### S3ProxyServer Command-Line Example

Source: https://github.com/eclipse-californium/californium/blob/main/demo-apps/cf-s3-proxy-server/README.md

Example of starting the S3ProxyServer with file storage, device credentials, and user management. This configuration enables graceful restart and specifies a maximum age for stored data.

```bash
S3ProxyServer --store-file dtls.bin --store-max-age 168 \
                --store-password64 ZVhiRW5pdkx1RUs2dmVoZg== \
                --device-file devices.txt --user-file users.txt \
                --https-credentials . --s3-config ~/.s3cfg
```

--------------------------------

### GET Request Example

Source: https://github.com/eclipse-californium/californium/blob/main/demo-apps/cf-simplefile-server/README.md

Example of how to perform a GET request to retrieve a file using the cf-helloworld-client. This retrieves 'file.bin' from the server's file root.

```sh
java -jar cf-helloworld-client-<version>.jar GETClient coap://localhost/data/file.bin file2save.bin
```

--------------------------------

### Start ExampleProxy2HttpClient

Source: https://github.com/eclipse-californium/californium/blob/main/demo-apps/cf-proxy2/README.md

Launches an example HTTP client on the same host as the proxy. This is used to interact with the proxy's HTTP endpoint.

```shell
java -jar cf-proxy2-<version>.jar ExampleProxy2HttpClient
```

--------------------------------

### Start ExampleSecureProxy2 with COAPS

Source: https://github.com/eclipse-californium/californium/blob/main/demo-apps/cf-proxy2/README.md

Starts the example cross-proxy with a co-located COAPS destination server. This is for testing secure CoAP communication.

```shell
java -jar cf-proxy2-<version>.jar ExampleSecureProxy2 coaps
```

--------------------------------

### Start ExampleCrossProxy2 with CoAP and HTTP

Source: https://github.com/eclipse-californium/californium/blob/main/demo-apps/cf-proxy2/README.md

Starts the example cross-proxy with co-located coap and http destination servers. This command is used to initiate the proxy service for testing.

```shell
java -jar cf-proxy2-<version>.jar ExampleCrossProxy2 coap http
```

--------------------------------

### Start ExampleProxy2CoapClient

Source: https://github.com/eclipse-californium/californium/blob/main/demo-apps/cf-proxy2/README.md

Launches an example CoAP client on the same host as the proxy. This is used to interact with the proxy's CoAP endpoint.

```shell
java -jar cf-proxy2-<version>.jar ExampleProxy2CoapClient
```

--------------------------------

### Start S3ProxyServer with Help

Source: https://github.com/eclipse-californium/californium/blob/main/demo-apps/cf-s3-proxy-server/README.md

Demonstrates how to start the S3ProxyServer and display its help message to view available command-line options.

```bash
java -jar cf-s3-proxy-server-<version>.jar -h
```

--------------------------------

### DemoServer Example: With HTTPS Service

Source: https://github.com/eclipse-californium/californium/blob/main/demo-apps/cf-cloud-demo-server/README.md

Starts the DemoServer with device credentials, DTLS graceful restart, and an HTTP server on port 8080 using certificates from the current directory.

```sh
DemoServer --store-file dtls.bin --store-max-age 168 \
                --store-password64 ZVhiRW5pdkx1RUs2dmVoZg== \
                --device-file devices.txt --https-credenitals .
```

--------------------------------

### s3cmd Configuration Example

Source: https://github.com/eclipse-californium/californium/blob/main/demo-apps/cf-s3-proxy-server/service/cloud-installs/README.md

Example configuration for s3cmd, including host details, bucket name, and access keys. This file is used by the install script to access S3.

```bash
[default]
host_base = sos-de-fra-1.exo.io
host_bucket = %(bucket)s.sos-de-fra-1.exo.io
bucket = cali-demo-<your domain>
access_key = EXO<your API access key>
secret_key = <your API secret key>
use_https = true
```

--------------------------------

### Reverse Proxy GET Examples

Source: https://github.com/eclipse-californium/californium/blob/main/demo-apps/cf-proxy2/README.md

Demonstrates reverse proxy GET requests to different destinations, showing successful responses and etag information.

```sh
Reverse-Proxy GET: coap://localhost/targets/destination1
etag: 0x4D4B9060
2.05/CONTENT --- Hi! I am the coap server on port 5685. Request 1.
Reverse-Proxy GET: coap://localhost/targets/destination2
etag: 'cb329225', 0x6362333239323235
```

--------------------------------

### Device Store Configuration Example

Source: https://github.com/eclipse-californium/californium/blob/main/demo-apps/cf-cloud-demo-server/README.md

