Programmers who generate email know that Gmail does not display images directly from the source defined in the email message HTML; a Google proxy server requests the image from the source and caches it, and Gmail displays the image from the cache.
For how long does Google keep the cached version of the image? In other words, how much time must transpire before Google's proxy server must request the image from the source again?
I've searched for the answer to this on the web and come up with no answer.
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I am creating an app for google assistant which will collect data while a user plays a game and then send that data to a project database. The API I am using to sent the data (synapse) requires it to be in file format, however, I can't find a way to create a file for the data due to the nature of google assistant apps. Am I overlooking a way to do this/is there a way to get around this and send the data somewhere else to make it into file format? The data is stored in a JSON object.
The conversation that your users have with your Action will be relayed from their Assistant device (such as Google Home) to Google's servers, which do a little processing, and then to your server. Your server is then responsible for sending back a reply to Google's servers, which sends it on to the Assistant device. This is very similar to how a web browser and server work, and for good reason - your server accepts commands via a "webhook", which is just a fancy way of saying that Google's servers contact your server via HTTPS, and you're sending back a reply via HTTPS.
Your webhook can do anything - as long as it does it fast enough. You can store what command the person has issued and either aggregate a number of them into a file format to send, or send each one.
Your Action does not, itself, run on the user's device any more than a web page with a form "runs" on the user's device. It displays there, just like your Action is read out loud... but almost all interaction is sent back to you with minimal processing on the device itself.
First of all I'm not sure if this is the correct place to post this question, if its not please tell where should I post it.
My doubt is if I can use Dropbox to host images and then send emails linking that image to preview it , I don't want to send it as an attachment , but as an image in the email , is that possible ? Or do I have to upload it to a hosting?
This question was already replied here and I strongly agree with the accepted response: don't do it in production.
Dropbox imposes limits on bandwidth that you can confirm here and stated below, so I would say it's ok for internal testing only.
Dropbox Basic (free) accounts:
The total amount of traffic that all of your links and file requests
together can generate without getting banned is 20 GB per day. The
total number of downloads that all of your links together can generate
is 100,000 downloads per day.
If you don't have other option or still insist on doing it, just be sure you keep yourself under the limits in order to don't go against their terms of use and avoid being banned.
I have a web site with various graphs embedded in it that are generated externally. Occasionally those graphs will fail to generate and I would like to catch that when it happens. These graphs are embedded in multiple pages and I would rather not check each page manually. Is there any kind of tool or perhaps a browser addon that could periodically take screenshots of different URLs and email them in a single email? It would be sufficient to have scaled-down screenshots of full pages emailed maybe once a day to me, allowing me to take a quick glance and see that all the graphs are there and look okay.
I'm a big fan of automation. Rather than have emails generated that you then have to look at, take a look at 'replacing custom missing images in jquery'. This will run a piece of Javascript for each image that fails. Extending that to make a request to a URL that you control, which may also include the broken URL (or just the filename that is broken) would not be too hard. That URL would then generate an email, and store the broken URL so that it doesn't send 5000 emails if there's a flurry of hits to your page.
Another idea building on the above is to effectively change the external 404 from the source site to a local one (eg /backend/missing-images/) - the full-path need not exist - you are just generating a local 404 record in your apache logs. Logwatch will send a list of 404 pages from the apache log to you daily (or more often, if you want) by email.
While I haven't actually used it, an email analytics web app called Litmus claims to be able to track:
How long someone takes to read an email.
Whether it is forwarded.
Whether it is deleted.
Whether it is printed.
What email client was used to read it.
I'm curious about where it gets this information from. Most email clients i've seen don't even load external images without explicitly loading them, let alone javascript.
Even if a lot just support images, that wouldn't give away items 1-3.
Here's my best guess. As this link rockinthesixstring posted says, it relies on images but not javascript.
How long someone takes to read an email.
Place several images in the email that take a while to load, if the email is read for a long time, more are loaded.
Whether it is forwarded.
Is the image loaded from more than one IP/user agent?
Whether it is deleted.
The screenshots show this combined with glanced.
Whether it is printed.
Add a background image bug to a print stylesheet.
What email client was used to read it.
Check the user agent.
Any email analytics application I've seen use an image tracker. Basically if you attach a code generated 1x1 px image somewhere in the email, then during the loading of that image on the server side, you capture all of the ServerVariables
http://msdn.microsoft.com/en-us/library/ms524602%28VS.90%29.aspx
EDIT:
I just read some of the information on the Litmus website an it looks as though it confirms what I wrote above regarding image tracking
Most services offered online today that claim to "track" e-mails,But every one using image.
Is there any way to track the mail?
most of the mail servers blocking the images, after clicking the "download image" they show images,this is not exact tracking.(most of the peoples not like to download the images)
I'm searching other ways.
how this is work with out downloading image
img src="www.mysite.com/?promo=offer1">
You could request a read receipt, but again no guarantee of it being sent.
In short - no there is no way to track an email itself once it has left your local MTA.
If this is for a web promotion, the usual thing is to add a promo identifier to any links back to your website (e.g. "www.mysite.com/specialoffer1" or "www.mysite.com/?promo=offer1") so you can see who has visited as a result of receiving the email.