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# TsFile-CLI

`tsfile-cli` is a single, pipe-friendly C++ command-line tool for inspecting
**and** importing Apache TsFile (`.tsfile`) files from the shell. Read commands print data to **stdout** and
diagnostics to **stderr**, so they compose with `awk`, `jq`, `sort`, and friends;
the `write` command imports CSV/TSV into a new `.tsfile`.

## Building from source

The CLI is part of the C++ module. Build it with the Maven wrapper, which
downloads a pinned CMake and compiles the whole C++ module (the `libtsfile`
shared library + the `tsfile-cli` executable) for you.

**Prerequisites:** a JDK (8+) to run Maven, and a C++11 compiler (GCC / Clang).

From the repository root:

```bash
./mvnw clean package -P with-cpp
```

This produces, under `cpp/target/build/`:

| Artifact | Path |
|---|---|
| CLI executable | `cpp/target/build/bin/tsfile-cli` |
| Shared library | `cpp/target/build/lib/libtsfile.so` (Linux) — `libtsfile.dylib` on macOS |

To build just the CLI without Maven (needs a C++11 compiler and CMake ≥ 3.11), run
from `cpp/` instead:

```bash
mkdir -p build/Release && cd build/Release
cmake ../.. -DCMAKE_BUILD_TYPE=Release
make -j tsfile_cli      # -> cpp/build/Release/bin/tsfile-cli
```

`libtsfile` is built alongside under `cpp/build/Release/lib/`.

`tsfile-cli` is dynamically linked against `libtsfile`. Run it **in place** by its
full path and it finds the library automatically:

```bash
cpp/target/build/bin/tsfile-cli --version    # -> tsfile-cli (Apache TsFile C++) <version>
cpp/target/build/bin/tsfile-cli --help
```

To run the binary from **somewhere else** (e.g. after copying it out of the build
tree), the dynamic loader must be able to find `libtsfile.so`. Either point the
loader at the build's `lib/` directory, or copy the library to a standard
location:

```bash
# point the loader at the build's lib directory (Linux; macOS uses DYLD_LIBRARY_PATH)
export LD_LIBRARY_PATH=/path/to/cpp/target/build/lib:$LD_LIBRARY_PATH

# — or — copy the library to a system library path
sudo cp cpp/target/build/lib/libtsfile.so /usr/local/lib/ && sudo ldconfig
```

## Usage

```text
tsfile-cli <command> [options] <file.tsfile>
tsfile-cli --help | --version | help
```

Exit codes: `0` success, `1` usage/argument error, `2` file open/corrupt,
`3` query/runtime error.

### Reading

| Command | Description |
|---|---|
| `ls` | List devices (tree model) or tables (table model), one name per line |
| `schema` | Per-series `target, measurement, datatype, encoding, compression` |
| `meta` | File summary: model, device/table/series counts, time range, file size |
| `stats` | Per-series `count, start_time, end_time, min, max, first, last, sum` |
| `count` | Per-series row counts plus a `total` row (from statistics, no page scan) |
| `head` | First N rows (default 10; use `-n`) |
| `cat` | All matching rows, streamed (`table` format buffers to align columns) |
| `sample` | Reproducible reservoir sample (default 10; `-n`, `--seed`) |

The metadata commands (`ls` / `schema` / `meta` / `stats` / `count`) answer most
questions **without decoding data pages**.

Shared options:

| Option | Meaning |
|---|---|
| `-f, --format csv\|tsv\|json\|table` | Output format; defaults to `table` on a TTY, `tsv` when piped |
| `-d, --device <id>` / `-t, --table <name>` | Scope to one device / table (mutually exclusive) |
| `-m, --measurements a,b,c` | Column projection (`schema`, `stats`, `count`, `head`, `cat`, `sample`) |
| `-n, --limit N` / `--offset N` | Max rows / rows to skip (`head`, `cat`; `--offset` not valid for `sample`) |
| `--start <ms>` / `--end <ms>` | Inclusive epoch-millisecond time range (`head`, `cat`, `sample`) |
| `--seed N` | Reproducible sampling seed (`sample` only) |
| `--tag-filter C OP V` / `--tag-between C L U` / `--tag-not-between C L U` | Table TAG predicate for `head`, `cat`, `sample`; `OP` is `eq`, `neq`, `lt`, `lteq`, `gt`, `gteq`, `regexp`, or `not-regexp` |
| `--no-header` | Omit the header row |
| `--model tree\|table` | Force the model (otherwise auto-detected) |

