How to set the input of a Keras layer with a Tensorflow tensor?

Question

In my previous question, I used Keras' Layer.set_input() to connect my Tensorflow pre-processing output tensor to my Keras model's input. However, this method has been removed after Keras version 1.1.1.

How can I achieve this in newer Keras versions?

Example:

# Tensorflow pre-processing
raw_input = tf.placeholder(tf.string)
### some TF operations on raw_input ###
tf_embedding_input = ...    # pre-processing output tensor

# Keras model
model = Sequential()
e = Embedding(max_features, 128, input_length=maxlen)

### THIS DOESN'T WORK ANYMORE ###
e.set_input(tf_embedding_input)
################################

model.add(e)
model.add(LSTM(128, activation='sigmoid'))
model.add(Dense(num_classes, activation='softmax'))

Answer 1

After you are done with pre-processing, You can add the tensor as input layer by calling tensor param of Input

So in your case:

tf_embedding_input = ...    # pre-processing output tensor

# Keras model
model = Sequential()
model.add(Input(tensor=tf_embedding_input)) 
model.add(Embedding(max_features, 128, input_length=maxlen))