Introduction
Symfony Filesystem Bundle
Symfony bundle integrating Flow PHP's Filesystem library with Symfony applications, providing a typed
FilesystemTable service that mounts multiple filesystems under URI protocols, pluggable factories,
console commands for managing files across mounted protocols, and first-class OpenTelemetry integration.
Installation
For detailed installation instructions, see the installation page.
Register the bundle in config/bundles.php:
return [
// ...
Flow\Bridge\Symfony\FilesystemBundle\FlowFilesystemBundle::class => ['all' => true],
];
Overview
This bundle integrates Flow PHP's Filesystem library with Symfony applications. It provides:
- Mount-protocol routing — mount filesystems under URI protocols of your choice (
file,memory,aws-s3,warehouse,archive, …) and resolve them at runtime via$table->for(...) - Pluggable filesystem factories — register custom backends with the
#[AsFilesystemFactory]attribute or a DI tag - Built-in factories —
file,memory,stdout,aws_s3, andazure_blobship out of the box - Console commands —
flow:filesystem:*(aliasflow:fs:*) forls,cat,cp,mv,rm,stat,touchagainst any configured filesystem - Telemetry integration — wrap every filesystem in
TraceableFilesystemvia OpenTelemetry - Multi-fstab support (advanced) — configure several independent
FilesystemTableservices when you really need them
Quick Start
A minimal configuration mounts one or more filesystems inside a single fstab. The fstab name is arbitrary —
the bundle auto-detects the only fstab and exposes it as Flow\Filesystem\FilesystemTable:
# config/packages/flow_filesystem.yaml
flow_filesystem:
fstabs:
default:
filesystems:
file:
type: file
memory:
type: memory
The YAML key under filesystems: (file, memory) is the mount protocol the filesystem will be
registered under. The type: field identifies which built-in (or custom) factory builds it.
Inject the table anywhere via autowiring:
use Flow\Filesystem\FilesystemTable;
final class ReportBuilder
{
public function __construct(private readonly FilesystemTable $fstab)
{
}
public function read(string $uri) : string
{
return $this->fstab->for('file')->readFrom(/* path */)->content();
}
}
FilesystemTable::for() accepts either a raw protocol string ('file', 'aws-s3', 'warehouse') or a
Path — when given a Path, the table resolves the filesystem by the path's URI scheme.
Most applications need exactly one fstab with multiple filesystems mounted under it. Multi-fstab support exists for advanced cases — see Multi-Fstab Support.
Configuration Reference
Fstabs
At least one fstab is required. Each fstab declares a set of filesystems. The YAML key under
filesystems: is the mount protocol and must match the regex /^[a-zA-Z][a-zA-Z0-9+.-]+$/ (letters,
digits, ., -, +). The type: field picks the factory that builds the filesystem.
flow_filesystem:
fstabs:
default:
filesystems:
file:
type: file
memory:
type: memory
warehouse: # mount protocol
type: aws_s3 # factory lookup key
bucket: '%env(S3_BUCKET)%'
Because protocol and type are independent, one fstab can mount the same backend multiple times under
different protocols — two S3 buckets as warehouse and archive, for example. Mount each explicitly:
flow_filesystem:
fstabs:
default:
filesystems:
warehouse:
type: aws_s3
bucket: '%env(S3_WAREHOUSE_BUCKET)%'
client_service_id: app.s3_client
archive:
type: aws_s3
bucket: '%env(S3_ARCHIVE_BUCKET)%'
client_service_id: app.s3_client
The fstab is wired as a private .flow_filesystem.fstab.<name> service and aliased to
Flow\Filesystem\FilesystemTable for autowiring.
Default Fstab
When you only have one fstab, the bundle picks it as the default automatically — no default_fstab key
needed, and the fstab name does not have to be default. Set default_fstab explicitly only when you
have multiple fstabs and the one you want as the default is not literally named default.
Telemetry
Enable telemetry per fstab to wrap every mounted filesystem with Flow\Filesystem\Telemetry\TraceableFilesystem.
You must wire a Flow\Telemetry\Telemetry service and a Psr\Clock\ClockInterface service yourself —
the bundle does NOT provide defaults.
flow_filesystem:
fstabs:
default:
telemetry:
enabled: true
telemetry_service_id: app.flow_telemetry # Required: Telemetry service ID
clock_service_id: app.system_clock # Required: PSR-20 clock service
options:
trace_streams: true # Record stream open/close in traces
collect_metrics: true # Collect read/write metrics
filesystems:
file:
type: file
memory:
type: memory
With telemetry.enabled: false (the default) the fstab is wired without any telemetry overhead.
