Up to now we've dealt with and configured in genetics to serve static files of various types leaving
the rendering of that file to be handled by the client or browser based on its content type or MIME
type.
Now while serving static files is great a critical part of most web servers is the ability to serve
dynamic content that's been generated from a server side language such as P. HP.
If you recall from the first section of this course I mentioned that engine X isn't able to embed its
server side language processors so instead then we'll configure a standalone BHB service namely p p
if P. M. to which engine X will pass the request for processing and then upon receiving the response
typically has h.t. amelle return there to the client.
This is essentially engine X functioning as a reverse proxy server.
One of the strong points but we'll dig into that specific topic later on in the course.
Step one then is to actually install the page b f P. M. service.
We can safely use our package manager to do this.
So again UPDATE AP t..
Just good practice.
And once that's done run apt get install the HP F. P. M. which will install the latest stable release
of BHP fbm available to a peaty which we can see here happens to be BHB seven point one confirm.
Fast forward through this and all done now.
As with most services we install using a p t p s p f P. M. is very conveniently already configured as
a system D service.
Same as we've done for engine X which we can see happened year as Patch B seven point one dash F. P.
M..
Not just pitch b f be m as we installed it.
This version number being a common naming convention of BHB just in order to have multiple versions
in use at once.
Should that be a requirement for development or testing.
We can confirm that the service exists by listing all the system D services system C T L list units
filtering the results with grep for anything containing be and there we have it.
As expect it be B seven point one f P. M..
Check the status of our newbie HP Service System C T L status.
B seven point one dash F be M which is already running a single master process and two workers.
So with B F be m running and ready to process page B requests Let's head over to engine next hour conf
and configure the passing of our appear to be files to this service.
First addition to this file is the inclusion of the index directive.
This being a standard directive which tells engine X which file to load if the request point to a directory
the default so the current value being indexed to HD moul.
Hence why when we request our domain slash indexed or HDMI loads route Plus this index value.
This like the try files.
DirecTV can take multiple arguments in order of importance.
So with the inclusion of BHB we'll typically want to serve index Dogpatch P first if it exists in a
directory and if not.
Secondly look for indexed or h.t. amelle the default.
This by no means being a hard and fast rule but the most likely configuration when dealing with a to
be based project.
Next I'll get rid of this location create a new one for Slash So a prefix match for anything in which
we're going to try it with try files the request that you are by then.
Alternatively the requested you are I with an add a trailing slash in case it maps to a directory with
either indexed of BHB or indexed dot aged here Mel.
And finally if none of these exist go back to the default engine next foro for which we can write with
equals forro for.
So this location will take care of any requests for static content.
Meaning that in a second location block using a regular expression match so it will take priority over
this prefix match.
We can match anything ending in dot BHB like so in order to pass a 2p edge.
P if P. M..
Which will do.
By means of the fast CGI protocol.
If you're not familiar with fast CGI I've linked to some information in the list and resources but essentially
it's a protocol like HTP for transferring binary data.
You don't need to understand this but just know that it's how engine X will communicate with B.
B F p. m..
We could have done this using the standard htb Protocol also.
But fast CGI is slightly faster before we pass requests in this location context to be a.
B f be m however we still need to include some other configuration parameters.
Luckily as with our MIME types.
Engine X provides a very good include with fast g.g. I preconfigured you might have spotted it during
the installation but to double check.
It's located at slash ATC slash engine X fast CGI dot conf.
So in the same directory as the engine start con file meaning we can again just reference it relative
to this file fast CGI dot conf then to pass this request to be a b f P. M. using fast e.g. I say FAST
C I underscore pass and what we want to pass this to is a Unix socket created by page pfb M..
Think of a socket as an HTP port a file on which a service can listen for binary data.
Hence the use of fast CGI as a protocol.
Again understanding the fast CGI protocol and Unix sockets is by no means required for understanding
how to configure BHB within generics.
But it's good to at least get an overall understanding of what's happening and why it's done like this
to indicate that this endpoint is a Unix socket.
Then we can say Unix colon and the location of that socket.
In this case it's going to be located at slash run slash BHB slash BHB seven point one dash.
If B M dot soc.
I'll show you how to find the socket location for your install in a second.
Save this over to the terminal and before we reload this engine XT configuration we can make sure the
HP fbm socket is in fact at that location.
By searching for it I'll use the find command.
Look in the root of this machine.
So searching everything by name and we'll search for any thing ending worth F be M dot shock enter and
found at that exact location.
As I've configured engine X so knowing that's correct reload engine X configuration.
We still don't have any BHB files to test this worth so we'll create a simple test file.
Just write the contents directly to our new page B file.
Make it BHB opening statement calling BHB info close BHB to slash sites slash demo slash info Dogpatch
be.
If you're not familiar with BHB this is just saying start processing the content as patch.
Be here call the BHB info function which is a native P P function for displaying all of page piece configuration
information and stop processing BHB which wasn't really necessary as the file ends here.
Anyway it over to the browser so we can test this.
I'll just reload the demesne without any path and we get that same indexed to htl page from the demo
directory.
This of course being as we've named the BHB file info dot BHP meaning on this root directory request
engineer is first checking for indexed or HP which isn't found then for indexed or HDL and serving the
old demo page.
This request also not containing a BHB extension.
Hence not being matched on the BHB location.
Change this request for info Dogpatch.
However meaning will match on the BHB location and we get this error 5 0 too bad gateway.
This being a prime example of when engine x error logs can really help out check the very last entry
of the error log with tail and N flag one meaning one line of the end of this file var log.
Engine x error log critical error connecting to Unix socket slash run slash B.
B B.
B seven point one.
If B em sock with the reason engine x cannot connect to the socket being permission denied.
A very common situation in this case.
We can very quickly find the reason for this permissions error by checking the user with which the engine
XT process is running the worker process here.
Nobody which is the default for change and X and the p p if P. M. process w w w dashed data.
Meaning this nobody user does not have permission to appear to be fbm socket.
There is of course a number of ways we can solve this including changing the permissions of the socket.
But the most secure and easiest way by far is to configure engine X to run as the same user w w w dash
data in the configuration file.
Simply add in the main context user w w w dashed data safe.
Reload engine x.
Check that process again which is now correctly running as w w w desch Data reload info Dogpatch.
Be in the browser and it works.
We get that full output of the BHB info function meaning engine X received the request matched it on
the BHB location past that to the pier.
B if B MS service where it was processed and passed back to engine X which in turn then served that
processed response to us.
One last point to cover is this index directive with indexed or appear to be as the priority.
Let's create an index stoppage be file in that demo directory again.
I'll write some content directly to at Echo a h one date.
Then as beatch be echo the date function with a format of day of the week L..
Day of the month.
J.
Capital S and month.
F.
End p.
P processing.
And close that each one statement.
Writing there to slash sites.
Slash demo slash indexed iph be back in the browser.
Remove the request path.
So previously serving indexed old h.t. a email and we get that indexed iph page instead.
Meaning this indexed directive prioritized.
Oh a new page B page over there h.t. a mail one that wraps up the basics of configuring a server side
language process for INJ annexe.
But be sure to check out all the links in the lesson and resources for more advanced configurations
and implementations.