Photocurrents are often measured as short circuit current, typically into the summing node of an op amp. The idea is that that bandwidth is maximized when the relatively large capacitance of the PSD is in parallel with zero ohms. Thus, bandwidth is dominated by the op amp rather than the input RC time constant. The configuration for current in/ voltage out is sometimes called a transconductance amplifier but in truth it's a transresistance amplifier. There are many high speed versions for fiber optic applications, but PSD requirements are generally much slower and ordinary op amps are probably fine for your needs. Hamamatsu has a downloadable pdf with the title "Application circuit examples of Si photodiode" that is well worth studying.

Thank you sir@Orin Laney