Merge ~sajoupa/charm-k8s-telegraf:image-dockerhub into charm-k8s-telegraf:master

[Laurent Sesquès]

use the telegrafcharmers/telegraf image from dockerhub by default, update README and tests.

[🤖 Canonical IS Merge Bot (canonical-is-mergebot)]

This merge proposal is being monitored by mergebot. Change the status to Approved to merge.

[Tom Haddon (mthaddon)]

LGTM, thx

review: Approve

[🤖 Canonical IS Merge Bot (canonical-is-mergebot)]

Change successfully merged at revision e37ae7199bc800dc966884b178b30c5b9b39d8ed

diff --git a/.flake8 b/.flake8
index 7310f0e..41512a8 100644
--- a/.flake8
+++ b/.flake8
@@ -1,5 +1,5 @@
 [flake8]
-max-line-length = 119
+max-line-length = 120
 select: E,W,F,C,N
 exclude:
   venv
diff --git a/README.md b/README.md
index c8adcfa..7a29599 100644
--- a/README.md
+++ b/README.md
@@ -13,12 +13,40 @@ Telegraf is plugin-driven and has the concept of 4 distinct plugin types:
 Deploying telegraf in a k8s environment makes sense to monitor services or 3rd party
 APIs, not to gather system stats (telegraf would only monitor itself in its container).
 
+It is possible for instance to deploy telegraf on k8s to gather metrics about a github
+repository with the github input plugin, weather data with the OpenWeatherMap input
+plugin, or check HTTP/HTTPS connections with the http_response plugin.
+
 ## Usage
 
-juju deploy ./telegraf.charm --config inputs='[[inputs.github]]
-  repositories = [
-          "influxdata/telegraf"
-  ]' --config image_path='localhost:32000/telegraf:latest'
+Deploy the charm to a k8s juju model, for example:
+
+    juju deploy cs:~telegraf-charmers/telegraf --config inputs='[[inputs.github]]
+      repositories = [
+              "influxdata/telegraf"
+      ]'
+
+In this case, telegraf will expose its metrics using the charm's default output plugin,
+prometheus on tcp port 9103.
+
+## Using a custom image
+
+By default the charm will use the telegrafcharmers/telegraf:edge image from dockerhub.
+To build and push a custom image:
+
+    git clone  https://git.launchpad.net/charm-k8s-telegraf
+    cd charm-k8s-telegraf
+    make image-build
+    docker tag telegraf:latest localhost:32000/telegraf
+    docker push localhost:32000/telegraf
+
+Then, to use your new image, either replace the `deploy` step above with:
+
+    juju deploy ./telegraf.charm --config image_path=localhost:32000/telegraf
+
+or, if you've already deployed telegraf:
+
+    juju config telegraf image_path=localhost:32000/telegraf
 
 ## Testing
 
diff --git a/config.yaml b/config.yaml
index bf3039d..fbe14b5 100644
--- a/config.yaml
+++ b/config.yaml
@@ -59,7 +59,7 @@ options:
       The location of the image to use, e.g. "registry.example.com/telegraf:v1".
 
