Create an Alpine Linux image to run the lachesis node for the Fantom cryptocurrency.

FROM alpine:latest as build-stage

ARG LACHESIS_VERSION=release/1.0.0-rc.0

ENV GOROOT=/usr/lib/go 
ENV GOPATH=/go 
ENV PATH=$GOROOT/bin:$GOPATH/bin:/build:$PATH

RUN set -xe; \
  apk add --no-cache --virtual .build-deps \
  # get the build dependencies for go
  git make musl-dev go linux-headers; \
  # install fantom lachesis from github
  mkdir -p ${GOPATH}; cd ${GOPATH}; \
  git clone --single-branch --branch ${LACHESIS_VERSION} https://github.com/Fantom-foundation/go-lachesis.git; \
  cd go-lachesis; \
  make build -j$(nproc); \
  mv build/lachesis /usr/local/bin; \
  rm -rf /go; \
  # remove our build dependencies
  apk del .build-deps; 

FROM alpine:latest as lachesis

# copy the binary 
COPY --from=build-stage /usr/local/bin/lachesis /usr/local/bin/lachesis

COPY run.sh /usr/local/bin

WORKDIR /root

ENV LACHESIS_PORT=5050
ENV LACHESIS_HTTP=18545
ENV LACHESIS_API=eth,ftm,debug,admin,web3,personal,net,txpool
ENV LACHESIS_VERBOSITY=2

EXPOSE ${LACHESIS_PORT}
EXPOSE ${LACHESIS_HTTP}

VOLUME [ "/root/.lachesis" ]

CMD ["run.sh"]

The run.sh just starts the nodes with the ports you set in the environment.

#!/usr/bin/env sh

set -xe

lachesis \
  --port ${LACHESIS_PORT} \
  --http \
  --http.addr "0.0.0.0" \
  --http.port ${LACHESIS_HTTP} \
  --http.api "${LACHESIS_API}" \
  --nousb \
  --verbosity ${LACHESIS_VERBOSITY}

Use docker-compose to define the TCP/UDP ports to expose as well as a data volume to persist the blockchain data.

version: '3.4'

services:
  lachesis:
    image: doublesharp/fantom-lachesis:latest
    restart: always
    ports:
      - '5050:5050'
      - '5050:5050/udp'
      - '18545:18545'
    volumes:
      - lachesis:/root/.lachesis
    environment:
      LACHESIS_VERBOSITY: 2

volumes:
  lachesis: {}

The post Fantom Lachesis Full Node RPC appeared first on Justin Silver.

To use PHP with iconv on Alpine Linux – in a Docker container for example – you need to use the preloadable iconv library, which was previously provided with the gnu-libiconv package, but was removed after Alpine v3.13. After recently rebuilding an Alpine image and running a PHP script that required iconv, I saw the following error:

Notice: iconv(): Wrong charset, conversion from `UTF-8' to `UTF-8//IGNORE' is not allowed

To work around it I installed the gnu-libiconv package from the v3.13 repo. For my projects I went ahead and exported the preloadable binary once it was built as well so that I could just COPY it into the image instead of building it – in my case it’s only for Alpine after all.

You can do this by using an Alpine image tag of alpine:3.13 to add gnu-libiconv and compile /usr/lib/preloadable_libiconv.so, then copy it to a volume to save the binary once the container exits – the output folder is called ./out in this example.

% docker run -v $(pwd)/out:/out -it alpine:3.13 \
/bin/sh -c 'apk add --no-cache gnu-libiconv && cp -f /usr/lib/preloadable_libiconv.so /out/preloadable_libiconv.so'
      
fetch https://dl-cdn.alpinelinux.org/alpine/v3.13/main/x86_64/APKINDEX.tar.gz
fetch https://dl-cdn.alpinelinux.org/alpine/v3.13/community/x86_64/APKINDEX.tar.gz
(1/1) Installing gnu-libiconv (1.15-r3)
Executing busybox-1.32.1-r6.trigger
OK: 8 MiB in 15 packages

% ls -la out/preloadable_libiconv.so                                                                                                                             
-rw-r--r--  1 justin  staff  1005216 Apr 23 14:32 out/preloadable_libiconv.so

Once you have the prebuilt binary you can use COPY in your Dockerfile to use it without needing to build it.

# copy preloadable_libiconv.so from prebuilt
COPY /rootfs/usr/lib/preloadable_libiconv.so /usr/lib/preloadable_libiconv.so
ENV LD_PRELOAD /usr/lib/preloadable_libiconv.so php

If you prefer to install the older package that includes the preloadable binary in a different Alpine Dockerfile you can specify an older repository in a RUN command, like so:

FROM wordpress:5.7.1-php7.4-fpm-alpine
# ... some config
RUN apk add --no-cache \
    --repository http://dl-cdn.alpinelinux.org/alpine/v3.13/community/ \
    --allow-untrusted \
    gnu-libiconv
ENV LD_PRELOAD /usr/lib/preloadable_libiconv.so php

The post Alpine Linux PHP + iconv fix appeared first on Justin Silver.

Some quick tips on how to use apk for Alpine Linux in a Docker environment. Some common use cases might be to install command line tools you will use in scripts, or to compile a PHP extension. In the former you will often be able to access a binary, and not need to worry about polluting much of your Docker layer with extra files. When you need to compile something however – like a PHP extension – you may need several build tools as well as libraries that you don’t need to keep around after you compile the module.

This first example is common for installing command line tools:

RUN apk add --no-cache --update \
  bash curl findutils sed sudo

The next example shows how to compile PHP modules and remove their dependencies after compilation.

RUN set -xe; \
    apk add --no-cache --virtual .build-deps $PHPIZE_DEPS \
      # build tools
      autoconf g++ gcc make \
      # lib tools
      bzip2-dev freetype-dev gettext-dev icu-dev imagemagick-dev libintl libjpeg-turbo-dev \
      #  libmcrypt-dev 
      libpng-dev libxslt-dev libzip-dev \
      ; \
    docker-php-ext-configure \
      gd --with-freetype-dir=/usr/include/ --with-jpeg-dir=/usr/include/ --with-png-dir=/usr/include/ \
      ; \
    docker-php-ext-install -j$(nproc) \
      bcmath bz2 calendar exif gettext gd intl mysqli opcache pcntl pdo_mysql soap xsl zip \
      ; \
    pecl channel-update pecl.php.net && \
    pecl install -o -f \
      redis \
      ; \
    docker-php-ext-enable \
      redis \
      ; \
    runDeps="$( \
      scanelf --needed --nobanner --format '%n#p' --recursive /usr/local/lib/php/extensions \
        | tr ',' '\n' \
        | sort -u \
        | awk 'system("[ -e /usr/local/lib/" $1 " ]") == 0 { next } { print "so:" $1 }' \
    )"; \
      apk add --virtual .phpexts-rundeps $runDeps; \
      apk del .build-deps

The post Using APK for Alpine Linux with Docker appeared first on Justin Silver.