Appearance
DeepSeek API完全指南
DeepSeek以其卓越的性价比和强大的代码能力,成为国产AI的明星产品
概述
DeepSeek是国产大模型的杰出代表,以其极高的性价比、强大的代码能力和推理能力著称。本教程将带你全面掌握DeepSeek API的使用方法。
为什么选择DeepSeek?
| 优势 | 说明 |
|---|---|
| 超高性价比 | 价格仅为GPT-4的1/100 |
| 代码能力强 | 代码生成和理解能力优秀 |
| 推理能力 | 复杂推理任务表现出色 |
| 国产合规 | 符合国内数据安全法规 |
DeepSeek模型概览
DeepSeek模型家族:
DeepSeek V3系列(最新)
├── deepseek-chat # 通用对话模型
└── deepseek-reasoner # 推理专用模型
DeepSeek V2系列(经典)
├── deepseek-v2.5 # 平衡版本
└── deepseek-coder-v2 # 代码专用模型
DeepSeek R1系列(推理)
└── deepseek-r1 # 强化学习推理模型基本概念
API Key
php
<?php
// 在DeepSeek官网获取API Key
// https://platform.deepseek.com/
// API Key格式
// sk-xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
$apiKey = getenv('DEEPSEEK_API_KEY');兼容性
DeepSeek API完全兼容OpenAI API格式:
php
<?php
// DeepSeek API使用与OpenAI相同的接口格式
// 只需更改base_url即可
$baseUrl = 'https://api.deepseek.com';环境准备
创建DeepSeek客户端
php
<?php
require 'vendor/autoload.php';
use GuzzleHttp\Client;
use GuzzleHttp\Exception\RequestException;
class DeepSeekClient
{
private $client;
private $apiKey;
private $baseUrl = 'https://api.deepseek.com';
public function __construct(string $apiKey)
{
$this->apiKey = $apiKey;
$this->client = new Client([
'base_uri' => $this->baseUrl,
'timeout' => 120,
'headers' => [
'Authorization' => 'Bearer ' . $this->apiKey,
'Content-Type' => 'application/json',
],
]);
}
public function chat(
array $messages,
string $model = 'deepseek-chat',
array $options = []
): array {
$params = [
'model' => $model,
'messages' => $messages,
];
if (isset($options['temperature'])) {
$params['temperature'] = $options['temperature'];
}
if (isset($options['max_tokens'])) {
$params['max_tokens'] = $options['max_tokens'];
}
if (isset($options['top_p'])) {
$params['top_p'] = $options['top_p'];
}
try {
$response = $this->client->post('/v1/chat/completions', [
'json' => $params,
]);
return json_decode($response->getBody(), true);
} catch (RequestException $e) {
$errorBody = $e->getResponse() ? $e->getResponse()->getBody()->getContents() : 'Unknown error';
throw new Exception('DeepSeek API Error: ' . $errorBody);
}
}
}
// 使用示例
$apiKey = getenv('DEEPSEEK_API_KEY');
$client = new DeepSeekClient($apiKey);
$result = $client->chat([
['role' => 'user', 'content' => '请用一句话介绍PHP语言']
]);
echo $result['choices'][0]['message']['content'];运行结果:
PHP是一种开源的服务器端脚本语言,特别适合Web开发,可以嵌入HTML中执行。推理模型使用
使用DeepSeek R1进行复杂推理
php
<?php
class DeepSeekReasoner
{
private DeepSeekClient $client;
public function __construct(DeepSeekClient $client)
{
$this->client = $client;
}
public function reason(string $problem): array
{
$result = $this->client->chat(
[
['role' => 'user', 'content' => $problem]
],
'deepseek-reasoner'
);
return [
'reasoning' => $result['choices'][0]['message']['reasoning_content'] ?? '',
'answer' => $result['choices'][0]['message']['content'],
];
}
public function solveMathProblem(string $problem): string
{
$result = $this->client->chat(
[
[
'role' => 'system',
'content' => '你是一个数学问题解决专家,请一步步推理并给出答案。'
],
['role' => 'user', 'content' => $problem]
],
'deepseek-reasoner'
);
return $result['choices'][0]['message']['content'];
}
public function analyzeCode(string $code): string
{
$result = $this->client->chat(
[
[
'role' => 'user',
'content' => "请分析以下代码的时间复杂度和空间复杂度,并给出优化建议:\n```\n{$code}\n```"
]
],
'deepseek-reasoner'
);
return $result['choices'][0]['message']['content'];
}
}
// 使用示例
$reasoner = new DeepSeekReasoner($client);
$result = $reasoner->reason('一个房间里有3盏灯,门外有3个开关,每个开关对应一盏灯。你只能进入房间一次,如何确定每个开关对应哪盏灯?');
echo "推理过程:\n" . $result['reasoning'] . "\n\n";
echo "答案:\n" . $result['answer'];高级参数配置
完整参数示例
php
<?php
class DeepSeekClient
{
// ... 前面的代码 ...
