Client Request/Response Flow

This document describes the full request/response cycle for a client that wants to:

Copy input data from shared storage into the storeBase
Run a plugin on that data
Get output file metadata
Upload output data back to shared storage (Swift only)
Delete all job data from the storeBase
Remove all containers

All endpoints are prefixed with /api/v1/.

0. Authenticate

POST /api/v1/auth-token/
Content-Type: application/json

{
  "pfcon_user": "pfcon",
  "pfcon_password": "pfcon1234"
}

Response 200 OK:

{
  "token": "<JWT>"
}

All subsequent requests include Authorization: Bearer <JWT>.

Flow for `fslink` storage

In fslink mode, data lives on a shared POSIX filesystem. Copy pulls files (resolving .chrislink files) into the storeBase. Upload is a no-op because the output is already on the shared filesystem.

1. Schedule copy job

POST /api/v1/copyjobs/
Content-Type: application/x-www-form-urlencoded

jid=<job_id>
&input_dirs=<swift_or_fs_path_1>
&input_dirs=<swift_or_fs_path_2>   (optional, repeatable)
&output_dir=<output_path>
&cpu_limit=1000                     (optional, default 1000)
&memory_limit=200                   (optional, default 200)

input_dirs: one or more paths relative to the storeBase root (e.g. home/alice/feed_42/pl-dircopy_85/data)
output_dir: path where the client expects output to land (e.g. home/alice/feed_42/pl-simplefsapp_86/data)

Response 201 Created:

{
  "compute": {
    "jid": "<job_id>",
    "image": "ghcr.io/fnndsc/pfconopjob",
    "cmd": "python -m pfcon.copy_worker /share/outgoing",
    "status": "notStarted",
    "message": "",
    "timestamp": "",
    "logs": ""
  }
}

The copy container runs asynchronously. It reads input_dirs from the shared filesystem, resolves any .chrislink files recursively, and writes the resolved tree to <storeBase>/key-<job_id>/incoming/.

2. Poll copy status

GET /api/v1/copyjobs/<job_id>/
Authorization: Bearer <JWT>

Response 200 OK:

{
  "compute": {
    "jid": "<job_id>",
    "image": "ghcr.io/fnndsc/pfconopjob",
    "cmd": "python -m pfcon.copy_worker /share/outgoing",
    "status": "finishedSuccessfully",
    "message": "",
    "timestamp": "2026-03-12T10:30:00",
    "logs": "..."
  }
}

Possible status values: notStarted, started, finishedSuccessfully, finishedWithError, undefined.

Poll until status is finishedSuccessfully or finishedWithError.

3. Schedule plugin job

POST /api/v1/pluginjobs/
Content-Type: application/x-www-form-urlencoded

jid=<job_id>
&entrypoint=python3
&entrypoint=/usr/local/bin/simplefsapp
&args=--dir
&args=/share/incoming
&auid=cube
&number_of_workers=1
&cpu_limit=1000
&memory_limit=200
&gpu_limit=0
&image=fnndsc/pl-simplefsapp
&type=fs
&input_dirs=<input_path>
&output_dir=<output_path>

entrypoint: repeatable, forms the command prefix
args: repeatable, forms the argument list
type: fs (no input mount), ds (input dir appended to cmd), or ts
input_dirs, output_dir: same paths as the copy job (used by pfcon to know where the client's data lives)

Response 201 Created:

{
  "data": {},
  "compute": {
    "jid": "<job_id>",
    "image": "fnndsc/pl-simplefsapp",
    "cmd": "python3 /usr/local/bin/simplefsapp --dir /share/incoming /share/outgoing",
    "status": "notStarted",
    "message": "",
    "timestamp": "",
    "logs": ""
  }
}

The plugin container mounts:

<storeBase>/key-<job_id>/incoming -> /share/incoming
<output_dir> -> /share/outgoing

4. Poll plugin status

GET /api/v1/pluginjobs/<job_id>/
Authorization: Bearer <JWT>

Response 200 OK:

{
  "compute": {
    "jid": "<job_id>",
    "image": "fnndsc/pl-simplefsapp",
    "cmd": "python3 /usr/local/bin/simplefsapp --dir /share/incoming /share/outgoing",
    "status": "finishedSuccessfully",
    "message": "",
    "timestamp": "2026-03-12T10:31:00",
    "logs": "..."
  }
}

5. Get output file metadata

GET /api/v1/pluginjobs/<job_id>/file/?job_output_path=<output_path>
Authorization: Bearer <JWT>

Response 200 OK (application/json):

{
  "job_output_path": "<output_path>",
  "rel_file_paths": [
    "output_file_1.txt",
    "subdir/output_file_2.txt"
  ]
}

Returns the list of relative file paths in the output directory. The client uses this to know what files the plugin produced.