Built-in Filesystems
The bundle ships with factories for these types out of the box:
type |
Options | Notes |
|---|---|---|
file |
none | Local filesystem via native PHP calls. |
memory |
none | In-memory filesystem, lifetime of the kernel. |
stdout |
none | Write-only sink that targets STDOUT. |
aws_s3 |
bucket, client*, options |
Requires flow-php/filesystem-async-aws-bridge. |
azure_blob |
container, client*, options |
Requires flow-php/filesystem-azure-bridge. |
Each entry under filesystems: is resolved against a registered FilesystemFactory by its type()
value. To introduce a new type, register your own factory (see Custom Filesystem Factory).
AWS S3
Install the bridge:
composer require flow-php/filesystem-async-aws-bridge
Mode A — bring your own AsyncAws\S3\S3Client:
flow_filesystem:
fstabs:
default:
filesystems:
aws-s3:
type: aws_s3
bucket: my-bucket
client_service_id: app.async_aws_s3_client
Mode B — inline client config:
flow_filesystem:
fstabs:
default:
filesystems:
aws-s3:
type: aws_s3
bucket: my-bucket
client:
region: '%env(AWS_REGION)%'
access_key_id: '%env(AWS_ACCESS_KEY_ID)%'
access_key_secret: '%env(AWS_SECRET_ACCESS_KEY)%'
endpoint: ~ # optional, MinIO/R2/Scaleway/LocalStack
path_style_endpoint: false
profile: ~
debug: false
http_client_service_id: ~
logger_service_id: ~
options:
block_size: 6291456
Any null client.* key is omitted from the underlying AsyncAws resolution chain, so environment-based
credential discovery still works.
Azure Blob Storage
Install the bridge:
composer require flow-php/filesystem-azure-bridge
Mode A — bring your own Flow\Azure\SDK\BlobServiceInterface:
flow_filesystem:
fstabs:
default:
filesystems:
azure-blob:
type: azure_blob
container: my-container
client_service_id: app.azure_blob_service
Mode B — inline client config (shared key auth):
flow_filesystem:
fstabs:
default:
filesystems:
azure-blob:
type: azure_blob
container: my-container
client:
account_name: '%env(AZURE_ACCOUNT_NAME)%'
auth:
shared_key: '%env(AZURE_ACCOUNT_KEY)%'
url_factory: # optional, e.g. Azurite
host: 127.0.0.1
port: '10000'
https: false
http_client_service: ~ # optional PSR-18 client
request_factory_service: ~ # optional PSR-17 request factory
stream_factory_service: ~ # optional PSR-17 stream factory
logger_service_id: ~ # optional PSR-3 logger
options:
block_size: 4194304
list_blob_max_results: 100
SAS token auth is not supported yet.
Console Commands
The bundle ships a small set of flow:filesystem:* console commands that operate on any mounted
filesystem. Unlike league/flysystem-bundle, which does not provide any CLI tools, these commands are a
Flow-specific differentiator: you can inspect, read, write, copy, move, and delete files across mounted
protocols straight from bin/console.
Each command also has a shorter flow:fs:* alias (e.g. flow:fs:ls).
Filesystem Commands
| Command | Description |
|---|---|
flow:filesystem:ls |
List entries under a directory URI |
flow:filesystem:cat |
Stream a file URI to STDOUT |
flow:filesystem:cp |
Copy a file between two URIs |
flow:filesystem:mv |
Move a file between two URIs (copy + delete source) |
flow:filesystem:rm |
Remove a file or directory |
flow:filesystem:stat |
Print metadata about a file or directory URI |
flow:filesystem:touch |
Create an empty file at a URI |
Common options:
| Option | Description |
|---|---|
--fstab (-f) |
(advanced) Target a specific fstab when more than one is configured; defaults to the bundle default fstab |
Per-command options:
| Command | Options |
|---|---|
ls |
--recursive (-r), --short (-s), --limit=N, --offset=N, --page-size=N, --format=json |
rm |
--recursive (-r) — required for directories |
stat |
--format=json |
touch |
--force (-F) — overwrite existing file with empty content |
ls output
By default ls prints a table with Type, Size, Modified, URI columns. Size is formatted
with binary units (3.12 MiB, 2.50 KiB, raw bytes below 1 KiB). Modified is ISO-8601. Both come from
the backend's listing response — no per-file HEAD or GET is issued.
--shortdrops the metadata columns, leaves only URI.--format=jsonemits newline-delimited JSON (NDJSON), one object per line — pipe-friendly for scripting.
Results are always paginated in tables of --page-size rows (default 10). When stdout is attached
to an interactive terminal, ls prompts between pages with "Show next N entries? [yes/no] (yes)" —
Enter continues, no stops. Piped or redirected output flows all pages continuously without prompting.
