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 swh-search
 ==========
 
 Search service for the Software Heritage archive.
 
 It is similar to swh-storage in what it contains,
 but provides different ways to query it: while swh-storage is mostly
 a key-value store that returns an object from a primary key,
 swh-search is focused on reverse indices, to allow finding objects that
 match some criteria; for example full-text search.
 
 Currently uses ElasticSearch, and provides only origin search (by URL and metadata)
 
 ## Dependencies
 
 - Python tests for this module include tests that cannot be run without a local
 ElasticSearch instance, so you need the ElasticSearch server executable on your
 machine (no need to have a running ElasticSearch server).
 
     - Debian-like host
 
         The elasticsearch package is required. As it's not part of debian-stable,
         [another debian repository is required to be
         configured](https://www.elastic.co/guide/en/elasticsearch/reference/current/deb.html#deb-repo)
 
     - Non Debian-like host
 
         The tests expect:
         - `/usr/share/elasticsearch/jdk/bin/java` to exist.
         - `org.elasticsearch.bootstrap.Elasticsearch` to be in java's classpath.
+- The `tree-sitter` module is required in the python venv to launch the yarn build. To install it, run:
+```bash
+pip install tree-sitter==0.19.0
+```
 - Emscripten is required for generating tree-sitter WASM module. The following commands need to be executed for the setup:
     ```bash
     cd /opt && git clone https://github.com/emscripten-core/emsdk.git && cd emsdk && \
     ./emsdk install latest && ./emsdk activate latest
     PATH="${PATH}:/opt/emsdk/upstream/emscripten"
     ```
 
     **Note:** If emsdk isn't found in the PATH, the tree-sitter cli automatically pulls `emscripten/emsdk` image from docker hub when `make ts-build-wasm` or `make ts-build` is used.
 
 
 ## Make targets
 
 Below is the list of available make targets that can be executed from the root directory of swh-search in order to build and/or execute the swh-search under various configurations:
 
 * **ts-install**: Install node_modules and emscripten SDK required for TreeSitter
 
 * **ts-generate**: Generate parser files(C and JSON) from the grammar
 
 * **ts-repl**: Starts a web based playground for the TreeSitter grammar. It's the recommended way for developing TreeSitter grammar.
 
 * **ts-dev**: Parse the `query_language/sample_query` and print the corresponding syntax expression
 along with the start and end positions of all the nodes.
 
 * **ts-dev sanitize=1**: Same as **ts-dev** but without start and end position of the nodes.
 This format is expected by TreeSitter's native test command. `sanitize=1` cleans the output
 of **ts-dev** using `sed` to achieve the desired format.
 
 * **ts-test**: executes TreeSitter's native tests
 
 * **ts-build-so**: Generates `swh_ql.so` file from the previously generated parser using py-tree-sitter
 
 * **ts-build-so**: Generates `swh_ql.wasm` file from the previously generated parser using emscripten
 
 * **ts-build**: Executes both **ts-build-so** and **ts-build-so**
-