6. Upload output (no-op for fslink)

POST /api/v1/uploadjobs/
Content-Type: application/x-www-form-urlencoded

jid=<job_id>
&job_output_path=<output_path>

Response 201 Created:

{
  "compute": {
    "jid": "<job_id>",
    "image": "",
    "cmd": "",
    "status": "finishedSuccessfully",
    "message": "uploadSkipped",
    "timestamp": "",
    "logs": ""
  }
}

Since the output is already on the shared filesystem, no upload container is scheduled. The response is immediate.

7. Schedule delete job

POST /api/v1/deletejobs/
Content-Type: application/x-www-form-urlencoded

jid=<job_id>

Response 201 Created:

{
  "compute": {
    "jid": "<job_id>",
    "image": "ghcr.io/fnndsc/pfconopjob",
    "cmd": "python -m pfcon.delete_worker /share/outgoing",
    "status": "notStarted",
    "message": "",
    "timestamp": "",
    "logs": ""
  }
}

The delete container removes <storeBase>/key-<job_id>/ (both incoming/ and any intermediate data).

8. Poll delete status

GET /api/v1/deletejobs/<job_id>/
Authorization: Bearer <JWT>

Response 200 OK:

{
  "compute": {
    "jid": "<job_id>",
    "image": "ghcr.io/fnndsc/pfconopjob",
    "cmd": "python -m pfcon.delete_worker /share/outgoing",
    "status": "finishedSuccessfully",
    "message": "",
    "timestamp": "2026-03-12T10:32:00",
    "logs": "..."
  }
}

9. Remove all containers

DELETE /api/v1/copyjobs/<job_id>/
Authorization: Bearer <JWT>

Response 204 No Content

DELETE /api/v1/pluginjobs/<job_id>/
Authorization: Bearer <JWT>

Response 204 No Content

DELETE /api/v1/uploadjobs/<job_id>/
Authorization: Bearer <JWT>

Response 204 No Content (no-op since no container was created)

DELETE /api/v1/deletejobs/<job_id>/
Authorization: Bearer <JWT>

Response 204 No Content

Flow for `swift` storage

In Swift mode, input data lives in OpenStack Swift object storage. Copy pulls objects from Swift into the storeBase. After the plugin runs, upload pushes output back to Swift.

1. Schedule copy job

POST /api/v1/copyjobs/
Content-Type: application/x-www-form-urlencoded

jid=<job_id>
&input_dirs=<swift_prefix_1>
&input_dirs=<swift_prefix_2>        (optional, repeatable)
&output_dir=<swift_output_prefix>

input_dirs: Swift object prefixes (e.g. home/alice/feed_42/pl-dircopy_85/data)
output_dir: Swift prefix where output will eventually be uploaded (e.g. home/alice/feed_42/pl-simplefsapp_86/data)

Response 201 Created:

{
  "compute": {
    "jid": "<job_id>",
    "image": "ghcr.io/fnndsc/pfconopjob",
    "cmd": "python -m pfcon.copy_worker /share/outgoing",
    "status": "notStarted",
    "message": "",
    "timestamp": "",
    "logs": ""
  }
}

The copy container downloads all objects matching input_dirs from Swift, resolves .chrislink files recursively, and writes the result to <storeBase>/key-<job_id>/incoming/.

2. Poll copy status

Same as fslink (see above).

