Fill the table with data for missing date (postgresql, redshift)

Question

I'm trying to fill daily data for missing dates and can not find an answer, please help.

My daily_table example:

      url          | timestamp_gmt | visitors | hits  | other.. 
-------------------+---------------+----------+-------+-------
 www.domain.com/1  | 2016-04-12    |   1231   | 23423 |
 www.domain.com/1  | 2016-04-13    |   1374   | 26482 |
 www.domain.com/1  | 2016-04-17    |   1262   | 21493 |
 www.domain.com/2  | 2016-05-09    |   2345   | 35471 |          

Expected result: I wand to fill this table with data for every domain and every day which just copy data from previous date:

      url          | timestamp_gmt | visitors | hits  | other.. 
-------------------+---------------+----------+-------+-------
 www.domain.com/1  | 2016-04-12    |   1231   | 23423 |
 www.domain.com/1  | 2016-04-13    |   1374   | 26482 |
 www.domain.com/1  | 2016-04-14    |   1374   | 26482 |     <-added
 www.domain.com/1  | 2016-04-15    |   1374   | 26482 |     <-added
 www.domain.com/1  | 2016-04-16    |   1374   | 26482 |     <-added
 www.domain.com/1  | 2016-04-17    |   1262   | 21493 |
 www.domain.com/2  | 2016-05-09    |   2345   | 35471 |          

I can move a part of the logic into php, but it is undesirable, because my table has billions of missing dates.

SUMMARY:

During a few last days I foud out that:

1. Amazon-redshift works with 8-th version of PostgreSql, that's why it does not support such a beautiful command like JOIN LATERAL
2. Redshift also does not support generate_series and CTEs
3. But it supports simple WITH (thank you @systemjack) but WITH RECURSIVE does not

Answer 1

Finally, I finished my task and I want to share some useful things.

Instead of generate_series I used this hook:

WITH date_range AS (
  SELECT trunc(current_date - (row_number() OVER ())) AS date
  FROM any_table  -- any of your table which has enough data
  LIMIT 365
) SELECT * FROM date_range;

To get list of URLs which I have to fill with the data I used this:

WITH url_list AS (
  SELECT
    url AS gapsed_url,
    MIN(timestamp_gmt) AS min_date,
    MAX(timestamp_gmt) AS max_date
  FROM daily_table
  WHERE url IN (
    SELECT url FROM daily_table GROUP BY url
    HAVING count(url) < (MAX(timestamp_gmt) - MIN(timestamp_gmt) + 1)
  )
  GROUP BY url
) SELECT * FROM url_list;

Then I combinet given data, let's call it url_mapping:

SELECT t1.*, t2.gapsed_url FROM date_range AS t1 CROSS JOIN url_list AS t2
WHERE t1.date <= t2.max_date AND t1.date >= t2.min_date;

And to get data by closest date I did the following:

SELECT sd.*
FROM url_mapping AS um JOIN daily_table AS sd
ON um.gapsed_url = sd.url AND (
  sd.timestamp_gmt = (SELECT max(timestamp_gmt) FROM daily_table WHERE url = sd.url AND timestamp_gmt <= um.date)
)

I hope it will help someone.