`json` output is NDJSON (one JSON object per line, one row per object; numbers/booleans bare, other values
quoted, nulls as `null`; non-finite floats — NaN/Inf — become `null`). CSV output
follows RFC 4180. Timestamps are raw epoch milliseconds. The `table` format
buffers all rows in memory to align columns, so prefer `csv`/`tsv`/`json` when
dumping large files.

```bash
BIN=cpp/build/Debug/bin/tsfile-cli
$BIN ls -f tsv data.tsfile                          # list tables / devices
$BIN meta data.tsfile                               # quick file overview
$BIN count -t table1 -f tsv data.tsfile             # row counts, no page scan
$BIN cat -t table1 --tag-filter device eq dev_1 -m temp -f tsv data.tsfile
$BIN cat -m temp,humidity --start 1700000000000 -f csv data.tsfile | head
$BIN sample -m temp -n 20 --seed 42 -f json data.tsfile | jq .
```

> For a table-model file, the row commands (`head` / `cat` / `sample`) query the
> **first** table unless you pass `-t <table>`. `count` covers all tables.

### Writing (import)

`tsfile-cli write` imports CSV/TSV rows into a **new table-model** `.tsfile` (the
output is overwritten). The first input column is the timestamp (epoch
milliseconds); the remaining columns are declared explicitly with `--columns` —
there is no type inference.

Timestamps must be **strictly increasing per device**, where a device is
identified by its `tag` column values (rows that share the same tags form one
device's timeline). Rows for different tag combinations may freely interleave and
reuse timestamps. Out-of-order input is rejected with the offending line number,
and a failed import leaves no output file behind. `--output` must differ from the
input file.

```text
tsfile-cli write --table <name> --columns <spec> -o <out.tsfile> \
                 [-f csv|tsv] [--no-header] [--header-match] [-v] [<input> | -]
```

`--columns` is a comma-separated list of `name:TYPE:category`, where `category`
(case-insensitive) is `tag` or `field` and `TYPE` (case-insensitive) is one of
`BOOLEAN, INT32, INT64, FLOAT, DOUBLE, STRING, TEXT, TIMESTAMP, DATE, BLOB` — for
example `--columns "id1:STRING:tag,s1:INT64:field"`. `DATE` cells are written as
`YYYY-MM-DD`; `TIMESTAMP` cells as epoch milliseconds. Each column is stored with
the engine's default encoding and compression for its type.

| Option | Meaning |
|---|---|
| `--table <name>` | Output table name (lower-cased) |
| `--columns <spec>` | Ordered data columns (excludes the leading timestamp column) |
| `-o, --output <path>` | Output `.tsfile` (required; overwritten) |
| `<input>` / `-` | Input file, or `-` / omitted for stdin |
| `-f csv\|tsv` | Input delimiter (default csv; `json` / `table` are rejected) |
| `--no-header` | Input has no header row (default: first line is a header and is skipped) |
| `--header-match` | Validate header names against `--columns` |
| `-v, --verbose` | Print `wrote N rows to <out>` to stderr (otherwise silent on success) |

An empty cell is written as null. The command is silent on success (Unix-style);
pass `-v` for a one-line summary.

```bash
# round-trip through a pipe
printf 'time,id1,s1\n0,dev,0\n1,dev,10\n' \
  | tsfile-cli write --table t1 --columns "id1:STRING:tag,s1:INT64:field" -o out.tsfile -
tsfile-cli count -f tsv out.tsfile          # -> t1.dev  s1  2
```

## Using the skill with an AI assistant

`cpp/tools/skills/tsfile-cli/SKILL.md` is a machine-readable reference that
documents how to drive `tsfile-cli`. AI coding assistants that support skills can
load it to help you inspect and import `.tsfile` files.