3. Schedule plugin job

POST /api/v1/pluginjobs/
Content-Type: application/x-www-form-urlencoded

jid=<job_id>
&entrypoint=python3
&entrypoint=/usr/local/bin/simplefsapp
&args=--dir
&args=/share/incoming
&auid=cube
&number_of_workers=1
&cpu_limit=1000
&memory_limit=200
&gpu_limit=0
&image=fnndsc/pl-simplefsapp
&type=fs
&input_dirs=<swift_input_prefix>
&output_dir=<swift_output_prefix>

Response 201 Created:

{
  "data": {},
  "compute": {
    "jid": "<job_id>",
    "image": "fnndsc/pl-simplefsapp",
    "cmd": "python3 /usr/local/bin/simplefsapp --dir /share/incoming /share/outgoing",
    "status": "notStarted",
    "message": "",
    "timestamp": "",
    "logs": ""
  }
}

In Swift mode the plugin container mounts:

<storeBase>/key-<job_id>/incoming -> /share/incoming
<storeBase>/key-<job_id>/outgoing -> /share/outgoing

Note: unlike fslink, the output goes to a key-<job_id>/outgoing directory (not the output_dir path directly) because it still needs to be uploaded to Swift.

4. Poll plugin status

Same as fslink (see above).

5. Get output file metadata

GET /api/v1/pluginjobs/<job_id>/file/?job_output_path=<swift_output_prefix>
Authorization: Bearer <JWT>

Response 200 OK (application/json):

{
  "job_output_path": "<swift_output_prefix>",
  "rel_file_paths": [
    "output_file_1.txt",
    "subdir/output_file_2.txt"
  ]
}

6. Upload output to Swift

POST /api/v1/uploadjobs/
Content-Type: application/x-www-form-urlencoded

jid=<job_id>
&job_output_path=<swift_output_prefix>

job_output_path: the Swift prefix where output files should be uploaded

Response 201 Created:

{
  "compute": {
    "jid": "<job_id>",
    "image": "ghcr.io/fnndsc/pfconopjob",
    "cmd": "python -m pfcon.upload_worker /share/outgoing",
    "status": "notStarted",
    "message": "",
    "timestamp": "",
    "logs": ""
  }
}

The upload container reads files from <storeBase>/key-<job_id>/outgoing/ and uploads them to Swift under the job_output_path prefix.

This endpoint is idempotent: if the upload container already exists and hasn't failed, a repeated POST returns the existing container's status instead of scheduling a duplicate.

7. Poll upload status

GET /api/v1/uploadjobs/<job_id>/
Authorization: Bearer <JWT>

Response 200 OK:

{
  "compute": {
    "jid": "<job_id>",
    "image": "ghcr.io/fnndsc/pfconopjob",
    "cmd": "python -m pfcon.upload_worker /share/outgoing",
    "status": "finishedSuccessfully",
    "message": "",
    "timestamp": "2026-03-12T10:33:00",
    "logs": "..."
  }
}

8. Schedule delete job

Same as fslink (see above). Removes <storeBase>/key-<job_id>/.

9. Poll delete status

Same as fslink (see above).

10. Remove all containers

DELETE /api/v1/copyjobs/<job_id>/

Response 204 No Content

DELETE /api/v1/pluginjobs/<job_id>/

Response 204 No Content

DELETE /api/v1/uploadjobs/<job_id>/

Response 204 No Content

DELETE /api/v1/deletejobs/<job_id>/

Response 204 No Content

Sequence diagrams

fslink

Client                          pfcon                        Compute Cluster       Shared FS
  |                               |                               |                   |
  |-- POST /auth-token/ -------->|                               |                   |
  |<-------- 200 {token} --------|                               |                   |
  |                               |                               |                   |
  |-- POST /copyjobs/ ---------->|                               |                   |
  |                               |-- schedule copy container -->|                   |
  |<-------- 201 {notStarted} ---|                               |                   |
  |                               |                               |-- resolve links ->|
  |                               |                               |-- write incoming ->|
  |-- GET /copyjobs/<id>/ ------>|-- query container status ---->|                   |
  |<-------- 200 {finished} -----|                               |                   |
  |                               |                               |                   |
  |-- POST /pluginjobs/ -------->|                               |                   |
  |                               |-- schedule plugin container ->|                   |
  |<-------- 201 {notStarted} ---|                               |                   |
  |                               |                               |-- read incoming -->|
  |                               |                               |-- write outgoing ->|
  |-- GET /pluginjobs/<id>/ ---->|-- query container status ---->|                   |
  |<-------- 200 {finished} -----|                               |                   |
  |                               |                               |                   |
  |-- GET /pluginjobs/<id>/file/ >|                               |                   |
  |<-------- 200 {file list} ----|                               |                   |
  |                               |                               |                   |
  |-- POST /uploadjobs/ -------->|                               |                   |
  |<-- 201 {uploadSkipped} ------|  (no-op: output already on FS)|                   |
  |                               |                               |                   |
  |-- POST /deletejobs/ -------->|                               |                   |
  |                               |-- schedule delete container ->|                   |
  |<-------- 201 {notStarted} ---|                               |                   |
  |                               |                               |-- rm key dir ---->|
  |-- GET /deletejobs/<id>/ ---->|-- query container status ---->|                   |
  |<-------- 200 {finished} -----|                               |                   |
  |                               |                               |                   |
  |-- DELETE /copyjobs/<id>/ --->|-- remove container ---------->|                   |
  |<-------- 204 ----------------|                               |                   |
  |-- DELETE /pluginjobs/<id>/ ->|-- remove container ---------->|                   |
  |<-------- 204 ----------------|                               |                   |
  |-- DELETE /deletejobs/<id>/ ->|-- remove container ---------->|                   |
  |<-------- 204 ----------------|                               |                   |

