display posts of custom post type with custom taxonomy

Question

I have created a custom post type 'CPT_A' with CPT UI plugin. I have also created custom taxonomy 'Category_A' and 'Category_B' for 'CPT_A'. I have Posts 'Post_A', 'Post_B', 'Post_C', 'Post_D', 'Post_E' for 'CPT_A' and assigned 'Post_A', 'Post_B', 'Post_C' them to custom taxonomy 'Category_A' and 'Post_D', 'Post_E' to category 'Category_B'.

I have created archive page 'archive-CPT_A.php' to display all posts of 'CPT_A' post type. and WP archive.php handles posts listings for all Categories of the 'CPT_A' Posts. And there is 'single-CPT_A.php' to display contents of single 'CPT_A' Post.

Now, What I am trying to do is I have created a sidebar and trying to display related posts of 'CPT_A' in sidebar. If the post is from 'Category_A' it should display other posts from same category and if the post is from 'Category_B' it should display other posts from 'Category_B' So I used this code:

<?php
    $cats = get_terms('CPT_A');

    $args = array(
        'post_type' => 'CPT_A',
        'post__not_in' => array( get_the_ID() ),
        'posts_per_page' => 5,
        'cat'     => $cats[0]->term_id,
    );
    $query = new WP_Query( $args );

?>  

<?php if( $query->have_posts() ) : while( $query->have_posts() ) : $query->the_post(); ?>   

<li>
    <a href="<?php the_permalink(); ?>"><?php the_title(); ?></a>
</li>

<?php endwhile; endif; wp_reset_postdata(); ?> 

But it's displaying hiding current post from list (which is correct) but also displaying other posts from 'Category_B' too. After some research I tried this code:

<?php

    $cats = get_terms('tour_category');

    $args = array(
        'post_type' => 'tour_package',
        'post__not_in' => array( get_the_ID() ),
        'posts_per_page' => 5,
        'cat'     => $cats[0]->term_id,
        'tax_query' => array(
            array(
                'taxonomy' => 'tour_category',
                'field' => 'slug',
                'terms' => $custom_term->slug,
            )
            )
    );
    $query = new WP_Query( $args );

?>  

<?php if( $query->have_posts() ) : while( $query->have_posts() ) : $query->the_post(); ?>   

<li>
    <a href="<?php the_permalink(); ?>"><?php the_title(); ?></a>
</li>

<?php endwhile; endif; wp_reset_postdata(); ?>

But it's displaying nothing for me.

What is the best way to do this? I didn't find any suitable tutorial for me so posting this question here.

Answer 1

I would use "get_the_terms" to get the terms related to the post instead of "get_terms", here is a quick suggestion (not tested)

    $args=array(  
        'post_type'=>'tour_package',                 
        'post__not_in' => array(get_the_ID()),
        'posts_per_page'=> 5, 
        'caller_get_posts'=>1,//handle sticky post but not in first
    ); 

    $categories = get_the_terms( get_the_ID(),'tour_category' );

    if ($categories)
            {   
                $category_ids = array();         
                foreach($categories as $individual_category){
                   $category_ids[] = $individual_category->term_id; 
                }
                if(!empty($category_ids))
                {

                    $args['tax_query']= array(
                        array(
                            'taxonomy' => 'tour_category',
                            'field'    => 'term_id',
                            'terms'    => $category_ids,
                        ),
                    );
                }
            }
$query = new WP_Query( $args );