry.io/otel/exporters/otlp/otlpmetric/otlpmetrichttp => ../
 replace go.opentelemetry.io/otel/bridge/opencensus/test => ../../../../bridge/opencensus/test
 
 replace go.opentelemetry.io/otel/example/fib => ../../../../example/fib
+
+replace go.opentelemetry.io/otel/schema => ../../../../schema

exporters/prometheus/go.mod

@@ -75,3 +75,5 @@ replace go.opentelemetry.io/otel/exporters/otlp/otlpmetric/otlpmetrichttp => ../
 replace go.opentelemetry.io/otel/bridge/opencensus/test => ../../bridge/opencensus/test
 
 replace go.opentelemetry.io/otel/example/fib => ../../example/fib
+
+replace go.opentelemetry.io/otel/schema => ../../schema

exporters/stdout/stdoutmetric/go.mod

@@ -73,3 +73,5 @@ replace go.opentelemetry.io/otel/exporters/otlp/otlpmetric/otlpmetrichttp => ../
 replace go.opentelemetry.io/otel/bridge/opencensus/test => ../../../bridge/opencensus/test
 
 replace go.opentelemetry.io/otel/example/fib => ../../../example/fib
+
+replace go.opentelemetry.io/otel/schema => ../../../schema

exporters/stdout/stdouttrace/go.mod

@@ -71,3 +71,5 @@ replace go.opentelemetry.io/otel/exporters/otlp/otlpmetric/otlpmetrichttp => ../
 replace go.opentelemetry.io/otel/bridge/opencensus/test => ../../../bridge/opencensus/test
 
 replace go.opentelemetry.io/otel/example/fib => ../../../example/fib
+
+replace go.opentelemetry.io/otel/schema => ../../../schema

exporters/zipkin/go.mod

@@ -74,3 +74,5 @@ replace go.opentelemetry.io/otel/exporters/otlp/otlpmetric/otlpmetrichttp => ../
 replace go.opentelemetry.io/otel/bridge/opencensus/test => ../../bridge/opencensus/test
 
 replace go.opentelemetry.io/otel/example/fib => ../../example/fib
+
+replace go.opentelemetry.io/otel/schema => ../../schema

go.mod

@@ -69,3 +69,5 @@ replace go.opentelemetry.io/otel/exporters/otlp/otlpmetric/otlpmetrichttp => ./e
 replace go.opentelemetry.io/otel/bridge/opencensus/test => ./bridge/opencensus/test
 
 replace go.opentelemetry.io/otel/example/fib => ./example/fib
+
+replace go.opentelemetry.io/otel/schema => ./schema

internal/metric/go.mod

@@ -69,3 +69,5 @@ replace go.opentelemetry.io/otel/exporters/otlp/otlpmetric/otlpmetrichttp => ../
 replace go.opentelemetry.io/otel/bridge/opencensus/test => ../../bridge/opencensus/test
 
 replace go.opentelemetry.io/otel/example/fib => ../../example/fib
+
+replace go.opentelemetry.io/otel/schema => ../../schema

internal/tools/go.mod

@@ -75,3 +75,5 @@ replace go.opentelemetry.io/otel/exporters/otlp/otlpmetric/otlpmetrichttp => ../
 replace go.opentelemetry.io/otel/bridge/opencensus/test => ../../bridge/opencensus/test
 
 replace go.opentelemetry.io/otel/example/fib => ../../example/fib
+
+replace go.opentelemetry.io/otel/schema => ../../schema

metric/go.mod

@@ -70,3 +70,5 @@ replace go.opentelemetry.io/otel/exporters/otlp/otlpmetric/otlpmetrichttp => ../
 replace go.opentelemetry.io/otel/bridge/opencensus/test => ../bridge/opencensus/test
 
 replace go.opentelemetry.io/otel/example/fib => ../example/fib
+
+replace go.opentelemetry.io/otel/schema => ../schema