public function chatAdvanced(
array $messages,
string $model = 'deepseek-chat',
array $options = []
): array {
$params = [
'model' => $model,
'messages' => $messages,
];
$optionalParams = [
'temperature',
'max_tokens',
'top_p',
'stop',
'frequency_penalty',
'presence_penalty',
];
foreach ($optionalParams as $param) {
if (isset($options[$param])) {
$params[$param] = $options[$param];
}
}
try {
$response = $this->client->post('/v1/chat/completions', [
'json' => $params,
]);
return json_decode($response->getBody(), true);
} catch (RequestException $e) {
$errorBody = $e->getResponse() ? $e->getResponse()->getBody()->getContents() : 'Unknown error';
throw new Exception('DeepSeek API Error: ' . $errorBody);
}
}
}
// 使用示例
$result = $client->chatAdvanced(
[['role' => 'user', 'content' => '写一首关于程序员的诗']],
'deepseek-chat',
[
'temperature' => 0.8,
'max_tokens' => 500,
]
);参数详解
| 参数 | 范围 | 默认值 | 说明 |
|---|---|---|---|
| temperature | 0-2 | 1 | 控制随机性 |
| max_tokens | 1-模型上限 | 4096 | 最大输出Token |
| top_p | 0-1 | 1 | 核采样参数 |
| stop | 字符串或数组 | - | 停止序列 |
| frequency_penalty | 0-2 | 0 | 频率惩罚 |
| presence_penalty | 0-2 | 0 | 存在惩罚 |
流式响应处理
php
<?php
class DeepSeekClient
{
// ... 前面的代码 ...
public function chatStream(
array $messages,
string $model = 'deepseek-chat'
): Generator {
$response = $this->client->post('/v1/chat/completions', [
'json' => [
'model' => $model,
'messages' => $messages,
'stream' => true,
],
'stream' => true,
]);
$body = $response->getBody();
$buffer = '';
while (!$body->eof()) {
$chunk = $body->read(1024);
$buffer .= $chunk;
while (($pos = strpos($buffer, "\n")) !== false) {
$line = substr($buffer, 0, $pos);
$buffer = substr($buffer, $pos + 1);
$line = trim($line);
if (empty($line) || $line === 'data: [DONE]') {
continue;
}
if (strpos($line, 'data: ') === 0) {
$json = substr($line, 6);
$data = json_decode($json, true);
if (isset($data['choices'][0]['delta']['content'])) {
yield $data['choices'][0]['delta']['content'];
}
}
}
}
}
}
// 使用示例
echo "DeepSeek回复:";
foreach ($client->chatStream([['role' => 'user', 'content' => '讲一个程序员笑话']]) as $chunk) {
echo $chunk;
flush();
}多轮对话实现
php
<?php
class DeepSeekChatSession
{
private DeepSeekClient $client;
private array $messages = [];
private string $model;
public function __construct(DeepSeekClient $client, string $model = 'deepseek-chat')
{
$this->client = $client;
$this->model = $model;
}
public function setSystemPrompt(string $prompt): void
{
$this->messages = [
['role' => 'system', 'content' => $prompt]
];
}
public function chat(string $userMessage): string
{
$this->messages[] = ['role' => 'user', 'content' => $userMessage];
$response = $this->client->chat($this->messages, $this->model);
$assistantMessage = $response['choices'][0]['message']['content'];
$this->messages[] = ['role' => 'assistant', 'content' => $assistantMessage];
return $assistantMessage;