Example of a device store configuration file, demonstrating how to define devices and their associated credentials (PSK, RPK, x509).

```text
# Device store for Cloud Demo

Demo.10034780012=Thing
.label=My Demo Weatherstation
# default openssl PSK credentials
.psk='Client_identity',c2VjcmV0UFNL
# Californium demo-client RPK certificate
.rpk=MFkwEwYHKoZIzj0CAQYIKoZIzj0DAQcDQgAEQxYO5/M5ie6+3QPOaAy5MD6CkFILZwIb2rOBCX/EWPaocX1H+eynUnaEEbmqxeN6rnI/pH19j4PtsegfHLrzzQ==

Demo.10560970055=Thing
.psk='cali.0012345','secretPSK'

# x509 CA (trust root)
ca.1=Admin
.type=ca
.x509=
----BEGIN CERTIFICATE-----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-----END CERTIFICATE-----

# x509 device certificate, signed by Ca
Demo.40145780125=Thing
.label=Door
.x509=
-----BEGIN CERTIFICATE-----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-----END CERTIFICATE-----

```

--------------------------------

### Install Application on Kubernetes

Source: https://github.com/eclipse-californium/californium/blob/main/demo-apps/cf-extplugtest-server/README.md

Use this command to perform the initial installation of the application on Kubernetes. Ensure that 'docker' and 'kubectl' are installed and configured.

```sh
service/deploy_k8s.sh install
```

--------------------------------

### DemoServer Example: External Network Only

Source: https://github.com/eclipse-californium/californium/blob/main/demo-apps/cf-cloud-demo-server/README.md

Starts the DemoServer listening only on external network interfaces, disabling loopback.

```sh
DemoServer --no-loopback --device-file devices.txt
```

--------------------------------

### Start Benchmark Server

Source: https://github.com/eclipse-californium/californium/blob/main/demo-apps/cf-extplugtest-server/README.md

Command to start the benchmark server with specific JVM options for heap management and disabling plugtest.

```sh
java -Xmx6g -XX:+UseG1GC -jar cf-extplugtest-server-<version>.jar --benchmark --no-plugtest
```

--------------------------------

### Basic HTTP Forwarding Proxy2 Example

Source: https://github.com/eclipse-californium/californium/blob/main/californium-proxy2/README.md

This example demonstrates the core components and setup for an HTTP forwarding proxy. It involves initializing a client endpoint, creating a proxy HTTP server, and configuring message deliverers for CoAP request translation and forwarding.

```java
AddressEndpointContext proxy = new AddressEndpointContext(new InetSocketAddress("127.0.0.1", PROXY_PORT));
request.setDestinationContext(proxy);
// not recommended! literal IP, same as proxy
request.setURI("coap://127.0.0.1/coap-target");
request.getOptions().setUriHost("127.0.0.1");
```

```java
AddressEndpointContext proxy = new AddressEndpointContext(new InetSocketAddress("127.0.0.1", PROXY_PORT));
request.setDestinationContext(proxy);
// recommended!
request.setURI("coap://localhost/coap-target");
```

--------------------------------

### Proxy URI and Scheme Examples

Source: https://github.com/eclipse-californium/californium/blob/main/demo-apps/cf-proxy2/README.md

Illustrates different ways to specify proxy URIs and schemes for GET requests, including successful proxying and error cases.

```sh
Proxy-URI GET: http://localhost:8000/http-target
etag: 'cb3291e7', 0x6362333239316537
2.05/CONTENT --- Hi! I am the Http Server on port 8000. Request 1.
Proxy-URI GET: coap://localhost:5685/coap-target
etag: 0x4D4B9060
2.05/CONTENT --- Hi! I am the coap server on port 5685. Request 1.
Proxy-Scheme GET: http: coap://localhost:8000/http-target
etag: 'cb329206', 0x6362333239323036
2.05/CONTENT --- Hi! I am the Http Server on port 8000. Request 2.
Proxy GET: coap://localhost:5685/coap-target
etag: 0x4D4B9060
2.05/CONTENT --- Hi! I am the coap server on port 5685. Request 1.
Proxy GET: coap://127.0.0.1:5685/coap-target
etag: 0x4D4B907F
2.05/CONTENT --- Hi! I am the coap server on port 5685. Request 2.
Proxy GET: coap://127.0.0.1:5685/coap-target
etag: 0x4D4B907F
2.05/CONTENT --- Hi! I am the coap server on port 5685. Request 2.
Proxy-URI GET: http://user@localhost:8000/http-target => 4.00/BAD_REQUEST
   => 'Request URI authority contains deprecated userinfo component'
4.00/BAD_REQUEST --- Request URI authority contains deprecated userinfo component
Proxy GET: coap://localhost/coap-target => 4.04/NOT_FOUND
4.04/NOT_FOUND
```

--------------------------------

### Cloud-Init Configuration for Californium Installation

Source: https://github.com/eclipse-californium/californium/wiki/Californium-as-old-style-unix-systemd-service

