server: add server with git history.

server/.gitignore

@@ -0,0 +1,5 @@
+# Ignore the default AAS storage directory
+storage/
+
+# Ignore PyCharm IDE configuration
+.idea

server/Dockerfile

@@ -0,0 +1,45 @@
+FROM python:3.11-alpine
+
+LABEL org.label-schema.name="Eclipse BaSyx" \
+      org.label-schema.version="1.0" \
+      org.label-schema.description="Docker image for the basyx-python-sdk server application" \
+      org.label-schema.maintainer="Eclipse BaSyx"
+
+ENV PYTHONDONTWRITEBYTECODE=1
+ENV PYTHONUNBUFFERED=1
+
+# If we have more dependencies for the server it would make sense
+# to refactor uswgi to the pyproject.toml
+RUN apk update && \
+    apk add --no-cache nginx supervisor gcc musl-dev linux-headers python3-dev git bash && \
+    pip install uwsgi && \
+    pip install --no-cache-dir git+https://github.com/eclipse-basyx/basyx-python-sdk@main#subdirectory=sdk && \
+    apk del git bash
+
+
+COPY uwsgi.ini /etc/uwsgi/
+COPY supervisord.ini /etc/supervisor/conf.d/supervisord.ini
+COPY stop-supervisor.sh /etc/supervisor/stop-supervisor.sh
+RUN chmod +x /etc/supervisor/stop-supervisor.sh
+
+# Makes it possible to use a different configuration
+ENV UWSGI_INI=/etc/uwsgi/uwsgi.ini
+# object stores aren't thread-safe yet
+# https://github.com/eclipse-basyx/basyx-python-sdk/issues/205
+ENV UWSGI_CHEAPER=0
+ENV UWSGI_PROCESSES=1
+ENV NGINX_MAX_UPLOAD=1M
+ENV NGINX_WORKER_PROCESSES=1
+ENV LISTEN_PORT=80
+ENV CLIENT_BODY_BUFFER_SIZE=1M
+
+# Copy the entrypoint that will generate Nginx additional configs
+COPY entrypoint.sh /entrypoint.sh
+RUN chmod +x /entrypoint.sh
+
+ENTRYPOINT ["/entrypoint.sh"]
+
+COPY ./app /app
+WORKDIR /app
+
+CMD ["/usr/bin/supervisord", "-c", "/etc/supervisor/conf.d/supervisord.ini"]

server/README.md

@@ -0,0 +1,74 @@
+# Eclipse BaSyx Python SDK - HTTP Server
+
+This repository contains a Dockerfile to spin up an exemplary HTTP/REST server following the [Specification of the AAS Part 2 API][6] with ease.
+The server currently implements the following interfaces:
+
+- [Asset Administration Shell Repository Service][4]
+- [Submodel Repository Service][5]
+
+It uses the [HTTP API][1] and the [AASX][7], [JSON][8], and [XML][9] Adapters of the [BaSyx Python SDK][3], to serve regarding files from a given directory.
+The files are only read, chages won't persist.
+
+Alternatively, the container can also be told to use the [Local-File Backend][2] instead, which stores AAS and Submodels as individual JSON files and allows for persistent changes (except supplementary files, i.e. files referenced by `File` submodel elements).
+See [below](#options) on how to configure this.
+
+## Building
+The container image can be built via:
+```
+$ docker buildx build -t basyx-python-sdk-http-server .
+```
+
+## Running
+
+### Storage
+The container needs to be provided with the directory `/storage` to store AAS and Submodel files: AASX, JSON, XML or JSON files of Local-File Backend.
+
+This directory can be mapped via the `-v` option from another image or a local directory.
+To map the directory `storage` inside the container, `-v ./storage:/storage` can be used.
+The directory `storage` will be created in the current working directory, if it doesn't already exist.
+
+### Port
+The HTTP server inside the container listens on port 80 by default.
+To expose it on the host on port 8080, use the option `-p 8080:80` when running it.
+
+### Options
+The container can be configured via environment variables:
+- `API_BASE_PATH` determines the base path under which all other API paths are made available.
+  Default: `/api/v3.0`
+- `STORAGE_TYPE` can be one of `LOCAL_FILE_READ_ONLY` or `LOCAL_FILE_BACKEND`:
+  - When set to `LOCAL_FILE_READ_ONLY` (the default), the server will read and serve AASX, JSON, XML files from the storage directory.
+    The files are not modified, all changes done via the API are only stored in memory.
+  - When instead set to `LOCAL_FILE`, the server makes use of the [LocalFileBackend][2], where AAS and Submodels are persistently stored as JSON files.
+    Supplementary files, i.e. files referenced by `File` submodel elements, are not stored in this case.
+- `STORAGE_PATH` sets the directory to read the files from *within the container*. If you bind your files to a directory different from the default `/storage`, you can use this variable to adjust the server accordingly.
+
+### Running Examples
+
+Putting it all together, the container can be started via the following command:
+```
+$ docker run -p 8080:80 -v ./storage:/storage basyx-python-sdk-http-server
+```
+
+Since Windows uses backslashes instead of forward slashes in paths, you'll have to adjust the path to the storage directory there:
+```
+> docker run -p 8080:80 -v .\storage:/storage basyx-python-sdk-http-server
+```
+
+Per default, the server will use the `LOCAL_FILE_READ_ONLY` storage type and serve the API under `/api/v3.0` and read files from `/storage`. If you want to change this, you can do so like this:
+```
+$ docker run -p 8080:80 -v ./storage2:/storage2 -e API_BASE_PATH=/api/v3.1 -e STORAGE_TYPE=LOCAL_FILE_BACKEND -e STORAGE_PATH=/storage2 basyx-python-sdk-http-server
+```
+## Acknowledgments
+
+This Dockerfile is inspired by the [tiangolo/uwsgi-nginx-docker][10] repository.
+
+[1]: https://github.com/eclipse-basyx/basyx-python-sdk/pull/238
+[2]: https://basyx-python-sdk.readthedocs.io/en/latest/backend/local_file.html
+[3]: https://github.com/eclipse-basyx/basyx-python-sdk
+[4]: https://app.swaggerhub.com/apis/Plattform_i40/AssetAdministrationShellRepositoryServiceSpecification/V3.0.1_SSP-001
+[5]: https://app.swaggerhub.com/apis/Plattform_i40/SubmodelRepositoryServiceSpecification/V3.0.1_SSP-001
+[6]: https://industrialdigitaltwin.org/content-hub/aasspecifications/idta_01002-3-0_application_programming_interfaces
+[7]: https://basyx-python-sdk.readthedocs.io/en/latest/adapter/aasx.html#adapter-aasx
+[8]: https://basyx-python-sdk.readthedocs.io/en/latest/adapter/json.html
+[9]: https://basyx-python-sdk.readthedocs.io/en/latest/adapter/xml.html
+[10]: https://github.com/tiangolo/uwsgi-nginx-docker