--limit=N caps total entries (no cap by default). When limit is reached, the command emits a
truncated warning and skips the page prompt. --offset=N skips the first N entries before listing;
note that offset is client-side, so on S3 the backend still walks the skipped keys — deep offsets on
huge buckets are slow.
stat output
stat prints a definition list with URI, Protocol, Path, Type, Size (human-readable), and Modified.
Same metadata source as ls --long (now default) — the backend's single status() call, no extra
stream opened. Pattern paths (memory://*.txt, **/*.parquet) are rejected with a clear error.
URI Format
Path arguments are full URIs in the form <protocol>://<path>. When a protocol is omitted, the bundle
assumes the local filesystem (file://) and resolves relative paths against the current working directory:
bin/console flow:filesystem:ls ./reports # → file:///<cwd>/reports
bin/console flow:filesystem:ls /var/log # → file:///var/log
bin/console flow:filesystem:ls memory://reports # explicit protocol
Examples
# Paginated table with type/size/modified; press Enter to go through pages
bin/console flow:filesystem:ls aws-s3://bucket/
# Top 50 entries only, skipping the first 20
bin/console flow:filesystem:ls aws-s3://bucket/ --offset=20 --limit=50
# Larger pages for a bigger terminal
bin/console flow:filesystem:ls aws-s3://bucket/ --page-size=50
# URI-only output, piped into another command
bin/console flow:filesystem:ls aws-s3://bucket/ --short --limit=1000 | sort
# NDJSON for scripts
bin/console flow:filesystem:ls aws-s3://bucket/ --format=json | jq '.uri'
bin/console flow:filesystem:cat file:///tmp/dump.csv
bin/console flow:filesystem:cp memory://staging/out.parquet file:///var/lib/flow/out.parquet
bin/console flow:filesystem:mv memory://tmp/result.json aws-s3://bucket/result.json
bin/console flow:filesystem:rm file:///var/cache/flow --recursive
bin/console flow:filesystem:stat aws-s3://bucket/key.bin --format=json
bin/console flow:filesystem:touch file:///tmp/.flow_smoke_test
cp / mv work across protocols, not across fstabs
cp and mv happily copy between any two protocols mounted in the same fstab — e.g.
memory://… → aws-s3://… or file:///… → azure-blob://…. Internally they use the
Flow\Filesystem\Operations\Copy / Move operations which stream in 8 KiB chunks by default, so large
files don't blow up memory. Same-filesystem moves (e.g. aws-s3://a → aws-s3://b) use the backend's
native mv for server-side optimizations (rename on local, CopyObject+DeleteObject on S3,
CopyBlob+DeleteBlob on Azure).
Cross-filesystem mv is not atomic: if the source removal fails after a successful write, the
destination is present and the source remains; re-running is idempotent.
What these commands do not do is bridge two separate fstabs: source and destination must resolve
through the same FilesystemTable. Since most apps use a single fstab with everything mounted under it,
this is rarely a real constraint. If you genuinely need to move data between two fstabs, run two
commands and stage through a temporary location:
bin/console flow:filesystem:cp aws-s3://bucket/file.csv file:///tmp/file.csv --fstab=warehouse
bin/console flow:filesystem:cp file:///tmp/file.csv azure-blob://container/file.csv --fstab=archive
mkdir is intentionally absent
Remote object stores (S3, Azure Blob, …) do not have a real concept of directories — they expose flat
keyspaces with / as a convention. Rather than emulate mkdir inconsistently across backends, the bundle
omits the command entirely. Directories appear when files appear inside them.
Multi-Fstab Support
Advanced. Most applications should stick to a single fstab with multiple filesystems mounted under it. Reach for multi-fstab only when you need fully isolated tables — e.g. strict separation between read-only archive storage and a read/write working area, or two completely independent configurations that should never bleed across to one another.
The bundle supports multiple independent fstabs, each with its own protocol keyspace:
flow_filesystem:
default_fstab: primary
fstabs:
primary:
filesystems:
file:
type: file
analytics:
filesystems:
memory:
type: memory
file:
type: file
archive:
filesystems:
aws-s3:
type: aws_s3
bucket: '%env(ARCHIVE_BUCKET)%'
Each fstab gets its own .flow_filesystem.fstab.<name> service. The default fstab is automatically aliased
to Flow\Filesystem\FilesystemTable, allowing direct type-hint injection without specifying a fstab name.