schema/go.mod

@@ -0,0 +1,71 @@
+module go.opentelemetry.io/otel/schema
+
+go 1.15
+
+require (
+	github.com/Masterminds/semver/v3 v3.1.1
+	github.com/stretchr/testify v1.7.0
+	gopkg.in/yaml.v2 v2.4.0
+)
+
+replace go.opentelemetry.io/otel => ../
+
+replace go.opentelemetry.io/otel/bridge/opencensus => ../bridge/opencensus
+
+replace go.opentelemetry.io/otel/bridge/opencensus/test => ../bridge/opencensus/test
+
+replace go.opentelemetry.io/otel/bridge/opentracing => ../bridge/opentracing
+
+replace go.opentelemetry.io/otel/example/fib => ../example/fib
+
+replace go.opentelemetry.io/otel/example/jaeger => ../example/jaeger
+
+replace go.opentelemetry.io/otel/example/namedtracer => ../example/namedtracer
+
+replace go.opentelemetry.io/otel/example/opencensus => ../example/opencensus
+
+replace go.opentelemetry.io/otel/example/otel-collector => ../example/otel-collector
+
+replace go.opentelemetry.io/otel/example/passthrough => ../example/passthrough
+
+replace go.opentelemetry.io/otel/example/prometheus => ../example/prometheus
+
+replace go.opentelemetry.io/otel/example/zipkin => ../example/zipkin
+
+replace go.opentelemetry.io/otel/exporters/jaeger => ../exporters/jaeger
+
+replace go.opentelemetry.io/otel/exporters/otlp/otlpmetric => ../exporters/otlp/otlpmetric
+
+replace go.opentelemetry.io/otel/exporters/otlp/otlpmetric/otlpmetricgrpc => ../exporters/otlp/otlpmetric/otlpmetricgrpc
+
+replace go.opentelemetry.io/otel/exporters/otlp/otlpmetric/otlpmetrichttp => ../exporters/otlp/otlpmetric/otlpmetrichttp
+
+replace go.opentelemetry.io/otel/exporters/otlp/otlptrace => ../exporters/otlp/otlptrace
+
+replace go.opentelemetry.io/otel/exporters/otlp/otlptrace/otlptracegrpc => ../exporters/otlp/otlptrace/otlptracegrpc
+
+replace go.opentelemetry.io/otel/exporters/otlp/otlptrace/otlptracehttp => ../exporters/otlp/otlptrace/otlptracehttp
+
+replace go.opentelemetry.io/otel/exporters/prometheus => ../exporters/prometheus
+
+replace go.opentelemetry.io/otel/exporters/stdout/stdoutmetric => ../exporters/stdout/stdoutmetric
+
+replace go.opentelemetry.io/otel/exporters/stdout/stdouttrace => ../exporters/stdout/stdouttrace
+
+replace go.opentelemetry.io/otel/exporters/zipkin => ../exporters/zipkin
+
+replace go.opentelemetry.io/otel/internal/metric => ../internal/metric
+
+replace go.opentelemetry.io/otel/internal/tools => ../internal/tools
+
+replace go.opentelemetry.io/otel/metric => ../metric
+
+replace go.opentelemetry.io/otel/schema => ./
+
+replace go.opentelemetry.io/otel/sdk => ../sdk
+
+replace go.opentelemetry.io/otel/sdk/export/metric => ../sdk/export/metric
+
+replace go.opentelemetry.io/otel/sdk/metric => ../sdk/metric
+
+replace go.opentelemetry.io/otel/trace => ../trace

schema/go.sum

@@ -0,0 +1,15 @@
+github.com/Masterminds/semver/v3 v3.1.1 h1:hLg3sBzpNErnxhQtUy/mmLR2I9foDujNK030IGemrRc=
+github.com/Masterminds/semver/v3 v3.1.1/go.mod h1:VPu/7SZ7ePZ3QOrcuXROw5FAcLl4a0cBrbBpGY/8hQs=
+github.com/davecgh/go-spew v1.1.0 h1:ZDRjVQ15GmhC3fiQ8ni8+OwkZQO4DARzQgrnXU1Liz8=
+github.com/davecgh/go-spew v1.1.0/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
+github.com/pmezard/go-difflib v1.0.0 h1:4DBwDE0NGyQoBHbLQYPwSUPoCMWR5BEzIk/f1lZbAQM=
+github.com/pmezard/go-difflib v1.0.0/go.mod h1:iKH77koFhYxTK1pcRnkKkqfTogsbg7gZNVY4sRDYZ/4=
+github.com/stretchr/objx v0.1.0/go.mod h1:HFkY916IF+rwdDfMAkV7OtwuqBVzrE8GR6GFx+wExME=
+github.com/stretchr/testify v1.7.0 h1:nwc3DEeHmmLAfoZucVR881uASk0Mfjw8xYJ99tb5CcY=
+github.com/stretchr/testify v1.7.0/go.mod h1:6Fq8oRcR53rry900zMqJjRRixrwX3KX962/h/Wwjteg=
+gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405 h1:yhCVgyC4o1eVCa2tZl7eS0r+SDo693bJlVdllGtEeKM=
+gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=
+gopkg.in/yaml.v2 v2.4.0 h1:D8xgwECY7CYvx+Y2n4sBz93Jn9JRvxdiyyo8CTfuKaY=
+gopkg.in/yaml.v2 v2.4.0/go.mod h1:RDklbk79AGWmwhnvt/jBztapEOGDOx6ZbXqjP6csGnQ=
+gopkg.in/yaml.v3 v3.0.0-20200313102051-9f266ea9e77c h1:dUUwHk2QECo/6vqA44rthZ8ie2QXMNeKRTHCNY2nXvo=
+gopkg.in/yaml.v3 v3.0.0-20200313102051-9f266ea9e77c/go.mod h1:K4uyk7z7BCEPqu6E+C64Yfv1cQ7kz7rIZviUmN+EgEM=