server/app/main.py

@@ -0,0 +1,46 @@
+import os
+import pathlib
+import sys
+
+from basyx.aas import model, adapter
+from basyx.aas.adapter import aasx
+
+from basyx.aas.backend.local_file import LocalFileObjectStore
+from basyx.aas.adapter.http import WSGIApp
+
+storage_path = os.getenv("STORAGE_PATH", "/storage")
+storage_type = os.getenv("STORAGE_TYPE", "LOCAL_FILE_READ_ONLY")
+base_path = os.getenv("API_BASE_PATH")
+
+wsgi_optparams = {}
+
+if base_path is not None:
+    wsgi_optparams["base_path"] = base_path
+
+if storage_type == "LOCAL_FILE_BACKEND":
+    application = WSGIApp(LocalFileObjectStore(storage_path), aasx.DictSupplementaryFileContainer(), **wsgi_optparams)
+
+elif storage_type in "LOCAL_FILE_READ_ONLY":
+    object_store: model.DictObjectStore = model.DictObjectStore()
+    file_store: aasx.DictSupplementaryFileContainer = aasx.DictSupplementaryFileContainer()
+
+    for file in pathlib.Path(storage_path).iterdir():
+        if not file.is_file():
+            continue
+        print(f"Loading {file}")
+
+        if file.suffix.lower() == ".json":
+            with open(file) as f:
+                adapter.json.read_aas_json_file_into(object_store, f)
+        elif file.suffix.lower() == ".xml":
+            with open(file) as f:
+                adapter.xml.read_aas_xml_file_into(object_store, file)
+        elif file.suffix.lower() == ".aasx":
+            with aasx.AASXReader(file) as reader:
+                reader.read_into(object_store=object_store, file_store=file_store)
+
+    application = WSGIApp(object_store, file_store, **wsgi_optparams)
+
+else:
+    print(f"STORAGE_TYPE must be either LOCAL_FILE or LOCAL_FILE_READ_ONLY! Current value: {storage_type}",
+          file=sys.stderr)

server/compose.yml

@@ -0,0 +1,7 @@
+services:
+  app:
+    build: .
+    ports:
+    - "8080:80"
+    volumes:
+      - ./storage:/storage