This cloud-init configuration automates the installation of Californium, including package upgrades, Java runtime, fail2ban, systemd service setup, and downloading the Californium server JAR and configuration files.

```yaml
package_upgrade: true

packages:
 - openjdk-17-jre-headless
 - fail2ban

disable_root: false

users:
 - name: cali
   gecos: (Cf) Californium Server
   lock_passwd: true
   no_user_group: true

runcmd:
 - [ wget, "https://github.com/eclipse/californium/raw/main/demo-apps/cf-unix-setup/scripts/cali.service", -O, "/etc/systemd/system/cali.service" ]
 - [ wget, "https://repo.eclipse.org/content/repositories/californium-releases/org/eclipse/californium/cf-plugtest-server/4.0.0-M2/cf-plugtest-server-4.0.0-M2.jar", -O, "/home/cali/cf-plugtest-server-update.jar" ]
 - [ wget, "https://github.com/eclipse/californium/raw/main/demo-apps/cf-unix-setup/scripts/logback.xml", -O, "/home/cali/logback.xml" ]
 - [ systemctl, start, cali ]
 - [ systemctl, enable, cali ]
 - [ wget, "https://github.com/eclipse/californium/raw/main/demo-apps/cf-unix-setup/scripts/fail2ban/cali2fail.conf", -O, "/etc/fail2ban/jail.d/cali2fail.conf" ]
 - [ wget, "https://github.com/eclipse/californium/raw/main/demo-apps/cf-unix-setup/scripts/fail2ban/cali.conf", -O, "/etc/fail2ban/filter.d/cali.conf" ]
 - [ systemctl, restart, fail2ban ]


```

--------------------------------

### Get MyContext Resource (Plain CoAP)

Source: https://github.com/eclipse-californium/californium/blob/main/README.md

Example of retrieving the 'mycontext' resource using a plain CoAP GET request. This shows basic client information like IP and port.

```bash
> coap-client -p 15683 -m GET coap://californium.eclipseprojects.io/mycontext

ip: 2a02:????:915b
port: 15683
server: Cf 4.0.0-M6
```

--------------------------------

### Start ExampleSecureProxy2CoapClient

Source: https://github.com/eclipse-californium/californium/blob/main/demo-apps/cf-proxy2/README.md

Launches an example secure CoAP client (COAPS) on the same host as the proxy. This client interacts with the secure COAPS endpoint of the proxy.

```shell
java -jar cf-proxy2-<version>.jar ExampleSecureProxy2CoapClient
```

--------------------------------

### Client GET Request to a Simple Server (UDP)

Source: https://github.com/eclipse-californium/californium/blob/main/californium-core/README.md

Example of a CoapClient making a GET request to a simple CoapServer. Assumes the server is running and accessible.

```java
CoapConfig.register();
UdpConfig.register();

CoapClient client = new CoapClient("coap://<your-host-name>");
Response response = client.get();
...
client.shutdown();
```

--------------------------------

### Install OpenJDK on Ubuntu

Source: https://github.com/eclipse-californium/californium/wiki/Californium---running-the-sandbox-locally-for-integration-tests

Install the headless Java Development Kit (OpenJDK) version 17 on Ubuntu systems using apt.

```bash
sudo apt install openjdk-17-jre-headless
```

--------------------------------

### Domain Configuration File Example

Source: https://github.com/eclipse-californium/californium/blob/main/demo-apps/cf-s3-proxy-server/README.md

This example shows the structure of a domains.txt file, defining configurations for 'domain1' and 'domain2', including S3 bucket details, access keys, and management file paths.

```text
[web]
domain = domain1

[domain1.data]

host_base = sos-de-fra-1.exo.io
host_bucket = %(bucket)s.sos-de-fra-1.exo.io
bucket = devices1
access_key = <S3-access-key-id1>
secret_key = <S3-access-key-secret1>
compress = true

[domain1.management]

host_base = sos-de-fra-1.exo.io
host_bucket = %(bucket)s.sos-de-fra-1.exo.io
bucket = devices1mgmt
access_key = <S3-access-key-id2>
secret_key = <S3-access-key-secret2>

device_store = devices.txt
config_store = configs.txt
user_store = users.txt

[domain2.data]

host_base = sos-de-fra-1.exo.io
host_bucket = %(bucket)s.sos-de-fra-1.exo.io
bucket = devices2
access_key = <S3-access-key-id3>
secret_key = <S3-access-key-secret3>
compress = true

[domain2.management]

host_base = sos-de-fra-1.exo.io
host_bucket = %(bucket)s.sos-de-fra-1.exo.io
bucket = devices2mgmt
access_key = <S3-access-key-id4>
secret_key = <S3-access-key-secret4>

device_store = devices.txt
config_store = configs.txt
user_store = users.txt

```

--------------------------------

### Benchmark Client and Server Interaction Example

Source: https://github.com/eclipse-californium/californium/blob/main/demo-apps/cf-extplugtest-server/README.md

