# Semantic conventions

This document describes
which [OpenTelemetry Semantic Conventions](https://github.com/open-telemetry/opentelemetry-specification/tree/main/specification/trace/semantic_conventions)
are implemented by Java autoinstrumentation and which ones are not.

## Http Server

| Attribute                                   | Required | Implemented? |
|---------------------------------------------|:--------:|:------------:|
| `http.method`                               |    Y     |      +       |
| `http.url`                                  |    N     |    - [1]     |
| `http.target`                               |    N     |    + [1]     |
| `http.host`                                 |    N     |    + [1]     |
| `http.scheme`                               |    N     |    + [1]     |
| `http.status_code`                          |    Y     |      +       |
| `http.flavor`                               |    N     |    + [2]     |
| `http.user_agent`                           |    N     |      +       |
| `http.request_content_length`               |    N     |      -       |
| `http.request_content_length_uncompressed`  |    N     |      -       |
| `http.response_content_length`              |    N     |      -       |
| `http.response_content_length_uncompressed` |    N     |      -       |
| `http.server_name`                          |    N     |      -       |
| `http.route`                                |    N     |      -       |
| `http.client_ip`                            |    N     |      +       |

**[1]:** Server instrumentations capture `http.scheme`, `http.host`, and `http.target` and do not
capture `http.url`.

**[2]:** In case of Armeria, return values
are [SessionProtocol](https://github.com/line/armeria/blob/master/core/src/main/java/com/linecorp/armeria/common/SessionProtocol.java),
not values defined by spec.

## Http Client

| Attribute                                   | Required | Implemented? |
|---------------------------------------------|:--------:|:------------:|
| `http.method`                               |    Y     |      +       |
| `http.url`                                  |    N     |      +       |
| `http.target`                               |    N     |    - [1]     |
| `http.host`                                 |    N     |    - [1]     |
| `http.scheme`                               |    N     |    - [1]     |
| `http.status_code`                          |    Y     |      +       |
| `http.flavor`                               |    N     |    + [2]     |
| `http.user_agent`                           |    N     |      +       |
| `http.request_content_length`               |    N     |      -       |
| `http.request_content_length_uncompressed`  |    N     |      -       |
| `http.response_content_length`              |    N     |      -       |
| `http.response_content_length_uncompressed` |    N     |      -       |

**[1]:** Client instrumentations capture `http.url` and do not capture `http.scheme`, `http.host`
and `http.target`.

**[2]:** In case of Armeria, return values
are [SessionProtocol](https://github.com/line/armeria/blob/master/core/src/main/java/com/linecorp/armeria/common/SessionProtocol.java),
not values defined by spec.

## RPC

| Attribute     | Required | Implemented? |
|---------------|:--------:|:------------:|
| `rpc.system`  |    Y     |      +       |
| `rpc.service` |    N     |      +       |
| `rpc.method`  |    N     |      +       |

## Database

| Attribute                  | Required |                         Implemented?                          |
|----------------------------|:--------:|:-------------------------------------------------------------:|
| `db.system`                |    Y     |                               +                               |
| `db.connection_string`     |    N     |             only set for Redis, JDBC and MongoDB              |
| `db.user`                  |    N     |                       only set for JDBC                       |
| `db.jdbc.driver_classname` |    N     |                               -                               |
| `db.mssql.instance_name`   |    N     |                               -                               |
| `db.name`                  |    N     |          only set of JDBC, Mongo, Geode and MongoDB           |
| `db.statement`             |    N     | +, except for ElasticSearch and Memcached, see `db.operation` |
| `db.operation`             |    N     |        only set for ElasticSearch, Memcached and JDBC         |
| `db.cassandra.keyspace`    |    Y     |                               +                               |
| `db.hbase`                 |    Y     |                   -, HBase is not supported                   |
| `db.redis.database_index`  |    N     |          only set for Lettuce driver, not for Jedis           |
| `db.mongodb.collection`    |    Y     |                               -                               |

## Messaging

| Attribute name                                    |     Required?      |          Implemented?           |
|---------------------------------------------------|:------------------:|:-------------------------------:|
| `messaging.system`                                |         Y          |                +                |
| `messaging.destination.name`                      |         Y          |                +                |
| `messaging.destination.kind`                      |         Y          |                +                |
| `messaging.destination.temporary`                 |         N          |                -                |
| `net.app.protocol.name`                           |         N          |                -                |
| `net.app.protocol.version`                        |         N          |                -                |
| `messaging.message.id`                            |         N          |          only for JMS           |
| `messaging.message.conversation_id`               |         N          |          only for JMS           |
| `messaging.message.payload_size_bytes`            |         N          | only for RabbitMQ and Kafka [1] |
| `messaging.message.payload_compressed_size_bytes` |         N          |                -                |
| `messaging.operation`                             | for consumers only |                +                |

**[1]:** Kafka consumer instrumentation sets this to the serialized size of the value