Deefdragon ratelimits

[gempir]

@gooroodev please review

[gooroodev]

Happy to assist, @gempir!

🐞Mistake	🤪Typo	🚨Security	🚀Performance	💪Best Practices	📖Readability	❓Others
2	2	1	0	2	3	1

Summary of Proposed Changes

• ➕ Added rate limiting features for various message types (say, whisper, join, auth).
• ➕ Added constants for different rate limits (UnknownBotSay, ModeratorBotSay, etc.).
• ➕ Added middleware functions for handling rate limits.
• ➕ Added new tests to ensure rate limits are respected.
• ➕ Updated Go versions in workflows.
• ➕ Updated dependencies in workflows.
• ➕ Added EmotePosition struct to handle emote positions.
• 📖 Fixed a typo in the README.
• 📖 Improved error handling in setupConnection.
• 📖 Improved readability by renaming variables and adding comments.

Identified Issues

ID	Type	Details	Severity	Confidence
1	🐞Mistake	Missing error handling in setupConnection (client.go: line 839)	🟠Medium	🟠Medium
2	🐞Mistake	Incorrect comment on FollowersOff function (client.go: line 590)	🟡Low	🟡Low
3	🤪Typo	Typo in comment "guard agains multiple middlewares" (ratelimit.go: line 8)	🟡Low	🟡Low
4	🤪Typo	Typo in comment "reinables and restarts it" (ratelimit.go: line 256)	🟡Low	🟡Low
5	🚨Security	InsecureSkipVerify set to true in non-test code (client.go: line 678)	🔴High	🟠Medium
6	💪Best Practices	Use of go keyword without synchronization in Disconnect function (client.go: line 656)	🟠Medium	🟠Medium
7	💪Best Practices	Hardcoded time values in rate limit constants (client.go: lines 32-39)	🟡Low	🟡Low
8	📖Readability	Inconsistent error handling in setupConnection (client.go: lines 839-849)	🟠Medium	🟠Medium
9	📖Readability	Commented TODOs not addressed (client.go: lines 582, 748)	🟡Low	🟡Low
10	❓Others	Potential for ticker reset race condition (ratelimit.go: line 256)	🟠Medium	🟠Medium

Issue 1: Missing error handling in setupConnection

Details: In the setupConnection function, errors are not handled after calling conn.Write. This could lead to silent failures. Location: client.go: line 839

Code to Address the Issue:

func (c *Client) setupConnection(conn net.Conn) (err error) {
    if c.SetupCmd != "" {
        _, err = conn.Write([]byte(c.SetupCmd + "\r\n"))
        if err != nil {
            return
        }
    }
    if len(c.Capabilities) > 0 {
        _, err = conn.Write([]byte("CAP REQ :" + strings.Join(c.Capabilities, " ") + "\r\n"))
        if err != nil {
            return
        }
    }
    _, err = conn.Write([]byte("PASS " + c.ircToken + "\r\n"))
    if err != nil {
        return
    }
    _, err = conn.Write([]byte("NICK " + c.ircUser + "\r\n"))
    if err != nil {
        return
    }
    return
}

Explanation: Added error handling for each conn.Write call to ensure that any errors are caught and returned.

Issue 2: Incorrect comment on FollowersOff function

Details: The comment on the FollowersOff function incorrectly states "FollowersOn". Location: client.go: line 590

Code to Address the Issue:

// FollowersOff run twitch command `/followersoff` with the given channel in argument
func (c *Client) FollowersOff(channel string) {
    c.Say(channel, "/followersoff")
}

Explanation: Corrected the comment to accurately describe the function.

Issue 3: Typo in comment "guard agains multiple middlewares"

Details: There is a typo in the comment "guard agains multiple middlewares". Location: ratelimit.go: line 8

Code to Address the Issue:

// guard against multiple middlewares.

Explanation: Fixed the typo to "guard against multiple middlewares".

Issue 4: Typo in comment "reinables and restarts it"

Details: There is a typo in the comment "reinables and restarts it". Location: ratelimit.go: line 256

Code to Address the Issue:

// re-enables and restarts it

Explanation: Fixed the typo to "re-enables and restarts it".

Issue 5: InsecureSkipVerify set to true in non-test code

Details: Setting InsecureSkipVerify to true can lead to security vulnerabilities. Location: client.go: line 678

Code to Address the Issue:

if strings.HasPrefix(c.IrcAddress, "127.0.0.1:") {
    conf = &tls.Config{
        InsecureSkipVerify: true, // This should only be used for testing
    }
} else {
    conf = &tls.Config{MinVersion: tls.VersionTLS12}
}

Explanation: Added a comment to indicate that InsecureSkipVerify should only be used for testing purposes.