Example output showing the creation of benchmark clients, sending requests, and receiving responses, including DTLS handshake details and performance metrics.

```text
Create 2000 none-stop secure benchmark clients, expect to send 1000000000 requests overall to coaps://????:5784/benchmark?rlen=40
Use PSK.
11:18:56.200: Request:
==[ CoAP Request ]=============================================
MID    : 39238
Token  : CCD3FF946AE68279
Type   : CON
Method : 0.02 - POST
Options: {"Uri-Host":"???", "Uri-Path":"benchmark", "Content-Format":"text/plain", "Uri-Query":"rlen=40", "Accept":"text/plain"}
Payload: 0 Bytes
===============================================================
11:18:56.216: >>> CONNECTING <<<
11:18:56.497: >>> DTLS(????:??,ID:2FB1132D5E)
>>> TLS_PSK_WITH_AES_128_CCM_8
>>> PreSharedKey Identity [identity: cali.A2F2E01AC4C5C52E]
>>> read-cid : 
>>> write-cid: 89B3BE674AA2
11:18:56.509: Received response:
==[ CoAP Response ]============================================
MID    : 39238
Token  : CCD3FF946AE68279
Type   : ACK
Status : 2.04 - CHANGED
Options: {"Content-Format":"text/plain"}
RTT    : 316 ms
Payload: 40 Bytes
---------------------------------------------------------------
hello benchmark*************************
===============================================================
Benchmark clients, first request successful.
Benchmark clients created. 668 ms, 2993 clients/s
11:18:57.499: register shutdown hook.
Benchmark started.
286184 requests (28618 reqs/s, 5005 retransmissions (1,72%), 0 transmission errors (0,00%), 2000 clients)
601072 requests (31489 reqs/s, 6575 retransmissions (2,09%), 0 transmission errors (0,00%), 2000 clients)
945326 requests (34425 reqs/s, 6687 retransmissions (1,94%), 0 transmission errors (0,00%), 2000 clients)
1296353 requests (35103 reqs/s, 6652 retransmissions (1,89%), 0 transmission errors (0,00%), 2000 clients)
1643276 requests (34692 reqs/s, 6716 retransmissions (1,94%), 0 transmission errors (0,00%), 2000 clients)
1991747 requests (34847 reqs/s, 6770 retransmissions (1,94%), 0 transmission errors (0,00%), 2000 clients)
2337099 requests (34535 reqs/s, 6711 retransmissions (1,94%), 0 transmission errors (0,00%), 2000 clients)
2678691 requests (34159 reqs/s, 6704 retransmissions (1,96%), 0 transmission errors (0,00%), 2000 clients)
3025392 requests (34670 reqs/s, 6726 retransmissions (1,94%), 0 transmission errors (0,00%), 2000 clients)
3367248 requests (34186 reqs/s, 6768 retransmissions (1,98%), 0 transmission errors (0,00%), 2000 clients)
...
```

--------------------------------

### Get MyContext Resource (CoAPS with PSK)

Source: https://github.com/eclipse-californium/californium/blob/main/README.md

Example of retrieving the 'mycontext' resource using CoAPS with a Pre-Shared Key (PSK). This demonstrates secure communication and provides more detailed client and session information.

```bash
> coap-client -p 15684 -m GET -u Client_identity -k secretPSK coaps://californium.eclipseprojects.io/mycontext

ip: 2a02:????:915b
port: 15684
peer: Client_identity
cipher-suite: TLS_PSK_WITH_AES_128_CCM_8
session-id: 3BBC6EBAAA4F4A4717EEC8FF2C3FB1CFC4C9C89E9807EB0F1C0CDC11C6D9110C
read-cid: 1CF2CC41B37E
write-cid: 
secure-renegotiation: true
ext-master-secret: true
newest-record: true
message-size-limit: 1343
server: Cf 4.0.0-M6
```

--------------------------------

### Start a Simple CoapServer (UDP)

Source: https://github.com/eclipse-californium/californium/blob/main/californium-core/README.md

Shows how to start a basic CoapServer listening on the default CoAP port (5683) for UDP transport. Ensure CoapConfig and UdpConfig are registered.

```java
CoapConfig.register();
UdpConfig.register();

CoapServer server = new CoapServer();
server.start()
...
server.destroy();
```

--------------------------------

### Start Node 2 (Static Mode)

Source: https://github.com/eclipse-californium/californium/blob/main/demo-apps/cf-extplugtest-server/README.md

Starts node 2 with a static cluster configuration, specifying its own and another node's cluster management interface.

```sh
java -jar target/cf-extplugtest-server-<version>.jar --dtls-cluster "---;localhost:15884;1,:25784;localhost:25884;2"
```

--------------------------------

### Start Node 1 (Static Mode)

Source: https://github.com/eclipse-californium/californium/blob/main/demo-apps/cf-extplugtest-server/README.md

Starts node 1 with a static cluster configuration, specifying its own and another node's cluster management interface.

```sh
java -jar target/cf-extplugtest-server-<version>.jar --dtls-cluster ":15784;localhost:15884;1,---;localhost:25884;2"
```

--------------------------------

### cf-nat Console Output Example

Source: https://github.com/eclipse-californium/californium/blob/main/demo-apps/cf-extplugtest-server/README.md

