docker: simplify duniter subcommand run

When the first argument of the entrypoint is not an option or is '--'
then bypass the default configuration via environment variables and
directly run duniter with the given parameters (after removing the first
one when it is '--').

The affected scripts and documentation were updated.

docker/README.md

@@ -80,3 +80,24 @@ You can pass any other option to duniter using the `command` docker-compose elem
       # https://github.com/paritytech/substrate/issues/12073
       - "--wasm-execution=interpreted-i-know-what-i-do"
 ```
+
+# Running duniter subcommands
+
+You can run any duniter subcommand this way:
+```
+$ docker run --rm duniter/duniter-v2s:latest <subcommand> ...
+```
+
+For example to generate a key:
+```
+$ docker run --rm duniter/duniter-v2s:latest key generate
+```
+
+In this case the `DUNITER_*` environment variables are ignored.
+
+# Running custom duniter options
+
+To test duniter from the command line without the default configuration detailed in the "Environment variables" section use `--` as the first argument. For example:
+```
+$ docker run --rm duniter/duniter-v2s:latest -- --chain gdev ...
+```

docker/docker-entrypoint

 #!/bin/bash
 
+# Subcommand or custom startup
+# If a first argument is present
+# * and is not an option (doesn't start with '-')
+# * or is equal to '--'
+# then we just run duniter with the provided arguments (but the first '--')
+# without applying all the automated configuration below
+if [ -n "$1" -a \( "${1:0:1}" != - -o "$1" = -- \) ]; then
+  if [ "$1" = -- ]; then
+    shift
+  fi
+  exec duniter "$@"
+fi
+
+# Normal startup
 function boolean () {
   echo "$1" | sed -E 's/^(true|yes|1)$/true/i'
 }

docs/dev/launch-a-live-network.md

@@ -21,7 +21,7 @@ docker image that you have chosen.
 Generate a random secret phrase:
 
 ```bash
-$ docker run --rm -it --entrypoint duniter duniter/duniter-v2s:TAG key generate
+$ docker run --rm duniter/duniter-v2s:TAG key generate
 Secret phrase:       noble stay fury mean poverty delay stadium organ evil east vague can
   Secret seed:       0xb39c31fb10c5080721738880c2ea45412cb3df33df022bf8d9a51483b3a9b7a6
   Public key (hex):  0x90a0c2866034db9d05f8193a95fe5af8d5e12ab295a501c17c95cdbeaf226d62
@@ -35,7 +35,7 @@ Keep this secret phrase **carefully**, it will be used **several** times later.
 Then, generate the session keys:
 
 ```bash
-$ docker run --rm -it --entrypoint duniter duniter/duniter-v2s:TAG key generate-session-keys --chain CURRENCY_local --suri "<your secret phrase>"
+$ docker run --rm duniter/duniter-v2s:TAG key generate-session-keys --chain CURRENCY_local --suri "<your secret phrase>"
 Session Keys: 0x87189d723e1b2826c243bc433c718ac26ba60526932216a09102a254d54462b890a0c2866034db9d05f8193a95fe5af8d5e12ab295a501c17c95cdbeaf226d6290a0c2866034db9d05f8193a95fe5af8d5e12ab295a501c17c95cdbeaf226d6290a0c2866034db9d05f8193a95fe5af8d5e12ab295a501c17c95cdbeaf226d62
 ```
 
@@ -46,7 +46,7 @@ An example of genesis configuration file: `resources/gdev.json`
 ## 5. Generate raw spec
 
 ```docker
-docker run -v $HOME/dev/duniter-v2s/resources:/var/lib/duniter/resources -e DUNITER_GENESIS_CONFIG=/var/lib/duniter/resources/gdev.json --rm -it --entrypoint duniter duniter/duniter-v2s:TAG build-spec -lerror --chain=gdev-gl --raw > name-raw.json
+docker run -v $HOME/dev/duniter-v2s/resources:/var/lib/duniter/resources -e DUNITER_GENESIS_CONFIG=/var/lib/duniter/resources/gdev.json --rm duniter/duniter-v2s:TAG build-spec -lerror --chain=gdev-gl --raw > name-raw.json
 ```
 
 ```bash

scripts/create-live-network.sh

@@ -31,8 +31,7 @@ mkdir -p $WORK_DIR/duniter-validator/chains/$CURRENCY
 
 # Helper to execute a duniter subcommand in docker
 function duniter_tmp () {
-  docker rm duniter-tmp > /dev/null
-  OUTPUT=$(docker run --name duniter-tmp -it --entrypoint duniter duniter/duniter-v2s:$DUNITER_IMAGE_TAG "$@")
+  OUTPUT=$(docker run --rm --name duniter-tmp duniter/duniter-v2s:$DUNITER_IMAGE_TAG "$@")
   echo "${OUTPUT::-1}"
 }