}
public function getHistory(): array
{
return $this->messages;
}
public function clearHistory(): void
{
$systemMessage = $this->messages[0] ?? null;
$this->messages = $systemMessage ? [$systemMessage] : [];
}
}
// 使用示例
$session = new DeepSeekChatSession($client);
$session->setSystemPrompt('你是一个专业的PHP开发工程师,用简洁的语言回答问题。');
echo "用户:PHP有哪些优点?\n";
echo "DeepSeek:" . $session->chat('PHP有哪些优点?') . "\n";常见错误与踩坑点
错误1:模型名称错误
php
<?php
// ❌ 错误做法:使用不存在的模型
$result = $client->chat($messages, 'deepseek-v3');
// ✅ 正确做法:使用正确的模型名称
$result = $client->chat($messages, 'deepseek-chat');
$result = $client->chat($messages, 'deepseek-reasoner');错误2:忽略推理模型的特殊输出
php
<?php
// ❌ 错误做法:只获取content
$result = $client->chat($messages, 'deepseek-reasoner');
echo $result['choices'][0]['message']['content'];
// ✅ 正确做法:同时获取推理过程
$result = $client->chat($messages, 'deepseek-reasoner');
if (isset($result['choices'][0]['message']['reasoning_content'])) {
echo "推理过程:\n" . $result['choices'][0]['message']['reasoning_content'] . "\n\n";
}
echo "答案:\n" . $result['choices'][0]['message']['content'];错误3:忽略余额不足
php
<?php
// ❌ 错误做法:不检查余额
$result = $client->chat($messages);
// ✅ 正确做法:处理余额不足错误
try {
$result = $client->chat($messages);
} catch (Exception $e) {
if (strpos($e->getMessage(), 'insufficient_balance') !== false) {
echo '账户余额不足,请充值后继续使用';
}
}常见应用场景
场景1:代码生成助手
php
<?php
class DeepSeekCodeAssistant
{
private DeepSeekClient $client;
public function generateCode(string $description, string $language = 'PHP'): string
{
$result = $this->client->chat([
[
'role' => 'system',
'content' => '你是一个专业的程序员,请生成简洁、高效的代码。'
],
[
'role' => 'user',
'content' => "请生成{$language}代码:{$description}"
]
]);
return $result['choices'][0]['message']['content'];
}
public function explainCode(string $code): string
{
$result = $this->client->chat([
[
'role' => 'user',
'content' => "请解释以下代码的功能:\n```\n{$code}\n```"
]
]);
return $result['choices'][0]['message']['content'];
}
public function debugCode(string $code, string $error): string
{
$result = $this->client->chat([
[
'role' => 'user',
'content' => "以下代码出错,请帮我修复:\n代码:\n```\n{$code}\n```\n错误信息:{$error}"
]
]);
return $result['choices'][0]['message']['content'];
}
}场景2:数学问题求解
php
<?php
class MathProblemSolver
{
private DeepSeekClient $client;
public function solve(string $problem): array
{
$result = $this->client->chat(
[
[
'role' => 'system',
'content' => '你是一个数学专家,请详细推理并给出答案。'
],
['role' => 'user', 'content' => $problem]
],
'deepseek-reasoner'
);
return [
'reasoning' => $result['choices'][0]['message']['reasoning_content'] ?? '',
'answer' => $result['choices'][0]['message']['content'],
];
}
}场景3:文档问答
php
<?php
class DocumentQA
{
private DeepSeekClient $client;
private string $document;
public function __construct(DeepSeekClient $client, string $document)
{
$this->client = $client;
$this->document = $document;