Example console output from the cf-nat load balancer indicating that reverse address update is enabled and showing the current destination entries.

```text
0 NAT entries, reverse address update enabled.
2 destinations.
Destination: <host>:15784, usage: 0
Destination: <host>:25784, usage: 0
```

--------------------------------

### Starting Californium Java Process in Container

Source: https://github.com/eclipse-californium/californium/wiki/Californium-as-k8s-service

Configures the entry point for the container, starting the Californium server JAR with specific JVM flags and command-line arguments for Kubernetes integration.

```dockerfile
WORKDIR /opt/app
CMD ["java", "-XX:+UseContainerSupport", "-XX:MaxRAMPercentage=75", "-jar", "./cf-extplugtest-server.jar", "--no-plugtest", "--no-tcp", "--benchmark", "--k8s-dtls-cluster", ":5784;:5884;5884", "--k8s-monitor", ":8080", "--k8s-restore", ":5884"]
```

--------------------------------

### Cloud-Init Configuration for Californium

Source: https://github.com/eclipse-californium/californium/blob/main/demo-apps/cf-unix-setup/README.md

This cloud-init configuration installs necessary packages, sets up the Californium service, and configures fail2ban. It's designed for automatic installation on cloud VMs.

```yaml
package_upgrade: true

packages:
 - openjdk-17-jre-headless
 - fail2ban

disable_root: false

users:
 - name: cali
   gecos: (Cf) Californium Server
   lock_passwd: true
   no_user_group: true

runcmd:
 - [ wget, "https://github.com/eclipse-californium/californium/raw/main/demo-apps/cf-unix-setup/scripts/cali.service", -O, "/etc/systemd/system/cali.service" ]
 - [ wget, "https://repo.eclipse.org/content/repositories/californium-releases/org/eclipse/californium/cf-plugtest-server/4.0.0-M6/cf-plugtest-server-4.0.0-M6.jar", -O, "/home/cali/cf-plugtest-server-update.jar" ]
 - [ wget, "https://github.com/eclipse-californium/californium/raw/main/demo-apps/cf-unix-setup/scripts/logback.xml", -O, "/home/cali/logback.xml" ]
 - [ systemctl, start, cali ]
 - [ systemctl, enable, cali ]
 - [ wget, "https://github.com/eclipse-californium/californium/raw/main/demo-apps/cf-unix-setup/scripts/fail2ban/cali2fail.conf", -O, "/etc/fail2ban/jail.d/cali2fail.conf" ]
 - [ wget, "https://github.com/eclipse-californium/californium/raw/main/demo-apps/cf-unix-setup/scripts/fail2ban/cali.conf", -O, "/etc/fail2ban/filter.d/cali.conf" ]
 - [ sleep, 5 ]
 - [ systemctl, restart, fail2ban ]

```

--------------------------------

### Specialized Reverse Proxy - Get Destination URI

Source: https://github.com/eclipse-californium/californium/blob/main/californium-proxy2/README.md

Example of how to get the destination URI for a request in a specialized reverse proxy implementation.

```java
URI destination = translator.getDestinationURI(incomingRequest, exposedInterface);
```

--------------------------------

### Cloud Demo Server Command Line Help

Source: https://github.com/eclipse-californium/californium/blob/main/demo-apps/cf-cloud-demo-server/README.md

Displays the available command-line options and arguments for starting the Cloud Demo Server.

```sh
java -jar cf-cloud-demo-server-<version>.jar -h

Usage: CloudDemoServer [-h] [--diagnose] [--wildcard-interface | [[--[no-]
                       loopback] [--[no-]external] [--[no-]ipv4] [--[no-]ipv6]
                       [--interfaces-pattern=<interfacePatterns>[,
                       <interfacePatterns>...]]...]]
                       [--coaps-credentials=<credentials>
                       [--coaps-password64=<password64>]] [--device-file=<file>
                       [--device-file-password64=<password64>]]
                       [--store-file=<file> --store-max-age=<maxAge>
                       [--store-password64=<password64>]] [--provisioning
                       [--replace]] [[--https-port=<port>]
                       --https-credentials=<credentials>
                       [--https-password64=<password64>]]
      --coaps-credentials=<credentials>
                             Folder containing coaps credentials in 'privkey.
                               pem' and 'pubkey.pem'
      --coaps-password64=<password64>
                             Password for device store. Base 64 encoded.
      --device-file=<file>   Filename of device store for coap.
      --device-file-password64=<password64>
                             Password for device store. Base 64 encoded.
      --diagnose             enable 'diagnose'-resource.
  -h, --help                 display a help message
      --https-credentials=<credentials>
                             Folder containing https credentials in 'privkey.
                               pem' and 'fullchain.pem'.
      --https-password64=<password64>
                             Password for https credentials. Base 64 encoded.
      --https-port=<port>    Port of https service. Default: 8080
      --interfaces-pattern=<interfacePatterns>[,<interfacePatterns>...]
                             interface regex patterns for coap endpoints.
      --[no-]external        enable coap endpoints on external network.
      --[no-]ipv4            enable coap endpoints for ipv4.
      --[no-]ipv6            enable coap endpoints for ipv6.
      --[no-]loopback        enable coap endpoints on loopback network.
      --provisioning         enable 'prov'-resource for auto-provisioning.
      --replace              replaces previous device credentials entries with
                               new entries. For use during development. Don't
                               use it for production!
      --store-file=<file>    file-store for dtls state.
      --store-max-age=<maxAge>
                             maximum age of connections in hours to store dtls
                               state.
      --store-password64=<password64>
                             password to store dtls state. Base 64 encoded.
      --wildcard-interface   Use local wildcard-address for coap endpoints.
                               Default mode.

