gfdatasource, but in Python

gfdatasource/Dockerfile

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+FROM alpine:3.4
+LABEL works.weave.role=system
+RUN apk update && apk upgrade && apk add python3
+RUN python3 -m ensurepip && pip3 install --upgrade pip
+COPY requirements.txt /
+RUN pip3 install -r requirements.txt
+COPY gfdatasource /
+ENTRYPOINT ["/gfdatasource"]

gfdatasource/gfdatasource

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+#!/usr/bin/env python3
+
+"""Tools for maintaining Grafana datasources."""
+
+import argparse
+import attr
+import requests
+import sys
+from urllib.parse import ParseResult, urlparse
+
+
+@attr.s
+class BasicAuthCredentials(object):
+    username = attr.ib()
+    password = attr.ib()
+
+    def to_json_dict(self):
+        return {
+            'basicAuth': True,
+            'basicAuthUser': self.username,
+            'basicAuthPassword': self.password
+        }
+
+
+@attr.s
+class DataSource(object):
+    """A data source for Grafana."""
+
+    name = attr.ib()
+    type = attr.ib()
+    url = attr.ib()
+    access = attr.ib()
+    credentials = attr.ib()
+
+    def to_json_dict(self):
+        data = {
+            'name': self.name,
+            'type': self.type,
+            'url': self.url,
+            'access': self.access,
+        }
+        if self.credentials:
+            data.update(self.credentials)
+        return data
+
+
+@attr.s
+class GrafanaAPI(object):
+    """HTTP client for Grafana's API."""
+
+    base_url = attr.ib()
+    credentials = attr.ib()
+
+    def _get_session(self):
+        if not self.credentials:
+            return requests.Session()
+        return requests.Session(
+            auth=(self.credentials.username, self.credentials.password))
+
+    def update_datasource(self, data_source):
+        return self._get_session().post(
+            '/'.join([self.base_url, 'datasource']),
+            json=data_source.to_json_dict())
+
+
+def make_parser():
+    parser = argparse.ArgumentParser(prog='gfdatasource')
+    parser.add_argument(
+        '--grafana-url', type=urlparse,
+        default='http',
+        help="URL of Grafana API",
+    )
+    parser.add_argument(
+        '--data-source-url', type=urlparse,
+        help="URL of data source",
+    )
+    parser.add_argument(
+        '--access', type=str, default='proxy',
+        help="Type of access used by Grafana to the data source",
+    )
+    parser.add_argument(
+        '--type', type=str, default='prometheus',
+        help="The type of data source",
+    )
+    parser.add_argument(
+        '--name', type=str, default='Prometheus',
+        help="The name of the data source",
+    )
+    parser.add_argument(
+        '--update-interval', type=int, default=10,
+        help="How frequently to update Grafana, in seconds",
+    )
+    return parser
+
+
+def _split_creds(url):
+    creds = BasicAuthCredentials(url.username, url.password)
+    netloc = url.netloc.split('@')[1] if '@' in url.netloc else url.netloc
+    url = ParseResult(
+        scheme=url.scheme,
+        netloc=netloc,
+        path=url.path,
+        params=url.params,
+        query=url.query,
+        fragment=url.fragment,
+    )
+    return url, creds
+
+
+def main():
+    parser = make_parser()
+    opts = parser.parse_args(sys.argv[1:])
+    grafana_url, grafana_creds = _split_creds(opts.grafana_url)
+    grafana_api = GrafanaAPI(base_url=grafana_url, credentials=grafana_creds)
+    datasource_url, datasource_creds = _split_creds(opts.data_source_url)
+    datasource = DataSource(base_url=datasource_url, credentials=datasource_creds)
+    while True:
+        grafana_api.update_datasource(datasource)
+        time.sleep(opts.update_interval)
+
+
+main()

gfdatasource/requirements.txt

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+attrs==16.3.0
+requests==2.12.3