PHP at Bloomberg's - 1

This is not a Bloomberg Web Services tutorial. It is a post how I use PHP to connect to Bloomberg Web Services.

Part one, setting up the environment. (This post.)

Recently I have created some web services clients importing data from cloud services. This has been very simple tasks, I just got a link to a REST service with a few parameters. Call the link and receive a JSON or XML response. Now the financial guys asked me to import currency rates from Bloomberg I recommended to use the SOAP web services from Bloomberg. Before I started I had to register at Bloomberg Customer Service Center to get access to documentation. I realised this was going to be more complicated than my previous web services clients, the Bloomberg SOAP protocol is complex I didn’t understand much of the voluminous documentation. I found a recommendation of using SoapUI to test and try Bloomberg’s web services. SoapUI turned out to be a great software, a must if you are new to Bloomberg web services. (There are other softwares similar to SoapUI.) Without SoapUI I would probably still be trying to figure out how to use the services and set up the complex parameters. Here you see part of a simple request:

With the help of SoapUI it was actually simple to setup and test requests. None of them worked so I started to create tickets at the service center, (the only way to get help from Bloomberg). I do not know if i was just unlucky or if I was not skilled enough to ask the right question but responses to my first ticket was far from good and slow. I had problems with the security certificate, when you access Bloomberg web services you need to authenticate yourself with a certificate. I installed the certificate wrongly, when you start installing the certificate you get this popup:

You should press save and store the certificate in a safe place, where the web services can access it.  (The Open button is a red herring that guides you through an installation process that ends with  ‘install was successful’, which led me to the faulty conclusion I had installed the certificate sucessfully.)
After I had sorted out the certificate issue, the web services started to respond that my request was in error. New tickets to the service center and now (I had more specific  questions) the service center responded promptly (often with an hour or two) after a while I could ask my first legal query.
This is how Bloomberg web services works. Send in a request and you receive a responseId, you then use this responseId to ask for the result of your request. A typical response looks like this (in SoapUI):
You then take the responseId and ask for the result of your request like this:

For me it normally takes 10 to 40 minutes before the result is ready for delivery.
I realised it would not be super simple to create, schedule and use Bloomberg Soap Web Services, instead of creating my web client in C# which I’m still far from comfortable with I decided to try PHP in Linux which I know much better.
I had to transfer my p12 access certificate (see above) to Linux. I did a binary FTP transfer to my Linux server, of course that did not work. This is how you should transfer the certificate to Linux and PHP. First to a normal ASCII transfer (I used FTP) then in a console session convert the p12 certificate to a pem certificate with this openssl command:
openssl pkcs12 -in Certificate.p12 -out Certificate.pem -clcerts
Now I’m ready to access Bloomberg web services from PHP/Linux.

In Windows you can start up a bash environment by firing off a Git console:
& 'C:\Program Files\Git\bin\sh.exe' --login
in Powershell and then run the openssl comand above.
If you do not have Git installed there are other opensll for Windows, Google around and download a version that suit you.

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