Status Chart: Add Combined PR Age and GitHub API script

.gitignore

@@ -11,3 +11,9 @@ __pycache__/
 # Ignore submodules in other branches.
 /llvm-project/
 /vcpkg/
+
+# Ignore installed packages.
+/node_modules/
+
+# Ignore secret credentials.
+/.env

gather_stats.js

@@ -0,0 +1,117 @@
+// Copyright (c) Microsoft Corporation.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+
+const fs = require('fs');
+
+const cliProgress = require('cli-progress');
+const dotenv = require('dotenv');
+const { DateTime, Duration } = require('luxon');
+const { Octokit } = require('@octokit/rest');
+
+{
+    const result = dotenv.config();
+
+    if (result.error) {
+        throw result.error;
+    }
+
+    if (process.env.SECRET_GITHUB_PERSONAL_ACCESS_TOKEN === undefined) {
+        throw 'Missing SECRET_GITHUB_PERSONAL_ACCESS_TOKEN key in .env file.'
+    }
+}
+
+const progress_bar = new cliProgress.SingleBar(
+    { format: '{bar} {percentage}% | ETA: {eta}s | {value}/{total} {name}' },
+    cliProgress.Presets.shades_classic);
+let progress_value = 0;
+
+progress_bar.start(1000 /* placeholder total */, 0, { name: 'PRs and issues received' });
+
+const octokit = new Octokit({
+    auth: process.env.SECRET_GITHUB_PERSONAL_ACCESS_TOKEN,
+});
+
+octokit.paginate(
+    octokit.issues.listForRepo,
+    {
+        owner: 'microsoft',
+        repo: 'STL',
+        state: 'all',
+    },
+    response => {
+        progress_value += response.data.length;
+
+        // PRs/issues are received in descending order by default.
+        // Deleted PRs/issues are skipped, so we recalculate the expected total.
+        // If the last PR/issue we received was number N, we can expect to receive N - 1 more: numbers [1, N - 1].
+        const remaining = response.data[response.data.length - 1]['number'] - 1;
+
+        progress_bar.setTotal(progress_value + remaining);
+        progress_bar.update(progress_value);
+
+        return response.data.map(item => ({
+            opened: DateTime.fromISO(item['created_at']),
+            closed: DateTime.fromISO(item['closed_at'] ?? '2100-01-01'),
+            is_pr: item['pull_request'] !== undefined,
+            label_names: item['labels'].map(label => label['name']),
+        }));
+    }
+).then(transformed_output => {
+    progress_bar.setTotal(progress_value); // Just in case PR/issue number 1 was deleted,
+    progress_bar.update(progress_value); // which would prevent the progress bar from reaching 100%.
+    progress_bar.stop();
+
+    const begin = DateTime.fromISO('2019-09-03' + 'T23:00:00-07');
+    const now = DateTime.local();
+
+    let str = '// Copyright (c) Microsoft Corporation.\n';
+    str += '// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception\n';
+    str += '\n';
+    const generated_file_warning_comment = '// Generated file - DO NOT EDIT manually!\n';
+    str += generated_file_warning_comment;
+    str += 'const daily_table = [\n';
+
+    progress_bar.start(Math.ceil(now.diff(begin, 'days').as('days')), 0, { name: 'days analyzed' });
+
+    for (let when = begin; when < now; when = when.plus({ days: 1 })) {
+        let num_pr = 0;
+        let num_issue = 0;
+        let num_bug = 0;
+        let combined_pr_age = Duration.fromObject({ seconds: 0 });
+
+        for (const elem of transformed_output) {
+            if (when < elem.opened || elem.closed < when) {
+                // This PR/issue wasn't active; do nothing.
+            } else if (elem.is_pr) {
+                ++num_pr;
+                combined_pr_age = combined_pr_age.plus(when.diff(elem.opened, 'seconds'));
+            } else if (elem.label_names.includes('cxx20')) {
+                // Avoid double-counting C++20 Features and GitHub Issues.
+            } else {
+                ++num_issue;
+
+                if (elem.label_names.includes('bug')) {
+                    ++num_bug;
+                }
+            }
+        }
+
+        str += '    { ';
+        str += [
+            `date: '${when.toISODate()}'`,
+            `pr: ${num_pr}`,
+            `issue: ${num_issue}`,
+            `bug: ${num_bug}`,
+            `months: ${Number.parseFloat(combined_pr_age.as('months')).toFixed(2)}`,
+            '},\n'].join(', ');
+
+        progress_bar.increment();
+    }
+
+    str += '];\n';
+    str += generated_file_warning_comment;
+
+    progress_bar.stop();
+
+    fs.writeFileSync('./daily_table.js', str);
+});