       This setting is required.
-    default: ''
+    default: 'telegrafcharmers/telegraf:edge'
   image_username:
     type: string
     description: >
diff --git a/tests/unit/scenario.py b/tests/unit/scenario.py
index d74855a..e60569b 100644
--- a/tests/unit/scenario.py
+++ b/tests/unit/scenario.py
@@ -31,8 +31,13 @@ JUJU_DEFAULT_CONFIG = get_juju_default_config()
 TEST_JUJU_CONFIG = {
     'defaults': {
         'config': {},
-        'logger': ["ERROR:charm:Required Juju config item(s) not set : image_path"],
-        'expected': 'Required Juju config item(s) not set : image_path',
+        'logger': [],
+        'expected': False,
+    },
+    'missing_required_config': {
+        'config': {'inputs': ''},
+        'logger': ["ERROR:charm:Required Juju config item(s) not set : inputs"],
+        'expected': 'Required Juju config item(s) not set : inputs',
     },
     'good_config': {
         'config': {'image_path': 'telegraf:latest'},
@@ -41,7 +46,6 @@ TEST_JUJU_CONFIG = {
     },
     'empty_ports_list': {
         'config': {
-            'image_path': 'telegraf:latest',
             'open_ports': '',
         },
         'logger': ['ERROR:charm:Required Juju config item(s) not set : open_ports'],
@@ -49,7 +53,6 @@ TEST_JUJU_CONFIG = {
     },
     'port_out_of_range': {
         'config': {
-            'image_path': 'telegraf:latest',
             'open_ports': '9103:tcp,-1:udp',
             'inputs': '[[inputs.internal]]',
             'outputs': '[[outputs.prometheus_client]]',
@@ -59,7 +62,6 @@ TEST_JUJU_CONFIG = {
     },
     'invalid_protocol': {
         'config': {
-            'image_path': 'telegraf:latest',
             'open_ports': '9103:tcp,6343:wrong_protocol',
             'inputs': '[[inputs.internal]]',
             'outputs': '[[outputs.prometheus_client]]',
@@ -77,7 +79,6 @@ TEST_JUJU_CONFIG = {
     },
     'invalid_port_number': {
         'config': {
-            'image_path': 'telegraf:latest',
             'open_ports': 'not_an_int:tcp',
             'inputs': '[[inputs.internal]]',
             'outputs': '[[outputs.prometheus_client]]',
@@ -129,7 +130,6 @@ TEST_MAKE_OPEN_PORTS_LIST = {
 TEST_MAKE_POD_SPEC = {
     'basic': {
         'config': {
-            'image_path': 'telegraf:latest',
             'agent_conf': ('[agent]\n' ' interval = "10s"\n' ' round_interval = true'),
         },
         'pod_spec': {
@@ -138,7 +138,7 @@ TEST_MAKE_POD_SPEC = {
                 {
                     'name': 'telegraf',
                     'imageDetails': {
-                        'imagePath': 'telegraf:latest',
+                        'imagePath': 'telegrafcharmers/telegraf:edge',
                     },
                     'imagePullPolicy': 'Always',
                     'ports': [{'containerPort': 9103, 'protocol': 'TCP', 'name': '9103-tcp'}],
diff --git a/tests/unit/test_charm.py b/tests/unit/test_charm.py
index 030e31c..3ee5524 100644
--- a/tests/unit/test_charm.py
+++ b/tests/unit/test_charm.py
@@ -66,20 +66,19 @@ class TestTelegrafK8sCharm(unittest.TestCase):
 
         self.harness.update_config(JUJU_DEFAULT_CONFIG)
 
-        self.harness.set_leader(True)
-        self.harness.charm._configure_pod(mock_event)
-        self.assertEqual(
-            self.harness.charm.unit.status, BlockedStatus('Required Juju config item(s) not set : image_path')
-        )
-
         for is_leader in [True, False]:
             self.harness.set_leader(is_leader)
             self.harness.charm.unit.status = BlockedStatus("Testing")
-            self.harness.update_config({'image_path': 'telegraf:latest'})
             self.harness.charm._configure_pod(mock_event)
             self.assertEqual(self.harness.charm.unit.status, ActiveStatus())
             self.harness.update_config(JUJU_DEFAULT_CONFIG)  # You need to clean the config after each run
 
+        self.harness.set_leader(True)
+        self.harness.update_config({'inputs': ''})
+        self.harness.charm._configure_pod(mock_event)
+        self.assertEqual(self.harness.charm.unit.status, BlockedStatus("Required Juju config item(s) not set : inputs"))
+        self.harness.update_config(JUJU_DEFAULT_CONFIG)  # You need to clean the config after each run
+
     def test_make_open_ports_list(self):
         """Test the _make_open_ports_list function."""