Completed steps up to downloading forge universal jar for 1.8-1.12.

Next step is processing the version.json and transforming it into a deliverable module.

.vscode/launch.json

@@ -8,7 +8,12 @@
             "type": "node",
             "request": "launch",
             "name": "Launch Program",
-            "program": "${workspaceFolder}\\dist\\index.js",
+            "program": "${workspaceFolder}\\src\\index.ts",
+            "args": [
+                "test",
+                "1.12.2",
+                "14.23.5.2847"
+            ],
             "preLaunchTask": "compile",
             "outFiles": [
                 "${workspaceFolder}/dist/**/*.js"

package.json

@@ -36,6 +36,7 @@
   },
   "dependencies": {
     "adm-zip": "^0.4.13",
+    "axios": "^0.19.1",
     "fs-extra": "^8.1.0",
     "yargs": "^15.1.0"
   }

src/index.ts

@@ -1,8 +1,10 @@
 /* tslint:disable:no-shadowed-variable */
 import { writeFile } from 'fs-extra'
 import { resolve as resolvePath } from 'path'
+import { URL } from 'url'
 import yargs from 'yargs'
 import { DistributionStructure } from './model/struct/model/distribution.struct'
+import { ResolverRegistry } from './resolver/ResolverRegistry'
 
 function rootOption(yargs: yargs.Argv) {
     return yargs.option('root', {
@@ -166,6 +168,21 @@ const validateCommand: yargs.CommandModule = {
     }
 }
 
+const testCommand: yargs.CommandModule = {
+    command: 'test <mcVer> <forgeVer>',
+    describe: 'Validate a distribution.json against the spec.',
+    builder: (yargs) => {
+        return namePositional(yargs)
+    },
+    handler: async (argv) => {
+        console.debug(`Invoked test with mcVer ${argv.mcVer} forgeVer ${argv.forgeVer}`)
+        const resolver = ResolverRegistry.getForgeResolver('1.12.2', '14.23.5.2847', 'D:/TestRoot2', 'D:/TestRoot2')
+        if (resolver != null) {
+            await resolver.getModule()
+        }
+    }
+}
+
 // Registering yargs configuration.
 // tslint:disable-next-line:no-unused-expression
 yargs
@@ -174,6 +191,7 @@ yargs
 .command(initCommand)
 .command(generateCommand)
 .command(validateCommand)
+.command(testCommand)
 .demandCommand()
 .help()
 .argv

src/model/struct/repo/BaseMavenRepo.ts

@@ -1,4 +1,7 @@
-import { resolve } from 'path'
+import axios from 'axios'
+import { createWriteStream, mkdirs, pathExists } from 'fs-extra'
+import { dirname, resolve } from 'path'
+import { resolve as resolveURL } from 'url'
 import { MavenUtil } from '../../../util/maven'
 import { BaseFileStructure } from '../BaseFileStructure'
 
@@ -19,8 +22,36 @@ export abstract class BaseMavenRepo extends BaseFileStructure {
 
     public getArtifactByComponents(group: string, artifact: string, version: string,
                                    classifier?: string, extension = 'jar'): string {
-        throw resolve(this.containerDirectory,
+        return resolve(this.containerDirectory,
             MavenUtil.mavenComponentsToString(group, artifact, version, classifier, extension))
     }
 
+    public async artifactExists(path: string) {
+        return pathExists(path)
+    }
+
+    public async downloadArtifact(url: string, group: string, artifact: string, version: string,
+                                  classifier?: string, extension?: string) {
+        const relative = MavenUtil.mavenComponentsToString(group, artifact, version, classifier, extension)
+        const resolvedURL = resolveURL(url, relative).toString()
+        console.debug(`Downloading ${resolvedURL}..`)
+        const response = await axios({
+            method: 'get',
+            url: resolvedURL,
+            responseType: 'stream'
+        })
+        const localPath = resolve(this.containerDirectory, relative)
+        await mkdirs(dirname(localPath))
+        const writer = createWriteStream(localPath)
+        response.data.pipe(writer)
+        // tslint:disable-next-line: no-shadowed-variable
+        return new Promise((resolve, reject) => {
+            writer.on('finish', () => {
+                console.debug(`Completed download of ${resolvedURL}.`)
+                resolve()
+            })
+            writer.on('error', reject)
+        })
+    }
+
 }

src/model/struct/repo/forgerepo.struct.ts

@@ -2,6 +2,9 @@ import { BaseMavenRepo } from './BaseMavenRepo'
 
 export class ForgeRepoStructure extends BaseMavenRepo {
 
+    public static readonly FORGE_GROUP = 'net.minecraftforge'
+    public static readonly FORGE_ARTIFACT = 'forge'
+
     constructor(
         absoluteRoot: string,
         relativeRoot: string
@@ -10,7 +13,10 @@ export class ForgeRepoStructure extends BaseMavenRepo {
     }
 
     public getLocalForge(version: string, classifier?: string) {
-        this.getArtifactByComponents('net.minecraftforge', 'forge', version, classifier, 'jar')
+        return this.getArtifactByComponents(
+            ForgeRepoStructure.FORGE_GROUP,
+            ForgeRepoStructure.FORGE_ARTIFACT,
+            version, classifier, 'jar')
     }
 
