function tryFetchDependency()

in src/plugman/install.js [401:483]
53 lines of code
18 McCabe index (conditional complexity)

function tryFetchDependency (dep, install, options) {
    // Handle relative dependency paths by expanding and resolving them.
    // The easy case of relative paths is to have a URL of '.' and a different subdir.
    // TODO: Implement the hard case of different repo URLs, rather than the special case of
    // same-repo-different-subdir.
    let relativePath;
    if (dep.url === '.') {
        // Look up the parent plugin's fetch metadata and determine the correct URL.
        const fetchdata = require('./util/metadata').get_fetch_metadata(install.plugins_dir, install.top_plugin_id);
        if (!fetchdata || !(fetchdata.source && fetchdata.source.type)) {
            relativePath = dep.subdir || dep.id;

            events.emit('warn', 'No fetch metadata found for plugin ' + install.top_plugin_id + '. checking for ' + relativePath + ' in ' + options.searchpath.join(','));

            return Promise.resolve(relativePath);
        }

        // Now there are two cases here: local directory, and git URL.
        if (fetchdata.source.type === 'local') {
            dep.url = fetchdata.source.path;

            return execa.command('git rev-parse --show-toplevel', { cwd: dep.url })
                .catch(err => {
                    if (err.exitCode === 128) {
                        throw new Error('Plugin ' + dep.id + ' is not in git repository. All plugins must be in a git repository.');
                    } else {
                        throw new Error('Failed to locate git repository for ' + dep.id + ' plugin.');
                    }
                })
                .then(({ stdout: git_repo }) => {
                    // Clear out the subdir since the url now contains it
                    const url = path.join(git_repo, dep.subdir);
                    dep.subdir = '';
                    return Promise.resolve(url);
                }).catch(function () {
                    return Promise.resolve(dep.url);
                });
        } else if (fetchdata.source.type === 'git') {
            return Promise.resolve(fetchdata.source.url);
        } else if (fetchdata.source.type === 'dir') {
            // Note: With fetch() independant from install()
            // $md5 = md5(uri)
            // Need a Hash(uri) --> $tmpDir/cordova-fetch/git-hostname.com-$md5/
            // plugin[id].install.source --> searchpath that matches fetch uri

            // mapping to a directory of OS containing fetched plugins
            let tmpDir = fetchdata.source.url;
            tmpDir = tmpDir.replace('$tmpDir', os.tmpdir());

            let pluginSrc = '';
            if (dep.subdir.length) {
                // Plugin is relative to directory
                pluginSrc = path.join(tmpDir, dep.subdir);
            }

            // Try searchpath in dir, if that fails re-fetch
            if (!pluginSrc.length || !fs.existsSync(pluginSrc)) {
                pluginSrc = dep.id;

                // Add search path
                if (options.searchpath.indexOf(tmpDir) === -1) { options.searchpath.unshift(tmpDir); } // place at top of search
            }

            return Promise.resolve(pluginSrc);
        }
    }

    // Test relative to parent folder
    if (dep.url && !isAbsolutePath(dep.url)) {
        relativePath = path.resolve(install.top_plugin_dir, '../' + dep.url);

        if (fs.existsSync(relativePath)) {
            dep.url = relativePath;
        }
    }

    // CB-4770: registry fetching
    if (dep.url === undefined) {
        dep.url = dep.id;
    }

    return Promise.resolve(dep.url);
}