How are evolution images attached to email reports? Ours show missing images

mpj · May 16, 2024, 5:58am

Hi, I’ve created a custom report on Matomo 5 which creates an evolution with a filter on one page.
When I download the email report where this custom report is attached to, it looks like this:

But sending it, the image is always missing:

Not sure if this is relevant, but we have a custom config with 2 versions of Matomo running on the same database server.
One is used for tracking and has a config which blocks logins by using maintenance mode.
The other does the heavy lifting and processing but can only be accessed through a tunnel. The second one is the one sending the emails.

mpj · May 21, 2024, 8:58am

Just sent the report to a different email address as I can’t have a look at the full source in Outlook.
The image is attached in Thunderbird (while it’s completely missing in Outlook).

The image is added to the email body like this:

<img alt=3D"" src=3D"cid:CustomReports_getCustomReport_idCustom=
Report--15" height=3D"200" width=3D"700" margin=3D"0 auto">

And it’s attached to the email like this:

--b2=_79eO9p5Ze9d7NpcpNOmkKdDnezwTyxDQ7xKP8m9N2A
Content-Type: image/png; name="=?utf-8?Q?Author_guidelines_evolution_-_week_May_13?=
 =?utf-8?Q?=E2=80=89-=E2=80=8919,_2024_-_3_-_Report_3.png?="
Content-Transfer-Encoding: base64
Content-ID: <=?us-ascii?Q?CustomReports=5FgetCustomReport=5FidCustomRepor?=
 =?us-ascii?Q?t--15?=>
Content-Disposition: inline; filename="=?utf-8?Q?Author_guidelines_evolution_-_week_May_13?=
 =?utf-8?Q?=E2=80=89-=E2=80=8919,_2024_-_3_-_Report_3.png?="

iVBOR...

--b2=_79eO9p5Ze9d7NpcpNOmkKdDnezwTyxDQ7xKP8m9N2A--

I don’t know enough about emails to tell where the problem sits.

heurteph-ei · June 6, 2024, 10:57am

Hi @mpj
I think there is a known issue about this:

github.com/matomo-org/matomo

Image attachments for scheduled reports not working in Outlook

opened 10:43PM - 09 Jan 23 UTC

Starker3

Bug c: Consistent Reports & Analytics UX c: Email Reports

For HTML based email reports, there seems to be certain circumstances where Outl…ook shows a "Attachment not found" error related to how the images are attached, for example: `<img data-imagetype="AttachmentByCid" data-imageerror="AttNotFound" originalsrc="cid:CustomReports_getCustomReport_idCustomReport--10" border="0" id="x__x0000_i1028" style="width:524.99pt;height:149.99pt;">` However, the same email reports work in other mail providers, such as Gmail. After some further investigation, it seems that this post is perhaps related: https://answers.microsoft.com/en-us/outlook_com/forum/all/cid-image-embeds-are-not-loading-properly-in/37cef54a-e9cf-4591-9f39-a0b5e539b178 The post above mentions that in order for the `cid` images to load, they needed to change the code to change where the image is attached (See second last post)

mpj · June 7, 2024, 8:26am

Thanks. For me it’s not a general issue but seems to be specific to custom reports as the “Visists Summary” is working in emails.
Having a look at the email source, this could be a naming issue with the Content ID.

# Working:
<img alt=3D"" src=3D"cid:VisitsSummary_get" height=3D"200" widt=
h=3D"700" margin=3D"0 auto">
...
Content-ID: <VisitsSummary_get>

# Not working:
<img alt=3D"" src=3D"cid:CustomReports_getCustomReport_idCustom=Report--15"
  height=3D"200" width=3D"700" margin=3D"0 auto">
...
Content-ID: <=?us-ascii?Q?CustomReports=5FgetCustomReport=5FidCustomRepor?=
 =?us-ascii?Q?t--15?=>

heurteph-ei · June 7, 2024, 1:05pm

Hi @mpj
Very interesting: I think you could add this valuable information to the GitHub ticket. I encounter the same issue with Outlook either (but did not take time to investigate in it, I though it was a problem specific to our installation).