```

--------------------------------

### Send GET Request using CoapClient (DTLS)

Source: https://github.com/eclipse-californium/californium/blob/main/californium-core/README.md

Demonstrates sending a CoAP GET request over DTLS using CoapClient. Requires DTLS endpoint setup and registration with EndpointManager.

```java
CoapConfig.register();
DtlsConfig.register();

// some DTLS endpoint setup as above

CoapEndpoint endpoint = CoapEndpoint.builder()
   .setConnector(new DTLSConnector(dtlsConfiguration))
   .build();

EndpointManager.getEndpointManager().setDefaultEndpoint(endpoint);

CoapClient client = new CoapClient("coaps://californium.eclipseprojects.io/test");
Response response = client.get();
...
client.shutdown();
```

--------------------------------

### Deploy Cloud Demo Server with ExoScale

Source: https://github.com/eclipse-californium/californium/blob/main/demo-apps/cf-cloud-demo-server/README.md

This command creates an ExoScale cloud VM, installs the cloud-demo-server, generates RPK keys, adjusts file permissions, and reboots the VM. It sets up initial PSK credentials that should be replaced.

```sh
./deploy-dev.sh exo create install
```

--------------------------------

### DemoServer Example: Device Credentials and DTLS Graceful Restart

Source: https://github.com/eclipse-californium/californium/blob/main/demo-apps/cf-cloud-demo-server/README.md

Configures the DemoServer with device credentials from a file and enables DTLS graceful restart. Skips devices/sessions with no exchange for over a week when saving.

```sh
DemoServer --store-file dtls.bin --store-max-age 168 \
                --store-password64 ZVhiRW5pdkx1RUs2dmVoZg== \
                --device-file devices.txt
```

--------------------------------

### Client GET Requests with Mapped Paths

Source: https://github.com/eclipse-californium/californium/blob/main/demo-apps/cf-simplefile-server/README.md

Examples of client GET requests to retrieve files using the mapped CoAP URIs. These requests target specific files within the server's configured path root.

```sh
java -jar cf-helloworld-client-<version>.jar GETClient coap://localhost/files/cf_64.png picture2save.png
java -jar cf-helloworld-client-<version>.jar GETClient coap://localhost/files/fw/device.hex firmware.hex
```

--------------------------------

### Device Credentials after Provisioning

Source: https://github.com/eclipse-californium/californium/blob/main/demo-apps/cf-cloud-demo-server/README.md

Example of device credentials after successful provisioning, including the device ID, RPK, and signature.

```text
... 
# added 2024-08-11T07:00:19Z by Provisioning1
device-id=Thing
.rpk=MFkwEwYHKoZIzj0CAQYIKoZIzj0DAQcDQgAEe7jf4/mFVId9GnUfFdV1XQVUAn4fAKsctXYfLnrcvKMXAPAKe6mLPNMNxXf/+TsDQDXEcamWAcjDUFVc/9pIeQ==
.sig=BAMARzBFAiEAkL9amzTcqBrovw3EPeUJ+iB/NhiEhgS603VBGDx6UUMCIDNfKVwOG7aCQVnsL7mDqgQZhXW7XrCMEKp0hAk7wGac
```

--------------------------------

### Device Provisioning with RPK

Source: https://github.com/eclipse-californium/californium/blob/main/demo-apps/cf-cloud-demo-server/README.md

Example of device provisioning using RPK credentials. This entry includes a name, the public key, and the type set to 'prov'.

```text
Provisioning1=Admin
.rpk=MFkwEwYHKoZIzj0CAQYIKoZIzj0DAQcDQgAENTGXGkhc7gL614R4HBOkXoESM98YIXP3yts4VG7wpRlsIxYFFXVez3I3VE7oGaOpLlAMMhFa4Myq/4OIRMvauQ==
.type=prov
```

--------------------------------

### Example: Forward traffic to multiple destinations

Source: https://github.com/eclipse-californium/californium/blob/main/cf-utils/cf-nat/README.md

Starts a (s)NAT listening on UDP port 5684 on any interface, forwarding traffic to three specified DTLS receivers. Assumes the destinations offer the service on the given ports.

```sh
java -jar cf-nat-<version>.jar :5684 node1.coap.cluster:5684 node2.coap.cluster:5684 node2.coap.cluster:5784
```