swift

Client                          pfcon                        Compute Cluster       Swift
  |                               |                               |                  |
  |-- POST /auth-token/ -------->|                               |                  |
  |<-------- 200 {token} --------|                               |                  |
  |                               |                               |                  |
  |-- POST /copyjobs/ ---------->|                               |                  |
  |                               |-- schedule copy container -->|                  |
  |<-------- 201 {notStarted} ---|                               |                  |
  |                               |                               |-- download ----->|
  |                               |                               |   objects        |
  |                               |                               |-- resolve links  |
  |                               |                               |-- write incoming |
  |-- GET /copyjobs/<id>/ ------>|-- query container status ---->|                  |
  |<-------- 200 {finished} -----|                               |                  |
  |                               |                               |                  |
  |-- POST /pluginjobs/ -------->|                               |                  |
  |                               |-- schedule plugin container ->|                  |
  |<-------- 201 {notStarted} ---|                               |                  |
  |                               |                               |-- read incoming  |
  |                               |                               |-- write outgoing |
  |-- GET /pluginjobs/<id>/ ---->|-- query container status ---->|                  |
  |<-------- 200 {finished} -----|                               |                  |
  |                               |                               |                  |
  |-- GET /pluginjobs/<id>/file/ >|                               |                  |
  |<-------- 200 {file list} ----|                               |                  |
  |                               |                               |                  |
  |-- POST /uploadjobs/ -------->|                               |                  |
  |                               |-- schedule upload container ->|                  |
  |<-------- 201 {notStarted} ---|                               |                  |
  |                               |                               |-- upload ------->|
  |                               |                               |   objects        |
  |-- GET /uploadjobs/<id>/ ---->|-- query container status ---->|                  |
  |<-------- 200 {finished} -----|                               |                  |
  |                               |                               |                  |
  |-- POST /deletejobs/ -------->|                               |                  |
  |                               |-- schedule delete container ->|                  |
  |<-------- 201 {notStarted} ---|                               |                  |
  |                               |                               |-- rm key dir     |
  |-- GET /deletejobs/<id>/ ---->|-- query container status ---->|                  |
  |<-------- 200 {finished} -----|                               |                  |
  |                               |                               |                  |
  |-- DELETE /copyjobs/<id>/ --->|-- remove container ---------->|                  |
  |<-------- 204 ----------------|                               |                  |
  |-- DELETE /pluginjobs/<id>/ ->|-- remove container ---------->|                  |
  |<-------- 204 ----------------|                               |                  |
  |-- DELETE /uploadjobs/<id>/ ->|-- remove container ---------->|                  |
  |<-------- 204 ----------------|                               |                  |
  |-- DELETE /deletejobs/<id>/ ->|-- remove container ---------->|                  |
  |<-------- 204 ----------------|                               |                  |

Key differences between fslink and swift

Aspect	fslink	swift
Copy source	Shared POSIX filesystem	Swift object storage
Plugin output dir	`<output_dir>` (directly on shared FS)	`key-<job_id>/outgoing` (local storeBase)
Upload step	No-op (`uploadSkipped`)	Schedules upload container to push to Swift
Upload idempotency	N/A	Yes - repeated POST returns existing status
`.chrislink` resolution	Follows symlink-like files on filesystem	Downloads and follows `.chrislink` objects from Swift
Containers created	3 (copy, plugin, delete)	4 (copy, plugin, upload, delete)
Network connectivity	Containers need storeBase mount only	Copy/upload containers also need Swift network access

