Support for --add-host (railwayapp#1119)

* Add example

* Attempt to add tests

* Add hosts works, validated by tests

* Add test to validate that the build does not work when there are no hosts attached

* Fix naming conventions

* Use the same argument as Docker

* Use the same argument as Docker

* Clean up after tests

* Clean linting

* Fix clippy linting

* add snapshot test for node fetch network

* remove build command from node-fetch-network

* update snapshot

* add back build command

* Fix package.json

* Fix build, make sure to use --network=host when providing add hosts

* Fix clippy

---------

Co-authored-by: Jake Runzer <[email protected]>

examples/node-fetch-network/.gitignore

@@ -0,0 +1,169 @@
+# Based on https://raw.githubusercontent.com/github/gitignore/main/Node.gitignore
+
+# Logs
+
+logs
+_.log
+npm-debug.log_
+yarn-debug.log*
+yarn-error.log*
+lerna-debug.log*
+.pnpm-debug.log*
+
+# Diagnostic reports (https://nodejs.org/api/report.html)
+
+report.[0-9]_.[0-9]_.[0-9]_.[0-9]_.json
+
+# Runtime data
+
+pids
+_.pid
+_.seed
+\*.pid.lock
+
+# Directory for instrumented libs generated by jscoverage/JSCover
+
+lib-cov
+
+# Coverage directory used by tools like istanbul
+
+coverage
+\*.lcov
+
+# nyc test coverage
+
+.nyc_output
+
+# Grunt intermediate storage (https://gruntjs.com/creating-plugins#storing-task-files)
+
+.grunt
+
+# Bower dependency directory (https://bower.io/)
+
+bower_components
+
+# node-waf configuration
+
+.lock-wscript
+
+# Compiled binary addons (https://nodejs.org/api/addons.html)
+
+build/Release
+
+# Dependency directories
+
+node_modules/
+jspm_packages/
+
+# Snowpack dependency directory (https://snowpack.dev/)
+
+web_modules/
+
+# TypeScript cache
+
+\*.tsbuildinfo
+
+# Optional npm cache directory
+
+.npm
+
+# Optional eslint cache
+
+.eslintcache
+
+# Optional stylelint cache
+
+.stylelintcache
+
+# Microbundle cache
+
+.rpt2_cache/
+.rts2_cache_cjs/
+.rts2_cache_es/
+.rts2_cache_umd/
+
+# Optional REPL history
+
+.node_repl_history
+
+# Output of 'npm pack'
+
+\*.tgz
+
+# Yarn Integrity file
+
+.yarn-integrity
+
+# dotenv environment variable files
+
+.env
+.env.development.local
+.env.test.local
+.env.production.local
+.env.local
+
+# parcel-bundler cache (https://parceljs.org/)
+
+.cache
+.parcel-cache
+
+# Next.js build output
+
+.next
+out
+
+# Nuxt.js build / generate output
+
+.nuxt
+dist
+
+# Gatsby files
+
+.cache/
+
+# Comment in the public line in if your project uses Gatsby and not Next.js
+
+# https://nextjs.org/blog/next-9-1#public-directory-support
+
+# public
+
+# vuepress build output
+
+.vuepress/dist
+
+# vuepress v2.x temp and cache directory
+
+.temp
+.cache
+
+# Docusaurus cache and generated files
+
+.docusaurus
+
+# Serverless directories
+
+.serverless/
+
+# FuseBox cache
+
+.fusebox/
+
+# DynamoDB Local files
+
+.dynamodb/
+
+# TernJS port file
+
+.tern-port
+
+# Stores VSCode versions used for testing VSCode extensions
+
+.vscode-test
+
+# yarn v2
+
+.yarn/cache
+.yarn/unplugged
+.yarn/build-state.yml
+.yarn/install-state.gz
+.pnp.\*

examples/node-fetch-network/fetchData.js

@@ -0,0 +1,23 @@
+import fetch from 'node-fetch';
+
+const url = process.env.REMOTE_URL;
+
+if (!url) {
+    console.error('REMOTE_URL is not defined in the environment variables.');
+    process.exit(1);
+}
+
+fetch(url)
+    .then(response => {
+        if (!response.ok) {
+            throw new Error(`Network response was not ok: ${response.statusText}`);
+        }
+        return response.statusText;
+    })
+    .then(data => {
+        console.log('Fetched data:', data);
+    })
+    .catch(error => {
+        console.error('Fetching data failed:', error);
+        process.exit(1);
+    });

