PHP / HTML form - show data on the same page in Docker container, does not print

Question

I want to have an HTML/PHP simple form on Apache. I would like the user to submit some data and then this data should be shown on the same page after submission. I want to have it all in a Docker container.

It might be the Docker issue, because it works on localhost.

I have PHP installed on my Ubuntu system. However, after submitting a form, I can't see the data I provided.

File index.html

<?php
$message = "";
if(isset($_POST['SubmitButton'])){ // Check if form was submitted
  $input = $_POST['inputText']; // Get input text
  $message = "Success! You entered: ".$input;
}
?>

<html>
<body>
<form action="" method="post">
<?php echo $message; ?>
  <input type="text" name="inputText"/>
  <input type="submit" name="SubmitButton"/>
</form>
</body>
</html>

Dockerfile

FROM webdevops/php:8.2

RUN apt update -y && apt upgrade -y
RUN apt install -y apache2
RUN apt install -y apache2-utils
RUN sudo a2enmod php8.2

WORKDIR /var/www/html
EXPOSE 80

COPY index.php /var/www/html/post
CMD ["apache2ctl", "-D", "FOREGROUND"]

Maybe you have some intermedia redirect that does not preserve data? — Justinas, Jul 02 '23 at 16:05
@Justinas I dont think so, because it works on localhost without any problems — Brian Brown, Jul 02 '23 at 17:10
Please make following: Open DevTools, in Network tab mark "reserve requests" and than submit form. Check what data is sent to back-end and what kind of requests are made. Update question with relevant information from Network tab — Justinas, Jul 03 '23 at 09:32
Are you sure this is a Docker problem? Would it work without docker? What have you tried to resolve the problem? Where are you stuck? — Nico Haase, Jul 03 '23 at 09:45
Have you added an ```echo``` statement to print the ```$message```? — Drk, Jul 06 '23 at 11:38
Using *.html* instead *.php* can't be the first time. What is the canonical duplicate question? — Peter Mortensen, Jul 23 '23 at 10:45

score 5 · Answer 1 · edited Jul 23 '23 at 10:44

5

Errors

PHP won't execute when the file name ends with .html. It should be index.php
You're using the PHP image of webdevops/php:8.2 which already has Apache and PHP.

As I know, these will not work:
```
RUN apt install -y apache2
RUN apt install -y apache2-utils
RUN sudo a2enmod php8.2
```
You're copying your file into a directory named post which doesn't exist and doesn't seem needed

Try this:

File index.php

<?php
$message = "";
if(isset($_POST['SubmitButton'])){ //check if form was submitted
  $input = $_POST['inputText']; //get input text
  $message = "Success! You entered: ".$input;
}
?>

<html>
<body>
<form action="" method="post">
<?php echo $message; ?>
  <input type="text" name="inputText"/>
  <input type="submit" name="SubmitButton"/>
</form>
</body>
</html>

Dockerfile

FROM webdevops/php-apache:8.2

WORKDIR /var/www/html
COPY index.php ./

EXPOSE 80
CMD ["supervisord"]

edited Jul 23 '23 at 10:44

Peter Mortensen

30,738
21
105
131

answered Jul 03 '23 at 09:39

Abdulla Nilam

36,589
17
64
85

`Cant connect to 127.0.0.1:7004` – Brian Brown Jul 07 '23 at 20:00
what is `127.0.0.1:7004`? from where `7004` comes from ? – Abdulla Nilam Jul 08 '23 at 05:29
Why [supervisord](http://supervisord.org/introduction.html)? What is it supposed to do? – Peter Mortensen Jul 23 '23 at 10:48
Possibly related: *[Alternative to supervisord for Docker](https://stackoverflow.com/questions/33850460/)* – Peter Mortensen Jul 23 '23 at 10:54

score -4 · Answer 2 · answered Jul 06 '23 at 08:51

-4

I see that in your form tag, the action attribute is empty (action=""). This will submit to the same URL it’s currently on.

Change it to action="index.php" to submit the form data to the PHP script.

answered Jul 06 '23 at 08:51

Sreeram Nair

2,369
12
27

Please add some more explanation to your answer such that others can learn from it. If this worked on localhost, but no longer when using Docker, what makes you think that your hint resolves the problem? Also, what makes you think that `index.php` exists after all? The OP hasn't shared any such file – Nico Haase Jul 06 '23 at 09:00
The docker file shared, says COPY index.php /var/www/html/post, so i think index.php is used – Sreeram Nair Jul 06 '23 at 09:05
Please add all clarification to your answer by editing it – Nico Haase Jul 06 '23 at 09:13
`index.php` will be the default page shown, so setting `action="index.php"` or leaving it blank wouldn't make any difference – DarkBee Jul 06 '23 at 09:27
1

Hi, Sreeram Nair. Most or all of your last 11 answers appear likely to be entirely or partially written by AI (e.g., ChatGPT). Many also have comments indicating that they are wrong in some respect. Please be aware that [posting AI-generated content is not allowed here](//meta.stackoverflow.com/q/421831). If you used an AI tool to assist with any answer, I would encourage you to delete it. We do hope you'll stick around and continue to be a valuable part of our community by posting *your own* quality content. Thanks! – NotTheDr01ds Jul 22 '23 at 22:31
**Readers should review this answer carefully and critically, as AI-generated information often contains fundamental errors and misinformation.** If you observe quality issues and/or have reason to believe that this answer was generated by AI, please leave feedback accordingly. – NotTheDr01ds Jul 22 '23 at 22:31

PHP / HTML form - show data on the same page in Docker container, does not print

File index.html

Dockerfile

2 Answers2

File index.php

Dockerfile