Add git urls parsing and tests

2 files changed, 138 insertions, 0 deletions

diff --git a/lib/utils/command.js b/lib/utils/command.js
new file mode 100644
index 0000000..f395fa1
--- /dev/null
+++ b/lib/utils/command.js
@@ -0,0 +1,19 @@
+var childProcess = require('child_process');
+var Promise = require('./promise');
+
+// On borwser, command execution is not possible
+var isAvailable = childProcess && childProcess.exec;
+
+// Execute a command
+function exec(command, options) {
+    if (!isAvailable) {
+        return Promise.reject(new Error('Command execution is not possible on this platform'));
+    }
+
+    return Promise.nfcall(childProcess.exec, command, options);
+}
+
+module.exports = {
+    isAvailable: isAvailable,
+    exec: exec
+};
diff --git a/lib/utils/git.js b/lib/utils/git.js
new file mode 100644
index 0000000..6e37b14
--- /dev/null
+++ b/lib/utils/git.js
@@ -0,0 +1,119 @@
+var _ = require('lodash');
+var path = require('path');
+var crc = require('crc');
+var URI = require('urijs');
+var pathUtil = require('./path');
+
+var Promise = require('./promise');
+var command = require('./command');
+var fs = require('./fs');
+
+var GIT_PREFIX = 'git+';
+var GIT_TMP = null;
+
+
+// Check if an url is a git dependency url
+function isGitUrl(giturl) {
+    return (giturl.indexOf(GIT_PREFIX) === 0);
+}
+
+// Parse and extract infos
+function parseGitUrl(giturl) {
+    var ref, uri, fileParts, filepath;
+
+    if (!isGitUrl(giturl)) return null;
+    giturl = giturl.slice(GIT_PREFIX.length);
+
+    uri = new URI(giturl);
+    ref = uri.fragment() || 'master';
+    uri.fragment(null);
+
+    // Extract file inside the repo (after the .git)
+    fileParts =uri.path().split('.git');
+    filepath = fileParts.length > 1? fileParts.slice(1).join('.git') : '';
+    if (filepath[0] == '/') filepath = filepath.slice(1);
+
+    // Recreate pathname without the real filename
+    uri.path(_.first(fileParts)+'.git');
+
+    return {
+        host: uri.toString(),
+        ref: ref || 'master',
+        filepath: filepath
+    };
+}
+
+// Clone a git repo from a specific ref
+function cloneGitRepo(host, ref) {
+    ref = ref || 'master';
+
+    return Promise()
+
+    // Create temporary folder to store git repos
+    .then(function() {
+        if (GIT_TMP) return;
+        return fs.tmp.dir()
+            .then(function(_tmp) {
+                GIT_TMP = _tmp;
+            });
+    })
+
+    // Return or clone the git repo
+    .then(function() {
+        // Unique ID for repo/ref combinaison
+        var repoId = crc.crc32(host+'#'+ref).toString(16);
+
+        // Absolute path to the folder
+        var repoPath = path.resolve(GIT_TMP, repoId);
+
+        return fs.exists(repoPath)
+            .then(function(doExists) {
+                if (doExists) return;
+
+                // Clone repo
+                return command.exec('git clone '+host+' '+repoPath)
+                .then(function() {
+                    return command.exec('git checkout '+ref, { cwd: repoPath });
+                });
+            })
+            .thenResolve(repoPath);
+    });
+}
+
+// Get file from a git repo
+function resolveFileFromGit(giturl) {
+    if (_.isString(giturl)) giturl = parseGitUrl(giturl);
+    if (!giturl) return Promise(null);
+
+    // Clone or get from cache
+    return cloneGitRepo(giturl.host, giturl.ref)
+    .then(function(repo) {
+
+        // Resolve relative path
+        return path.resolve(repo, giturl.filepath);
+    });
+}
+
+// Return root of git repo from a filepath
+function resolveGitRoot(filepath) {
+    var relativeToGit, repoId;
+
+    // No git repo cloned, or file is not in a git repository
+    if (!GIT_TMP || !pathUtil.isInRoot(GIT_TMP, filepath)) return null;
+
+    // Extract first directory (is the repo id)
+    relativeToGit = path.relative(GIT_TMP, filepath);
+    repoId = _.first(relativeToGit.split(path.sep));
+    if (!repoId) return;
+
+    // Return an absolute file
+    return path.resolve(GIT_TMP, repoId);
+}
+
+
+module.exports = {
+    isUrl: isGitUrl,
+    parseUrl: parseGitUrl,
+    resolveFile: resolveFileFromGit,
+    resolveRoot: resolveGitRoot
+};