feat(mattermost): add support for icons

[JosephKav]

• What your PR contributes
  Icon support on MatterMost:

./shoutrrr send -u 'mattermost://Argus@mattermost.example.io:443/xxxxxxxxxxx?icon_emoji=https%3A%2F%2Fraw.githubusercontent.com%2Fcontainrrr%2Fshoutrrr%2Fmain%2Fdocs%2Fshoutrrr-logotype.png' -m 'Icon Test'
./shoutrrr send -u 'mattermost://Argus@mattermost.example.io:443/xxxxxxxxxxx?icon_emoji=smiley' -m 'Icon Test'

• Which issues it solves
  Moving my Argus project to use Shoutrrr. Really want to keep icon support!

• Tests that verify the code your contributing
  I tried adding tests (and most of this code is copied from the Slack service), but couldn't get them to pass. Every other service that has query params seems to include the title param, but that's no supported on MatterMost, so I'm not sure what to do w.r.t this error. Help fixing this would be appreciated!

• Failure [0.000 seconds]
services
/path/to/shoutrrr/pkg/services/services_test.go:48
  when passed the a title param
  /path/to/shoutrrr/pkg/services/services_test.go:57
    should not throw an error for mattermost [It]
    /path/to/shoutrrr/pkg/services/services_test.go:71

    Unexpected error:
        <*errors.errorString | 0xc00030e1b0>: {
            s: "title is not a valid config key [icon icon_emoji icon_url]",
        }
        title is not a valid config key [icon icon_emoji icon_url]
    occurred

    /path/to/shoutrrr/pkg/services/services_test.go:99

• Updates to the documentation
  Done? Let me know if you'd like any more, or changes to them. (Hoping the 'The services does not support any query/param props' would go away with this current commit?)

[piksel]

Every other service that has query params seems to include the title param, but that's no supported on MatterMost.

Just add it anyway. The point is that you should be able to pass title to all services without checking for support. If they don't support it, they are free to just ignore it.
So either put it in the config with key:"title", or manually explicitly ignore it.

[JosephKav]

Thanks for such a quick response and even giving me the commit suggestion for the fix! 😄
(go test ./... locally and all passed)

[codecov]

Codecov Report

Merging #237 (4a9e231) into main (5bca245) will increase coverage by 0.21%.
The diff coverage is 100.00%.

@@            Coverage Diff             @@
##             main     #237      +/-   ##
==========================================
+ Coverage   76.85%   77.07%   +0.21%     
==========================================
  Files          95       95              
  Lines        2826     2844      +18     
==========================================
+ Hits         2172     2192      +20     
+ Misses        474      473       -1     
+ Partials      180      179       -1     

Impacted Files	Coverage Δ
pkg/services/mattermost/mattermost.go	75.00% <100.00%> (+15.00%)	⬆️
pkg/services/mattermost/mattermost_config.go	93.93% <100.00%> (+2.27%)	⬆️
pkg/services/mattermost/mattermost_json.go	100.00% <100.00%> (ø)

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[JosephKav]

Any tips to get the codecov higher?
The two that show up on the files page are return err being missed after the following
if err := resolver.Set(key, vals[0]); err != nil {
or
if err := service.pkr.UpdateConfigFromParams(config, params); err != nil {
Any tests that'd get into these?

[JosephKav]

Could I get some assistance on increasing the CodeCov please?

[piksel]

You can use the generic service compliance tests:

shoutrrr/pkg/services/bark/bark_test.go

Lines 135 to 160 in 5bca245

	Describe("the basic service API", func() {
	Describe("the service config", func() {
	It("should implement basic service config API methods correctly", func() {
	testutils.TestConfigGetInvalidQueryValue(&Config{})
	testutils.TestConfigSetInvalidQueryValue(&Config{}, "bark://:mock-device@host/?foo=bar")
	testutils.TestConfigSetDefaultValues(&Config{})
	testutils.TestConfigGetEnumsCount(&Config{}, 0)
	testutils.TestConfigGetFieldsCount(&Config{}, 9)
	})
	})
	Describe("the service instance", func() {
	BeforeEach(func() {
	httpmock.Activate()
	})
	AfterEach(func() {
	httpmock.DeactivateAndReset()
	})
	It("should implement basic service API methods correctly", func() {
	serviceURL := testutils.URLMust("bark://:devicekey@hostname")
	Expect(service.Initialize(serviceURL, logger)).To(Succeed())
	testutils.TestServiceSetInvalidParamValue(service, "foo", "bar")
	})
	})
	})

[JosephKav]

Hold off on approving this/starting the workflows. Adding more tests and fixing that latest one
All should be sorted now

[piksel]

Great work! I changed the scheme in the test URL, it doesn't matter for the test, but it's confusing to have the name of another service in the URL.

[piksel]

@all-contributors add @JosephKav for code

[allcontributors]

@piksel

I've put up a pull request to add @JosephKav! 🎉