--------------------------------

### Retrieve Firmware from S3

Source: https://github.com/eclipse-californium/californium/blob/main/demo-apps/cf-s3-proxy-server/README.md

Use coap-client to GET firmware from the S3 proxy server. This example shows how to retrieve firmware for a specific device type and version using RFC 7959 (CoAP blockwise transfer).

```sh
coap-client -v 6 -m GET -u Client_identity -k secretPSK coaps://${s3proxy}/fw/box/0.11.107+0
```

--------------------------------

### Device Store Configuration Example

Source: https://github.com/eclipse-californium/californium/blob/main/demo-apps/cf-s3-proxy-server/README.md

Defines a device entry for the Cloud Demo Server, including its label, PSK credentials, RPK certificate, forwarding destination, authentication, and response patterns. This format is used for device management.

```properties
Demo.10034780012=Thing
.label=My Demo Weatherstation
# default openssl PSK credentials
.psk='Client_identity',c2VjcmV0UFNL
# Californium demo-client RPK certificate
.rpk=MFkwEwYHKoZIzj0CAQYIKoZIzj0DAQcDQgAEQxYO5/M5ie6+3QPOaAy5MD6CkFILZwIb2rOBCX/EWPaocX1H+eynUnaEEbmqxeN6rnI/pH19j4PtsegfHLrzzQ==
.fdest=https://api.tago.io/data
.fauth=Header device-token: ????????-????-????-????-????????????
.fresp=.*"status":\s*true,.*
```

--------------------------------

### Install Fail2ban

Source: https://github.com/eclipse-californium/californium/wiki/Californium-as-old-style-unix-systemd-service

Installs the Fail2ban service on Debian-based systems.

```bash
sudo apt install fail2ban
```

--------------------------------

### Build and Tag Docker Image in One Step

Source: https://github.com/eclipse-californium/californium/wiki/Californium-as-k8s-service

Builds a Docker image from a Dockerfile and tags it for a cloud registry simultaneously. Specify the correct path to your Dockerfile.

```bash
> docker build . -t <cloud-registry>/cf-extserver-jdk11-slim -f service/Dockerfile
```

--------------------------------

### Install OpenJDK 11 JRE (Ubuntu 18.04)

Source: https://github.com/eclipse-californium/californium/wiki/Californium-as-old-style-unix-systemd-service

Installs the OpenJDK 11 JRE with headless support on Ubuntu 18.04 LTS. This is an alternative Java installation for Californium.

```bash
sudo apt install openjdk-11-jre-headless
```

--------------------------------

### Start Californium Service

Source: https://github.com/eclipse-californium/californium/wiki/Californium-as-old-style-unix-systemd-service

Use this command to start the Californium systemd service.

```bash
sudo systemctl start cali
```

--------------------------------

### Run Californium Plugtest Server

Source: https://github.com/eclipse-californium/californium/wiki/Californium---running-the-sandbox-locally-for-integration-tests

Start the Californium plugtest server by executing its JAR file from the command line in the directory where it was downloaded.

```bash
java -jar cf-plugtest-server-4.0.0-M2.jar
```

--------------------------------

### Initialize PubSub Client

Source: https://github.com/eclipse-californium/californium/blob/main/cf-pubsub/README.md

Instantiate the PubSub client with the broker's address and optional port and timeout.

```java
PubSub pubsub = new PubSub("127.0.0.1"); 
OR
PubSub pubsub = new PubSub("127.0.0.1", 5683, 5000);
```

--------------------------------

### PEM Private Key Example

Source: https://github.com/eclipse-californium/californium/blob/main/element-connector/README.md

Example of a PEM-encoded EC private key. This format is base64 encoded with descriptive comments.

```text
-----BEGIN EC PRIVATE KEY-----
MHcCAQEEIBw7lyMR21FDpCecT0bNr4oKBuYw1VdNnCB5xSS4dQrcoAoGCCqGSM49
AwEHoUQDQgAETY8Y02TZuaRUQvXnguxg6EPN7wR5vzxthmDk+6vvf6oJgBylWIU2
E3khCBkZM9Um7JCA9/kcbNezwJDzyQAnIw==
-----END EC PRIVATE KEY-----
```

--------------------------------

### S3ProxyServer Basic Configuration

Source: https://github.com/eclipse-californium/californium/blob/main/demo-apps/cf-s3-proxy-server/README.md

Launches the S3ProxyServer with specified S3 configuration, DTLS state storage, and device/user files. This is a common setup for persistent device and user management.

```bash
S3ProxyServer --store-file dtls.bin --store-max-age 168 \
                --store-password64 ZVhiRW5pdkx1RUs2dmVoZg== \
                --device-file devices.txt --user-file users.txt \
                --s3-config ~/.s3cfg
```

--------------------------------

### CoAP GET and PUT Requests

Source: https://github.com/eclipse-californium/californium/blob/main/demo-apps/cf-proxy2/README.md