examples/node-fetch-network/package.json

@@ -0,0 +1,17 @@
+{
+  "type": "module",
+  "name": "your-project-name",
+  "version": "1.0.0",
+  "description": "A project to fetch data from a remote URL",
+  "main": "index.js",
+  "scripts": {
+    "build": "echo $REMOTE_URL && node fetchData.js",
+    "start": "node fetchData.js"
+  },
+  "dependencies": {
+    "dotenv": "^10.0.0",
+    "node-fetch": "^3.0.0"
+  },
+  "author": "Your Name",
+  "license": "MIT"
+}

src/main.rs

@@ -145,6 +145,10 @@ enum Commands {
         #[arg(long)]
         docker_host: Option<String>,
 
+        /// Adds hosts to the Docker build
+        #[arg(long, global = true)]
+        add_host: Vec<String>,
+
         /// Specify if Docker client should verify the TLS (Transport Layer Security) certificates
         #[arg(long)]
         docker_tls_verify: Option<String>,
@@ -255,6 +259,7 @@ async fn main() -> Result<()> {
             cache_from,
             docker_host,
             docker_tls_verify,
+            add_host,
             inline_cache,
             no_error_without_start,
             cpu_quota,
@@ -288,6 +293,7 @@ async fn main() -> Result<()> {
                 no_error_without_start,
                 incremental_cache_image,
                 cpu_quota,
+                add_host,
                 memory,
                 verbose,
             };

src/nixpacks/builder/docker/docker_helper.rs

@@ -0,0 +1,59 @@
+use serde::{Deserialize, Serialize};
+use std::collections::HashMap;
+use std::error::Error;
+use std::process::Command;
+use std::str;
+
+#[derive(Serialize, Deserialize, Debug)]
+struct ContainerInfoFromDocker {
+    #[serde(rename = "Name")]
+    name: String,
+    #[serde(rename = "IPv4Address")]
+    ipv4_address: String,
+}
+
+pub struct ContainerInfo {
+    pub name: String,
+    pub ipv4_address: String,
+    pub ipv4_address_without_mask: String,
+}
+
+type Containers = HashMap<String, ContainerInfo>;
+
+pub struct DockerHelper {}
+
+impl DockerHelper {
+    pub fn containers_in_network(network: &str) -> Result<Containers, Box<dyn Error>> {
+        let output = Command::new("docker")
+            .arg("network")
+            .arg("inspect")
+            .arg(network)
+            .arg("-f")
+            .arg("{{json .Containers}}")
+            .output()?;
+
+        if output.status.success() {
+            let containers_string = str::from_utf8(&output.stdout)?;
+            let containers: HashMap<String, ContainerInfoFromDocker> =
+                serde_json::from_str(containers_string)?;
+
+            let mut vec = Vec::new();
+            for info in containers.values() {
+                let ipv4 = info.ipv4_address.split('/').next().unwrap();
+                let container_info = ContainerInfo {
+                    name: info.name.clone(),
+                    ipv4_address: info.ipv4_address.clone(),
+                    ipv4_address_without_mask: ipv4.to_string(),
+                };
+                vec.push(container_info);
+            }
+
+            return Ok(vec
+                .into_iter()
+                .map(|info| (info.name.clone(), info))
+                .collect());
+        }
+
+        Err("Docker command failed".into())
+    }
+}

src/nixpacks/builder/docker/docker_image_builder.rs

@@ -155,14 +155,22 @@ impl DockerImageBuilder {
             .arg("build")
             .arg(&output.root)
             .arg("-f")
-            .arg(&output.get_absolute_path("Dockerfile"))
+            .arg(output.get_absolute_path("Dockerfile"))
             .arg("-t")
             .arg(name);
 
         if self.options.verbose {
             docker_build_cmd.arg("--progress=plain");
         }
 
+        if !self.options.add_host.is_empty() {
+            for host in &self.options.add_host {
+                docker_build_cmd.arg("--add-host").arg(host);
+            }
+
+            docker_build_cmd.arg("--network").arg("host");
+        }
+
         if self.options.quiet {
             docker_build_cmd.arg("--quiet");
         }