Concrete example: fslink with `pl-simpledsapp`

This example assumes:

The repo is cloned at /home/user/pfcon_fork
The server was started with ./make.sh -N -F fslink from that directory
pfcon is reachable at http://localhost:30006
STOREBASE defaults to /home/user/pfcon_fork/CHRIS_REMOTE_FS

Setup: create test data on the shared filesystem

STOREBASE=/home/user/pfcon_fork/CHRIS_REMOTE_FS

# Create the input folder with a test file
mkdir -p $STOREBASE/home/user/cube/test
echo "test file" > $STOREBASE/home/user/cube/test/test_file.txt

# Create a .chrislink file in home/user/cube pointing to the test folder
echo "home/user/cube/test" > $STOREBASE/home/user/cube/test.chrislink

# Create the output directory (required in fslink mode — plugin writes directly here)
mkdir -p $STOREBASE/home/user/cube_out

Resulting layout under STOREBASE:

CHRIS_REMOTE_FS/
└── home/user/cube/
    ├── test/
    │   └── test_file.txt          # content: "test file"
    └── test.chrislink             # content: "home/user/cube/test"

Step 0: Authenticate

TOKEN=$(curl -s -X POST http://localhost:30006/api/v1/auth-token/ \
  -H 'Content-Type: application/json' \
  -d '{"pfcon_user":"pfcon","pfcon_password":"pfcon1234"}' \
  | jq -r '.token')

Step 1: Schedule copy job

curl -s -X POST http://localhost:30006/api/v1/copyjobs/ \
  -H "Authorization: Bearer $TOKEN" \
  -d 'jid=chris-jid-2&input_dirs=home/user/cube&output_dir=home/user/cube_out'

Response 201 Created:

{
  "compute": {
    "jid": "chris-jid-2",
    "image": "ghcr.io/fnndsc/pfconopjob",
    "cmd": "python -m pfcon.copy_worker /share/outgoing",
    "status": "notStarted",
    "message": "",
    "timestamp": "",
    "logs": ""
  }
}

The copy worker reads home/user/cube/, finds test.chrislink, follows it to home/user/cube/test/, and writes the resolved tree to CHRIS_REMOTE_FS/key-chris-jid-2/incoming/. The test/ folder content is placed under a subdirectory named after the link file stem (test/).

Step 2: Poll copy status

curl -s http://localhost:30006/api/v1/copyjobs/chris-jid-2/ \
  -H "Authorization: Bearer $TOKEN"

Poll until status is finishedSuccessfully. At that point the storeBase contains:

CHRIS_REMOTE_FS/key-chris-jid-2/incoming/
├── test_file.txt          # from home/user/cube/test/ (direct files)
└── test/                  # resolved from test.chrislink
    └── test_file.txt

Step 3: Schedule plugin job

curl -s -X POST http://localhost:30006/api/v1/pluginjobs/ \
  -H "Authorization: Bearer $TOKEN" \
  -d 'jid=chris-jid-2
&args=--prefix
&args=le
&auid=cube
&number_of_workers=1
&cpu_limit=1000
&memory_limit=200
&gpu_limit=0
&image=fnndsc/pl-simpledsapp
&entrypoint=python3
&entrypoint=/usr/local/bin/simpledsapp
&type=ds
&input_dirs=home/user/cube
&output_dir=home/user/cube_out'

Or as a single line:

curl -s -X POST http://localhost:30006/api/v1/pluginjobs/ \
  -H "Authorization: Bearer $TOKEN" \
  -d 'jid=chris-jid-2&args=--prefix&args=le&auid=cube&number_of_workers=1&cpu_limit=1000&memory_limit=200&gpu_limit=0&image=fnndsc/pl-simpledsapp&entrypoint=python3&entrypoint=/usr/local/bin/simpledsapp&type=ds&input_dirs=home/user/cube&output_dir=home/user/cube_out'

Response 201 Created:

{
  "data": {},
  "compute": {
    "jid": "chris-jid-2",
    "image": "fnndsc/pl-simpledsapp",
    "cmd": "python3 /usr/local/bin/simpledsapp --prefix le /share/incoming /share/outgoing",
    "status": "notStarted",
    "message": "",
    "timestamp": "",
    "logs": ""
  }
}