Shows a CoAP GET request with detailed response information and PUT requests with and without payload.

```sh
=== GET http://californium.eclipseprojects.io:5683/test/coap: ===
HTTP/1.1 200 OK
Cache-Control: max-age=30
content-type: text/plain; charset=ISO-8859-1
Date: So., 20 Okt. 2024 15:20:27 GMT
Content-Length: 61
Type: 0 (CON)
Code: 1 (GET)
MID: 1658
Token: F08EF92E7C93E122
=== PUT http://californium.eclipseprojects.io:5683/test/coap: === (no payload)
HTTP/1.1 204 No Content
Date: So., 20 Okt. 2024 15:20:27 GMT
<empty>
=== PUT http://californium.eclipseprojects.io:5683/test/coap: === ''
HTTP/1.1 204 No Content
Date: So., 20 Okt. 2024 15:20:27 GMT
<empty>
=== PUT http://californium.eclipseprojects.io:5683/test/coap: === '1234'
HTTP/1.1 204 No Content
Date: So., 20 Okt. 2024 15:20:27 GMT
<empty>
```

--------------------------------

### Run Simple File Server

Source: https://github.com/eclipse-californium/californium/blob/main/demo-apps/cf-simplefile-server/README.md

Start the Simple File Server JAR. Optionally specify the file root directory and the CoAP root path for accessing files.

```sh
java -jar cf-simplefile-server-<version>.jar [--file-root=<file-root-directory>] [--path-root=<coap-root>]
```

--------------------------------

### Deploy Cloud CoAP-S3-Proxy Server with ExoScale

Source: https://github.com/eclipse-californium/californium/blob/main/demo-apps/cf-s3-proxy-server/README.md

This command creates an ExoScale cloud VM, installs the Cloud CoAP-S3-Proxy server, and configures it. It sets up initial PSK credentials that should be replaced.

```sh
./deploy-dev.sh <domain> exo create create-bucket install
```

--------------------------------

### Install OpenJDK 8 JRE (Ubuntu 18.04)

Source: https://github.com/eclipse-californium/californium/wiki/Californium-as-old-style-unix-systemd-service

Installs the OpenJDK 8 JRE with headless support on Ubuntu 18.04 LTS. This is a prerequisite for running Californium.

```bash
sudo apt install openjdk-8-jre-headless
```

--------------------------------

### Start Node 3 (Dynamic Mode)

Source: https://github.com/eclipse-californium/californium/blob/main/demo-apps/cf-extplugtest-server/README.md

Starts node 3 in dynamic cluster mode, specifying its own cluster management interface and a group of interfaces for other nodes.

```sh
java -jar target/cf-extplugtest-server-<version>.jar --dtls-cluster ":35784;localhost:35884;3" --dtls-cluster-group="localhost:15884,localhost:25884"
```

--------------------------------

### Run Server with Custom Logback Configuration

Source: https://github.com/eclipse-californium/californium/wiki/Californium---running-the-sandbox-locally-for-integration-tests

Start the Californium plugtest server using a custom logback.xml file to control logging output. This command specifies the logback configuration file to use.

```bash
java -Dlogback.configurationFile=./logback.xml -jar cf-plugtest-server-4.0.0-M2.jar
```

--------------------------------

### Start Node 2 (Dynamic Mode)

Source: https://github.com/eclipse-californium/californium/blob/main/demo-apps/cf-extplugtest-server/README.md

Starts node 2 in dynamic cluster mode, specifying its own cluster management interface and a group of interfaces for other nodes.

```sh
java -jar target/cf-extplugtest-server-<version>.jar --dtls-cluster ":25784;localhost:25884;2" --dtls-cluster-group="localhost:15884,localhost:35884"
```

--------------------------------

### Example C-Header Content

Source: https://github.com/eclipse-californium/californium/blob/main/cf-utils/cf-encrypt/README.md

Illustrates the content of a generated C-header file for a private key, showing the BEGIN/END markers and base64 encoded data.

```c
"-----BEGIN PRIVATE KEY-----\n"
"MEEC.........................................................Clu\n"
"VT4l.....................w==\n"
"-----END PRIVATE KEY-----\n"
```

--------------------------------

### Start Node 1 (Dynamic Mode)

Source: https://github.com/eclipse-californium/californium/blob/main/demo-apps/cf-extplugtest-server/README.md

Starts node 1 in dynamic cluster mode, specifying its own cluster management interface and a group of interfaces for other nodes.

```sh
java -jar target/cf-extplugtest-server-<version>.jar --dtls-cluster ":15784;localhost:15884;1" --dtls-cluster-group="localhost:25884,localhost:35884"
```

--------------------------------

### File System Mapping Example

Source: https://github.com/eclipse-californium/californium/blob/main/demo-apps/cf-simplefile-server/README.md

Demonstrates how to map a file system structure to CoAP URIs using --file-root and --path-root options. Files in the specified file system tree are accessed via the CoAP path root.

```sh
java -jar cf-simplefile-server-<version>.jar --file-root=/home/cali/data --path-root=files --no-tcp
```