ci: add a script to download Windows installers from AppVeyor (#1485)

When we release a new version, we need to download build artifacts
from AppVeyor and in turn transfer them to our website.

This adds a script to automate the process. Now we can release Windows
installers just by the following steps.

    $ ./appveyor-download v1.2.2
    $ scp td-agent-bit-1.2.2-* fluentbit.io

Signed-off-by: Fujimoto Seiji <[email protected]>

Author: Fujimoto Seiji

ci/appveyor-download

@@ -0,0 +1,92 @@
+#!/usr/bin/env python3
+#
+# This is a simple script to download Windows installers from AppVeyor.
+# Use this script to automate the Windows release process.
+#
+# USAGE
+#
+#   $ appveyor-download v1.2.1  # Download installers for v1.2.1
+#
+
+import json
+import sys
+import os
+import urllib.request
+import datetime
+
+#
+# GLOBAL VARIABLES
+
+GITHUB_URL = 'https://api.github.com/repos/fluent/fluent-bit/statuses/%s'
+
+APPVAYOR_JOBS = 'https://ci.appveyor.com/api/projects/fluent/%s/builds/%s'
+APPVAYOR_LIST = 'https://ci.appveyor.com/api/buildjobs/%s/artifacts'
+APPVAYOR_FILE = 'https://ci.appveyor.com/api/buildjobs/%s/artifacts/%s'
+
+#
+# Util functions
+
+def now():
+    return datetime.datetime.now().strftime('%Y-%m-%d %H:%M:%S')
+
+def usage():
+    print('Usage: appveyor-download VERSION')
+    return -1
+
+def LOG(*args):
+    print(now(), *args, file=sys.stderr)
+
+#
+# REST API
+
+def json_api(url):
+    LOG('Request %s' % url)
+    with urllib.request.urlopen(url) as fp:
+        return json.loads(fp.read().decode())
+
+def build_get(version):
+    resp = json_api(GITHUB_URL % version)
+
+    for item in resp:
+        if item['description'] == 'AppVeyor build succeeded':
+            build_url = item['target_url']
+            break
+    else:
+        raise RuntimeError('No AppVeyor build found: %s' % resp)
+
+    tokens = build_url.split('/')
+
+    return (tokens[-3], tokens[-1])
+
+def jobs_get(project_id, build_id):
+    resp = json_api(APPVAYOR_JOBS % (project_id, build_id))
+    return list(node['jobId'] for node in resp['build']['jobs'])
+
+def filenames_get(job_id):
+    resp = json_api(APPVAYOR_LIST % job_id)
+    return list(node['fileName'] for node in resp)
+
+#
+# Main
+
+def main(args):
+    if not args:
+        return usage()
+
+    project_id, build_id = build_get(args[0])
+
+    for job_id in jobs_get(project_id, build_id):
+        for filename in filenames_get(job_id):
+
+            with urllib.request.urlopen(APPVAYOR_FILE % (job_id, filename)) as fp:
+                data = fp.read()
+                size = len(data)
+
+            outfile = os.path.basename(filename)
+            with open(outfile, 'wb') as fw:
+                fw.write(data)
+
+            LOG('* %s (%s bytes)' % (outfile, size))
+
+if __name__ == '__main__':
+    sys.exit(main(sys.argv[1:]))