schema/v1.0/ast/ast_schema.go

@@ -0,0 +1,61 @@
+// Copyright The OpenTelemetry Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package ast // import "go.opentelemetry.io/otel/schema/v1.0/ast"
+
+import "go.opentelemetry.io/otel/schema/v1.0/types"
+
+// Schema represents a Schema file in FileFormat 1.0.0 as defined in
+// https://github.com/open-telemetry/oteps/blob/main/text/0152-telemetry-schemas.md
+type Schema struct {
+	// Schema file format. SHOULD be 1.0.0 for the current specification version.
+	// See https://github.com/open-telemetry/oteps/blob/main/text/0152-telemetry-schemas.md#schema-file-format-number
+	FileFormat string `yaml:"file_format"`
+
+	// Schema URL is an identifier of a Schema. The URL specifies a location of this
+	// Schema File that can be retrieved (so it is a URL and not just a URI) using HTTP
+	// or HTTPS protocol.
+	// See https://github.com/open-telemetry/oteps/blob/main/text/0152-telemetry-schemas.md#schema-url
+	SchemaURL string `yaml:"schema_url"`
+
+	// Versions section that lists changes that happened in each particular version.
+	Versions map[types.TelemetryVersion]VersionDef
+}
+
+// VersionDef corresponds to a section representing one version under the "versions"
+// top-level key.
+type VersionDef struct {
+	All        VersionOfAttributes
+	Resources  VersionOfAttributes
+	Spans      VersionOfSpans
+	SpanEvents VersionOfSpanEvents `yaml:"span_events"`
+	Logs       VersionOfLogs
+	Metrics    VersionOfMetrics
+}
+
+// VersionOfAttributes corresponds to a section representing a list of changes that
+// happened in a particular version.
+type VersionOfAttributes struct {
+	Changes []AttributeChanges
+}
+
+// AttributeChanges corresponds to a section representing attribute changes.
+type AttributeChanges struct {
+	RenameAttributes *MappingOfAttributes `yaml:"rename_attributes"`
+}
+
+// MappingOfAttributes corresponds to a section representing a mapping of attribute names.
+// The keys are the old attribute name used the previous version, the values are the
+// new attribute name starting from this version.
+type MappingOfAttributes map[string]string

schema/v1.0/ast/logs.go

@@ -0,0 +1,30 @@
+// Copyright The OpenTelemetry Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package ast // import "go.opentelemetry.io/otel/schema/v1.0/ast"
+
+// VersionOfLogs corresponds to a section representing a list of changes that happened
+// to logs schema in a particular version.
+type VersionOfLogs struct {
+	Changes []LogsChange
+}
+
+// LogsChange corresponds to a section representing logs change.
+type LogsChange struct {
+	RenameAttributes *RenameLogAttributes `yaml:"rename_attributes"`
+}
+
+type RenameLogAttributes struct {
+	AttributeMap map[string]string `yaml:"attribute_map"`
+}

schema/v1.0/ast/metrics.go

@@ -0,0 +1,34 @@
+// Copyright The OpenTelemetry Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package ast // import "go.opentelemetry.io/otel/schema/v1.0/ast"
+
+import "go.opentelemetry.io/otel/schema/v1.0/types"
+
+// VersionOfMetrics corresponds to a section representing a list of changes that happened
+// to metrics schema in a particular version.
+type VersionOfMetrics struct {
+	Changes []MetricsChange
+}
+
+// MetricsChange corresponds to a section representing metrics change.
+type MetricsChange struct {
+	RenameMetrics map[types.MetricName]types.MetricName `yaml:"rename_metrics"`
+	RenameLabels  *LabelMapForMetrics                   `yaml:"rename_labels"`
+}
+
+type LabelMapForMetrics struct {
+	ApplyToMetrics []types.MetricName `yaml:"apply_to_metrics"`
+	LabelMap       map[string]string  `yaml:"label_map"`
+}