}
public function ask(string $question): string
{
$result = $this->client->chat([
[
'role' => 'system',
'content' => '你是一个文档问答助手,请根据提供的文档内容回答问题。'
],
[
'role' => 'user',
'content' => "文档内容:\n{$this->document}\n\n问题:{$question}"
]
]);
return $result['choices'][0]['message']['content'];
}
}场景4:内容创作
php
<?php
class ContentCreator
{
private DeepSeekClient $client;
public function generateArticle(string $topic, int $wordCount = 800): string
{
$result = $this->client->chat([
[
'role' => 'user',
'content' => "请写一篇关于{$topic}的文章,字数约{$wordCount}字。"
]
]);
return $result['choices'][0]['message']['content'];
}
public function generateSummary(string $content, int $maxLength = 200): string
{
$result = $this->client->chat([
[
'role' => 'user',
'content' => "请将以下内容总结为不超过{$maxLength}字:\n\n{$content}"
]
]);
return $result['choices'][0]['message']['content'];
}
}场景5:智能客服
php
<?php
class CustomerServiceBot
{
private DeepSeekClient $client;
private array $knowledgeBase = [];
public function addKnowledge(string $category, string $content): void
{
$this->knowledgeBase[$category] = $content;
}
public function handleQuery(string $query): string
{
$context = '';
foreach ($this->knowledgeBase as $category => $content) {
$context .= "【{$category}】\n{$content}\n\n";
}
$result = $this->client->chat([
[
'role' => 'system',
'content' => '你是一个友好的客服助手。请根据知识库回答问题,如果不知道答案,请诚实说明。'
],
[
'role' => 'user',
'content' => "知识库:\n{$context}\n\n客户问题:{$query}"
]
]);
return $result['choices'][0]['message']['content'];
}
}企业级进阶应用场景
场景1:构建智能代码审查系统
php
<?php
class CodeReviewSystem
{
private DeepSeekClient $client;
public function review(string $code, string $language = 'PHP'): array
{
$result = $this->client->chat([
[
'role' => 'system',
'content' => '你是一位资深代码审查专家。请从代码质量、安全性、性能三个维度审查代码。'
],
[
'role' => 'user',
'content' => "请审查以下{$language}代码,以JSON格式返回结果:\n```\n{$code}\n```"
]
]);
return json_decode($result['choices'][0]['message']['content'], true);
}
}场景2:构建复杂问题推理系统
php
<?php
class ComplexReasoningSystem
{
private DeepSeekClient $client;
public function analyze(string $problem): array
{
$result = $this->client->chat(
[
[
'role' => 'system',
'content' => '你是一个分析专家,请详细推理并给出结论。'
],
['role' => 'user', 'content' => $problem]
],
'deepseek-reasoner'
);
return [
'reasoning' => $result['choices'][0]['message']['reasoning_content'] ?? '',
'conclusion' => $result['choices'][0]['message']['content'],
'usage' => $result['usage'],
];
}
}常见问题答疑(FAQ)
Q1:DeepSeek的定价如何?
回答:
| 模型 | 输入价格 | 输出价格 | 相对GPT-4 |
|---|---|---|---|
| deepseek-chat | ¥1/百万Token | ¥2/百万Token | 约1/100 |
| deepseek-reasoner | ¥4/百万Token | ¥16/百万Token | 约1/20 |
Q2:deepseek-chat和deepseek-reasoner如何选择?
回答:
| 场景 | 推荐模型 | 原因 |
|---|---|---|
| 日常对话 | deepseek-chat | 速度快,成本低 |
| 代码生成 | deepseek-chat | 代码能力强 |
| 复杂推理 | deepseek-reasoner | 推理能力强 |
| 数学问题 | deepseek-reasoner | 逐步推理 |
Q3:如何处理API错误?