For type=ds, pfcon appends /share/incoming /share/outgoing to the command after the plugin args. The container mounts:

CHRIS_REMOTE_FS/key-chris-jid-2/incoming → /share/incoming
CHRIS_REMOTE_FS/home/user/cube_out → /share/outgoing (output goes directly to the shared FS in fslink mode)

Step 4: Poll plugin status

curl -s http://localhost:30006/api/v1/pluginjobs/chris-jid-2/ \
  -H "Authorization: Bearer $TOKEN"

Poll until status is finishedSuccessfully.

Step 5: Get output file metadata

curl -s "http://localhost:30006/api/v1/pluginjobs/chris-jid-2/file/?job_output_path=home/user/cube_out" \
  -H "Authorization: Bearer $TOKEN"

Response 200 OK:

{
  "job_output_path": "home/user/cube_out",
  "rel_file_paths": [
    "test_file_le.txt",
    "test/test_file_le.txt"
  ]
}

Step 6: Upload output (no-op for fslink)

curl -s -X POST http://localhost:30006/api/v1/uploadjobs/ \
  -H "Authorization: Bearer $TOKEN" \
  -d 'jid=chris-jid-2&job_output_path=home/user/cube_out'

Response 201 Created:

{
  "compute": {
    "jid": "chris-jid-2",
    "image": "",
    "cmd": "",
    "status": "finishedSuccessfully",
    "message": "uploadSkipped",
    "timestamp": "",
    "logs": ""
  }
}

Output is already on the shared filesystem — no upload container is launched.

Step 7: Schedule delete job

curl -s -X POST http://localhost:30006/api/v1/deletejobs/ \
  -H "Authorization: Bearer $TOKEN" \
  -d 'jid=chris-jid-2'

Response 201 Created:

{
  "compute": {
    "jid": "chris-jid-2",
    "image": "ghcr.io/fnndsc/pfconopjob",
    "cmd": "python -m pfcon.delete_worker /share/outgoing",
    "status": "notStarted",
    "message": "",
    "timestamp": "",
    "logs": ""
  }
}

Step 8: Poll delete status

curl -s http://localhost:30006/api/v1/deletejobs/chris-jid-2/ \
  -H "Authorization: Bearer $TOKEN"

Poll until status is finishedSuccessfully. After this, CHRIS_REMOTE_FS/key-chris-jid-2/ is removed.

Step 9: Remove all containers

curl -s -X DELETE http://localhost:30006/api/v1/copyjobs/chris-jid-2/ \
  -H "Authorization: Bearer $TOKEN"
# 204 No Content

curl -s -X DELETE http://localhost:30006/api/v1/pluginjobs/chris-jid-2/ \
  -H "Authorization: Bearer $TOKEN"
# 204 No Content

curl -s -X DELETE http://localhost:30006/api/v1/deletejobs/chris-jid-2/ \
  -H "Authorization: Bearer $TOKEN"
# 204 No Content

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req_resp_flow.md

File metadata and controls

Client Request/Response Flow

0. Authenticate

Flow for fslink storage

1. Schedule copy job

2. Poll copy status

3. Schedule plugin job

4. Poll plugin status

5. Get output file metadata

6. Upload output (no-op for fslink)

7. Schedule delete job

8. Poll delete status

9. Remove all containers

Flow for swift storage

1. Schedule copy job

2. Poll copy status

3. Schedule plugin job

4. Poll plugin status

5. Get output file metadata

6. Upload output to Swift

7. Poll upload status

8. Schedule delete job

9. Poll delete status

10. Remove all containers

Sequence diagrams

fslink

swift

Key differences between fslink and swift

Concrete example: fslink with pl-simpledsapp

Setup: create test data on the shared filesystem

Step 0: Authenticate

Step 1: Schedule copy job

Step 2: Poll copy status

Step 3: Schedule plugin job

Step 4: Poll plugin status

Step 5: Get output file metadata

Step 6: Upload output (no-op for fslink)

Step 7: Schedule delete job

Step 8: Poll delete status

Step 9: Remove all containers

Flow for `fslink` storage

Flow for `swift` storage

Concrete example: fslink with `pl-simpledsapp`