@atomist/automation-client/lib/project/diff/DifferenceEngine.ts

Atomist API for software low-level client

import { GitHubRepoRef } from "../../operations/common/GitHubRepoRef";
import { RepoRef } from "../../operations/common/RepoId";
import { GitCommandGitProject } from "../git/GitCommandGitProject";
import { GitProject } from "../git/GitProject";
import { Chain } from "./Chain";

/**
 * Extracts fingerprints, diffs them, and invokes actions on Github shas that are being compared
 */
export class DifferenceEngine {

    constructor(private readonly githubIssueAuth: GithubIssueAuth, private readonly chains: Array<Chain<any, any>>) {
    }

    /**
     * Run configured diff chains for these shas
     * @param baseSha
     * @param headSha
     */
    public async run(baseSha: string, headSha: string): Promise<void> {
        const project = await this.cloneRepo(this.githubIssueAuth, baseSha);
        const baseFps = await Promise.all(this.chains.map(c => c.extractor.extract(project)));
        await project.checkout(headSha);
        const headFps = await Promise.all(this.chains.map(c => c.extractor.extract(project)));
        const diffs = this.chains.map((c, i) => c.differ.diff(baseFps[i], headFps[i]));
        diffs.map((d, i) => this.chains[i].actions.forEach(a => a.invoke(baseFps[i], headFps[i], d)));
    }

    private cloneRepo(githubIssueAuth: GithubIssueAuth, sha: string): Promise<GitProject> {
        return GitCommandGitProject.cloned(
            { token: githubIssueAuth.githubToken },
            new GitHubRepoRef(githubIssueAuth.owner, githubIssueAuth.repo, githubIssueAuth.sha));
    }
}

/**
 * Details that allow a GitHub issue to be referenced and modified
 */
export interface GithubIssueAuth extends RepoRef {
    githubToken: string;
    issueNumber: number;
}