cjseq

cjseq is a Rust libray+binary for creating, processing, and modifying CityJSONSeq files, as well as converting to/from CityJSON.

Installation

Installing the binary

1. Install the Rust compiler
2. Run cargo install cjseq
3. Then a binary called cjseq is installed system-wide

Installing the library

1. Install the Rust compiler
2. Run cargo install cjseq

Compiling the project

1. Install the Rust compiler
2. Clone the repository: git clone https://github.com/cityjson/cjseq.git
3. Build the project: cargo build --release
4. Run the program: ./target/release/cjseq --help

Usage

cjseq takes input from either a file or the standard input (stdin, if no file path is given as argument), and it always outputs the results to the standard output (stdout). The output can be a CityJSON object or a CityJSONSeq stream.

Convert CityJSON to CityJSONSeq

The operator "cat" converts a CityJSON file to a CityJSONSeq stream:

cjseq cat myfile.city.json > myfile.city.jsonl

Alternatively, to use stdin as input:

cat myfile.city.json | cjseq cat

Convert CityJSONSeq to CityJSON

The operator "collect" converts a CityJSONSeq stream to a CityJSON file:

cat ./data/3dbag_b2.city.jsonl | cjseq collect > 3dbag_b2.city.json

cjseq collect ./data/3dbag_b2.city.jsonl > 3dbag_b2.city.json

Notice that globbing works for the collect command:

cat ./data/*.city.jsonl | cjseq collect > hugefile.city.json

Filter CityJSONSeq

An input stream of CityJSONSeq can be filtered with the following operators:

--bbox <minx> <miny> <maxx> <maxy>
          Bounding box filter
--cotype <COTYPE>
    Keep only the CityObjects of this type
--exclude
    Excludes the selection, thus remove the selected city object(s)
--radius <x> <y> <radius>
    Circle filter: centre + radius
--random <X>
    1/X chances of a given feature being kept

As an example:

cat myfile.city.jsonl | cjseq filter --bbox 85007 446179 85168 446290 > mysubset.city.jsonl

Input constraints

1. the input CityJSON/Seq must be v1.1 or v2.0 (v1.0 will panic).
2. the input JSON must be CityJSON schema-valid, use cjval to validate.

WASM bindings

cjseq can be used in JavaScript/TypeScript applications via WASM bindings.

cargo install wasm-pack

Build the WASM bindings:

wasm-pack build --release --target web --out-dir js