server/entrypoint.sh

@@ -0,0 +1,71 @@
+#!/usr/bin/env sh
+set -e
+
+# Get the maximum upload file size for Nginx, default to 0: unlimited
+USE_NGINX_MAX_UPLOAD=${NGINX_MAX_UPLOAD:-0}
+
+# Get the number of workers for Nginx, default to 1
+USE_NGINX_WORKER_PROCESSES=${NGINX_WORKER_PROCESSES:-1}
+
+# Set the max number of connections per worker for Nginx, if requested
+# Cannot exceed worker_rlimit_nofile, see NGINX_WORKER_OPEN_FILES below
+NGINX_WORKER_CONNECTIONS=${NGINX_WORKER_CONNECTIONS:-1024}
+
+# Get the listen port for Nginx, default to 80
+USE_LISTEN_PORT=${LISTEN_PORT:-80}
+
+# Get the client_body_buffer_size for Nginx, default to 1M
+USE_CLIENT_BODY_BUFFER_SIZE=${CLIENT_BODY_BUFFER_SIZE:-1M}
+
+# Create the conf.d directory if it doesn't exist
+if [ ! -d /etc/nginx/conf.d ]; then
+    mkdir -p /etc/nginx/conf.d
+fi
+
+if [ -f /app/nginx.conf ]; then
+    cp /app/nginx.conf /etc/nginx/nginx.conf
+else
+    content='user  nginx;\n'
+    # Set the number of worker processes in Nginx
+    content=$content"worker_processes ${USE_NGINX_WORKER_PROCESSES};\n"
+    content=$content'error_log  /var/log/nginx/error.log warn;\n'
+    content=$content'pid        /var/run/nginx.pid;\n'
+    content=$content'events {\n'
+    content=$content"    worker_connections ${NGINX_WORKER_CONNECTIONS};\n"
+    content=$content'}\n'
+    content=$content'http {\n'
+    content=$content'    include       /etc/nginx/mime.types;\n'
+    content=$content'    default_type  application/octet-stream;\n'
+    content=$content'    log_format  main  '"'\$remote_addr - \$remote_user [\$time_local] \"\$request\" '\n"
+    content=$content'                      '"'\$status \$body_bytes_sent \"\$http_referer\" '\n"
+    content=$content'                      '"'\"\$http_user_agent\" \"\$http_x_forwarded_for\"';\n"
+    content=$content'    access_log  /var/log/nginx/access.log  main;\n'
+    content=$content'    sendfile        on;\n'
+    content=$content'    keepalive_timeout  65;\n'
+    content=$content'    include /etc/nginx/conf.d/*.conf;\n'
+    content=$content'}\n'
+    content=$content'daemon off;\n'
+    # Set the max number of open file descriptors for Nginx workers, if requested
+    if [ -n "${NGINX_WORKER_OPEN_FILES}" ] ; then
+        content=$content"worker_rlimit_nofile ${NGINX_WORKER_OPEN_FILES};\n"
+    fi
+    # Save generated /etc/nginx/nginx.conf
+    printf "$content" > /etc/nginx/nginx.conf
+
+    content_server='server {\n'
+    content_server=$content_server"    listen ${USE_LISTEN_PORT};\n"
+    content_server=$content_server'    location / {\n'
+    content_server=$content_server'        include uwsgi_params;\n'
+    content_server=$content_server'        uwsgi_pass unix:///tmp/uwsgi.sock;\n'
+    content_server=$content_server'    }\n'
+    content_server=$content_server'}\n'
+    # Save generated server /etc/nginx/conf.d/nginx.conf
+    printf "$content_server" > /etc/nginx/conf.d/nginx.conf
+
+    # # Generate additional configuration
+    printf "client_max_body_size $USE_NGINX_MAX_UPLOAD;\n" > /etc/nginx/conf.d/upload.conf
+    printf "client_body_buffer_size $USE_CLIENT_BODY_BUFFER_SIZE;\n" > /etc/nginx/conf.d/body-buffer-size.conf
+    printf "add_header Access-Control-Allow-Origin *;\n" > /etc/nginx/conf.d/cors-header.conf
+fi
+
+exec "$@"

server/stop-supervisor.sh

@@ -0,0 +1,8 @@
+#!/usr/bin/env sh
+
+printf "READY\n"
+
+while read line; do
+  echo "Processing Event: $line" >&2
+  kill $PPID
+done < /dev/stdin

server/supervisord.ini

@@ -0,0 +1,27 @@
+[supervisord]
+nodaemon=true
+
+[program:uwsgi]
+command=/usr/local/bin/uwsgi --ini /etc/uwsgi/uwsgi.ini
+stdout_logfile=/dev/stdout
+stdout_logfile_maxbytes=0
+stderr_logfile=/dev/stderr
+stderr_logfile_maxbytes=0
+startsecs = 0
+autorestart=false
+# may make sense to have autorestart enabled in production
+
+[program:nginx]
+command=/usr/sbin/nginx
+stdout_logfile=/var/log/nginx.out.log
+stdout_logfile_maxbytes=0
+stderr_logfile=/var/log/nginx.err.log
+stderr_logfile_maxbytes=0
+stopsignal=QUIT
+startsecs = 0
+autorestart=false
+# may make sense to have autorestart enabled in production
+
+[eventlistener:quit_on_failure]
+events=PROCESS_STATE_STOPPED,PROCESS_STATE_EXITED,PROCESS_STATE_FATAL
+command=/etc/supervisor/stop-supervisor.sh

server/uwsgi.ini

@@ -0,0 +1,9 @@
+[uwsgi]
+wsgi-file = /app/main.py
+socket = /tmp/uwsgi.sock
+chown-socket = nginx:nginx
+chmod-socket = 664
+hook-master-start = unix_signal:15 gracefully_kill_them_all
+need-app = true
+die-on-term = true
+show-config = false