Creates a layered configuration for lbrycrd start.sh

lbrycrd/README.md

@@ -2,3 +2,47 @@
 # Docker image tags
 `lbry/lbrycrd`
 `[linux-x86_64-production](https://github.com/lbryio/lbry-docker/blob/master/lbrycrd/Dockerfile-linux-x86_64-production)` (Latest release)
+
+
+## Configuration
+
+The lbrycrd container comes with a default configuration you can use for
+production. Extra configuration is optional.
+
+The container includes a `start` script that offers a flexible configuration
+style. It allows you to mount your own `lbrycrd.conf` file, or use environment
+variables, or a mix of both.
+
+### Environment variables
+
+The environment variables override the values in the mounted config file. If no
+mounted config file exists, these variables are used to create a fresh config.
+
+ * `PORT` - The main lbrycrd port
+ * `RPC_USER` - The rpc user
+ * `RPC_PASSWORD` - The rpc user's password
+ * `RPC_ALLOW_IP` - the subnet that is allowed rpc access
+ * `RPC_PORT` - The port to bind the rpc service to
+ * `RPC_BIND` - The ip address to bind the rpc service to
+ 
+
+### Example run commands
+
+Running the default configuration:
+
+```
+docker run --rm -it -e RUN_MODE=default lbry/lbrycrd:linux-x86_64-production
+```
+
+Running with RPC password changed:
+
+```
+docker run --rm -it -e RUN_MODE=default -e RPC_PASSWORD=hunter2 lbry/lbrycrd:linux-x86_64-production
+```
+
+Running with a config file but with the RPC password still overridden:
+
+```
+docker run --rm -it -v /path/to/lbrycrd.conf:/etc/lbry/lbrycrd.conf -e RUN_MODE=default -e RPC_PASSWORD=hunter2 lbry/lbrycrd:linux-x86_64-production
+```
+

lbrycrd/stuff/start.sh

@@ -1,24 +1,54 @@
 #!/usr/bin/env bash
 CONFIG_PATH=/etc/lbry/lbrycrd.conf
 
+function override_config_option() {
+    # Remove existing config line from a config file
+    #  and replace with environment fed value.
+    # Does nothing if the variable does not exist.
+    #  var     Name of ENV variable
+    #  option  Name of config option
+    #  config  Path of config file
+    local var=$1 option=$2 config=$3
+    if [[ -v $var ]]; then
+        # Remove the existing config option:
+        sed -i "/^$option\W*=/d" $config
+        # Add the value from the environment:
+        echo "$option=${!var}" >> $config
+    fi
+}
+
 function set_config() {
-  CONFIG_PATH=/etc/lbry/lbrycrd.conf
-  if [ -f "$CONFIG_PATH" ]
-  then
-      echo "Using the config file that was mounted into the container."
+  if [ -d "$CONFIG_PATH" ]; then
+      echo "$CONFIG_PATH is a directory when it should be a file."
+      exit 1
+  elif [ -f "$CONFIG_PATH" ]; then
+      echo "Merging the mounted config file with environment variables."
+      local MERGED_CONFIG=/tmp/lbrycrd_merged.conf
+      cat $CONFIG_PATH > $MERGED_CONFIG
+      echo "" >> $MERGED_CONFIG
+      override_config_option PORT port $MERGED_CONFIG
+      override_config_option RPC_USER rpcuser $MERGED_CONFIG
+      override_config_option RPC_PASSWORD rpcpassword $MERGED_CONFIG
+      override_config_option RPC_ALLOW_IP rpcallowip $MERGED_CONFIG
+      override_config_option RPC_PORT rpcport $MERGED_CONFIG
+      override_config_option RPC_BIND rpcbind $MERGED_CONFIG
+      # Make the new merged config file the new CONFIG_PATH
+      # This ensures that the original file the user mounted remains unmodified
+      CONFIG_PATH=$MERGED_CONFIG
   else
       echo "Creating a fresh config file from environment variables."
       ## Set config params
-      echo "rpcuser=$RPC_USER" > $CONFIG_PATH
-      echo "rpcpassword=$RPC_PASSWORD" >> $CONFIG_PATH
-      echo "rpcallowip=$RPC_ALLOW_IP" >> $CONFIG_PATH
-      echo "rpcport=9245" >> $CONFIG_PATH
-      echo "rpcbind=0.0.0.0" >> $CONFIG_PATH
-      #echo "bind=0.0.0.0" >> $CONFIG_PATH
+      echo "port=${PORT=9246}" > $CONFIG_PATH
+      echo "rpcuser=${RPC_USER=lbry}" >> $CONFIG_PATH
+      echo "rpcpassword=${RPC_PASSWORD=lbry}" >> $CONFIG_PATH
+      echo "rpcallowip=${RPC_ALLOW_IP=127.0.0.1/24}" >> $CONFIG_PATH
+      echo "rpcport=${RPC_PORT=9245}" >> $CONFIG_PATH
+      echo "rpcbind=${RPC_BIND=0.0.0.0}" >> $CONFIG_PATH
   fi
+  echo "Config: "
+  cat $CONFIG_PATH
 }
 
-
 ## Ensure perms are correct prior to running main binary
 /usr/bin/fix-permissions