回答:
php
<?php
function handleDeepSeekError(Exception $e): string
{
$message = $e->getMessage();
if (strpos($message, 'invalid_api_key') !== false) {
return 'API Key无效';
}
if (strpos($message, 'insufficient_balance') !== false) {
return '账户余额不足';
}
if (strpos($message, 'rate_limit') !== false) {
return '请求过于频繁';
}
return '服务暂时不可用';
}Q4:如何获取推理过程?
回答:
php
<?php
$result = $client->chat($messages, 'deepseek-reasoner');
// 推理过程
$reasoning = $result['choices'][0]['message']['reasoning_content'] ?? '';
// 最终答案
$answer = $result['choices'][0]['message']['content'];Q5:如何优化Token使用?
回答:
php
<?php
// 1. 使用deepseek-chat进行简单任务
$result = $client->chat($messages, 'deepseek-chat');
// 2. 限制max_tokens
$result = $client->chat($messages, 'deepseek-chat', ['max_tokens' => 500]);
// 3. 使用简洁的提示
$prompt = "用50字解释:{$topic}";Q6:DeepSeek支持哪些功能?
回答:
| 功能 | 支持 | 说明 |
|---|---|---|
| 文本生成 | ✅ | 支持各种文本生成任务 |
| 代码生成 | ✅ | 代码能力强 |
| 流式输出 | ✅ | 支持流式响应 |
| 推理模式 | ✅ | deepseek-reasoner |
| 函数调用 | ✅ | 支持Function Calling |
| 多模态 | ❌ | 暂不支持 |
实战练习
基础练习
练习1:编写一个简单的DeepSeek聊天程序。
参考代码:
php
<?php
$apiKey = getenv('DEEPSEEK_API_KEY');
$client = new DeepSeekClient($apiKey);
echo "DeepSeek聊天助手 (输入 'quit' 退出)\n";
while (true) {
echo "\n你: ";
$input = trim(fgets(STDIN));
if ($input === 'quit') {
break;
}
$result = $client->chat([['role' => 'user', 'content' => $input]]);
echo "DeepSeek: " . $result['choices'][0]['message']['content'] . "\n";
}进阶练习
练习2:实现一个代码生成器。
参考代码:
php
<?php
class CodeGenerator
{
private DeepSeekClient $client;
public function generate(string $description, string $language = 'PHP'): string
{
$result = $this->client->chat([
[
'role' => 'system',
'content' => '你是一个代码生成专家,只输出代码,不要解释。'
],
[
'role' => 'user',
'content' => "生成{$language}代码:{$description}"
]
]);
return $result['choices'][0]['message']['content'];
}
}挑战练习
练习3:构建一个智能问题解答系统。
参考代码:
php
<?php
class IntelligentQA
{
private DeepSeekClient $client;
public function answer(string $question): array
{
$result = $this->client->chat(
[
['role' => 'user', 'content' => $question]
],
'deepseek-reasoner'
);
return [
'reasoning' => $result['choices'][0]['message']['reasoning_content'] ?? '',
'answer' => $result['choices'][0]['message']['content'],
];
}
}知识点总结
核心要点
- 超高性价比:价格仅为GPT-4的1/100
- API兼容:完全兼容OpenAI API格式
- 推理能力:deepseek-reasoner提供强大的推理能力
- 代码能力:代码生成和理解能力优秀
- 国产合规:符合国内数据安全法规
易错点回顾
| 易错点 | 正确做法 |
|---|---|
| 模型名称错误 | 使用deepseek-chat或deepseek-reasoner |
| 忽略推理过程 | 获取reasoning_content |
| 忽略余额不足 | 处理insufficient_balance错误 |
| 不使用推理模型 | 复杂问题使用deepseek-reasoner |
拓展参考资料
官方文档
进阶学习路径
💡 记住:DeepSeek以其超高性价比著称,是国内开发者的首选AI API之一。善用deepseek-reasoner可以解决复杂的推理问题。
