\[ \boxed { {\frac {{\rm d}^{2}}{{\rm d}{x}^{2}}}y \left ( x \right ) +y \left ( x \right ) {\frac {\rm d}{{\rm d}x}}y \left ( x \right ) - \left ( y \left ( x \right ) \right ) ^{3}- \left ( {\frac {{\frac {\rm d}{{\rm d}x}}f \left ( x \right ) }{f \left ( x \right ) }}+f \left ( x \right ) \right ) \left ( 3\,{\frac {\rm d}{{\rm d}x}}y \left ( x \right ) + \left ( y \left ( x \right ) \right ) ^{2} \right ) + \left ( a \left ( f \left ( x \right ) \right ) ^{2}+3\,{\frac {\rm d}{{\rm d}x}}f \left ( x \right ) +3\,{\frac { \left ( {\frac {\rm d}{{\rm d}x}}f \left ( x \right ) \right ) ^{2}}{ \left ( f \left ( x \right ) \right ) ^{2}}}-{\frac {{\frac {{\rm d}^{2}}{{\rm d}{x}^{2}}}f \left ( x \right ) }{f \left ( x \right ) }} \right ) y \left ( x \right ) +b \left ( f \left ( x \right ) \right ) ^{3}=0} \]
Mathematica: cpu = 1.426181 (sec), leaf count = 93 \[ \text {DSolve}\left [y(x) \left (a f(x)^2-\frac {f''(x)}{f(x)}+3 f'(x)+\frac {3 f'(x)^2}{f(x)^2}\right )+b f(x)^3-\left (\frac {f'(x)}{f(x)}+f(x)\right ) \left (3 y'(x)+y(x)^2\right )+y''(x)+y(x) y'(x)-y(x)^3=0,y(x),x\right ] \]
Maple: cpu = 1.263 (sec), leaf count = 135 \[ \left \{ y \left ( x \right ) ={\it ODESolStruc} \left ( f \left ( {\it RootOf} \left ( \int \!{\it \_b} \left ( {\it \_a} \right ) \,{\rm d}{ \it \_a}+{\it \_C1}-\int ^{{\it \_Z}}\!f \left ( {\it \_f} \right ) {d{ \it \_f}} \right ) \right ) {\it \_a},[ \left \{ {\frac {\rm d}{{\rm d}{ \it \_a}}}{\it \_b} \left ( {\it \_a} \right ) = \left ( -{{\it \_a}}^{3} -{{\it \_a}}^{2}+a{\it \_a}+b \right ) \left ( {\it \_b} \left ( {\it \_a} \right ) \right ) ^{3}+ \left ( {\it \_a}-3 \right ) \left ( {\it \_b} \left ( {\it \_a} \right ) \right ) ^{2} \right \} , \left \{ {\it \_a}={\frac {y \left ( x \right ) }{f \left ( x \right ) }},{\it \_b} \left ( {\it \_a} \right ) =-{\frac { \left ( f \left ( x \right ) \right ) ^{3}}{ \left ( {\frac {\rm d}{{\rm d}x}}f \left ( x \right ) \right ) y \left ( x \right ) -f \left ( x \right ) {\frac {\rm d}{{\rm d} x}}y \left ( x \right ) }} \right \} , \left \{ x={\it RootOf} \left ( \int \!{\it \_b} \left ( {\it \_a} \right ) \,{\rm d}{\it \_a}+{\it \_C1 }-\int ^{{\it \_Z}}\!f \left ( {\it \_f} \right ) {d{\it \_f}} \right ) , y \left ( x \right ) =f \left ( {\it RootOf} \left ( \int \!{\it \_b} \left ( {\it \_a} \right ) \,{\rm d}{\it \_a}+{\it \_C1}-\int ^{{\it \_Z}}\!f \left ( {\it \_f} \right ) {d{\it \_f}} \right ) \right ) {\it \_a} \right \} ] \right ) \right \} \]