 }

src/resolver/ResolverRegistry.ts

@@ -0,0 +1,23 @@
+import { Forge113Adapter } from './forge/adapter/forge113.resolver'
+import { Forge18Adapter } from './forge/adapter/forge18.resolver'
+import { ForgeResolver } from './forge/forge.resolver'
+
+export class ResolverRegistry {
+
+    public static readonly FORGE_ADAPTER_IMPL = [
+        Forge18Adapter,
+        Forge113Adapter
+    ]
+
+    public static getForgeResolver(
+        minecraftVersion: string,
+        forgeVersion: string,
+        absoluteRoot: string, relativeRoot: string): ForgeResolver | undefined {
+        for (const impl of ResolverRegistry.FORGE_ADAPTER_IMPL) {
+            if (impl.isForVersion(minecraftVersion)) {
+                return new impl(absoluteRoot, relativeRoot, minecraftVersion, forgeVersion)
+            }
+        }
+    }
+
+}

src/resolver/baseresolver.ts

@@ -1,13 +1,24 @@
 import { Module } from '../model/spec/module'
+import { VersionUtil } from '../util/versionutil'
 import { Resolver } from './resolver'
 
 export abstract class BaseResolver implements Resolver {
 
+    protected static isVersionAcceptable(version: string, acceptable: number[]): boolean {
+        const versionComponents = VersionUtil.getMinecraftVersionComponents(version)
+        if (versionComponents != null && versionComponents.major === 1) {
+            return acceptable.find((element) => versionComponents.minor === element) != null
+        }
+        return false
+    }
+
     constructor(
         protected absoluteRoot: string,
         protected relativeRoot: string
     ) {}
 
     public abstract getModule(): Promise<Module>
 
+    public abstract isForVersion(version: string): boolean
+
 }

src/resolver/forge/adapter/forge113.resolver.ts

@@ -0,0 +1,27 @@
+import { Module } from '../../../model/spec/module'
+import { ForgeResolver } from '../forge.resolver'
+
+export class Forge113Adapter extends ForgeResolver {
+
+    public static isForVersion(version: string) {
+        return Forge113Adapter.isVersionAcceptable(version, [13, 14, 15])
+    }
+
+    constructor(
+        absoluteRoot: string,
+        relativeRoot: string,
+        minecraftVersion: string,
+        forgeVersion: string
+    ) {
+        super(absoluteRoot, relativeRoot, minecraftVersion, forgeVersion)
+    }
+
+    public async getModule(): Promise<Module> {
+        return null as unknown as Module
+    }
+
+    public isForVersion(version: string): boolean {
+        return Forge113Adapter.isForVersion(version)
+    }
+
+}

src/resolver/forge/adapter/forge18.resolver.ts

@@ -1,10 +1,52 @@
 import { Module } from '../../../model/spec/module'
+import { ForgeRepoStructure } from '../../../model/struct/repo/forgerepo.struct'
 import { ForgeResolver } from '../forge.resolver'
 
 export class Forge18Adapter extends ForgeResolver {
 
+    public static isForVersion(version: string) {
+        return Forge18Adapter.isVersionAcceptable(version, [8, 9, 10, 11, 12])
+    }
+
+    constructor(
+        absoluteRoot: string,
+        relativeRoot: string,
+        minecraftVersion: string,
+        forgeVersion: string
+    ) {
+        super(absoluteRoot, relativeRoot, minecraftVersion, forgeVersion)
+    }
+
     public async getModule(): Promise<Module> {
+        await this.getForgeByVersion()
         return null as unknown as Module
     }
 
+    public isForVersion(version: string) {
+        return Forge18Adapter.isForVersion(version)
+    }
+
+    public async getForgeByVersion() {
+        const forgeRepo = this.repoStructure.getForgeRepoStruct()
+        const artifactVersion = `${this.minecraftVersion}-${this.forgeVersion}`
+        const targetLocalPath = forgeRepo.getLocalForge(artifactVersion, 'universal')
+        console.debug(`Checking for forge version at ${targetLocalPath}..`)
+        if (!await forgeRepo.artifactExists(targetLocalPath)) {
+            console.debug(`Forge not found locally, initializing download..`)
+            await forgeRepo.downloadArtifact(
+                this.REMOTE_REPOSITORY,
+                ForgeRepoStructure.FORGE_GROUP,
+                ForgeRepoStructure.FORGE_ARTIFACT,
+                artifactVersion, 'universal', 'jar')
+        } else {
+            console.debug('Using locally discovered forge.')
+        }
+        console.debug(`Beginning processing of Forge v${this.forgeVersion} (Minecraft ${this.minecraftVersion})`)
+    }
+
+    // TODO
+    // extract manifest
+    // parse manifest
+    // return module
+
 }

src/resolver/forge/forge.resolver.ts

@@ -1,33 +1,20 @@
-import { Module } from '../../model/spec/module'
 import { RepoStructure } from '../../model/struct/repo/repo.struct'
 import { BaseResolver } from '../baseresolver'
-import { Forge18Adapter } from './adapter/forge18.resolver'
 
 export abstract class ForgeResolver extends BaseResolver {
 
-    public static getResolver(version: string) {
-        return ForgeResolver.ADAPTER_LIST[version]
-    }
-
-    // tslint:disable: object-literal-key-quotes
-    private static readonly ADAPTER_LIST: {[version: string]: any} = {
-        '1.8': Forge18Adapter,
-        '1.9': Forge18Adapter,
-        '1.10': Forge18Adapter,
-        '1.11': Forge18Adapter,
-        '1.12': Forge18Adapter
-    }
+    protected readonly REMOTE_REPOSITORY = 'https://files.minecraftforge.net/maven/'
 
     protected repoStructure: RepoStructure
 
     constructor(
         absoluteRoot: string,
-        relativeRoot: string
+        relativeRoot: string,
+        protected minecraftVersion: string,
+        protected forgeVersion: string
     ) {
         super(absoluteRoot, relativeRoot)
         this.repoStructure = new RepoStructure(absoluteRoot, relativeRoot)
     }
 
-    public abstract getModule(): Promise<Module>
-
 }