# srv/

## Overview

The `srv/` directory contains the 7 ROS service definitions exposed by the Cartographer ROS package. They form the control and query interface to a running Cartographer node.

## Services

- `FinishTrajectory.srv` — finishes a running trajectory.
- `GetTrajectoryStates.srv` — retrieves the state of all trajectories.
- `ReadMetrics.srv` — reads the current metric families.
- `StartTrajectory.srv` — starts a new trajectory with a given configuration.
- `SubmapQuery.srv` — queries the textures of a submap.
- `TrajectoryQuery.srv` — retrieves the poses of a trajectory.
- `WriteState.srv` — serializes the full Cartographer state to a file.

## Common Response Convention

Most services return a `cartographer_ros_msgs/StatusResponse` with a `code` from `StatusCode.msg` and a human-readable `message`. Callers should check that `code == StatusCode.OK` before using the remaining response fields.

```{toctree}
:maxdepth: 2
:caption: srv/

FinishTrajectory
GetTrajectoryStates
ReadMetrics
StartTrajectory
SubmapQuery
TrajectoryQuery
WriteState
```