Storage Backends Reference

One-liner: cassettes are files on disk, serialized as YAML (default), JSON, or nowhere at all (Blackhole).

On this page: yaml · json · blackhole · Cassette file naming

Select via setStorage(). All three implement PurgeableStorage, so all three work with MODE_ALL.

yaml

• Default.
• One YAML list entry per recording, appended as it's recorded — streamed one record at a time rather than parsed whole into memory.

-
    request:
        method: GET
        url: 'http://example.com/hello'
        headers:
            Host: example.com
    response:
        status: { code: 200, message: OK }
        headers: { Content-Type: text/plain }
        body: 'Hello, php-vcr!'
    index: 0

⚠️ Warning: very large requests/responses can hit a PCRE backtrack-limit segfault in Symfony's YAML parser. Raise pcre.backtrack_limit in php.ini, or switch to json.

json

• Pretty-printed JSON array, parsed/written incrementally (character-by-character) rather than all at once.

[
    {
        "request": { "method": "GET", "url": "http:\/\/example.com\/hello", "headers": { "Host": "example.com" } },
        "response": { "status": { "code": 200, "message": "OK" }, "body": "Hello, php-vcr!" },
        "index": 0
    }
]

blackhole

• Discards everything. storeRecording() and purge() are no-ops, isNew() always returns true, and the iterator is always empty — nothing is ever replayed.

📌 Note: unlike yaml/json, Blackhole never touches the filesystem at all — no cassette file is created, even after insertCassette().

• Useful for smoke-testing library-hook behaviour without leaving cassette files behind.

Cassette file naming

• The file is named exactly the cassette name passed to insertCassette() — no .yml/.json extension is appended automatically.
• A cassette name containing a path separator (e.g. 'api/users') auto-creates the subfolder under the configured cassette path.
• Every recorded entry carries an index (see Cassettes → identical requests).

---

← Library Hooks · Next: Events →