docs: networks/docker-compose: small fixes (#3017)

Makefile

@@ -294,6 +294,7 @@ build-linux:
 build-docker-localnode:
 	cd networks/local
 	make
+	cd -
 
 # Run a 4-node testnet locally
 localnet-start: localnet-stop

docs/networks/docker-compose.md

@@ -1,20 +1,17 @@
 # Docker Compose
 
-With Docker Compose, we can spin up local testnets in a single command:
-
-```
-make localnet-start
-```
+With Docker Compose, you can spin up local testnets with a single command.
 
 ## Requirements
 
-- [Install tendermint](/docs/install.md)
-- [Install docker](https://docs.docker.com/engine/installation/)
-- [Install docker-compose](https://docs.docker.com/compose/install/)
+1. [Install tendermint](/docs/install.md)
+2. [Install docker](https://docs.docker.com/engine/installation/)
+3. [Install docker-compose](https://docs.docker.com/compose/install/)
 
 ## Build
 
-Build the `tendermint` binary and the `tendermint/localnode` docker image.
+Build the `tendermint` binary and, optionally, the `tendermint/localnode`
+docker image.
 
 Note the binary will be mounted into the container so it can be updated without
 rebuilding the image.
@@ -25,11 +22,10 @@ cd $GOPATH/src/github.com/tendermint/tendermint
 # Build the linux binary in ./build
 make build-linux
 
-# Build tendermint/localnode image
+# (optionally) Build tendermint/localnode image
 make build-docker-localnode
 ```
 
-
 ## Run a testnet
 
 To start a 4 node testnet run:
@@ -38,9 +34,13 @@ To start a 4 node testnet run:
 make localnet-start
 ```
 
-The nodes bind their RPC servers to ports 26657, 26660, 26662, and 26664 on the host.
+The nodes bind their RPC servers to ports 26657, 26660, 26662, and 26664 on the
+host.
+
 This file creates a 4-node network using the localnode image.
-The nodes of the network expose their P2P and RPC endpoints to the host machine on ports 26656-26657, 26659-26660, 26661-26662, and 26663-26664 respectively.
+
+The nodes of the network expose their P2P and RPC endpoints to the host machine
+on ports 26656-26657, 26659-26660, 26661-26662, and 26663-26664 respectively.
 
 To update the binary, just rebuild it and restart the nodes:
 
@@ -52,34 +52,40 @@ make localnet-start
 
 ## Configuration
 
-The `make localnet-start` creates files for a 4-node testnet in `./build` by calling the `tendermint testnet` command.
+The `make localnet-start` creates files for a 4-node testnet in `./build` by
+calling the `tendermint testnet` command.
 
-The `./build` directory is mounted to the `/tendermint` mount point to attach the binary and config files to the container.
+The `./build` directory is mounted to the `/tendermint` mount point to attach
+the binary and config files to the container.
 
-For instance, to create a single node testnet:
+To change the number of validators / non-validators change the `localnet-start` Makefile target:
 
 ```
-cd $GOPATH/src/github.com/tendermint/tendermint
-
-# Clear the build folder
-rm -rf ./build
+localnet-start: localnet-stop
+	@if ! [ -f build/node0/config/genesis.json ]; then docker run --rm -v $(CURDIR)/build:/tendermint:Z tendermint/localnode testnet --v 5 --n 3 --o . --populate-persistent-peers --starting-ip-address 192.167.10.2 ; fi
+	docker-compose up
+```
 
-# Build binary
-make build-linux
+The command now will generate config files for 5 validators and 3
+non-validators network.
 
-# Create configuration
-docker run -e LOG="stdout" -v `pwd`/build:/tendermint tendermint/localnode testnet --o . --v 1
+Before running it, don't forget to cleanup the old files:
 
-#Run the node
-docker run -v `pwd`/build:/tendermint tendermint/localnode
+```
+cd $GOPATH/src/github.com/tendermint/tendermint
 
+# Clear the build folder
+rm -rf ./build/node*
 ```
 
 ## Logging
 
-Log is saved under the attached volume, in the `tendermint.log` file. If the `LOG` environment variable is set to `stdout` at start, the log is not saved, but printed on the screen.
+Log is saved under the attached volume, in the `tendermint.log` file. If the
+`LOG` environment variable is set to `stdout` at start, the log is not saved,
+but printed on the screen.
 
 ## Special binaries
 
-If you have multiple binaries with different names, you can specify which one to run with the BINARY environment variable. The path of the binary is relative to the attached volume.
-
+If you have multiple binaries with different names, you can specify which one
+to run with the `BINARY` environment variable. The path of the binary is relative
+to the attached volume.