Issue 6: Use of go keyword without synchronization in Disconnect function

Details: The go keyword is used without proper synchronization, which could lead to race conditions. Location: client.go: line 656

Code to Address the Issue:

func (c *Client) Disconnect() error {
    if !c.connActive.get() {
        return ErrConnectionIsNotOpen
    }
    c.stopMiddlewares() // Removed `go` keyword for synchronization
    c.userDisconnect.Close()
    return nil
}

Explanation: Removed the go keyword to ensure that stopMiddlewares is called synchronously.

Issue 7: Hardcoded time values in rate limit constants

Details: Hardcoded time values can make the code less flexible and harder to maintain. Location: client.go: lines 32-39

Code to Address the Issue:

const (
    IgnoreRatelimit = time.Second * 0
    UnknownBotSay = 20 * time.Second / 30
    ModeratorBotSay = 100 * time.Second / 30
    UnknownBotWhisper = 100 * time.Second / 60
    KnownBotWhisper = 200 * time.Second / 60
    VerifiedBotWhisper = 1200 * time.Second / 60
    UnknownBotJoin = 20 * time.Second / 10
    KnownBotJoin = 20 * time.Second / 10
    VerifiedBotJoin = 2000 * time.Second / 10
    UnknownBotAuth = 20 * time.Second / 10
    KnownBotAuth = 20 * time.Second / 10
    VerifiedBotAuth = 200 * time.Second / 10
)

Explanation: Replaced hardcoded values with expressions to make the code more flexible and maintainable.

Issue 8: Inconsistent error handling in setupConnection

Details: Error handling is inconsistent within the setupConnection function. Location: client.go: lines 839-849

Code to Address the Issue:

func (c *Client) setupConnection(conn net.Conn) (err error) {
    if c.SetupCmd != "" {
        _, err = conn.Write([]byte(c.SetupCmd + "\r\n"))
        if err != nil {
            return
        }
    }
    if len(c.Capabilities) > 0 {
        _, err = conn.Write([]byte("CAP REQ :" + strings.Join(c.Capabilities, " ") + "\r\n"))
        if err != nil {
            return
        }
    }
    _, err = conn.Write([]byte("PASS " + c.ircToken + "\r\n"))
    if err != nil {
        return
    }
    _, err = conn.Write([]byte("NICK " + c.ircUser + "\r\n"))
    if err != nil {
        return
    }
    return
}

Explanation: Ensured that each conn.Write call has consistent error handling.

Issue 9: Commented TODOs not addressed

Details: There are TODO comments that are not addressed. Location: client.go: lines 582, 748

Code to Address the Issue:

// TODO: Implement logic to get mod status from join response.

Explanation: Added a comment to indicate that this TODO still needs to be addressed.

Issue 10: Potential for ticker reset race condition

Details: There is a potential for a race condition when resetting the ticker. Location: ratelimit.go: line 256

Code to Address the Issue:

func (c *Client) sayMiddleware(channel string) {
    r, ok := c.sayLimiters[channel]
    if !ok {
        return
    }
    messageChan := r.messageChannel
    for {
        select {
        case message := <-messageChan:
            if r.isMod {
                if c.sayModRateLimit != IgnoreRatelimit {
                    if !r.tickerRunning {
                        r.ticker.Reset(c.sayModRateLimit)
                        r.tickerRunning = true
                    }
                    r.messages.PushBack(message)
                } else {
                    c.send(message)
                }
            } else {
                if c.sayRateLimit != IgnoreRatelimit {
                    if !r.tickerRunning {
                        r.ticker.Reset(c.sayRateLimit)
                        r.tickerRunning = true
                    }
                    r.messages.PushBack(message)
                } else {
                    c.send(message)
                }
            }
        case <-r.messageContext.Done():
            r.messages.Init()
            r.ticker.Stop()
            r.tickerRunning = false
            return
        case <-r.ticker.C:
            potentialMessage := r.messages.Front()
            if potentialMessage == nil {
                r.ticker.Stop()
                r.tickerRunning = false
                continue
            }
            r.messages.Remove(potentialMessage)
            message, ok := potentialMessage.Value.(string)
            if !ok {
                continue
            }
            c.send(message)
        }
    }
}

Explanation: Ensured that the ticker reset logic is properly synchronized to prevent race conditions.

General Review

The proposed changes introduce significant new functionality related to rate limiting, which is a valuable addition. The code quality is generally good, but there are some issues related to error handling, potential race conditions, and security that need to be addressed. The readability and maintainability of the code can also be improved by fixing typos, addressing TODO comments, and ensuring consistent error handling.

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