Each named fstab is also aliased as Flow\Filesystem\FilesystemTable $<camelCasedName>Fstab for
named-argument autowiring:
use Flow\Filesystem\FilesystemTable;
final class ReportBuilder
{
public function __construct(
private readonly FilesystemTable $fstab, // → primary (default)
private readonly FilesystemTable $analyticsFstab, // → analytics
private readonly FilesystemTable $archiveFstab, // → archive
) {
}
public function read() : string
{
return $this->fstab->for('file')->readFrom(/* path */)->content();
}
}
Target a specific fstab with any console command:
bin/console flow:filesystem:ls aws-s3://bucket/reports --fstab=archive
Custom Filesystem Factory
The bundle has no concept of "custom" filesystems — every filesystem is created by a FilesystemFactory.
To plug in your own backend, implement
Flow\Bridge\Symfony\FilesystemBundle\Filesystem\FilesystemFactory:
namespace App\Flow;
use Flow\Bridge\Symfony\FilesystemBundle\Filesystem\FilesystemFactory;
use Flow\Filesystem\Filesystem;
final class MyFilesystemFactory implements FilesystemFactory
{
public function type() : string
{
return 'my_backend';
}
public function create(string $protocol, array $config) : Filesystem
{
// $protocol is the YAML key (mount protocol) the user chose.
// $config is the array under filesystems.<protocol> in YAML with `type` already stripped.
}
}
type() returns the factory lookup key — it's what users put under type: in YAML. The mount protocol
is a separate concept and comes from the YAML key (passed to create() as $protocol).
There are two ways to register the factory.
Attribute-Based Discovery
Annotate the factory class with #[AsFilesystemFactory] for automatic discovery:
namespace App\Flow;
use Flow\Bridge\Symfony\FilesystemBundle\Attribute\AsFilesystemFactory;
use Flow\Bridge\Symfony\FilesystemBundle\Filesystem\FilesystemFactory;
use Flow\Filesystem\Filesystem;
#[AsFilesystemFactory(type: 'my_backend')]
final class MyFilesystemFactory implements FilesystemFactory
{
public function type() : string { return 'my_backend'; }
public function create(string $protocol, array $config) : Filesystem { /* ... */ }
}
As long as your service is autoconfigured (the default in services.yaml for everything under your App\
namespace), the bundle automatically attaches the flow_filesystem.factory tag with the right type
attribute.
Explicit Tag
Useful if your factory lives in a service that doesn't have autoconfigure enabled (e.g. third-party namespaces, manual definitions):
services:
app.flow_filesystem.factory.my_backend:
class: App\Flow\MyFilesystemFactory
tags:
- { name: flow_filesystem.factory, type: my_backend }
Either way, you can then mount the backend under any protocol in any fstab:
flow_filesystem:
fstabs:
default:
filesystems:
my-mount:
type: my_backend
foo: bar # arbitrary options handed to the factory's create()
Notes:
- The
typeattribute on the tag (or on#[AsFilesystemFactory]) must matchtype()exactly. - A
typecan be served by exactly one factory; registering two factories for the same type fails at compile time. - Within a single fstab, a mount protocol (the YAML key under
filesystems:) can be used exactly once — this is enforced byFilesystemTableitself. To mount the same backend twice with different options (e.g. two S3 buckets), use two distinct mount protocols pointing to the sametype.
Comparison with league/flysystem-bundle
- Multi-fstab: each fstab is an independent
FilesystemTableservice with its own protocol keyspace. Flysystem Bundle wires individual filesystems keyed only by name. - Mount-protocol routing: filesystems inside a fstab are resolved at runtime via
$table->for('warehouse')/$table->for($path), so application code can hand-off across protocols without knowing service ids. - Factory tag: filesystem types are pluggable via a standard
flow_filesystem.factoryDI tag; third-party libraries can ship their own factory without bundle changes. - CLI commands:
flow:filesystem:*ship with the bundle and operate on any configured fstab. Flysystem Bundle does not ship any console commands. - Telemetry first-class: OTel
TraceableFilesystemis wired by simply togglingtelemetry.enabled: trueper fstab. - No autoconfigure magic: every tagged service and compiler-pass action is explicit, matching the Symfony 6.4+/7.4+/8.0+ bundle best practices.
Complete Example
A typical single-fstab setup with local + S3 mounts and telemetry enabled:
# config/packages/flow_filesystem.yaml
flow_filesystem:
fstabs:
default:
telemetry:
enabled: true
telemetry_service_id: app.flow_telemetry
clock_service_id: app.system_clock
options:
trace_streams: true
collect_metrics: true
filesystems:
file:
type: file
memory:
type: memory
aws-s3:
type: aws_s3
bucket: '%env(S3_BUCKET)%'
client:
region: '%env(AWS_REGION)%'
access_key_id: '%env(AWS_ACCESS_KEY_ID)%'
access_key_secret: '%env(AWS_SECRET_ACCESS_KEY)%'
options:
block_size: 6291456